Influence of Gestational Diabetes Mellitus on Diabetes Risk and Glycemic Control in a Retrospective Population-Based Cohort

OBJECTIVE

Racial/ethnic-specific estimates of the influence of gestational diabetes mellitus (GDM) on type 2 diabetes remain underexplored in large population-based cohorts. We estimated racial/ethnic differences in the influence of GDM on diabetes risk and glycemic control in a multiethnic, population-based cohort of postpartum women.

RESEARCH DESIGN AND METHODS

Hospital discharge and vital registry data for New York City (NYC) births between 2009 and 2011 were linked with NYC A1C Registry data between 2009 and 2017. Women with baseline diabetes (n = 2,810) were excluded for a final birth cohort of 336,276. GDM on time to diabetes onset (two A1C tests of ≥6.5% from 12 weeks postpartum onward) or glucose control (first test of A1C <7.0% following diagnosis) was assessed using Cox regression with a time-varying exposure. Models were adjusted for sociodemographic and clinical factors and stratified by race/ethnicity.

RESULTS

The cumulative incidence for diabetes was 11.8% and 0.6% among women with and without GDM. The adjusted hazard ratio (aHR) of GDM status on diabetes risk was 11.5 (95% CI 10.8, 12.3) overall, with slight differences by race/ethnicity. GDM was associated with a lower likelihood of glycemic control (aHR 0.85; 95% CI 0.79, 0.92), with the largest negative influence among Black (aHR 0.77; 95% CI 0.68, 0.88) and Hispanic (aHR 0.84; 95% CI 0.74, 0.95) women. Adjustment for screening bias and loss to follow-up modestly attenuated racial/ethnic differences in diabetes risk but had little influence on glycemic control.

CONCLUSIONS

Understanding racial/ethnic differences in the influence of GDM on diabetes progression is critical to disrupt life course cardiometabolic disparities.

Exploring the accuracy of self-reported maternal and newborn care in select studies from low and middle-income country settings: do respondent and facility characteristics affect measurement?

BACKGROUND

Accurate data on the receipt of essential maternal and newborn health interventions is necessary to interpret and address gaps in effective coverage. Validation results of commonly used content and quality of care indicators routinely implemented in international survey programs vary across settings. We assessed how respondent and facility characteristics influenced the accuracy of women's recall of interventions received in the antenatal and postnatal periods.

METHODS

We synthesized reporting accuracy using data from a known sample of validation studies conducted in Sub-Saharan Africa and Southeast Asia, which assessed the validity of women's self-report of received antenatal care (ANC) (N = 3 studies, 3,169 participants) and postnatal care (PNC) (N = 5 studies, 2,462 participants) compared to direct observation. For each study, indicator sensitivity and specificity are presented with 95% confidence intervals. Univariate fixed effects and bivariate random effects models were used to examine whether respondent characteristics (e.g., age group, parity, education level), facility quality, or intervention coverage level influenced the accuracy of women's recall of whether interventions were received.

RESULTS

Intervention coverage was associated with reporting accuracy across studies for the majority (9 of 12) of PNC indicators. Increasing intervention coverage was associated with poorer specificity for 8 indicators and improved sensitivity for 6 indicators. Reporting accuracy for ANC or PNC indicators did not consistently differ by any other respondent or facility characteristic.

CONCLUSIONS

High intervention coverage may contribute to higher false positive reporting (poorer specificity) among women who receive facility-based maternal and newborn care while low intervention coverage may contribute to false negative reporting (lower sensitivity). While replication in other country and facility settings is warranted, results suggest that monitoring efforts should consider the context of care when interpreting national estimates of intervention coverage.

The relationship between hormonal contraception and cervical dysplasia/cancer controlling for human papillomavirus infection: A systematic review

OBJECTIVE

Studies on the effect of long-term use of combined oral contraceptives (COCs) on cervical dysplasia and/or cancer risk have been inconsistent. Less is known about the effects of other forms of hormonal contraception (HC). We examine whether HC use increases the risk of incident cervical intraepithelial neoplasia (CIN) 2, 3 and/or cancer after accounting for preexisting human papillomavirus (HPV) infection.

STUDY DESIGN

Systematic review of prospective studies on HC use as risk factor for cervical dysplasia with HPV infection documented prior to outcome assessment including PubMed and EMBASE records between January 2000 and February 2020 (Prospero #CRD42019130725).

RESULTS

Among nine eligible studies, seven described recency and type of HC use and therefore comprise the primary analysis; two studies limit comparisons to ever versus never use and are summarized separately. All seven studies explored the relationship between oral contraceptive (OC) use and cervical dysplasia/cancer incidence: two found increased risk (adjusted odds ratio, aOR = 1.5-2.7), one found no association but decreased risk when restricted to women with persistent HPV (adjusted hazard ratio = 0.5), and four found no association. None of the seven studies differentiated between COC and progestin-only pills (POPs) by use recency or duration. The only study that included injectable progestin-only contraception (DMPA) found increased CIN3 incidence among current versus never users (aOR = 1.6). The one study that included Norplant found no association. Two studies included intrauterine device (IUD) use, but did not differentiate between hormonal and copper IUDs, and found no association.

CONCLUSION

We found no consistent evidence that OC use is associated with increased risk for cervical dysplasia/cancer after controlling for HPV infection. There were too few studies of progestin-only injectables, implants or IUDs to assess their effect on cervical dysplasia/cancer risk.

IMPLICATIONS

Use of single self-reported HC measures and insufficient distinction by hormonal constituent cloud our understanding of whether some HCs increase risk for cervical cancer. Methodologically rigorous studies with distinct HCs measured as time-varying exposures are needed to inform cervical cancer prevention efforts and improve our understanding of cervical cancer etiology.

The development of adolescent agency and implications for reproductive choice among girls in Zambia

Background

A substantial proportion of adolescent girls in Zambia lack the ability to decide their reproductive future. We examined the role of agency in early and unwanted adolescent childbearing.

Methods

Using latent transition analysis, we characterized a multi-dimensional profile of adolescent agency annually over a four-year period. We investigated the influence of early life access to resources and time-varying predictors (school retention, violence, early marriage and unwanted/mistimed pregnancy and childbearing) on agency profile membership as well as transitions in agency status over time.

Results

Four agency profiles were identified, with differences by age cohort (10–14 years vs. 15–19 years). Three profiles identified in both age cohorts were: Low-moderate agency, Self-assured gender conformers, and High agency. Unique to younger girls was the Gender conscious, low belief in abilities status, while among older girls was the Self-assured selective gender conscious status. While younger girls were likely to transition to the highest agency status over time, high agency membership declined among older girls. Early life resources were associated with augmented agency while exposure to negative events, particularly early marriage, were associated with detraction from high agency status. Girls who expressed high self-efficacy but gender-conforming values were most at risk of early marriage and unwanted/mistimed pregnancy while High agency girls were at comparatively low risk.

Conclusions

Results show agency is dynamic but less mutable with increasing age. Early adolescent strategies which address inequitable gender norms and limit early marriage, may guard against losses to agency which contribute to unwanted fertility outcomes.

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Findings support agency as a dynamic, multidimensional construct in adolescence.

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In general, access to resources promoted agency across dimensions.

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Time-varying events, particularly early marriage, detracted from agency status.

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Agency dimensions combined in unique ways with distinct implications for early/unwanted fertility.

The Validity of Women's Reports of Family Planning Service Quality in Cambodia and Kenya

Population-based indicators of the coverage of key elements of high-quality family planning services are tracked via household surveys with female respondents, yet little work has been done to establish their validity. We take advantage of existing data sets from Cambodia and Kenya to compare women's responses at exit interviews following a health facility visit against the observations of a trained third-party observer during the visit. The results, which treat the observations as the reference standard, show that indicators that measure contraceptive methods received are accurately reported while indicators of whether the woman received her preferred method and whether information was "discussed" or "explained" during counseling are less reliably reported. Studies designed explicitly to assess the validity of family planning questions in household surveys, especially questions in large survey programs critical for monitoring demographic trends and programmatic coverage, are needed.

Validating women’s reports of antenatal and postnatal care received in Bangladesh, Cambodia and Kenya

Background

Global indicators for monitoring progress in maternal and newborn health have tended to rely on contact coverage indicators rather than the content of services received. As part of the effort to improve measurement of progress in maternal and newborn health, this study examines how accurately women can report on information and health interventions received during an antenatal or postnatal health consultation at health facilities in Bangladesh, Cambodia and Kenya.

Methods

We conducted secondary analysis of matched observation and client interview data to compare women’s reports of care received at exit interview with observation by a trained third-party observer. We assessed indicator accuracy by calculating sensitivity, specificity, area under the receiver operating characteristic curve (AUC) and inflation factor (IF). Indicators considered to have both high individual accuracy (an AUC value of 0.70 or greater) and low population-level bias (0.75<IF<1.25) were considered to have acceptable validity. In addition, we considered the number of countries where both validation criteria were met.

Results

For indicators of antenatal care, we found 16 of 18 indicators in Bangladesh, 3 of 6 in Cambodia and 3 of 8 in Kenya met both validation criteria. For postnatal care, we found evidence of acceptable validity for 6 of 8 indicators in Bangladesh, 5 of 14 in Cambodia and 3 of 16 in Kenya. In general, we documented higher validity for indicators related to concrete, observable actions, as opposed to information or advice given. Women were more likely to recall care received for themselves, rather than for their newborn.

Conclusions

Women reported accurately on multiple aspects of antenatal and postnatal care. While we describe broad patterns in the types of indicators likely to be recalled with accuracy, differences by setting warrant further investigation. Findings inform efforts to better monitor the coverage and quality of maternal and newborn health interventions.

The links between women's employment and children at home: Variations in low- and middle-income countries by world region

As fertility declines in low- and middle-income countries, the time women devote to childbearing and rearing may also be reduced. This shift has been described as one of the positive consequences of the demographic transition, as it opens opportunities for women to pursue educational and employment opportunities that were previously constrained by the demands of bearing and raising children. We estimate the numbers of children residing at home (with their mother) for women in 58 countries in Asia, Latin America, the Middle East and North Africa, and sub-Saharan Africa. We then examine the association between women's employment and having children at home. Finally, we assess trends over recent decades in the relationship between employment and childbearing, and differences in this relationship by mother's occupation. We find a negative association between women's employment and having children at home; this association varies substantially by world region, age of child, and mother's occupation.

Gender, power, and violence: A systematic review of measures and their association with male perpetration of IPV

Introduction

Harmful gender norms, views on the acceptability of violence against women, and power inequities in relationships have been explored as key drivers of male perpetration of intimate partner violence (IPV). Yet such antecedents have been inconsistently measured in the empirical literature. This systematic review aimed to identify which measures of gender inequitable norms, views, relations and practices are currently being used in the field, and which are most closely tied with male IPV perpetration.

Methods

We searched five electronic databases to identify studies published between 2000 and 2015 that reported the association between such gender inequities and male perpetration of IPV. Identified scales were categorized by content area and level of generality, as well as other attributes, and we compared the consistency of scale performance across each category.

Results

Twenty-three studies were identified, employing 64 measures. Scales were categorized into three main thematic areas: views on gender roles/norms, acceptance of violence against women, and gender-related inequities in relationship power and control. We also classified whether the scale was oriented to respondents’ own views, or what they believed others do or think. While overall, measures were positively associated with IPV perpetration in 45% of cases, this finding varied by scale type. Measures inclusive of acceptance of violence against women or beliefs about men’s sexual entitlement, followed by scales that measured respondents’ views on gender roles/norms, were most consistently associated with IPV perpetration. Measures of relationship power showed less consistent associations. We found few scales that measured peer or community norms.

Conclusion

Validated scales that encompass views on the acceptance of violence against women, and scales inclusive of beliefs about men’s sexual entitlement, may be particularly promising for unpacking pathways to IPV perpetration, targeting interventions, and monitoring progress in IPV prevention efforts. A number of gaps in the literature are identified.

Plasma impurities observed by a pulse height analysis diagnostic during the divertor campaign of the Wendelstein 7-X stellarator

The paper reports on the optimization process of the soft X-ray pulse height analyzer installed on the Wendelstein 7-X (W7-X) stellarator. It is a 3-channel system that records X-ray spectra in the range from 0.6 to 19.6 keV. X-ray spectra, with a temporal and spatial resolution of 100 ms and 2.5 cm (depending on selected slit sizes), respectively, are line integrated along a line-of-sight that crosses near to the plasma center. In the second W7-X operation phase with a carbon test divertor unit, light impurities, e.g., carbon and oxygen, were observed as well as mid- to high-Z elements, e.g., sulfur, chlorine, chromium, manganese, iron, and nickel. In addition, X-ray lines from several tracer elements have been observed after the laser blow-off injection of different impurities, e.g., silicon, titanium, and iron, and during discharges with prefill or a gas puff of neon or argon. These measurements were achieved by optimizing light absorber-foil selection, which defines the detected energy range, and remotely controlled pinhole size, which defines photon flux. The identification of X-ray lines was confirmed by other spectroscopic diagnostics, e.g., by the High-Efficiency XUV Overview Spectrometer, HEXOS, and high-resolution X-ray imaging spectrometer, HR-XIS.

Tracer-Encapsulated Solid Pellet (TESPEL) injection system for Wendelstein 7-X

Impurity confinement in fusion plasmas is mainly determined by transport mechanisms in the core region. For the Wendelstein 7-X stellarator, its island divertor is expected to screen effectively external impurity sources in the scrape-off layer at higher densities. However, the unique feature of Tracer-Encapsulated Solid Pellet (TESPEL) injection, releasing impurities at a well-localized radial position directly in the core plasma, enables investigating such transport mechanisms. This paper reports on the detailed design of a completely new TESPEL injection system, which has been designed by the National Institute for Fusion Science, Toki, Japan, and is currently being installed at Max-Planck-Institut für Plasmaphysik, Greifswald, Germany, for the Wendelstein 7-X. This injector consists of a storage and injection unit, attached to a system of guiding tubes which run through 3 successive differential pumping stages. A light-gate system and an optical observation system are used to determine the location of the deposited tracers. Laboratory tests carried out by shooting TESPELs onto a sample foil showed good performance after careful realignment of the guiding tubes.

A Systematic Review of Adolescent Girl Program Implementation in Low- and Middle-Income Countries: Evidence Gaps and Insights

Increasing attention to adolescent girls has generated an abundance of programs and a growing body of research on adolescent girls in low- and middle-income countries. Despite this, questions remain about what implementation approaches in program design are most effective, hindering efficient resource allocation, program scale-up, and replication across settings. To address these questions, we conducted a systematic review to identify lessons learned and gaps in the evidence base. We searched four electronic databases to identify studies published between 1990 and 2014 that evaluated health, social, and/or economic development programs targeting adolescent girls in low- and middle-income countries. Seventy-seven (77) studies meeting specified criteria were identified, of which 19 presented results that allowed conclusions relevant to implementation science. Studies examining the following questions were assessed: To what extent, if any, do multicomponent interventions (as opposed to single-component interventions) improve outcomes for girls? What is the added value of involving actors in addition to the girl herself such as parents, guardians, husbands (i.e., multilevel interventions)? What is the threshold proportion of girls who need to participate in a program to bring about normative and behavior changes at the community level? Is a greater level of program exposure associated with greater programmatic benefit for girls? Can supplemental "booster" activities extend the benefits of a program after it ends? We found evidence to support associations between multicomponent (vs. single component) programs, and longer program exposure (vs. less program exposure), with more favorable outcomes for girls, although both conclusions include methodological limitations. Overall, few studies assessed boosters or program saturation, and evidence on multilevel versus single-level programs was inconclusive. Few studies assessed implementation science questions by design, exposing large gaps in the evidence base. We call for future research to explicitly test such implementation science questions to inform more effective use of resources and to improve outcomes for girls.

Women's recall of maternal and newborn interventions received in the postnatal period: a validity study in Kenya and Swaziland

Background

Despite the concentration of maternal and infant deaths in the early postnatal period, information on the content and quality of postnatal care interventions is not routinely collected in most low and middle-income countries. At present, data on the coverage of postnatal care interventions mostly rely on women’s reports collected in household surveys, such as the Demographic and Health Surveys (DHS) and Multiple Indicator Cluster Surveys (MICS), which collect limited information. We assessed the validity of a set of postnatal care indicators that reflect a range of recommended interventions for both mother and newborn and have potential to be included in household surveys for monitoring of population-level coverage.

Methods

We compared women’s reports in exit interviews on the content of postnatal care received in health facilities located in Kenya and Swaziland against a gold standard of direct observation by a trained third party. We calculated sensitivity, specificity and the area under the receiver operating curve (AUC) to assess individual-level reporting accuracy and the inflation factor (IF) to assess population-level accuracy. We also examined whether women’s reporting accuracy varied significantly by her sociodemographic characteristics.

Results

18 indicators in Kenya and 19 in Swaziland had sufficient sample size for analysis. Of these, 12 indicators in Kenya and five in Swaziland met criteria for acceptable individual and population-level reporting accuracy. Two indicators met acceptability criteria in both Kenya and Swaziland: whether the provider performed a breast exam or an abdominal exam. There was no significant association between women’s characteristics and reporting accuracy, across indicators.

Conclusion

Women are able to accurately report on multiple aspects of care received during a postnatal visit. Findings inform the recommendation of indicators for tracking progress of critical postnatal care interventions for mothers and newborns. Improved measurement of the coverage of maternal and newborn postnatal care is warranted to monitor progress in maternal and newborn care globally.

Assessing the validity of indicators of the quality of maternal and newborn health care in Kenya

BACKGROUND

The measurement of progress in maternal and newborn health often relies on data provided by women in surveys on the quality of care they received. The majority of these indicators, however, including the widely tracked "skilled attendance at birth" indicator, have not been validated. We assess the validity of a large set of maternal and newborn health indicators that are included or have the potential to be included in population-based surveys.

METHODS

We compare women's reports of care received during labor and delivery in two Kenyan hospitals prior to discharge against a reference standard of direct observations by a trained third party (n = 662). We assessed individual-level reporting accuracy by quantifying the area under the receiver operating curve (AUC) and estimated population-level accuracy using the inflation factor (IF) for each indicator with sufficient numbers for analysis.

FINDINGS

Four of 41 indicators performed well on both validation criteria (AUC>0.70 and 0.75<IF<1.25). These were: main provider during delivery was a nurse/midwife, a support companion was present at birth, cesarean operation, and low birthweight infant (<2500 g). Twenty-one indicators met acceptable levels for one criterion only (11 for AUC; 9 for IF). The skilled birth attendance indicator met the IF criterion only.

INTERPRETATION

Few indicators met both validation criteria, partly because many routine care interventions almost always occurred, and there was insufficient variation for robust analysis. Validity is influenced by whether the woman had a cesarean section, and by question wording. Low validity is associated with indicators related to the timing or sequence of events. The validity of maternal and newborn quality of care indicators should be assessed in a range of settings to refine these findings.

Observation of Oscillatory Radial Electric Field Relaxation in a Helical Plasma

Measurements of the relaxation of a zonal electrostatic potential perturbation in a nonaxisymmetric magnetically confined plasma are presented. A sudden perturbation of the plasma equilibrium is induced by the injection of a cryogenic hydrogen pellet in the TJ-II stellarator, which is observed to be followed by a damped oscillation in the electrostatic potential. The waveform of the relaxation is consistent with theoretical calculations of zonal potential relaxation in a nonaxisymmetric magnetic geometry. The turbulent transport properties of a magnetic confinement configuration are expected to depend on the features of the collisionless damping of zonal flows, of which the present Letter is the first direct observation.

Can surveys of women accurately track indicators of maternal and newborn care? A validity and reliability study in Kenya

Background

Tracking progress on maternal and newborn survival requires accurate information on the coverage of essential interventions. Despite widespread use, most indicators measuring maternal and newborn intervention coverage have not been validated. This study assessed the ability of women delivering in two Kenyan hospitals to recall critical elements of care received during the intrapartum and immediate postnatal period at two time points: hospital discharge and 13–15 months following delivery.

Methods

Women’s reports of received care were compared against observations by trained third party observers. Indicators selected for validation were either currently in use or have the potential to be included in population–based surveys. We used a mixed–methods approach to validate women’s reporting ability. We calculated individual–reporting accuracy using the area under the receiver operating curve (AUC), population–level accuracy using the inflation factor (IF), and compared the accuracy of women’s reporting at baseline and follow–up. We also assessed the consistency of women’s reporting over time. We used in–depth interviews with a sub–set of women (n = 20) to assess their understanding of key survey terms.

Results

Of 606 women who participated at baseline and agreed to follow–up, 515 were re–interviewed. Thirty–eight indicators had sufficient sample size for validation analysis; ten met criteria for high or moderate reporting accuracy (0.60<AUC) alone and ten met criteria for low population–level bias alone (0.75<IF<1.25). There was a significant decline in the individual level reporting accuracy between baseline and follow–up for ten indicators. Seven indicators had moderate or higher (0.4≤r_phi) consistency between self–reports at baseline and follow–up. Four indicators met all criteria at follow–up: support person was present during the birth, episiotomy, caesarean section, and low birthweight infant (<2500 g).

Conclusion

The few indicators that women reported accurately at baseline were consistently recalled with accuracy at 13–15 months follow–up. Although there is deterioration in women’s recall in some indicators over time, the extent of deterioration does not appreciably compromise reporting accuracy for indicators with high baseline validity. Indicators related to initial client assessment and the immediate postnatal period have generally low accuracy and poor reporting consistency over time.

Identifying inequities in maternal and child health through risk stratification to inform health systems strengthening in Northern Togo

OBJECTIVE

In Togo, substantial progress in maternal and child health is needed to reach global development goals. To better inform clinic and community-based health services, this study identifies factors associated with maternal and child health care utilization in the Kara region of Northern Togo.

METHODS

We conducted a population-representative household survey of four health clinic catchment areas of 1,075 women of reproductive age in 2015. Multivariable logistic regression was used to model individual and structural factors associated with utilization of four maternal and child health services. Key outcomes were: facility-based delivery, maternal postnatal health check by a health professional within the first six weeks of birth, childhood vaccination, and receipt of malaria medication for febrile children under age five within 72 hours of symptom onset.

RESULTS

83 percent of women who gave birth in the last 2 years delivered at a health facility. In adjusted models, the strongest predictor of facility delivery in the rural catchment areas was proximity to a health center, with women living under three kilometers having 3.7 (95% CI 1.7, 7.9) times the odds of a facility birth. Only 11 percent of women received a health check by a health provider at any time in the postnatal period. Postnatal health checks were less likely for women in the poorest households and for women who resided in rural areas. Children of polygamous mothers had half the odds of receiving malaria medication for fever within 72 hours of symptom onset, while children with increased household wealth status had increased odds of childhood vaccination and receiving treatment for malaria.

CONCLUSION

Our analysis highlights the importance of risk stratification analysis to inform the delivery and scope of maternal and child health programs needed to reach those with the least access to care.

Tracer-Encapsulated Solid Pellet (TESPEL) injection system for the TJ-II stellarator

A tracer-encapsulated solid pellet (TESPEL) injection system for the TJ-II stellarator was recently developed. In order to reduce the time and cost for the development, we combined a TESPEL injector provided by National Institute for Fusion Science with an existing TJ-II cryogenic pellet injection system. Consequently, the TESPEL injection into the TJ-II plasma was successfully achieved, which was confirmed by several pellet diagnostics including a normal-incidence spectrometer for monitoring a tracer impurity behavior.

Measuring progress in maternal and newborn health care in Mexico: validating indicators of health system contact and quality of care

BACKGROUND

The majority of births in Mexico take place in a health facility and are attended by a skilled birth attendant, yet maternal mortality has not declined to anticipated levels. Coverage estimates of skilled attendance and other maternal and newborn interventions often rely on women's self-report through a population-based survey, the accuracy of which is not well established.

METHODS

We used a facility-based design to validate women's report of skilled birth attendance, as well as other key elements of maternal, newborn intrapartum, and immediate postnatal care. Women's reports of labor and delivery care were collected by exit interview prior to hospital discharge and were compared against direct observation by a trained third party in a Mexican public hospital (n = 597). For each indicator, validity was assessed at the individual level using the area under the receiver operating curve (AUC) and at the population level using the inflation factor (IF).

RESULTS

Five of 47 indicators met both validation criteria (AUC > 0.60 and 0.75 < IF < 1.25): urine sample screen, injection or IV medication received during labor, before the birth of the baby (i.e., uterotonic for either induction or augmentation of labor), episiotomy, excessive bleeding, and receipt of blood products. An additional 9 indicators met criteria for the AUC and 18 met criteria for the IF. A skilled attendant indicator had high sensitivity (90.1 %: 95 % CI: 87.1-92.5 %), low specificity (14.0 %: 95 % CI: 5.8-26.7 %) and was suitable for population-level estimation only.

CONCLUSION

Women are able to give valid reports on some aspects of the content of care, although questions regarding the indication for interventions are less likely to be known. Questions that include technical terms or refer to specific time periods tended to have lower response levels. A key aspect of efforts to improve maternal and newborn health requires valid measurement of women's access to maternal and newborn health interventions and the quality of such services. Additional work on improving measurement of population coverage indicators is warranted.

Upgrade of the neutral particle analyzers for the TJ-II stellarator

The TJ-II stellarator, a magnetically confined plasma device, is equipped with a broad range of diagnostics for plasma characterization. These include 4 neutral particle analyzers (NPAs), consisting of two Acord-12's, to perform poloidal measurements, plus a compact NPA, and an Acord-24, these in tangential viewing positions. The Acord-12's were originally equipped with two rows of 6 channels each, one for hydrogen neutrals and the other for deuterium neutrals but were changed to a single row of 12 detectors for hydrogen, the principal working gas in TJ-II. With this upgrade the resultant improved energy resolution spectrum has allowed more reliable ion temperature estimates to be obtained. Here we present the upgrades undertaken and present results to demonstrate the improved performance of this diagnostic.

Impurity temperature correction factors for the transmission grating spectrometer in the TJ-II stellarator

Impurity ion temperature and velocity profiles are obtained across plasmas in the TJ-II stellarator by performing charge-exchange recombination spectroscopy with a diagnostic neutral beam injector. For this, a tridirectional (toroidal plus two poloidal opposing views) multichannel spectroscopic diagnostic, incorporating 12-way fiber arrays, a compact f/1.8 spectrograph, and a back-illuminated CCD, permits Doppler line shifts and widths (of the C VI line at 529.05 nm) to be determined with 1-2 cm spatial resolution. For good photon counting statistics under Li-coated wall conditions, 600 μm diameter fibers collect and transmit light to curved 100 μm wide input slits. When calibrated with a neon pencil lamp this entrance slit width results in a non-Gaussian instrumental function that, if not handled correctly, can result in systematically underestimated impurity temperatures. Here we develop and present correction factors for this effect for a range of conditions.

Regulation of the nicotinic receptor alpha7 subunit by chronic stress and corticosteroids

The alpha7 subunit of the nicotinic acetylcholine receptor (NAchRalpha7) is one of the principal brain receptors for nicotine and is thought to be a mediator of nicotine's pro-cognitive effects. While nicotine is known to interact with the stress axis, little is known about the effect of stress or corticosteroids on the expression in the hippocampus, a brain region important to both cognition and stress reactivity. We examined the effects of chronic (21 day) restraint stress (CRS) and adrenalectomy with hormone replacement with the selective mineralocorticoid receptor (MR) agonist aldosterone, the selective glucocorticoid receptor (GR) agonist RU28,362 or corticosterone for 7 days, on the hippocampal expression of NAchRalpha7 mRNA and protein, as measured by (125)I alpha-Bungarotoxin autoradiography. We found that CRS increased the levels of NAchRalpha7 mRNA in the CA1, CA3 and dentate gyrus while levels of the protein were lowered by the same treatment. Corticosteroid replacement showed a GR specific increase in NAchRalpha7 mRNA, consistent with a corticosteroid mediated effect of CRS. While the mechanism behind these observations is as yet unclear, they may be neuroprotective against the damaging effects of CRS or an example of adaptation to the allostatic load produced by CRS.

A compact flexible pellet injector for the TJ-II stellarator

A compact pellet injector is being built for the TJ-II stellarator. It is an upgraded version of the "pellet injector in a suitcase" developed at Oak Ridge National Laboratory and installed on the Madison Symmetric Torus where it continues to be used in many plasma experiments. The design aim is to provide maximum flexibility at minimal cost, while allowing for future upgrades. It is a four-barrel system equipped with a cryogenic refrigerator for in situ hydrogen pellet formation, a combined mechanical punch/propellant valve system, pellet diagnostics, and an injection line, destined for use as an active diagnostic and for fueling. In order to fulfill both objectives it will be sufficiently flexible to permit pellets, with diameters from 0.4 to 1 mm, to be fabricated and accelerated to velocities from 150 to approximately 1000 m s(-1).

The response of a radiation resistant ceramic scintillator (Al2O3:Cr) to low energy ions (0-60 keV)

This work extends a previous study on ionoluminescence of a radiation-hard ceramic scintillator, Al(2)O(3):Cr, to ions accelerated to keV energies [K. J. McCarthy et al., J. Nucl. Mater. 321, 78 (2003)]. It is motivated by the identification of this material as a promising candidate for use in the fast-ion-loss detector for ITER [for the range of thermal (low energy) and suprathermal ions]. In the paper we quantify and compare its ionoluminescence with that of some common luminescent materials (YAG:Ce and ruby) when irradiated by H(+) ions accelerated to < or = 60 keV using a purpose built laboratory setup. Next, studies are made on the ceramic to quantify its response as a function of incident ion mass, i.e., to He(+). For this, the absolute luminosities of the material are estimated in terms of the number of photons emitted per incident ion as a function of energy. Moreover, the radiation hardness and postirradiation recovery of the ceramic are investigated. Finally, from the studies it can be concluded that the ceramic ruby is a good candidate for detecting low energy ions as long as its temporal response (approximately several milliseconds) is not a constraint for specific ion measurements.

Acquisition of the Temporal and Ordinal Structure of Movement Sequences in Incidental Learning

We investigated the acquisition and integration of temporal and ordinal sequence information in an incidental learning model of motor skill acquisition (the serial reaction time task). Human participants were exposed to a stimulus-response sequence that had temporal structure, ordinal structure, or both. By changing the temporal or ordinal structure, or both, we were able to ask two questions: first, does a regular temporal structure facilitate learning of an ordinal sequence and second, is a temporal sequence, presented in the context of a random ordinal sequence of finger movements, “picked up” through incidental learning? We found that a predictable temporal structure greatly facilitated the learning of an ordinal sequence but was not learned when presented in isolation. The results suggest that when motor skills are acquired under incidental learning conditions, timing is represented at a level specific to the ordinal sequence of movements rather than as an independent temporal template.

Leprecan distribution in the developing and adult kidney

The temporal and spatial deposition of extracellular matrix proteins is critical for nephrogenesis and glomerular maturation. We previously characterized leprecan as a novel chondroitin sulfate proteoglycan which has been recently shown to have prolyl hydroxylase activity. In this study, we examine the distribution of leprecan during nephrogenesis and after a hypertrophic stimulus to the adult kidney. During development, leprecan was localized to mesenchymal aggregates, early comma- and S-phase structures as determined by immunohistochemistry and in situ hybridization. Leprecan mRNA was increased in cells around the vascular cleft of the S- and comma-phase glomeruli. Expression was found in podocytes, mesangial cells, and parietal epithelial cells of loop-phase glomeruli. Leprecan mRNA was substantially decreased in the glomeruli of the adult kidney compared to the developing kidney with a uniform distribution between the glomeruli and the tubules. Within adult glomeruli, leprecan was found in the mesangium mesangial matrix, podocytes, and in Bowman's capsule. In response to glomerular hypertrophy, produced by unilateral nephrectomy, leprecan synthesis was increased in the adult kidney. We suggest that the regulated expression of leprecan during glomerular development or hypertrophy coupled with its reported prolyl hydroxylase activity plays a role during basement membrane assembly.

The growth of chondrocytes into a fibronectin-coated biodegradable scaffold

Porous scaffolds made from a biodegradable copolymer of trimethylene carbonate and glycolide were evaluated for tissue-engineered medical products. We examined the scaffold coated with cell adhesion protein and fibronectin and cultured under a dynamic mixing condition to enhance the growth of chondrocytes. Our hypothesis was that the combination of coating and dynamic mixing would be beneficial to the viability of the chondrocytic cells. Fibronectin was selected as the model protein because of its availability and routine assaying methods. Sterile samples of scaffolds of about 1 mm in thickness were coated with fibronectin at 37 degrees C for 1.5 h. Four groups of scaffolds were used: uncoated static or dynamic, and coated static or dynamic. Scaffold samples were placed in either a Petri dish or a spinner flask (static vs. dynamic groups) after inoculation with rat chondrocytes of an initial cell density of 1.29 x 10(5) cell/mL. After 7, 14, 21, and 28 days, each sample was fixed, embedded, and sectioned at 5 micro thickness. The sections were double-label immunostained using antibodies against cellular fibronectin synthesized by adherent cells as a measure of cell viability. A Hoechst 33258 nuclear stain was used to measure the number of cells attached to the scaffold at each time interval. The slides were examined using a fluorescence microscope to determine the cell ingrowth. At least 25 fields/treatment group (except the 7 day group) were measured. The data showed that cell in-growths into the porous scaffolds were higher at all time periods for the coated dynamic group than those for the other three groups.

Troglitazone halts diabetic glomerulosclerosis by blockade of mesangial expansion

BACKGROUND

Renal complications of long-term, poorly controlled type 2 diabetes mellitus include glomerulosclerosis and interstitial fibrosis. The onset and progression of these complications are influenced by underlying pathophysiologies such as hyperglycemia, hypertriglyceridemia, and hypercholesterolemia. Troglitazone, a thiazolidinedione, has been shown to ameliorate these metabolic defects. However, it was not known whether therapeutic intervention with troglitazone would prevent the onset and progression of glomerulosclerosis.

METHODS

Sixty male ZDF/Gmitrade mark rats and 30 age-matched Zucker lean rats were in the study. The ZDF/Gmitrade mark rats were divided into two groups, one in which blood glucose levels were uncontrolled (30 animals) and another (30) in which blood glucose was controlled via dietary administration of troglitazone. Ten animals from each group were sacrificed at one, three, and six months into the study. The kidneys were harvested and processed for immunostaining with BM-CSPG, a marker for mesangial matrix. Images of 200 glomeruli per animal were captured using digital imaging microscopy, and the index of mesangial expansion (total area mesangium/total area of tuft) per glomerular section was measured.

RESULTS

The administration of troglitazone ameliorated the metabolic defects associated with type 2 diabetes mellitus. Moreover, the glomeruli from tissue sections of animals given troglitazone showed no mesangial expansion when compared with normoglycemic control animals, whereas the uncontrolled diabetic animals showed significant mesangial expansion at all time intervals.

CONCLUSIONS

Therapeutic intervention with the thiazolidinedione troglitazone halts the early onset and progression of mesangial expansion in the ZDF/Gmitrade mark rat, preventing the development of glomerulosclerosis in this animal model of type 2 diabetes mellitus.

A study of the response of Y3Al5O12:Ce phosphor powder screens in the vacuum ultraviolet and soft X-ray regions using synchrotron radiation

Phosphor screens find application in many fields because of their ability to convert incident radiation to wavelengths that are readily measured by modern detectors. While the response of such screens in the X-ray region has been widely studied, much work still remains to be done regarding their response in the vacuum ultraviolet and soft X-ray regions, where the response is predicted to be non-linear owing to the presence of elemental absorption edges. Here, an experiment using synchrotron radiation to determine the response of thin Y(3)Al(5)O(12):Ce (1-21 mg cm(-2)) and Y(2)O(3):Eu (2.64 mg cm(-2)) powder phosphor screens in the spectral range 20-900 A (13.8-620 eV) is reported. Also, a custom-built camera is described which permits simultaneous collection of the forward- and backward-emitted light and that enables measurements to be made at various positions across the screens and at several screen/incident beam angles. Finally, features in the response spectra are identified, and efficiencies across the spectral range indicated for different screen thicknesses and operating modes are plotted, before a curve of the intrinsic radiant efficiency of Y(3)Al(5)O(12):Ce is produced. The results are discussed in the context of other measurements.

Gap junctions in human synovial cells and tissue

Our objective was to establish the existence of intercellular communication through gap junctions in synovial lining cells and in primary and passaged cultures of human synovial cells. Communication between cells was assessed using the nystatin perforated-patch method, fluorescent dye transfer, immunochemistry, transmission electron microscopy, and immunoblotting. Functional gap junctions were observed in primary and passaged cultures and were based on measurements of the transient current response to a step voltage. The average resistance between cells in small aggregates was 300 +/- 150 MOmega. Gap junctions were also observed between synovial lining cells in tissue explants; the size of the cell network in synovial tissue was estimated to be greater than 40 cells. Intercellular communication between cultured cells and between synovial lining cells was confirmed by dye injection. Punctate fluorescent regions were seen along intercellular contacts between cultured cells and in synovial membranes in cells and tissue immunostained for connexin43. The presence of the protein was verified in immunoblots. Regular 2-nm intermembrane gap separations characteristic of gap junctions were seen in transmission electron micrographs of synovial biopsies. The results showed that formation of gap-junction channels capable of mediating ionic and molecular communication was a regular feature of synovial cells, both in tissue and in cultured cells. The gap junctions contained connexin43 protein and perhaps other proteins. The physiological purpose of gap junctions in synovial cells is unknown, but it is reasonable to anticipate that intercellular communication serves some presently unrecognized function.

Basement membrane chondroitin sulfate proteoglycan and vascularization of the developing mammalian limb bud

We used immunocytochemistry to study the basement membrane-chondroitin sulfate proteoglycan (BM-CSPG) distribution in mammalian limb bud and its relationship to and possible role in limb development. Anti-BM-CSPG immunostaining was examined in the developing limb buds of 24 Sprague-Dawley rats at embryonic days 12 to 14 and 19. BM-CSPG immunostaining was present in 3 regions. The first region was located peripherally in the limb bud ectodermal basement membrane (BM) that separates ectoderm from mesoderm and was present at all embryonic stages examined. The second region was in the mesenchymal extracellular matrix independent of the vascular system. This staining pattern was diffuse, granular, and often homogeneous, except for clustering adjacent to developing vessels, and was observed distally in the limb bud. In the mesenchymal extracellular matrix adjacent to the distal BM this staining pattern formed fibrils that were perpendicular and connected to the limb bud BM and extended into the underlying mesenchyme. The third region was localized to the BM of developing blood vessels of the limb bud. Blood vessel staining allowed analysis of limb bud vessel formation. The early developing blood vessels at the proximal limb bud were organized differently from those located distally. Large central vessels were present proximally, whereas a rich plexus of smaller vascular channels was present at the distal margin. A subectodermal avascular zone was observed at the margin of the limb bud, except beneath the apical ectodermal ridge where immunostained blood vessels extended from the distal vascular plexus toward the apical ectodermal ridge. The formation of central larger vessels occurs proximally, whereas formation of peripheral smaller vessels seems to take place locally and distally under the influence of the apical ectodermal ridge. BM-CSPG plays an important role in blood vessel formation and mammalian limb bud development. (J Hand Surg 2000; 25A:150-158.

Molecular characterization of a novel basement membrane-associated proteoglycan, leprecan

A monoclonal antibody was used in early studies to identify a novel chondroitin sulfate proteoglycan, secreted by L-2 cells, the core protein of which was approximately 100 kDa. To characterize this proteoglycan core protein at the molecular level, an L-2 cell cDNA library was probed by expression screening and solution hybridization. Northern blot analysis assigned transcript size to approximately 3.1 kilobases and, after contig assembly, the coding region of the mRNA corresponded to 2.18 kilobases. Immunoassays were performed to confirm the identity of this sequence, using a polyclonal antibody raised against an expressed fusion protein encoded by sequence representing the carboxyl half of the molecule. The antibody recognized the core protein in Western blots after prior digestion of the intact proteoglycan with chondroitinase ABC. Immunostaining tissue sections with the same antibody localized the proteoglycan to basement membranes, and expression of the entire sequence in Chinese hamster ovary K-1 cells showed that the protein encoded by the sequence secreted as a chondroitin sulfate proteoglycan. The core protein not only has motifs permitting glycosylation as a proteoglycan, but also possesses the endoplasmic reticulum retrieval signal, KDEL, which suggests that, in addition to its role as a basement membrane component, it may also participate in the secretory pathway of cells.

Peer reviewed: environmental forensics unraveling site liability

An interdisciplinary analytical approach can unravel environmental liability at contaminated sites.

Morphogenesis of the glomerular filter: the synchronous assembly and maturation of two distinct extracellular matrices

The morphogenesis of the glomerular filtration apparatus during pre- and postnatal development in the rodent involves the coordinated assembly of two closely apposed but morphologically different extracellular matrices, the glomerular capillary basement membrane and the mesangial matrix. The cellular origin of these matrices is known to be distinct and complex; however, the mechanisms by which these matrices are assembled during morphogenesis are not entirely understood. It has been shown that in the earliest stages of glomerular morphogenesis the nascent glomerular basement membrane exists as a four-layered structure, the product of both the visceral epithelium and capillary endothelium. During the latter stages of glomerular development, the quadrilaminar structure becomes a trilaminar basement membrane, the event thought to occur by fusion of closely apposed basement membrane layers. In subsequent stages of maturation and throughout the life of the animal, the visceral epithelial cells, which line the periphery of the glomerular capillary, are the primary source of newly synthesized basement membrane material. The mesangial matrix, which lacks the specific organization of a basement membrane, first occurs in the developing glomerulus as a diffuse matrix central to the developing glomerular capillaries. During glomerular maturation the mesangial matrix undergoes a compaction/arborization coincident with the ramification of the vascular histoarchitecture of the glomerular tuft. Recent advances in the cell biology of basement membrane now demonstrate that there is a divergence in isoforms of the molecules that comprise the glomerular capillary basement membrane and mesangial matrices during development, possibly coincidental with functional specialization during the process of glomerular maturation.

A human resource planning model for hospital/medical technologists: an analytic hierarchy process approach

This paper deals with the development of a human resource planning (HRP) model for hospital laboratory personnel. External and organizational factors impacting the demand and supply of clinical laboratory personnel in an urban academic health center are identified by a Delphi process. These factors are structured into a hierarchy for the application of the Analytic Hierarchy Process (AHP). Computer software, Expert Choice, was used in model hierarchy development and judgmental elicitation process. The model result can be applicable to eliciting the perceptions, insights, and understanding of health-care decision-makers for strategic human resource planning.

The X-Ray CCDs Developed for the Joint European X-Ray Telescope

The charge coupled devices (CCDs) developed for the Joint European X-ray Telescope (JET-X) are described in detail. A history of the development program and device performance is given. We present results from a comprehensive study to characterize the x-ray response of the flight model focal plane detectors. The goal of the program is to calibrate the efficiency, energy resolution, gain, etc. down to a precision of ~1%. Final calibration data sets will be based on combinations of measurements and calculations. For example, the CCD quantum efficiency will be composed of discrete line measurements made at the University of Leicester test facility and calculation and synchrotron measurements from the Daresbury Synchrotron Radiation Source (SRS). The absolute normalizations will be provided by x-ray long beam pipe measurements at the Max Planck Institut für Extraterrestrische Physik (MPE) Panter test facility in Munich. Using the available data, it is shown that it is possible to calibrate the quantum efficiency, the FWHM energy resolution, and the system gain of the flight devices to better than 1%.

Rat mesangial cells in vitro synthesize a spectrum of proteoglycan species including those of the basement membrane and interstitium

Accumulation of extracellular matrix within the mesangium is an important event in the development of glomerular disease. In this report we have used indirect immunofluorescence to positively identify a number of constituents of the mesangial matrix synthesized by rat mesangial cells (RMC) in vitro including laminin, fibronectin, type IV collagen and the basement membrane heparan sulphate proteoglycan (BM-HSPG) known as perlecan. In addition, using Mab 2B5 we demonstrate that RMC synthesize a specific basement membrane chondroitin sulfate (BM-CSPG), a matrix component that in normal animals is localized in the mesangium but is not found in the pericapillary glomerular basement membrane (GBM). Further characterization of the proteoglycans synthesized by RMC in vitro revealed: (i) a second large CSPG, identified as versican; (ii) two small dermatan sulphate proteoglycans identified as biglycan and decorin, which together account for the majority of the proteoglycans; (iii) a large HSPG-I, probably related to perlecan; and (iv) a small HSPG-II. The cell layer proteoglycans can be sub-divided into a class that are probably free in the membrane, and a class of anchored molecules of the extracellular matrix or stabilized by cytoskeletal elements.

Targeting of transforming growth factor-alpha expression to pituitary lactotrophs in transgenic mice results in selective lactotroph proliferation and adenomas

The PRL-secreting cells of the pituitary gland normally express transforming growth factor-alpha (TGF alpha). To determine the effect of increasing TGF alpha expression in the pituitary, a transgenic mouse model was created in which overexpression of human TGF alpha was directed to the pituitary lactotrophs using the rat PRL promoter. Of the four gene-positive mouse lines, two expressed the messenger RNA corresponding to the transgenic in the pituitary glands. However, in both these lines, expression could only be detected in the female animals. Expression of the transgenic could be detected as early as 1 month of age, but no pathology or developmental abnormalities were detected until the animals reached 6 months, at which time, hyperplasia of the lactotrophs. By the age of 12 months, all of the homozygous transgenic females had developed pituitary adenomas that were immunopositive for PRL. The other hormone-producing cells of the pituitary showed no obvious pathology. The male transgenics developed neither hyperplasia nor adenomas, nor did the gene-positive transgenic lines that did not express the transgene. In no case was an aggressive pituitary tumor seen. This transgenic mouse model indicates that TGF alpha overexpression by lactotrophs stimulates the growth of these pituitary cells. Furthermore, TGF alpha has a highly localized action in the pituitary gland, resulting only in lactotroph hyperplasia and prolactinomas. These observations suggest that TGF alpha might play a role in the development of prolactinomas.

Basement membrane-specific chondroitin sulfate proteoglycan is abnormally associated with the glomerular capillary basement membrane of diabetic rats

We have previously reported the production of monoclonal antibodies (MAb) recognizing the core protein of a basement membrane-specific chondroitin sulfate proteoglycan (BM-CSPG). Using immunohistochemical techniques, we have shown that BM-CSPG is present in almost every basement membrane, one exception being the normal glomerular capillary basement membrane (GBM), where it is absent. In the present study of mature kidneys we examined the distribution of BM-CSPG in streptozocin-induced diabetes mellitus in rats. We found BM-CSPG atypically associated with the GBM of diabetic animals as early as 1 month after induction of diabetes mellitus. Immunoelectron microscopy (IEM) of affected capillary loops showed BM-CSPG present in the subendothelial matrix in areas of GBM thickening and absent in areas where the GBM appears to be of normal thickness. Moreover, the association of BM-CSPG with regions of the pericapillary GBM affects the morphology of the capillary endothelial cells within these areas, directly displacing the cell body from the GBM proper and causing loss of fenestrae. These new data on BM-CSPG distribution reflect abnormal glomerular extracellular matrix protein biosynthesis/turnover in diabetes and suggest that BM-CSPG in the GBM might in turn affect normal capillary structure and/or function.

Basement membrane chondroitin sulfate proteoglycan alterations in a rat model of polycystic kidney disease

Alterations in basement membrane components, notably proteoglycans, in a rat model of polycystic kidney disease have been investigated. Rats were fed phenol II (2-amino-4-hydroxyphenyl-5-phenyl thiazole) for 4 days and then changed to normal diet for a 7-day recovery period. Marked dilation of distal tubules and collecting ducts was observed by 4 days with phenol II treatment, but the morphology returned to normal after 7 days of subsequent normal diet. Staining of tissue sections with two mouse monoclonal antibodies to a recently described basement membrane chondroitin sulfate proteoglycan (BM-CSPG) core protein was markedly diminished in the basement membranes of dilated cystic tubules. Reduction in staining was evident as early as 2 days. During recovery, BM-CSPG increased in tubular basement membranes and returned to normal after 7 days. Staining with a polyclonal antibody to chondroitin sulfate chains confirmed these changes in cystic tubule basement membranes. During the recovery stage, interstitial chondroitin sulfate (representing a CSPG other than BM-CSPG) was greatly increased around these tubules, along with the glycoprotein fibronectin. Staining with antibody to a basement membrane heparan sulfate proteoglycan core protein related to perlecan did not diminish but rather stained affected tubules intensely, whereas laminin, on the other hand, was apparently diminished in the basement membranes of the cystic tubules. Type IV collagen staining did not change through disease onset or recovery. These results suggest that BM-CSPG, which was rapidly altered in distribution through the onset and recovery phases, may be a sensitive marker of the cystic state, and in addition, the expression of basement membrane proteoglycans may be specifically and separately regulated in this disease.

Glomerular matrix: synthesis, turnover and role in mesangial expansion

The extracellular matrix has an integral role in development, homeostasis and pathology of the glomerulus. Three spatially distinct matrices are present in the glomerulus: the mesangium, and basement membranes of the capillary loops and Bowman's capsule. Each is dominated by basement membrane components, but is distinct in organization and composition. Many matrix components influence cell behavior directly, through specific interactions with receptors, or indirectly through growth factor sequestration. Growth factors may be of great importance in development and disease progression in the glomerulus, and may be central to mesangial expansion. In addition, changes in matrix composition accompany and contribute to the pathological condition, such as the accumulation of matrix in diabetes mellitus.

Coarctation induces alterations in basement membranes in the cardiovascular system

A coarctation hypertensive rat model was used to examine the effects of elevated blood pressure on basement membrane component synthesis by cardiac myocytes and aorta using immunohistochemistry and Northern blot analysis. Carotid arterial pressure increased immediately on coarctation, and left ventricular hypertrophy was maximal within 5 days. In immunohistochemical studies, fibronectin and laminin were increased and the basement membrane chondroitin sulfate proteoglycan decreased in both the subendothelial space and smooth muscle cell basement membranes of the aorta above the clip compared with controls, whereas only fibronectin was elevated in the aorta below the clip. No change in basement membrane staining intensity for the cardiac myocytes was observed. Alterations in steady-state mRNA levels for fibronectin and laminin in the aorta paralleled those observed by immunohistochemical analysis with regard to protein and tissue type affected as well as intensity of the changes. However, changes in mRNA levels (but not protein deposition) for perlecan and type IV collagen were also observed in aortas from hypertensive rats compared with controls. Increases in steady-state mRNA levels for all basement membrane components in the heart and vasculature peaked before maximal cardiac hypertrophy (5 days). These studies indicate that alterations in basement membrane component deposition in the hypertrophied vasculature occur at both transcriptional and translational levels and suggest that the cell attachment glycoproteins fibronectin and laminin may be important factors in the vascular response to elevated transmural pressure.

Immunohistochemical localization of chondroitin sulfate, chondroitin sulfate proteoglycan, heparan sulfate proteoglycan, entactin, and laminin in basement membranes of postnatal developing and adult rat lungs

Histologic preparations of lungs from 1-, 5-, 10-, 18-, and 25-day-old postnatal and adult rats were examined immunohistochemically with antibodies specific against chondroitin sulfate (CS), basement membrane chondroitin sulfate proteoglycan (BM-CSPG), heparan sulfate proteoglycan (HSPG), entactin, and laminin. A monoclonal antibody specific for the glycosaminoglycan portion (CS) of CSPG and a monoclonal antibody against the core protein of CSPG were used in an immunoperoxidase sequence to stain extracellular matrix (ECM) components of pulmonary basement membranes (BMs). Anti-CS stained airway BM strongly and alveolar BM weakly in the adult rat lung, as well as in vascular and airway adventitia. In developing lungs, immunoreactivity was strong in all ECM sites, including BM, at day 1 postnatal, and progressively diminished thereafter except in vascular and airway adventitia. Anti-CSPG stained alveolar, airway, and vascular BMs, in addition to smooth muscle external laminae (EL), in the adult and developing rat. Immunostaining for CSPG required hyaluronidase digestion, whereas CS staining was lost with the same treatment. A polyclonal antibody to the core protein of HSPG was found to be similarly distributed to CSPG by immunoperoxidase staining in adult and developing rat lungs, with the notable exception that little immunoreactivity for HSPG was found in smooth muscle EL. Commercially obtained polyclonal antibodies to entactin and laminin gave immunostaining comparable to that seen with CSPG, except that entactin showed particular affinity for EL. These results offer a more detailed perspective on previous survey observations of CSPG, HSPG, and entactin in the rat lung, and describe the immunoreactivity of CS for the first time.(ABSTRACT TRUNCATED AT 250 WORDS)

Basement membrane proteoglycans in glomerular morphogenesis: chondroitin sulfate proteoglycan is temporally and spatially restricted during development

We previously reported the presence of a basement membrane-specific chondroitin sulfate proteoglycan (BM-CSPG) in basement membranes of almost all adult tissues. However, an exception to this ubiquitous distribution was found in the kidney, where BM-CSPG was absent from the glomerular capillary basement membrane (GBM) but present in other basement membranes of the nephron, including collecting ducts, tubules, Bowman's capsule, and the glomerular mesangium. In light of this unique pattern of distribution and of the complex histoarchitectural reorganization occurring during nephrogenesis, the present study used light and electron microscopic immunohistochemistry to examine the distribution of BM-CSPG and basement membrane heparan sulfate proteoglycan (BM-HSPG) during prenatal and postnatal renal development in the rat. Our results show that the temporal and spatial pattern of expression of BM-CSPG during nephrogenesis is unlike that reported for other basement membrane components such as laminin, fibronectin, and BM-HSPG, all of which can be found in the earliest formed basement membranes of the vesicle-stage nephron. Although BM-CSPG is present in the basement membranes of the invading vasculature and ureteric buds, its first appearance in nephron basement membrane occurs during the late comma stage. In capillary loop-stage glomeruli of prenatal animals, BM-CSPG is present in the presumptive mesangial matrix but undetectable in the GBM. However, as postnatal glomerular maturation progresses BM-CSPG is also found in both the lamina rara interna and lamina densa of the GBM in progressively increasing amounts, being most evident in the GBM of 21-day-old animals. Micrographs of glomeruli from 42-day-old animals show that BM-CSPG gradually disappears from the GBM and, by 56 days after birth, appears to be completely absent from the GBM, its pattern of distribution resembling that of the adult animal. Our results show that BM-CSPG is not required for the initial assembly of basement membranes but may in fact serve to stabilize basement membrane structure after histoarchitectural reorganization is completed.

Basement membrane proteoglycans and development

Basement membranes contain distinct collagen, glycoprotein and proteoglycan species, and these exhibit considerable heterogeneity in isoform or type when different tissue types are compared. Additionally, many components are differentially expressed in organogenesis. We have considered the distributions in glomerulogenesis of two distinct basement membrane proteoglycans, a small heparan sulfate proteoglycan and a chondroitin sulfate proteoglycan (BM-CSPG). While the former was present in all kidney basement membranes through development, the latter was apparently regulated in distribution. BM-CSPG was only strongly expressed in the vasculature invading late comma stage glomeruli, and later in presumptive and mature Bowman's capsule. Over the first six to eight weeks, the capillary basement membranes contained BM-CSPG, but in gradually decreasing amounts until it became completely undetectable. The basement membrane of the adult rat glomerulus is unique in its lack of BM-CSPG. However, in diabetic rats, BM-CSPG is apparently re-expressed in the glomerular basement membrane, a potential marker for pathological changes in glomerular structure. While its function awaits elucidation, BM-CSPG may be essential for basement membrane integrity or stability and have important roles in kidney development.

Ultrastructural immunocytochemical localization of chondroitin sulfate proteoglycan in Bruch's membrane of the rat

Two monoclonal antibodies (Mab 4D5 and 2D6) raised against the core protein of a basement membrane chondroitin sulfate proteoglycan from Reichert's membrane of the rat, were used for ultrastructural immunoperoxidase localization of this protein in Bruch's membrane of the rat. Immunoreactivity for both antibodies was found in the basal lamina (basement membrane) of the choriocapillary endothelium and retinal pigment epithelium, in collagen fibers in the collagenous zones, and surrounding the elastic layer.

Co-deposition of basement membrane components during the induction of murine splenic AA amyloid

Past studies have demonstrated that during murine AA amyloid induction there is co-deposition of the AA amyloid peptide and the basement membrane form of heparan sulfate proteoglycan. The synthesis and accumulation of heparan sulfate proteoglycan does not usually occur in the absence of other basement membrane components, such as type IV collagen, laminin, and fibronectin. Using immunohistochemical techniques, the present experiments have demonstrated that in addition to the heparan sulfate proteoglycan, there are other basement membrane components present in splenic AA amyloid deposits and these are present as soon as AA amyloid deposits are detectable. The results indicate that within the time constraints imposed by the experiments, the basement membrane components, fibronectin, laminin, type IV collagen, and heparan sulfate proteoglycan are co-deposited 36 to 48 hours after the AgNO3 and amyloid enhancing factor induction of amyloid, the period when amyloid is first detected. These observations raise the possibility that an abnormality in basement membrane metabolism is a very early event, and potentially plays an integral part in the process of AA amyloidogenesis.

Basement membrane chondroitin sulfate proteoglycans: localization in adult rat tissues

Heparan sulfate proteoglycans have been described as the major proteoglycan component of basement membranes. However, previous investigators have also provided evidence for the presence of chondroitin sulfate glycosaminoglycan in these structures. Recently we described the production and characterization of core protein-specific monoclonal antibodies (MAb) against a chondroitin sulfate proteoglycan (CSPG) present in Reichert's membrane, a transient extra-embryonic structure of rodents. This CSPG was also demonstrated to be present in adult rat kidney. We report here the tissue distribution of epitopes recognized by these MAb. The ubiquitous presence of these epitopes in the basement membranes of nearly all adult rat tissues demonstrates that at least one CSPG is a constituent of most basement membranes, and by virtue of its unique distribution is distinct from other chondroitin and dermatan sulfate proteoglycans previously described.