Frequency of Leaks from Conical Centrifuge Tubes.

Introduction: Threaded conical centrifuge tubes are ubiquitous in biological laboratories and are frequently used for the storage/transport of potentially biohazardous samples. However, limited data are available on how frequently and from where these tubes leak. These data are valuable for laboratory biorisk management and to inform future studies on risks arising from the routine use of laboratory consumables. Methods: The frequency of leaks from threaded conical centrifuge tubes was tested using a Glo Germ solution as a tracer. Conical tubes (15 and 50 mL) from several brands were filled, inverted, and placed on their side on the benchtop. After 1 h, the presence or absence of leaks on the benchtop surface, tube threads, and exterior was recorded. Results: We observed that liquid leaked out of tubes that were apparently properly threaded in 2% of 15 mL tubes (confidence interval [95% CI] 1.4-2.6) and 1.4% of 50 mL tubes (95% CI 0.2-1.5). After opening, liquid was found on the threads on the outside of the tube in 20% of 15 mL tubes (95% CI 10-31) and 14% of 50 mL tubes (95% CI 1-28). We did not find sufficient evidence that differences in leak rates among brands were practically significant. Conclusions: The fact that leaks were not uncommonly observed from conical centrifuge tubes suggests that mitigations for any hazard posed by a leak should be a component of every biorisk management strategy for protocols involving the manipulation of hazardous substances in these tubes. Further research should be conducted on other activities that could cause tubes to leak (such as centrifugation or vortexing) and should be completed to understand the risks associated with this consumable. Research into the costs and benefits of mitigating the risk of leaks from conical tubes is recommended.

Rate of Splashes When Opening Microfuge Tubes with Various Methods.

Introduction: Snap-cap microcentrifuge tubes are ubiquitous in biological laboratories. However, limited data are available on how frequently splashes occur when opening them. These data would be valuable for biorisk management in the laboratory. Methods: The frequency of splashes from opening snap-cap tubes using four different methods was tested. The splash frequency for each method was measured on the benchtop surface and on the experimenter's gloves and smock, using a Glo Germ solution as a tracer. Results: Splashes occurred very frequently when opening microcentrifuge snap-cap tubes, no matter which method was used to open the tube. The highest rate of splashes on all surfaces was observed with the one-handed (OH) opening method compared with two-handed methods. Across all methods, the highest rate of splashes was observed on the opener's gloves (70-97%) compared with the benchtop (2-40%) or the body of the researcher (0-7%). Conclusions: All tube opening methods we studied frequently caused splashes, with the OH method being the most error-prone but no two-handed method being clearly superior to any other. In addition to posing an exposure risk to laboratory personnel, experimental repeatability may be affected due to loss of volume when using snap-cap tubes. The rate of splashes underscores the importance of secondary containment, personal protective equipment, and good protocols for decontamination. When working with especially hazardous materials, alternatives to snap-cap tubes (such as screw cap tubes) should be strongly considered. Future studies can examine other methods of opening snap-cap tubes to determine whether a truly safe method exists.

Perceptions of blind proficiency testing among latent print examiners.

In recent years, scholars have levied multiple criticisms against traditional proficiency testing procedures in forensic laboratories. Consequently, on several occasions, authorities have formally recommended that laboratories implement blind proficiency testing procedures. Implementation has been slow, but laboratory management has increasingly expressed interest in initiating blind testing in at least some forensic disciplines, with some laboratories conducting blind testing in almost all disciplines. However, little is known about how a key population perceives blind proficiency testing, i.e., forensic examiners. We surveyed active latent print examiners (N = 338) to explore perceptions of blind proficiency testing and determine whether beliefs varied between examiners who work for laboratories with and without blind proficiency testing. Results suggest that examiners do not hold particularly strong beliefs about such procedures, but that examiners who work in laboratories with blind proficiency testing procedures view them significantly more positively than those who do not. Further, examiner responses provide insight into potential obstacles to continued implementation.

What types of information can and do latent print examiners review? A survey of practicing examiners.

Understanding typical work practices is important to understanding the decision-making process underlying latent print comparison and improving the reliability of the discipline. Despite efforts to standardize work practices, a growing literature has demonstrated that contextual effects can influence every aspect of the analytic process. However, very little is known about what types of information are available to latent print examiners, and what types of information latent print examiners routinely review. We surveyed practicing latent print examiners (N = 284) regarding what types of information are accessible during routine casework, and what types of information they routinely review during casework. We also explored whether access and inclination to review different types of information vary according to unit size and examiner role. Results indicated that information describing the physical evidence is accessible by almost all examiners (94.4%), and most examiners have access to offense type (90.5%), method of evidence collection (77.8%), and the names of both suspect (76.1%) and victim (73.9%). However, evidence description (86.3%) and method of evidence collection (68.3%) were the only information types consistently reviewed by most examiners. Findings also indicate that examiners in smaller laboratories have access to more information types and often review more information types than examiners from larger laboratories, but both populations choose to not review information at similar rates. Further, examiners in supervisory positions are more likely to choose to not review information than examiners in non-supervisory positions. Although there is some consensus regarding what types of information examiners routinely review, findings suggest that there is little absolute consensus regarding what information examiners can even access, and highlight two sources of variability in examiner work practices: employment setting and examiner role. This is concerning in light of efforts to maximize the reliability of analytic procedures (and ultimately, conclusions) and represents an important area of future study as the field progresses.

Considerations on staffing levels for a modern assisted reproductive laboratory.

The duties recently performed in the embryology laboratory have deeply increased compared to those realized a couple of decades ago. Currently, procedures include conventional in vitro fertilization (IVF) and ICSI techniques, or processing of surgically retrieved sperm, embryo culture and time-lapse monitoring, blastocyst culture, as well as trophectoderm biopsy for preimplantation genetic testing and cryopreservation. These techniques require not only time, but also high knowledge level and acutely concentration by the embryologist team. The existing data indicate that an IVF laboratory need to have adequate staffing levels to perform the required daily duties, and to work in optimal conditions that are critical to assure a high quality service, as well as avoiding incidents and to provide the best outcomes. As a result, IVF clinics have invested in human resources, but there is still a large discrepancy between IVF centres on the number of embryologists employed. Currently there is no golden standard on the human resource requirements for assisted reproductive technology procedures; therefore, in this review paper we aim to provide arguments to take into account to determine the embryology staffing requirements in an embryology laboratory to assure optimal safety and efficiency of operations.

Standards in semen examination: publishing reproducible and reliable data based on high-quality methodology.

Biomedical science is rapidly developing in terms of more transparency, openness and reproducibility of scientific publications. This is even more important for all studies that are based on results from basic semen examination. Recently two concordant documents have been published: the 6th edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen, and the International Standard ISO 23162:2021. With these tools, we propose that authors should be instructed to follow these laboratory methods in order to publish studies in peer-reviewed journals, preferable by using a checklist as suggested in an Appendix to this article.

Microbial Aerosols Generated from Standard Microbiological Laboratory Procedures.

Background: Modern microbiology laboratories are designed to protect workers and the environment from microbial aerosols produced during microbiological procedures and accidents. However, there is only limited data available on the aerosols generated from common microbiology procedures. Methods: A series of common microbiological procedures were undertaken with high concentration spore suspensions while air samplers were operated to sample the aerosols generated. Surface contamination from droplets was visualized using sodium fluorescein within the suspension. A total of 36 procedures were studied using different sample volumes (0.1-10 mL) and two spore suspension titers (107 and 109 colony forming units [cfu]/mL). Results: The aerosol concentrations generated varied from 0 to 13,000 cfu/m3. There was evidence to suggest that titer, volume, and poor use of equipment were significant factors in increased aerosol generation from some of the procedures. A risk assessment undertaken using the data showed that any aerosol generated from these processes would be contained within a correctly operating biological safety cabinet. Therefore, with these procedures, the operator and the environment would not require any additional protective measures such as respiratory protective equipment or a negative pressure laboratory to prevent aerosol exposure or release. Conclusions: Aerosol generation from common laboratory processes can be minimized by reducing sample volumes and concentrations if possible. Training laboratory staff in good microbiological techniques would further mitigate aerosols generated from common laboratory processes.

Climate crisis and ecological emergency: Why they concern (neuro)scientists, and what we can do.

Our planet is experiencing severe and accelerating climate and ecological breakdown caused by human activity. As professional scientists, we are better placed than most to understand the data that evidence this fact. However, like most other people, we ignore this inconvenient truth and lead our daily lives, at home and at work, as if these facts weren't true. In particular, we overlook that our own neuroscientific research practices, from our laboratory experiments to our often global travel, help drive climate change and ecosystem damage. We also hold privileged positions of authority in our societies but rarely speak out. Here, we argue that to help society create a survivable future, we neuroscientists can and must play our part. In April 2021, we delivered a symposium at the British Neuroscience Association meeting outlining what we think neuroscientists can and should do to help stop climate breakdown. Building on our talks (Box 1), we here outline what the climate and ecological emergencies mean for us as neuroscientists. We highlight the psychological mechanisms that block us from taking action, and then outline what practical steps we can take to overcome these blocks and work towards sustainability. In particular, we review environmental issues in neuroscience research, scientific computing, and conferences. We also highlight the key advocacy roles we can all play in our institutions and in society more broadly. The need for sustainable change has never been more urgent, and we call on all (neuro)scientists to act with the utmost urgency.

Birthweight and other perinatal outcomes of singletons conceived after assisted reproduction compared to natural conceived singletons in couples with unexplained subfertility: follow-up of two randomized clinical trials.

STUDY QUESTION: Does assisted reproduction, such as ovarian stimulation and/or laboratory procedures, have impact on perinatal outcomes of singleton live births compared to natural conception in couples with unexplained subfertility? SUMMARY ANSWER: Compared to natural conception, singletons born after intrauterine insemination with ovarian stimulation (IUI-OS) had a lower birthweight, while singletons born after IVF had comparable birthweights, in couples with unexplained subfertility. WHAT IS KNOWN ALREADY: Singletons conceived by assisted reproduction have different perinatal outcomes such as low birthweight and a higher risk of premature birth than naturally conceived singletons. This might be due to the assisted reproduction, such as laboratory procedures or the ovarian stimulation, or to an intrinsic factor in couples with subfertility. STUDY DESIGN, SIZE, DURATION: We performed a prospective cohort study using the follow-up data of two randomized clinical trials performed in couples with unexplained subfertility. We evaluated perinatal outcomes of 472 live birth singletons conceived after assisted reproduction or after natural conception within the time horizon of the studies. PARTICIPANTS/MATERIALS, SETTING, METHODS: To assess the possible impact of ovarian stimulation we compared the singletons conceived after IUI with FSH or clomiphene citrate (CC) and IVF in a modified natural cycle (IVF-MNC) or standard IVF with single embryo transfer (IVF-SET) to naturally conceived singletons in the same cohorts. To further look into the possible effect of the laboratory procedures, we put both IUI and IVF groups together into IUI-OS and IVF and compared both to singletons born after natural conception. We only included singletons conceived after fresh embryo transfers. The main outcome was birthweight presented as absolute weight in grams and gestational age- and gender-adjusted percentiles. We calculated differences in birthweight using regression analyses adjusted for maternal age, BMI, smoking, parity, duration of subfertility and child gender. MAIN RESULTS AND THE ROLE OF CHANCE: In total, there were 472 live birth singletons. Of the 472 singleton pregnancies, 209 were conceived after IUI-OS (136 with FSH and 73 with CC as ovarian stimulation), 138 after IVF (50 after IVF-MNC and 88 after IVF-SET) and 125 were conceived naturally.Singletons conceived following IUI-FSH and IUI-CC both had lower birthweights compared to naturally conceived singletons (adjusted difference IUI-FSH -156.3 g, 95% CI -287.9 to -24.7; IUI-CC -160.3 g, 95% CI -316.7 to -3.8). When we compared IVF-MNC and IVF-SET to naturally conceived singletons, no significant difference was found (adjusted difference IVF-MNC 75.8 g, 95% CI -102.0 to 253.7; IVF-SET -10.6 g, 95% CI -159.2 to 138.1). The mean birthweight percentile was only significantly lower in the IUI-FSH group (-7.0 percentile, 95% CI -13.9 to -0.2). The IUI-CC and IVF-SET group had a lower mean percentile and the IVF-MNC group a higher mean percentile, but these groups were not significant different compared to the naturally conceived group (IUI-CC -5.1 percentile, 95% CI -13.3 to 3.0; IVF-MNC 4.4 percentile, 95% CI -4.9 to 13.6; IVF-SET -1.3 percentile, 95% CI -9.1 to 6.4).Looking at the laboratory process that took place, singletons conceived following IUI-OS had lower birthweights than naturally conceived singletons (adjusted difference -157.7 g, 95% CI -277.4 to -38.0). The IVF group had comparable birthweights with the naturally conceived group (adjusted difference 20.9 g, 95% CI -110.8 to 152.6). The mean birthweight percentile was significantly lower in the IUI-OS group compared to the natural group (-6.4 percentile, 95% CI -12.6 to -0.1). The IVF group was comparable (0.7 percentile, 95% CI -6.1 to 7.6). LIMITATIONS, REASONS FOR CAUTION: The results are limited by the number of cases. The data were collected prospectively alongside the randomized controlled trials, but analyzed as treated. WIDER IMPLICATIONS OF THE FINDINGS: Our data suggest IUI in a stimulated cycle may have a negative impact on the birthweight of the child and possibly on pre-eclampsia. Further research should look into the effect of different methods of ovarian stimulation on placenta pathology and pre-eclampsia in couples with unexplained subfertility using naturally conceived singletons in the unexplained population as a reference. STUDY FUNDING/COMPETING INTEREST(S): Both initial trials were supported by a grant from ZonMW, the Dutch Organization for Health Research and Development (INeS 120620027, SUPER 80-83600-98-10192). The INeS study also had a grant from Zorgverzekeraars Nederland, the Dutch association of healthcare insurers (09-003). B.W.J.M. is supported by an NHMRC investigator Grant (GNT1176437) and reports consultancy for ObsEva, Merck Merck KGaA, Guerbet and iGenomix, outside the submitted work. A.H. reports grants from Ferring Pharmaceutical company (the Netherlands), outside the submitted work. F.J.M.B. receives monetary compensation as a member of the external advisory board for Merck Serono (the Netherlands), Ferring Pharmaceutics BV (the Netherlands) and Gedeon Richter (Belgium), he receives personal fees from educational activities for Ferring BV (the Netherlands) and for advisory and consultancy work for Roche and he receives research support grants from Merck Serono and Ferring Pharmaceutics BV, outside the submitted work. The remaining authors have nothing to disclose. TRIAL REGISTRATION NUMBER: INeS study Trial NL915 (NTR939); SUPER Trial NL3895 (NTR4057).

The Effect of Laboratory Procedures and Repeated-glazing on Color of Metal-ceramic Restoration.

BACKGROUND: Routine laboratory procedures and repeated glazed effect the final color of metal-ceramic restorations (MCRs). Clinicians wonder if the color changes after routine laboratory procedures and repeated glazed is clinically acceptable or not. AIMS: The aim of this study was to determine the color changes of MCRs after routine laboratory procedures and then glazed for 1, 2, and 3 times. MATERIALS AND METHODS: Forty-five disc-shaped (10-mm diameter and 1-mm thickness) specimens were fabricated from Cr-Co metal-alloy. Bonding agent, first and second layer of shade A2 opaque porcelain (OP) were applied on the metal specimens. The color of specimens was measured with a spectrophotometer after each procedure and △E1, △E2, and △E3 values were calculated. Shade A2 feldspathic porcelain was applied (2-mm thickness) to all specimens. Glaze was applied on the porcelain for 1, 2, and 3 times and then, the color measured after each procedure and △E4, △E5, and △E6 values were calculated. Data were analyzed with one-way ANOVA and Duncan test (P < 0.05). RESULTS: △E1 that was obtained between the first layer of OP and bonding agent showed the greatest value. △E2 that was obtained between the second and first layer of OP showed the lowest value. After repeated glazed procedures, the final color of the specimens was changed; but, these changes were clinically acceptable (△E < 5.5). CONCLUSIONS: The routine laboratory procedures and glazed for 1,2, and 3 times is effect the color of MCRs; but, the color changes were clinically acceptable (△E < 5.5).

Optimization of laboratory procedures for intrauterine insemination: survey of methods in relation to clinical outcome.

BACKGROUND: There is a wide practice variation of used methods and outcomes in IUI in fertility laboratories. Standardization of the IUI procedure is important for reducing inconsistency among laboratories in counseling infertile couples and in pregnancy results. The aim of the study was to evaluate the currently used laboratory procedures of IUI in Dutch fertility laboratories and their effect on IUI pregnancy results. Additionally, the methods for semen analysis (SA) were evaluated, as SA is related to IUI in terms of inseminated sperm number and IUI counseling. MATERIAL AND METHODS: This questionnaire survey study was sent to laboratories participating in the Dutch external quality control program for semen analysis (SKML) and consisted of 46 questions concerning laboratory management, methods for semen analysis and IUI, and clinical results. The results were analyzed using univariable and multivariable logistic regression models. RESULTS: A total of 52 laboratories (out of 99) provided information on used methodologies for SA or laboratory procedures of IUI and the organization of the laboratory. A wide variability was confirmed in used methods for both SA and IUI. Evaluation of pregnancy results obtained during 3 years (2013-2015) showed that specific used laboratory methods have a significant effect on the probability of becoming pregnant. DISCUSSION AND CONCLUSION: Important to remark is that in this survey study cycle-specific data, including variables of the individual couples (age, stimulation protocol, etc), were not included and may have effects on the results. The reported results provide an overview of the current practice performance; however, the organization of fertility laboratories is changing rapidly. The use of standardized methods in IUI is important for optimizing the performance of care and improving pregnancy results. The knowledge on used procedures, however, is limited, and further research on factors involving SA and the IUI procedure is necessary.

Standardization of laboratory lipid profile assessment: A call for action with a special focus on the 2016 ESC/EAS dyslipidemia guidelines - Executive summary: A consensus endorsed by the Cardiovascular Risk and Prevention Group of the Portuguese Internal Medicine Society, the Portuguese Atherosclerosis Society, the Portuguese Society of Cardiology, the Portuguese Society of Laboratory Medicine, and the Portuguese Association of Clinical Chemistry.

Even with improvements in lifestyle interventions, better control of cardiovascular (CV) risk factors, and improvements in CV outcomes, cardiovascular disease (CVD) remains the leading cause of morbidity and mortality in Portugal and Europe. Atherogenic dyslipidemias, particularly hypercholesterolemia, have a crucial causal role in the development of atherosclerotic CVD. The clinical approach to a patient with dyslipidemia requires an accurate diagnosis, based on harmonized and standardized lipid and lipoprotein laboratory assessments. Results and reports of these tests, together with assessment of total CV risk and the respective therapeutic targets, will help ensure that clinical guidelines and good clinical practices are followed, increasing the reliability of screening for lipid disorders, producing more accurate diagnoses and CV risk stratification, and improving CV prevention. To this end, this consensus aims to provide clinicians with practical guidance for the harmonization and standardization of laboratory lipid tests, focusing on the most recent dyslipidemia management guidelines.

Compatibility of preparatory procedures for the analysis of cortisol concentrations and stable isotope (δ13C, δ15N) ratios: a test on brown bear hair.

The measurement of naturally occurring glucocorticoids and stable isotopes of several elements has gained importance in wildlife studies in recent decades and opened a myriad of ecological applications. Cortisol and stable isotopes equilibrate in animal tissues over periods of integration related to the growth rate of the tissue, providing information reflecting systemic cortisol secretion and dietary intake. Sample preparation shares the common step of first cleaning the sample of external contamination. However, it is not well understood how different solvents used in sample preparation affect isotopic and cortisol values, and whether it is safe to follow the same procedures for both measures to optimize analyses of the same sample. We conducted an experiment to compare different preparation protocols for the analysis of cortisol concentrations and stable carbon (δ13C) and nitrogen (δ15N) isotope ratios in hair. Hair samples from 12 brown bears (Ursus arctos) were each divided into five aliquots; two aliquots were rinsed with a 2:1 chloroform:methanol (v/v) mixture with one aliquot ground prior to cortisol analysis and the other left intact for stable isotope analyses; two aliquots were washed with methanol with one aliquot ground prior to cortisol analysis and the other left intact for stable isotope analyses; and one aliquot washed with methanol and ground prior to stable isotope analyses. The cortisol, δ13C and δ15N values remained consistent following all treatments. Our results indicate that hair samples rinsed with a 2:1 chloroform:methanol mixture or washed with methanol can be used for both types of analyses. Further, hair that has been ground in a standard hair cortisol procedure can also be used for stable isotope analysis. This information is important for improving laboratory efficiency and compatibility of procedures used for wildlife physiological ecology studies where concurrent measurements of cortisol and stable isotopes in hair are required.

Stochastic modelling of viral blips in HIV-1-infected patients: effects of inhomogeneous density fluctuations.

We propose a stochastic model of HIV-1 infection dynamics under HAART in order to analyse the origin and dynamics of the so-called viral blips, i.e. episodes of transient viremia that occur in the phase of where the disease remains in a latent state during which the viral load raises above the detection limit of standard clinical assays. Based on prior work in the subject, we consider an infection model in which latently infected cell compartment sustains a residual (latent) infection over long periods of time. Unlike previous models, we include the effects of inhomogeneities in cell and virus concentration in the blood stream. We further consider the effect of burst virion production. By comparing with the experimental results obtained during a study in which intensive sampling was carried out on HIV-1-infected patients undergoing HAART over a long period of time, we conclude that our model supports the hypothesis that viral blips are consistent with random fluctuations around the average viral load. We further observe that agreement between our simulation results and the blip statistics obtained in the aforementioned study improves when burst virion production is considered. We also study the effect of sample manipulation artifacts on the results produced by our model, in particular, that of the post-extraction handling time, i.e. the time elapsed between sample extraction and actual test. Our results support the notion that the statistics of viral blips can be critically affected by such artifacts.

Existing data sources for clinical epidemiology: The clinical laboratory information system (LABKA) research database at Aarhus University, Denmark.

This paper provides an introduction to the clinical laboratory information system (LABKA) research database in Northern and Central Denmark. The database contains millions of stored laboratory test results for patients living in the two Danish regions, encompassing 1.8 million residents, or one-third of the country's population. More than 1700 different types of blood test analyses are available. Therefore, the LABKA research database represents an incredible source for studies involving blood test analyses. By record linkage of different Danish registries with the LABKA research database, it is possible to examine a large number of biomarkers as predictors of disease risk and prognosis and as markers of disease severity, and to evaluate medical treatments regarding effectiveness and possible side effects. Large epidemiological studies using routinely stored blood test results for individual patients can be performed because it is possible to link the laboratory data to high-quality individual clinical patient data in Denmark.

Human herpesvirus 8 transmission from mother to child and between siblings in an endemic population.

BACKGROUND: Transmission of human herpesvirus 8 (HHV-8), the aetiological agent of Kaposi's sarcoma, is known to occur during sex among homosexual men. However, other modes of HHV-8 transmission remain to be elucidated in endemic populations. METHODS: We did a population-based seroepidemiological survey in a village in French Guiana among 1337 individuals of African origin (age 2-91 years) who had reliable genealogical data. Plasma samples were taken and tested for HHV-specific IgG by immunofluorescence assay. Risk factors and familial correlations for HHV-8 seropositivity were modelled by logistic regression analysis by use of the estimating equations approach, which expresses familial dependences in terms of odds ratios. Familial odds ratios were also acquired by use of the distribution of all possible pairs of a given familial dependence. FINDINGS: The overall HHV-8 seroprevalence was 13.2% with no difference according to sex. HHV-8 seropositivity was strongly age dependent: at 1.2% under 5 years, HHV-8 seroprevalence rose up to a plateau around 15% between 15 and 40 years, and showed a seroprevalence of more than 27% in individuals older than 40 years. Strong familial aggregation in HHV-8 seroprevalence was found with high mother-child (odd ratio 2.8 [95% CI 1.6-5.0]) and sib-sib (3.8 [1.6-9.5]) correlations. By contrast, no significant correlation between spouses (0.6 [0.2-1.9]) was seen. INTERPRETATION: This pattern of familial aggregation, together with the variation of HHV-8 seroprevalence with age, indicate that, in endemic populations, HHV-8 transmission mainly occurs from mother to child and between siblings during childhood and adolescence.

Validation of spot-testing kits to determine iodine content in salt.

Iodine deficiency disorders are a major public health problem, and salt iodization is the most widely practised intervention for their elimination. For the intervention to be successful and sustainable, it is vital to monitor the iodine content of salt regularly. Iodometric titration, the traditional method for measuring iodine content, has problems related to accessibility and cost. The newer spot-testing kits are inexpensive, require minimal training, and provide immediate results. Using data from surveys to assess the availability of iodized salt in two states in India, Madhya Pradesh and the National Capital Territory of Delhi, we tested the suitability of such a kit in field situations. Salt samples from Delhi were collected from 30 schools, chosen using the Expanded Programme on Immunization (EPI) cluster sampling technique. A single observer made the measurement for iodine content using the kit. Salt samples from Madhya Pradesh were from 30 rural and 30 urban clusters, identified by using census data and the EPI cluster sampling technique. In each cluster, salt samples were collected from 10 randomly selected households and all retailers. The 15 investigators performing the survey estimated the iodine content of salt samples in the field using the kit. All the samples were brought to the central laboratory in Delhi, where iodine content was estimated using iodometric titration as a reference method. The agreement between the kit and titration values decreased as the number of observers increased. Although sensitivity was not much affected by the increase in the number of observers (93.3% for a single observer and 93.9% for multiple observers), specificity decreased sharply (90.4% for a single observer and 40.4% for multiple observers). Due to the low specificity and resulting high numbers of false-positives for the kit when used by multiple observers ("real-life situations"), kits were likely to consistently overestimate the availability of iodized salt. This overestimation could result in complacency. Therefore, we conclude that until a valid alternative is available, the titration method should be used for monitoring the iodine content of salt at all levels, from producer to consumer, to ensure effectiveness of the programme.

Copper corrosion-simulated uterine solutions.

We studied the copper corrosion and product layers originating in a simulated uterine solution at pH values 6.3 and 8.0 for 15, 65, 180, and 360 days at 37 degrees C. Absorbance measurements were performed. Corrosion product layers on the copper surface were characterized by scanning electron microscopy, energy dispersive x-ray, and x-ray photo-electron spectroscopy techniques. Copper release for pH 6.3 and 8.0 was 3.4-4.5 microg/day for 15 days and 0.1-0.3 microg/day for 360 days. Of the order of 30%-40% of dissolved cupric ions were trapped in the product layers. The main compounds identified were cuprite (Cu(2)O), calcite (CaCO(3)), and phosphates.

The roles of clinical assessment, human chorionic gonadotropin assays, and ultrasonography in medical abortion practice.

The clinical assessment of patients who request early medical abortion includes confirmation of the diagnosis of pregnancy and estimation of gestational age. Accurate gestational dating is essential, because the efficacies of medical abortion regimens decline as pregnancy advances. Whereas medical abortion researchers in the United States have relied on routine ultrasonography for gestational dating, abortion providers experienced with mifepristone and prostaglandin regimens outside the United States have reported high efficacy and safety primarily with clinical dating parameters. Diligent follow-up of patients allows clinicians to confirm that complete abortion has occurred without complications. In cases of uncertain outcome or suspected ectopic pregnancy, transvaginal ultrasonography and beta-human chorionic gonadotropin assays can assist in prompt diagnosis and management. As medical abortion with mifepristone and misoprostol becomes more prevalent in the United States, studies will be needed to further evaluate the effects of these modalities on medical abortion outcomes.

Hippurate hydrolysis and Christie, Atkins, Munch-Peterson tests as epidemiological diagnostic tools for Streptococcus agalactiae carriage in pregnancy.

OBJECTIVE: To evaluate the Christie, Atkins, Munch-Peterson (CAMP) and hippurate hydrolysis reactions as diagnostic tools for Streptococcus agalactiae carriage in pregnancy. DESIGN: Observational, analytical case-control study. SETTING: Hospital-based study in a primary and a tertiary health care institution. PATIENTS: One hundred and six pregnant and 56 non-pregnant (controls) women were included in the study. The participants were of different socio-economic status. A volunteer sample was used. About 800 subjects were contacted and 162 participated in the study. RESULTS: The sensitivity of the screening test varied from 25% for the CAMP test to 77.78% for the hippurate hydrolysis reaction. The specificity was the same for both tests at (50%). A significant difference in positivity between the CAMP and hippurate hydrolysis reactions (95% confidence limit, P < 0.05) was observed. The predictive values of the positive test were 66.6% (CAMP) and 87.55% (hippurate hydrolysis) while the negative test were 14.29% (CAMP) and 33.30% (hippurate hydrolysis). Pregnant women had 0.33 chances of being GBS carriers with the CAMP compared to 3.5 with the hippurate hydrolysis. CONCLUSION: The hippurate hydrolysis test is highly recommended since the reagents are easily available and the organism was easily isolated using this method. The presence of GBS in the anorectum and endocervix is likely to induce systemic and local immunity in the female genital tract. This can contribute to the development of a mucosal vaccine for GBS diseases.