Death rates in the U.S. due to Leukodystrophies with pediatric forms

To use national mortality and state death certificate records to estimate disease specific mortality rates among pediatric and adult populations for 23 leukodystrophies (LDs) with pediatric forms. Additionally, to calculate yearly prevalence and caseload of the most severe LD cases that will eventually result in pediatric death (i.e., pediatric fatality cases). Death certificate records describing cause of death were collected from states based on 10 ICD-10 codes associated with the 23 LDs. Deaths in the U.S. with these codes were distributed into categories based on proportions identified in state death certificate data. Mortality rates, prevalence, and caseload were calculated from resulting expected numbers, population sizes, and average lifetimes. An estimated 1.513 per 1,000,000 0-17 year old's died of these LDs at average age 5.2 years and 0.194 for those ≥18 at an average age of 42.3 years. Prevalence of pediatric fatality cases of these LDs declined from 1999 through 2007 and then remained constant at 6.2 per million children per year through 2012. Epidemiological information, currently lacking for rare diseases, is useful to newborn screening programs, research funding agencies, and care centers for LD patients. Methods used here are generally useful for studying rare diseases.

Development of a newborn screening tool for mucopolysaccharidosis type I based on bivariate normal limits: Using glycosaminoglycan and alpha-L-iduronidase determinations on dried blood spots to predict symptoms

PURPOSE

Current newborn screening (NBS) for mucopolysaccharidosis type I (MPSI) has very high false positive rates and low positive predictive values (PPVs). To improve the accuracy of presymptomatic prediction for MPSI, we propose an NBS tool based on known biomarkers, alpha-L-iduronidase enzyme activity (IDUA) and level of the glycosaminoglycan (GAG) heparan sulfate (HS).

METHODS

We developed the NBS tool using measures from dried blood spots (DBS) of 5000 normal newborns from Gifu Prefecture, Japan. The tool's predictive accuracy was tested on the newborn DBS from these infants and from seven patients who were known to have early-onset MPSI (Hurler's syndrome). Bivariate analyses of the standardized natural logarithms of IDUA and HS levels were employed to develop the tool.

RESULTS

Every case of early-onset MPSI was predicted correctly by the tool. No normal newborn was incorrectly identified as having early-onset MPSI, whereas 12 normal newborns were so incorrectly identified by the Gifu NBS protocol. The PPV was estimated to be 99.9%.

CONCLUSIONS

Bivariate analysis of IDUA with HS in newborn DBS can accurately predict early MPSI symptoms, control false positive rates, and enhance presymptomatic treatment. This bivariate analysis-based approach, which was developed for Krabbe disease, can be extended to additional screened disorders.

Survey of quality of life, phenotypic expression, and response to treatment in Krabbe leukodystrophy

OBJECTIVES

To develop a quality of life (QOL) survey for Krabbe disease (KD), and to thereby improve understanding of its phenotypic expression and response to treatment.

METHODS

The survey, the Leukodystrophy Quality of Life Assessment (LQLA) and the Vineland Adaptive Behavior Scales were co-administered to 33 patients or their caretakers. These included the phenotypes of early infantile KD (EIKD; 0-6 months old at onset), late infantile cases (LIKD; 7-12 months old at onset), and cases that emerged after 12 months old, late onset (LOKD). The sample included cases with and without stem cell transplantation (SCT). Reliability and concurrent validity were assessed for overall and subscale scores. Analysis of variance tested differences in QOL between phenotypes and transplant groups (none, pre-, post-symptom).

RESULTS

Good concurrent validity with the Vineland was shown for total, communication, daily activity, social, and motor scales and good reliability was observed. LOKD cases had better communication skills than either EIKD or LIKD and better overall QOL than EIKD. Analyses of individual items showed that communication items, mostly, contributed significantly to phenotype differences. Presymptomatic SCT significantly improved QOL compared to postsymptomatic SCT or no treatment. Presymptomatically treated patients had near-normal total scores.

CONCLUSIONS

The LQLA is valid and reliable. Despite small sample size, phenotypic demarcation was determined to be due mainly to differences in communication skills. There was a relative enhancement of QOL in LOKD patients, and in those who had presymptomatic SCT. These results apply to the current controversy about recommendations for newborn screening for this condition.

Squamous Carcinomas of the Head and Neck: Some Patterns of Spread

Patterns of tumour spread are examined in 160 patients with squamous carcinomas of the head and neck with reference to perineural infiltration, direct invasion of bone and ossified cartilage, and lymph node metastases in the previously irradiated neck. Perineural spread is comparatively common in large (T3, T4) tumours; it may be apparent early in the disease; it is often detectable clinically; and it is an adverse prognostic feature which may modify clinical management. Direct bone invasion is described with particular reference to tumours of the oral cavity. Most bone destruction is mediated by osteoclasts which appear to be stimulated by materials such as prostaglandins released in the vicinity of the tumour. The numbers of involved lymph nodes in surgical dissections from the irradiated neck are usually few and restricted to the submandibular and jugular groups; nodes in the posterior triangle are infrequently involved by metastatic carcinoma. Transcapsular spread and keratin granulomas are common. The scope of modified neck dissections in this group of patients is discussed.

Can psychosine and galactocerebrosidase activity predict early-infantile Krabbe's disease presymptomatically?

Krabbe's disease (KD) is a fatal neurodegenerative disorder, with the early-infantile form (EIKD) defined by onset of symptoms before age 6 months. Early and highly accurate identification of EIKD is required to maximize benefits of hematopoietic stem cell transplantation treatment. This study investigates the potential for accurate prediction of EIKD based on a novel newborn screening (NBS) tool developed from two biomarkers, galactocerebrosidase (GALC) enzyme activity and galactosylsphingosine concentration (psychosine [PSY]). Normative information about PSY and GALC, derived from distinct samples of normal newborns, was used to develop the novel diagnostic tool. Bivariate normal limits (BVNL) were constructed, assuming a multivariate normal distribution of natural logarithms of GALC and PSY of normal newborns. The (lnGALC, lnPSY) points for newborns in various "abnormal groups," including one group of infants who subsequently suffered EIKD, were plotted on a graph of BVNL. The points for all EIKD patients fell outside of BVNL (100% sensitivity). In a simulation study to compare the false-positive rate of existing univariate methods of diagnosis with our new BVNL-based method, we generated 100 million normal newborn data points. All fell within BVNL (i.e., zero false positives), whereas 5,682 false positives were observed when applying a two-tiered univariate method of the type suggested in the literature. These results suggest that (lnGALC, lnPSY) BVNLs will allow highly accurate prediction of EIKD, whereas two-tiered univariate approaches will not. Redevelopment of the BVNL based on GALCs and PSYs measured on a common large sample of normal newborns is required for NBS use. © 2016 Wiley Periodicals, Inc.

Evidence for improved survival in postsymptomatic stem cell-transplanted patients with Krabbe's disease

Krabbe's disease (KD) is a severe neurodegenerative disorder affecting white matter in the brain and peripheral nerves. Transplantation of hematopoietic stem cells (HSCT), although not curative, has been shown to extend survival and alleviate neurodevelopmental symptoms when treatment precedes the onset of symptoms. Existing evidence, although not tested statistically, seems clearly to show that postsymptomatic transplantation does not improve neurodevelopmental outcomes. The impact of postsymptomatic HSCT treatment on survival, however, is an open question. This study uses a KD registry to examine the effect of HSCT on survival of symptomatic KD patients. Sixteen transplanted patients were matched by age of onset to 68 nontransplanted patients. The potential confounding effect of age of onset was, therefore, avoided. To quantify the effect of HSCT over time, we used Cox regression analysis, and we observed a sustained and nearly 2.2-fold risk of death from KD in patients who were not transplanted relative to those who were transplanted (one-tailed P = 0.0365; 95% lower bound = 1.07). The improvement of survival resulting from HSCT did not appear to depend on the age of symptom onset. Thus, these results establish a long-term, quantitative benefit of HSCT even in patients who are already experiencing symptoms. They also provide a benchmark for improved survival that can be used for potential new treatments for KD. © 2016 Wiley Periodicals, Inc.

Generalized multiple indicators, multiple causes measurement error models

Generalized Multiple Indicators, Multiple Causes Measurement Error Models (G-MIMIC ME) can be used to study the effects of an unobservable latent variable on a set of outcomes when the causes of the latent variables are unobserved. The errors associated with the unobserved causal variables can be due to either bias recall or day-to-day variability. Another potential source of error, the Berkson error, is due to individual variations that arise from the assignment of group data to individual subjects. In this article, we accomplish the following: (a) extend the classical linear MIMIC models to allow both Berkson and classical measurement errors where the distributions of the outcome variables belong in the exponential family, (b) develop likelihood based estimation methods using the MC-EM algorithm and (c) estimate the variance of the classical measurement error associated with the approximation of the amount of radiation dose received by atomic bomb survivors at the time of their exposure. The G-MIMIC ME model is applied to study the effect of genetic damage, a latent construct based on exposure to radiation, and the effect of radiation dose on physical indicators of genetic damage.

Patient and physician factors associated with participation in cervical and uterine cancer trials: an NRG/GOG247 study

PURPOSE

The aim of this study was to identify patient and physician factors related to enrollment onto Gynecologic Oncology Group (GOG) trials.

METHODS

Prospective study of women with primary or recurrent cancer of the uterus or cervix treated at a GOG institution from July 2010 to January 2012. Logistic regression examined probability of availability, eligibility and enrollment in a GOG trial. Odds ratios (OR) and 95% confidence intervals (CI) for significant (p<0.05) results reported.

RESULTS

Sixty institutions, 781 patients, and 150 physicians participated, 300/780 (38%) had a trial available, 290/300 had known participation status. Of these, 150 women enrolled (59.5%), 102 eligible did not enroll (35%), 38 (13%) were ineligible. Ethnicity and specialty of physician, practice type, data management availability, and patient age were significantly associated with trial availability. Patients with >4 comorbidities (OR 4.5; CI 1.7-11.8) had higher odds of trial ineligibility. Non-White patients (OR 7.9; CI 1.3-46.2) and patients of Black physicians had greater odds of enrolling (OR 56.5; CI 1.1-999.9) in a therapeutic trial. Significant patient therapeutic trial enrollment factors: belief trial may help (OR 76.9; CI 4.9->1000), concern about care if not on trial (OR12.1; CI 2.1-71.4), pressure to enroll (OR .27; CI 0.12-.64), caregiving without pay (OR 0.13; CI .02-.84). Significant physician beliefs were: patients would not do well on standard therapy (OR 3.6; CI 1.6-8.4), and trial would not be time consuming (OR 3.3; CI 1.3-8.1).

CONCLUSIONS

Trial availability, patient and physician beliefs were factors identified that if modified could improve enrollment in cancer cooperative group clinical trials.

Balkan (endemic) nephropathy

The clinical and pathological features of Balkan (endemic) nephropathy are discussed and correlations of incidence with excess late summer and autumn rainfall outlined. Cultures of a strain of Penicillium verrucosum var. cyclopium isolated from maize collected in an endemic area were fed to rats and lesions were produced in the straight third segment of the proximal kidney tubules. Extensive degeneration and nuclear changes were seen and on prolonged feeding further nuclear enlargement (to greater than 6n) and the formation of multinucleate cells occurred. The relevance of these findings to the clinical disease in man, especially the occurrence of urinary tract tumours, and the evidence supporting mycotoxin involvement, are discussed.

Multiple indicators, multiple causes measurement error models

Multiple indicators, multiple causes (MIMIC) models are often employed by researchers studying the effects of an unobservable latent variable on a set of outcomes, when causes of the latent variable are observed. There are times, however, when the causes of the latent variable are not observed because measurements of the causal variable are contaminated by measurement error. The objectives of this paper are as follows: (i) to develop a novel model by extending the classical linear MIMIC model to allow both Berkson and classical measurement errors, defining the MIMIC measurement error (MIMIC ME) model; (ii) to develop likelihood-based estimation methods for the MIMIC ME model; and (iii) to apply the newly defined MIMIC ME model to atomic bomb survivor data to study the impact of dyslipidemia and radiation dose on the physical manifestations of dyslipidemia. As a by-product of our work, we also obtain a data-driven estimate of the variance of the classical measurement error associated with an estimate of the amount of radiation dose received by atomic bomb survivors at the time of their exposure.

Renal function, calcium regulation, and time to hospitalization of patients with chronic kidney disease

BACKGROUND

Chronic kidney disease is associated with disruption of the endocrine system that distorts the balance between calcitriol, calcium, phosphate and parathyroid hormone in the calcium regulation system. This can lead to calcification of the arterial tree and increased risk of cardiovascular disease and death. In this study we develop a health metric, based on biomarkers involved in the calcium regulation system, for use in identifying patients at high risk for future high-cost complications.

METHODS

This study is a retrospective observational study involving a secondary analysis of data from the kidney disease registry of a regional managed care organization. Chronic kidney disease patients in the registry from November 2007 through November 2011 with a complete set of observations of estimated glomerular filtration rate, calcitriol, albumin, free calcium, phosphate, and parathyroid hormone were included in the study (n = 284). Weibull regression model was used to identify the most significant lab tests in predicting "waiting time to hospitalization". A multivariate linear path model was then constructed to investigate direct and indirect effects of the biomarkers on this outcome.

RESULTS

The results showed negative significant direct effects of phosphate and parathyroid hormone on "waiting time to hospitalization". Base on this result, the risk of hospitalization increases 16.8% for each 0.55 mg/dl increase in phosphate level and 13.5% for each 0.467 increase in the natural logarithm of parathyroid hormone. Positive indirect effects of calcitriol surrogate (calcidiol), free calcium, albumin and estimated glomerular filtration rate were observed but were relatively small in magnitude.

CONCLUSION

Variables involved in the calcium regulation system should be included in future efforts to develop a quality of care index for Chronic Kidney disease patients.

Lifetime risk estimators in epidemiological studies of Krabbe Disease: Review and Monte Carlo comparison

This review addresses difficulties arising in estimating epidemiological parameters of leukodystrophies and lysosomal storage disorders, with special focus on Krabbe disease. Although multiple epidemiological studies of Krabbe disease have been published, these studies are difficult to reconcile since they have used different study populations and varying methods of calculation. Confusion exists regarding which epidemiological parameters have been estimated; the current review shows that most previous estimates can be properly interpreted as lifetime risk at birth. One of the most common estimation methods is shown to be inaccurate, while two other methods are shown to be approximately accurate. Based on the results of the current paper, recommendations are made that are expected to improve the quality of future studies of Krabbe disease. It is anticipated that these recommendations will be applicable to epidemiological studies of other lysosomal storage disorders, as well as any other rare diseases diagnosed with enzymatic screening.

Predicting hospital cost in CKD patients through blood chemistry values

Background

Controversy exists in predicting costly hospitalization in patients with chronic kidney disease and co-morbid conditions. We therefore tested associations between serum chemistry values and the occurrence of in-patient hospital costs over a thirteen month study period. Secondarily, we derived a linear combination of variables to estimate probability of such occurrences in any patient.

Method

We calculated parsimonious values for select variables associated with in-patient hospitalization and compared sensitivity and specificity of these models to ordinal staging of renal disease.

Data from 1104 de-identified patients which included 18 blood chemistry observations along with complete claims data for all medical expenses.

We employed multivariable logistic regression for serum chemistry values significantly associated with in-patient hospital costs exceeding $3,000 in any single month and contrasted those results to other models by ROC area curves.

Results

The linear combination of weighted Z scores for parathyroid hormone, phosphorus, and albumin correlated with in-patient hospital care at p < 0.005. ROC curves derived from weighted variables of age, eGFR, hemoglobin, albumin, creatinine, and alanine aminotransferase demonstrated significance over models based on non-weighted Z scores for those same variables or CKD stage alone. In contrast, the linear combination of weighted PTH, PO4 and albumin demonstrated better prediction, but not significance over non-weighted Z scores for PTH alone.

Conclusion

Further study is justified to explore indices that predict costly hospitalization. Such metrics could assist Accountable Care Organizations in evaluating risk adjusted compensation for providers.

Relating illness complexity to reimbursement in CKD patients

Background:

Despite significant investments of federal and state dollars to transition patient medical records to an all-electronic system, a chasm still exists between health care quality and payment for it. A major reason for this gap is the difficulty in evaluating health care outcomes based on claims data. Since both payers and patients may not appreciate how illness complexity impacts treatment outcomes, it is difficult to determine fair provider compensation.

Objectives:

Chronic kidney disease (CKD) typifies these problems and is often associated with comorbidities that impact cost, health, and work productivity. Thus, the objective of this study was to evaluate an illness complexity score (ICS) based on a linear regression of select blood values that might assist in predicting average monthly reimbursements in CKD patients. A second objective was to compare the results of this ICS prediction to results obtained by prediction of average monthly reimbursement using CKD stage. A third objective was to analyze the relationship between the change in ICS, estimated glomerular filtration rate (eGFR), and CKD stage over time to average monthly reimbursement.

Methods:

We calculated parsimonious values for select variables associated with CKD patients and compared the ICS to ordinal staging of renal disease. Data from 177 de-identified patients over 13 months was collected, which included 15 blood chemistry observations along with complete claims data for all medical expenses. To test for the relationship between average blood chemistry values, stages of CKD, age, and average monthly reimbursement, we modeled an association through a linear regression function of age, eGFR, and the Z-scores calculated from average monthly values of phosphorus, parathyroid hormone, glucose, hemoglobin, bicarbonate, albumin, creatinine, blood urea nitrogen, potassium, calcium, sodium, alkaline phosphatase, alanine aminotransferase, and white blood cells.

Results:

The results of our study demonstrated that the association between average ICS values throughout the entire study period predicted average monthly reimbursements with an R² value of 0.41. Comparing that value to the association between the average CKD stage and average monthly reimbursement demonstrated an R² value of 0.08. Thus, ICS offers five times greater sensitivity over CKD staging as a measure of illness complexity.

Conclusion:

Sorting the patient population by changes in CKD stage or ICS over the entire study period revealed significant differences between the two scoring methods. Groups scored by ICS demonstrated greater sensitivity by capturing dysfunction in other organ systems and had a better association with reimbursement than groups scored by CKD staging.

Early infantile Krabbe disease: results of the World-Wide Krabbe Registry

New York State began screening for Krabbe disease in 2006 to identify infants with Krabbe disease before symptom onset. Because neither galactocerebrosidase activity nor most genotypes reliably predict phenotype, the World Wide Registry was developed to determine whether other clinical/neurodiagnostic data could predict early infantile Krabbe disease in the newborn screening population. Data on disease course, galactocerebrosidase activity, DNA mutations, and initial neurodiagnostic studies in 67 symptomatic children with early infantile Krabbe disease were obtained from parent questionnaires and medical records. Initial signs included crying/irritability, cortical fisting, and poor head control. Galactocerebrosidase activity was uniformly low. Eight of 17 manifested novel mutations. Ninety-two percent (n = 25) exhibited elevated cerebrospinal fluid protein; 76% (n = 42) demonstrated abnormal magnetic resonance images; 67% (n = 15) exhibited abnormal computed tomography findings; 43% (n = 28) produced abnormal electroencephalogram findings; 100% (n = 5) demonstrated abnormal nerve conduction velocities; 83% (n = 6) produced abnormal brainstem evoked responses; and 50% (n = 6) exhibited abnormal visual evoked responses. One, 2, and 3 year survivals were 60%, 26%, and 14%, respectively. Although most symptomatic patients with the early infantile phenotype manifested abnormal cerebrospinal fluid protein, magnetic resonance imaging, brainstem evoked responses, and nerve conduction velocities, studies of affected children may be normal. Other biomarkers are needed to predict phenotype in the newborn screening population.

Mortality rates due to gynecologic cancers in New York state by demographic factors and proximity to a Gynecologic Oncology Group member treatment center: 1979-2001

OBJECTIVE

To describe trends in mortality rates, in New York State, due to cervical, endometrial and ovarian cancer and to assess how these rates varied with proximity to a comprehensive cancer treatment center or population density (rural/urban).

METHODS

Data were obtained from the Centers for Disease Control and Prevention (CDC)'s Compressed Mortality Files, Census Bureau records, and online maps. Poisson regression models were fitted to estimate death rates (mean number of deaths per 100,000 women per year) due to gynecologic cancer type. Trends in death rates were compared with respect to driving time to the nearest comprehensive cancer treatment center and population density, controlling for race, county income level, and age at death.

RESULTS

Cervical and endometrial but not ovarian death rates declined over time. For both cervical and endometrial cancers, death rates varied significantly with driving time and between rural and urban counties. In the case of cervical cancer, the decline over time was steeper in rural than in urban counties. For endometrial cancer, the decline steepened with increasing distance from a treatment center.

CONCLUSION

Improvements in cervical and endometrial cancer mortality from 1979 to 2001 followed increases in gynecologic cancer treatment research efforts, number of specialists trained to treat such cases, and in the emphasis on gynecologic cancer in the training of physicians in general. Our results are consistent with an interpretation that the progressive actions by leaders in the gynecologic oncology profession during the late 1960's and early 1970's contributed to improvements in mortality rates in subsequent decades.

Standardized risk and description of results from multivariable modeling of a binary response

Descriptions of significant associations found from a logistic regression analysis typically are based on adjusted odds ratios. Unfortunately, odds ratios provide no information about the prevalence of response. In this paper, we justify and recommend using standardized risks, i.e., standardized probabilities, which do provide information about prevalence, in addition to adjusted odds ratios, for pairwise comparisons of the levels of a significant factor. We illustrate the advantages of generally reporting standardized risk estimates, in the context of assessing the effect of blood lead levels during the preschool years on occurrence of academic problems in kindergarten. Results are more meaningfully interpreted when accompanied by standardized risk estimates.

Risk factors for infant maltreatment: a population-based study

CONTEXT

Of the approximately 900,000 children who were determined to be victims of abuse or neglect by US child protective services in 2002, the birth-to-3 age group had the highest rate of victimization (1.6%) and children younger than 1 accounted for the largest percentage of victims (9.6%).

OBJECTIVE

To identify perinatal and sociodemographic risk factors associated with maltreatment of infants up to 1 year of age.

DESIGN AND SETTING

Observational cohort study.

PARTICIPANTS

189,055 children born in 1996 in Florida.

MAIN OUTCOME MEASURE

Infant maltreatment, defined as a verified report of abuse, neglect, or threatened harm that occurred between day 3 of life and 1 year.

RESULTS

1,602 children (.85%) of the 1996 birth cohort had verified instances of maltreatment by age 1. Of 15 perinatal and sociodemographic variables studied, 11 were found to be significantly related to infant maltreatment. Five factors had adjusted relative risks (RR) of two or greater: Mother smoked during pregnancy (RR 2.8); more than two siblings (RR 2.7); Medicaid beneficiary (RR 2.1); unmarried marital status (RR 2.0); low birth weight infant (RR 2.0). Infants who had four of these five risk factors had a maltreatment rate seven times higher than the population average.

CONCLUSIONS

Data on nearly all risk factors found to be significantly associated with infant maltreatment are available on the birth certificate. Such information can be incorporated into a population-based risk-assessment tool that could identify subpopulations at highest risk for infant maltreatment. Because resources are limited, these groups should be given priority for enrollment in child abuse prevention programs.

Patency of autogenous and polytetrafluoroethylene upper extremity arteriovenous hemodialysis accesses: a systematic review

OBJECTIVE

Patency rates for autogenous accesses are presumed to be better than for polytetrafluoroethylene (PTFE) accesses, although the strength of the supporting evidence is limited. We undertook this study to test the hypothesis that patency rates for upper extremity autogenous hemodialysis arteriovenous accesses in adults are superior to those for PTFE counterparts.

METHODS

A systematic review of relevant literature and meta-analysis of the patency data were performed. Studies were considered acceptable if patency data were reported by either life table or Kaplan-Meier method, including number of patients at risk.

RESULTS

The thirty-four studies that satisfied the inclusion criteria were composed predominantly of case series or nonrandomized controlled studies; no randomized, controlled studies comparing autogenous and PTFE accesses were included. The primary patency rate for autogenous accesses was 72% (95% confidence interval [CI], 70%-74%) at 6 months and 51% (95% CI, 48%-53%) at 18 months, and the corresponding primary patency rate for PTFE accesses was 58% (95% CI, 56%-61%) and 33% (95% CI, 31%-36%), respectively. The secondary patency rate for autogenous accesses was 86% (95% CI, 84%-88%) at 6 months and 77% (95% CI, 74%-79%) at 18 months, and the corresponding secondary patency rate for PTFE accesses was 76% (95% CI, 73%-79%) and 55% (95% CI, 51%-59%), respectively.

CONCLUSIONS

The patency rate for autogenous upper extremity arteriovenous hemodialysis accesses in adults is superior to that for PTFE counterparts, although the overall quality of the studies in the meta-analysis was less than ideal. Randomized, controlled studies to further examine the differences in outcome between these two access types are necessary.

A population-based study of the effects of birth weight on early developmental delay or disability in children

Improving medical treatment of extremely low-birth-weight infants over the last 20 to 30 years resulted in increased survival rates. The developmental sequela of salvaged infants is of great interest to perinatologists. The primary purposes of the current study were to assess the effect of birth weight (BW) on developmental delay or disability (DDD) in the first three years of life and determine whether there is a BW threshold below which all infants should be evaluated to determine if intervention services for children with DDD should be received. Three statewide databases were merged: 1998 Birth Vital Statistics; 1997-1998 Medicaid eligibility files; and 1998-2001 Children's Medical Services' Early Intervention Program (CMS-EIP) data. Infants who died within the first year of life and plural births were excluded. The final dataset consisted of 170,874 records. A child was determined to have a DDD if a developmental delay, or an established condition, such as sensory impairment, genetic, metabolic, neurological, or severe attachment disorders, was diagnosed through a multidisciplinary evaluation. Logistic regression models were used to relate BW to DDD, controlling for sociodemographic, behavioral, and perinatal variables. Adjusted odds ratios (OR) were calculated to describe the effects of BW on DDD. There was a significant effect of BW on DDD (Adjusted OR &equals 97.50, 40.01, 15.84, 3.29, 1.39, 1.00, 1.52 for BW categories 450-749, 750-999, 1000-1499, 1500- 2499, 2500-2999, 3000-4749, 4750-6050 g, respectively). In these categories, 70%, 56%, 36%, 11%, 4%, 3%, and 6% of surviving singleton infants, respectively, suffered a DDD in their first 3 years of life. Four medical, five sociodemographic, and two behavioral factors were significant in addition to BW. An equation for predicting the probability of DDD given these factors was obtained, and its use exemplified. BW is strongly associated with DDD. Over 60% of infants weighing < 1000 g and nearly half (46%) of those weighing < 1500 g at birth are diagnosed with a DDD before 3 years of age. The probability of DDD for a specific infant also varies by sociodemographic, other perinatal, and behavioral factors. The results of this paper suggest that all surviving infants of BW < 1000 g, and perhaps < 1500 g, should be automatically referred for evaluation.

A risk assessment screening test for very low birth weight

OBJECTIVES

To develop a risk-assessment screening tool for very low birth weight (VLBW) and to compare our empirically derived tool to the nonempirically derived screening tool used by the State of Florida.

METHODS

Birth records from the State of Florida Vital Statistics between 04/01/92 and 12/07/94 were matched with State Healthy Start prenatal records, reported from 04/01/92 through 03/31/94. Known and additional potentially important risk factors were identified from both sources. Generalized Linear Modeling techniques were used to estimate associations between risk factors and VLBW. A risk assessment system was then developed using the estimated model. The resulting screening test was compared with the one used by the Florida State Department of Health in terms of sensitivity and specificity on an independent validation sample.

RESULTS

The proposed screening tool had comparable specificity to the Healthy Start screening tool but significantly better sensitivity. Both instruments are simple and easy to implement.

CONCLUSIONS

Identification of women at high risk for VLBW would be improved using the model-based screening tool developed in this paper. Public health policy makers should use statistical methods in addition to expert opinion to improve existing risk assessment methods. The actual value of an improved screening instrument is dependent on the availability of effective intervention programs.

Effect of teenage pregnancy on educational disabilities in kindergarten

Teenage pregnancies have become a public health issue because of their observed negative effects on perinatal outcomes and long-term morbidity. The association of young maternal age and long-term morbidity is usually confounded, however, by the high prevalence of poverty, low level of education, and single marital status among teenage mothers. The authors assess the independent effect of teenage pregnancy on educational disabilities and educational problems in a total population of children who entered kindergarten in Florida in 1992--1994 and investigate how controlling for potentially confounding factors affects the relation between teenage pregnancies and poor outcome. When no other factors are taken into account, children of teenage mothers have significantly higher odds of placement in certain special education classes and significantly higher occurrence of milder education problems, but when maternal education, marital status, poverty level, and race are controlled, the detrimental effects disappear and even some protective effects are observed. Hence, the increased risk for educational problems and disabilities among children of teenage mothers is attributed not to the effect of young age but to the confounding influences of associated sociodemographic factors. In contrast to teen age, older maternal age has an adverse effect on a child's educational outcome regardless of whether other factors are controlled for or not.

The outcome in the United States after thoracoabdominal aortic aneurysm repair, renal artery bypass, and mesenteric revascularization

OBJECTIVES

The purpose of this study was to determine outcome and identify predictors of death after thoracoabdominal aortic aneurysm (TAA) repair, renal artery bypass (RAB), and revascularization for chronic mesenteric ischemia (CMI).

PATIENTS AND METHODS

In this retrospective analysis, data were obtained from the Nationwide Inpatient Sample, a 20% all-payer stratified sample of hospitals in the United States during 1993 to 1997. Patients were identified by the presence of a diagnostic or procedure code from the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). The main outcomes we examined were death, ICD-9-CM -based complications, length of stay, hospital charges, and disposition. A multivariate model was constructed to predict death.

RESULTS

A total of 2934 patients were identified (TAA, 540; RAB, 2058; CMI, 336) in the database. The mean age was comparable (TAA, 69 +/- 9 years; RAB, 66 +/- 12 years; CMI, 66 +/- 11 years), but the breakdown between the sexes varied by procedure (male: TAA, 53%; RAB, 55%; CMI, 24%). The mortality rate (TAA, 20.3%; RAB, 7.1%; CMI, 14.7%), complication rate (TAA, 62.2%; RAB, 37.4%; CMI, 44.6%), and the percentage of patients discharged to another institution (TAA, 21.2%; RAB, 9.3%; CMI, 12.0%) were clinically significant for all procedures. The mortality rate for RAB was greater when performed concomitant with an aortic reconstruction (4.4% vs 8.3%). All three procedures were resource intensive as reflected by the median length of stay (TAA, 14 days; RAB, 9 days; CMI, 14 days) and median hospital charges (TAA, $64,493; RAB, $36,830; CMI, $47,390). The multivariate model identified several variables for each procedure that had an impact on the predicted mortality rate (TAA, 14%-76%; RAB, < 1%-46%; CMI, < 2%-87%).

CONCLUSIONS

The operative mortality rates across the United States for patients undergoing TAA repair and RAB are greater than commonly reported in the literature and mandate reexamining the treatment strategies for these complex vascular problems.

Extragenic suppressors of the nimX2(cdc2) mutation of Aspergillus nidulans affect nuclear division, septation and conidiation

The Aspergillus nidulans NIMX(CDC2) protein kinase has been shown to be required for both the G(2)/M and G(1)/S transitions, and recent evidence has implicated a role for NIMX(CDC2) in septation and conidiation. While much is understood of its G(2)/M function, little is known about the functions of NIMX(CDC2) during G(1)/S, septation, and conidiophore development. In an attempt to better understand how NIMX(CDC2) is involved in these processes, we have isolated four extragenic suppressors of the A. nidulans nimX2(cdc2) temperature-sensitive mutation. Mutation of these suppressor genes, designated snxA-snxD for suppressor of nimX, affects nuclear division, septation, and conidiation. The cold-sensitive snxA1 mutation leads to arrest of nuclear division during G(1) or early S. snxB1 causes hyperseptation in the hyphae and sensitivity to hydroxyurea, while snxC1 causes septation in the conidiophore stalk and aberrant conidiophore structure. snxD1 leads to slight septation defects and hydroxyurea sensitivity. The additional phenotypes that result from the suppressor mutations provide genetic evidence that NIMX(CDC2) affects septation and conidiation in addition to nuclear division, and cloning and biochemical analysis of these will allow a better understanding of the role of NIMX(CDC2) in these processes.

Raman spectra of the double-anion salts M3ZnCl4NO3 (M+ = K+, Rb+, NH4)

Recently characterized K3ZnCl4NO3 and (NH4)3ZnCl4NO3, and newly prepared Rb3ZnCl4NO3 constitute a limited series of isomorphous double-anion salts (space group Pnma, Z = 4). Room-temperature (295 K) Raman spectra from polycrystalline samples of the compounds are reported and interpreted on the basis of the Cs site symmetry of the ZnCl4(2-) and NO3- ions with reference to the D2h factor group of the unit cell. The spectra are compared with Raman spectra of the corresponding M2ZnCl4 and MNO3 single-anion salts. Relative positions and frequencies of the ZnCl4(2-) modes vary considerably among the M3ZnCl4NO3 compounds, despite the isomorphism. The NO3- modes are more similar in all three compounds. The NO3- doubly degenerate v3 and V4 modes are split into two distinct bands as a result of the decent in symmetry from D3h for the free ion to Cs at the crystallographic site. The unequal intensities of the v3 bands observed for K3ZnCl4NO3 and Rb3ZnCl4NO3 and the equal intensities of the v4 bands observed for all three compounds suggest the same factor-group assignments as the high-temperature phase NH4NO3(III). The free-ion Raman-inactive planar deformation mode, v2, is evident in all three compounds, but with lesser intensity than its overtone 2v2. In K3ZnCl4NO3 and Rb3ZnCl4NO3, the symmetric stretching band, in addition to the very strong component for v1, shows a weak, low-frequency band found in many ionic nitrates, which has been attributed to thermally disordered nitrate ions or hot bands. This feature is not found in the spectrum of (NH4)3ZnCl4NO3. The 12 NH4+ ions in the unit cell of (NH4)3ZnCl4NO3, which occupy C1 and Cs sites in a 2:1 ratio, give rise to extremely broad bands that show no evidence of the individual symmetry distinctions of the cations. The broad band from NH4+ v4 obscures the region in which NO3- v3 bands are expected, but the NO3- overtone 2v2 is evident as a sharp peak above a similarly broad band from NH4+ v2.

Effect of pollution on genetic diversity in the bay mussel Mytilus galloprovincialis and the acorn barnacle Balanus glandula

To test if environmental contamination acts as a selection force affecting genetic diversity at the population level, two intertidal invertebrate species, Mytilus galloprovincialis and Balanus glandula, were collected from seven different bay sites in southern California. Collections were made at three relatively pristine 'clean' sites and four 'impacted' sites exposed to heavy industrial or boating activity, and which had previously been identified as having measurable levels of pollution. Genetic diversity at each site was assessed by comparing fragment polymorphisms generated from genomic DNA by randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). All populations retained a large amount of genetic diversity and were genetically similar to each other. However, several different measures of diversity indicated that, for most primers, the populations of both species from impacted sites had lower genetic diversity compared to those populations from clean sites. Individuals at impacted sites were more likely to share the same haplotypes than were those from clean sites. Few bands seen in the clean sites were absent from the impacted sites or vice versa, but a number of bands in the clean site populations were significantly less common in the impacted populations, while a few bands uncommon in clean site populations were more common at impacted sites. Together, these results suggest that pollution at the impacted sites may reduce genetic diversity among the resident invertebrate populations.

Improved outcome in children with advanced stage B-cell non-Hodgkin's lymphoma (B-NHL): results of the United Kingdom Children Cancer Study Group (UKCCSG) 9002 protocol

From July 1990 to March 1996, 112 children with stage III or IV B-cell non-Hodgkin's lymphoma (B-NHL) with up to 70% FAB L3-type blasts (n = 42) in the bone marrow without central nervous system (CNS) disease were treated on the United Kingdom Children Cancer Study Group (UKCCSG) 9002 protocol (identical to the French LMB 84). The median age was 8.3 years. There were 81 boys and 31 girls. According to the extent of the primary disease, patients were sub-staged into three groups: IIIA with unresectable abdominal tumour (n = 39); IIIB with abdominal multiorgan involvement (n = 57) and IIIX with extra-abdominal primary lymphoma often presenting as pleural effusion (n = 16). Univariate and multivariate analyses were carried out to evaluate the prognostic significance of lactate dehydrogenase (LDH) level at diagnosis, the sub-stage and the time to achieve complete remission (CR). With a median follow up of 48 months (range 12-92), the overall and event free survival (EFS) is 87% (95% confidence interval (CI) 79.2-92.1 %) and 83.7% (95% CI 76.3-89.2%) respectively. Six patients (5.4%) never achieved CR, of whom one is alive following high-dose therapy. Eight patients (7.1%) relapsed after achieving CR, three are alive after second-line therapy. There were three early toxic deaths (2.7%), mainly from infection, and one late death from a second cancer. There was no significant difference in EFS according to LDH level at diagnosis, the sub-stage or the time to CR. This study confirms the overall good prognosis and low rate of toxic deaths in patients with advanced B-NHL treated with this intensive regimen. No significant difference in EFS according to the sub-stage, the time to achieve CR or LDH level at diagnosis making it difficult to identify a group that should not receive intensive therapy.

The impact of low birth weight, perinatal conditions, and sociodemographic factors on educational outcome in kindergarten

OBJECTIVE

To assess the relative effects and the impact of perinatal and sociodemographic risk factors on long-term morbidity within a total birth population in Florida.

METHODS

School records for 339 171 children entering kindergarten in Florida public schools in the 1992-1993, 1993-1994, or 1994-1995 academic years were matched with Florida birth records from 1985 to 1990. Effects on long-term morbidity were assessed through a multivariate analysis of an educational outcome variable, defined as placement into 9 mutually exclusive categories in kindergarten. Of those categories, 7 were special education (SE) classifications determined by statewide standardized eligibility criteria, 1 was academic problems, and the reference category was regular classroom. Generalized logistic regression was used to simultaneously estimate the odds of placement in SE and academic problems. The impact of all risk factors was assessed via estimated attributable excess/deficit numbers, based on the multivariate analysis.

RESULTS

Educational outcome was significantly influenced by both perinatal and sociodemographic factors. Perinatal factors had greater adverse effects on the most severe SE types, with birth weight <1000 g having the greatest effect. Sociodemographic predictors had greater effects on the mild educational disabilities. Because of their greater prevalence, the impact attributable to each of the factors (poverty, male gender, low maternal education, or non-white race) was between 5 and 10 times greater than that of low birth weight and >10 times greater than that of very low birth weight, presence of a congenital anomaly, or prenatal care.

CONCLUSIONS

Results are consistent with the hypothesis that adverse perinatal conditions result in severe educational disabilities, whereas less severe outcomes are influenced by sociodemographic factors. Overall, sociodemographic factors have a greater total impact on adverse educational outcomes than perinatal factors.

Synthesis, opioid receptor binding, and biological activities of naltrexone-derived pyrido- and pyrimidomorphinans

A series of pyrido- and pyrimidomorphinans (6a-h and 7a-g) were synthesized from naltrexone and evaluated for binding and biological activity at the opioid receptors. The unsubstituted pyridine 6a displayed high affinities at opioid delta, mu, and kappa receptors with K(i) values of 0.78, 1.5, and 8.8 nM, respectively. Compound 6a was devoid of agonist activity in the mouse vas deferens (MVD) and guinea pig ileum (GPI) preparations but was found to display moderate to weak antagonist activity in the MVD and GPI with K(e) values of 37 and 164 nM, respectively. The pyrimidomorphinans in general displayed lower binding potencies and delta receptor binding selectivities than their pyridine counterparts. Incorporation of aryl groups as putative delta address mimics on the pyrido- and pyrimidomorphinan framework gave ligands with significant differences in binding affinity and intrinsic activity. Attachment of a phenyl group at the 4'-position of 6a or the equivalent 6'-position of 7a led to dramatic reduction in binding potencies at all the three opioid receptors, indicating the existence of a somewhat similar steric constraint at the ligand binding sites of delta, mu, and kappa receptors. In contrast, the introduction of a phenyl group at the 5'-position of 6a did not cause any reduction in the binding affinity at the delta receptor. In comparison to the unsubstituted pyridine 6a, the 5'-phenylpyridine 6c showed improvements in mu/delta and kappa/delta binding selectivity ratios as well as in the delta antagonist potency in the MVD. Interestingly, introduction of a chlorine atom at the para position of the pendant 5'-phenyl group of 6c not only provided further improvements in delta antagonist potency in the MVD but also shifted the intrinsic activity profile of 6c from an antagonist to that of a mu agonist in the GPI. Compound 6d thus possesses the characteristics of a nonpeptide mu agonist/delta antagonist ligand with high affinity at the delta receptor (K(i) = 2.2 nM), high antagonist potency in the MVD (K(e) = 0.66 nM), and moderate agonist potency in the GPI (IC(50) = 163 nM). Antinociceptive evaluations in mice showed that intracerebroventricular (icv) injections of 6d produced a partial agonist effect in the 55 degrees C tail-flick assay and a full agonist effect in the acetic acid writhing assay (A(50) = 7.5 nmol). No signs of overt toxicity were observed with this compound in the dose ranges tested. Moreover, repeated icv injections of an A(90) dose did not induce any significant development of antinociceptive tolerance in the acetic acid writhing assay. The potent delta antagonist component of this mixed mu agonist/delta antagonist may be responsible for the diminished propensity to produce tolerance that this compound displays.

Effect of reproductive status on feline renal size

Renal length and width dimensions were determined from survey radiography and excretory urography in 28 cats of various sex and reproductive status. Renal dimensions were expressed as a ratio to the length of the second lumbar vertebra. Renal dimensions were not significantly different when males were compared to females. However, significant differences in renal dimensions between intact and neutered cats were identified. Renal length ratios for neutered cats were: left kidney 2.22 +/- 0.14 (mean +/- standard deviation), right kidney 2.29 +/- 0.14. In intact cats, renal length ratios were: left kidney 2.60 +/- 0.19, right kidney 2.65 +/- 0.24. The mean renal length ratios for neutered cats was smaller than previously reported normal values. Thus, reproductive status should be considered when evaluating feline kidneys for alterations in size. Based on this study, normal feline renal length ratios range from 1.9 to 2.6 for neutered cats and 2.1 to 3.2 for intact cats.

An assessment of the operation of an external quality assessment (EQA) scheme in histopathology in the South Thames (West) region: 1995-1998

AIMS

To describe the design and organisation of a voluntary regional external quality assessment (EQA) scheme in histopathology, and to record the results obtained over a three year period.

METHODS

A protocol is presented in which circulation of EQA slides alternated with teaching sessions. Procedures for the choice of suitable cases, evaluation of submitted diagnoses, and feedback of results to participants are described. The use of teaching sessions, complementary to the slide circulations, and dealing with current diagnostic problems is also outlined.

RESULTS

Participation rates in the nine slide circulations varied between 66% and 89%, mean 85%. Overall scores were predictably high but 4% of returns, from 10 pathologists, were unsatisfactory. These low scores were typically isolated or intermittent and none of the participants fulfilled agreed criteria for chronic poor performers.

CONCLUSIONS

This scheme has been well supported and overall performances have been satisfactory. The design was sufficiently discriminatory to reveal a few low scores which are analysed in detail. Prompt feedback of results to participants with identification of all "incomplete" and "wrong" diagnoses is essential. Involvement of local histopathologists in designing, running, and monitoring such schemes is important.

Conservative management of follicular non-Hodgkin's lymphoma in childhood

Among 447 children with non-Hodgkin's lymphoma (NHL) on the childhood U.K. registry, seven children with follicular (NHL) were identified. Four were male and their age ranged from 4.25 to 13.5 years (median 7.5); all had localized disease, Murphy's stage I (n = 4) and II (n = 3). Sites involved at presentation were cervical lymph nodes and tonsils (n = 5), ileum (n = 1) and parotid gland (n = 1). Three had complete surgical excision only and four had complete (n = 1) or incomplete excision (n= 3) followed by a short multi-agent chemotherapy regimen (UKCCSG 9001 protocol). With a median follow-up of 1.5 years (range 0.25-5 years) from diagnosis, six are alive in complete remission (CR) including three who had no chemotherapy. These results confirm previous reports that follicular lymphomas in children are rare (1.5%) and tend to be localized at presentation. Their rarity makes it difficult to produce guidelines about treatment, but in localized cases a period of non-intervention may be justified.

Educational disabilities of neonatal intensive care graduates

OBJECTIVE

To determine the relationship between perinatal and sociodemographic factors in low birth weight and sick infants hospitalized at regional neonatal intensive care units (NICUs) and subsequent educational disabilities.

METHOD

NICU graduates born between 1980 and 1987 at nine statewide regionalized level III centers were located in Florida elementary schools (kindergarten through third grade) during academic year 1992-1993 (n = 9943). Educational disability was operationalized as placement into eight mutually exclusive types of special education (SE) classifications determined by statewide standardized eligibility criteria: physically impaired, sensory impaired (SI), profoundly mentally handicapped, trainable mentally handicapped, educable mentally handicapped, specific learning disabilities, emotionally handicapped, and speech and language impaired (SLI). Logistic regression was used to estimate the odds of placement in SE for selected perinatal and sociodemographic variables.

RESULTS

Placement into SE ranged from .8% for SI to 9.9% for SLI. Placement was related to four perinatal factors (birth weight, transport, medical conditions [congenital anomalies, seizures or intraventricular hemorrhage] and ventilation), and five sociodemographic factors (child's sex, mother's marital status, mother's race, mother's educational level, and family income). Perinatal factors primarily were associated with placement in physically impaired, SI, profoundly mentally handicapped, and trainable mentally handicapped. Perinatal and sociodemographic factors both were associated with placement in educable mentally handicapped and specific learning disabilities whereas sociodemographic factors primarily were associated with placement in emotionally handicapped and SLI.

CONCLUSIONS

Educational disabilities of NICU graduates are influenced differently by perinatal and sociodemographic variables. Researchers must take into account both sets of these variables to ascertain the long-term risk of educational disability for NICU graduates. Birth weight alone should not be used to assess NICU morbidity outcomes.

Synthesis, opioid receptor binding, and bioassay of naltrindole analogues substituted in the indolic benzene moiety

A series of analogues of the delta opioid receptor antagonist naltrindole (1) possessing a phenyl, phenoxy, or benzyloxy group at the 4'-, 5'-, 6'-, or - 7'-positions (4-15) and a 2-(2-pyridinyl)ethenyl group at the 5'-position (16) on the indolic benzene ring were synthesized through Fischer indolization of naltrexone. Compounds 4-16 were evaluated for their affinities in opioid receptor binding assays in rat or guinea pig brain membranes and for their opioid antagonist and agonist activities in vitro on the guinea pig ileum (GPI) and mouse vas deferens (MVD) preparations. All of the compounds displayed delta selectivity in binding to the delta, mu, and kappa opioid receptors. The binding potencies of most of the compounds at the delta, mu, and kappa sites, however, were lower than that of 1. Among positional isomers, the 7'-substituted compounds in general had higher affinities than 6'-, 5'-, or 4'-substituted analogues, indicating that bulky groups are tolerated better at the 7'-position than at other positions. The affinity of the compounds were also determined at putative subtypes of the delta and kappa receptors: deltacx-1 (mu-like), deltacx-2 (delta-like), and the kappa2b site in an attempt to identify subtype selective agents. Although none were identified, the data revealed a different rank-order of potency beteween mu vs deltacx-1, deltacx-2 vs delta, and the kappa2b vs mu, delta, and kappa1. The antagonist potencies of the compounds in the MVD were in agreement with their binding affinities at the delta site in rat brain membrane. The most potent member of the series, the 7'-phenoxy compound 14, binds to the delta site with a Ki of 0.71 nM, shows >40-fold delta over mu and delta over kappa binding selectivity, and exhibits delta receptor antagonist potency in the MVD with a Ke of 0.25 nM, properties which are comparable to the delta receptor affinity and antagonist potency of naltrindole (Ki = 0.29 nM, Ke = 0. 49 nM). Interestingly, many members of the series were found to possess significant partial to full agonist activities in the MVD (6, 9, 10, 13, 16) or GPI (6, 11, 14, 15). Among the compounds studied, the highest agonist activity in the MVD was displayed by 16 (IC50 = 220 nM), and the highest agonist activity in the GPI was displayed by 14 (IC50 = 450 nM). The overall affinity and activity profile of compound 14 is, therefore, that of a nonpeptide ligand possessing mixed mu agonist/delta antagonist properties. Recently there has been considerable interest in such compounds possessing mu agonist/delta antagonist activities because of their potential therapeutic usefulness as analgesics with low propensity to produce tolerance and dependence side effects. The results of the present study suggest that morphinan derivatives related to 16 and 14 may provide useful leads for the development of potent nonpeptide ligands possessing delta agonist or mixed delta antagonist/mu agonist activities.

Loss of heterozygosity at 5q21 in non-small cell lung cancer: a frequent event but without evidence of apc mutation

Four genetic polymorphisms in the APC and MCC genes at chromosome 5q21 were analysed for loss of heterozygosity (LOH) in 97 primary squamous carcinomas and adenocarcinomas of the lung. LOH was identified in at least two polymorphic loci in 41 percent of informative cases. There was no significant difference in the frequency of LOH between squamous carcinomas and adenocarcinomas. Within the adenocarcinoma group, however, LOH appeared to be more common in tumours having a bronchial origin (5/9; 56 per cent) than in parenchymal adenocarcinoma (6/21; 29 per cent). All 32 tumours showing LOH at one or more polymorphic sites were examined for mutations in the mutation cluster region (MCR) of APC by single-strand conformational polymorphism (SSCP) analysis. Mutations were not detected in any of these cases. We therefore propose that it is likely that a tumour suppressor gene on 5q other than APC is involved in the pathogenesis of lung cancer.

Correlation between systolic blood pressure and physical development in adolescence

Although the close relation between blood pressure and physical development in adolescence has been established in cross-sectional and comparative cross-sectional studies, the entire trend of systolic blood pressure (SBP) during adolescence has not been elucidated in conjunction with physical development in a longitudinal study. Blood pressure (mmHg), body weight (kg), and body height (m) were measured annually for 418 subjects in Hiroshima and Nagasaki, Japan, from age 10 (1955 or 1956) through 18 years (1963 or 1964). The Gompertz growth model was used to determine the velocity of weight increase (VEL) during that age period. The relations between SBP from age 10 to 18 and VEL, weight, height, body mass index (BMI; weight/height2, kg/m2), and the age at which the measurements were made were investigated individually using random-coefficient growth-curve analysis. The SBP trend for the 10- to 18-year age period could be shown by the following prediction equations: for the 163 Hiroshima males, SBP = 82.38 + 0.89 VEL at age 1.15 years prior to the current examination (VEL (age - 1.15)) + 1.40 BMI; for the 57 Nagasaki males, SBP = 92.70 + 1.07 VEL (age - 1.15) + 0.79 BMI; for the 148 Hiroshima females, SBP = 104.88 + 1.63 VEL (age - 1.15) + 0.05 BMI; for the 50 Nagasaki females, SBP = 113.62 + 1.67 VEL (age - 1.15) - 0.59 BMI. VEL 1.15 years prior to the current examination was significantly and positively related to SBP in each city by sex group (p < 0.01), and current BMI was significantly related to SBP for males in Hiroshima (p < 0.01) and nearly so in Nagasaki (p = 0.06), but not for females in either city (p = 0.84 and 0.13, respectively). Because the plot of VEL was a convex curve, SBP peaked approximately 1-2 years after the peak in VEL and then decreased in both sexes. The entire SBP trend during adolescence can be expressed as an equation of VEL and BMI in males and of VEL in females. SBP does not increase linearly with age.

Lipophilic antifolates as agents against opportunistic infections. 1. Agents superior to trimetrexate and piritrexim against Toxoplasma gondii and Pneumocystis carinii in in vitro evaluations

2,4-Diaminopteridines (21 compounds) and 2,4-diamino-5-methyl-5-deazapteridines (34 compounds) along with three 2,4-diamino-5-unsubstituted-5-deazapteridines and four 2,4-diaminoquinazolines, each with an aryl groups attached to the 6-position of the heterocyclic moiety through a two-atom bridge (either CH2NH, CH2N(CH3),CH2S, or CH2CH2), were synthesized and evaluated as inhibitors of the growth of Toxoplasma gondii in culture and as inhibitors of dihydrofolate reductase enzymes from T. gondii, Pneumocystis carinii, and rat liver. Exceptionally high levels of combined potency and selectivity as growth inhibitors of T. gondii and as inhibitors of the microbial enzymes relative to the mammalian enzyme were found among the 5-methyl-5-deazapteridines but not for the other heterocyclic types. Thirty of the 34 5-methyl-5-deaza compounds gave growth inhibition IC50 values lower than that of pyrimethamine (0.4 microM) with 14 compounds below 0.1 microM, values that compare favorably with those for piritrexim and trimetrexate (both near 0.02 microM). As inhibitors of T gondii DHFR, all but three of the 34 5-methyl-5-deaza compounds gave IC50 values in the order of magnitude with those of piritrexim (0.017 microM) and trimetrexate (0.010 microM), and 17 compounds of this group gave IC50 values versus P. carinii DHFR similarly comparable with those of piritrexim (0.031 microM) and trimetrexate (0.042 microM). Thirteen of these congeners gave both T. gondii growth inhibition and DHFR inhibition IC50 values of 0.10 microM or less, thus indicating facile penetration of the cell membrane. Eleven of these inhibitors of both T. gondii growth and DHFR have selectivity ratios (IC50 rat liver divided by IC50 T. gondii) of 5 or greater for the parasite DHFR. The highest selectivity ratio of nearly 100 belongs to the 5-methyl-5-deaza compound whose 6-substituent is CH2CH2C6H3(OCH3)2-2,5. This compound is over 10(3)-fold more selective for T. gondii DHFR than bridge homologue piritrexim (selectivity ratio 0.088), a compound now in clinical trials. The candidate with CH2NHC6H3(CH3)2-2,5 in the 6-position gave the highest P. carinii DHFR selectivity ratio of 4.0, which is about 60-fold more selective than trimetrexate (0.071) and 80-fold more selective than piritrexim (0.048) toward this enzyme. The 10 best compounds with respect to potency and selectivity includes six compounds bearing 2,5-disubstituted phenyl groups in the side chain (with little, if any, difference in effects of methyl, methoxy, or ethoxy), two side chains bearing 1-naphthyl groups, and two with 5,6,7,8-tetrahydro-1-naphthyl groups. Bridge groups represented in the 10 choice compounds are CH2NH, CH2N(CH3), CH2CH2, and CH2S. The high levels of both potency and selectivity among these agents suggest that in vivo studies now underway may lead to agents that could replace trimetrexate and piritrexim in treatment of toxoplasmosis and P. carinii pneumonia.

Changes in survival patterns of very low-birth-weight infants from 1980 to 1993

OBJECTIVE

To determine changes in survival patterns among very low-birth-weight ( < 1500 g) infants between 1980 and 1993.

METHODS

The records of 12,960 infants treated in nine perinatal intensive care centers in Florida were analyzed on the basis of survival (discharged alive from hospital) according to four independent variables: birth weight, race, sex, and transport status. Survival curves were generated using log linear regression techniques for each race by sex by transport status group.

RESULTS

Race, sex, and transport status correlated significantly with survival: survival percentages were higher among black infants, female infants, and infants transported to the perinatal intensive care centers than among white infants, male infants, and those admitted initially to the tertiary care centers. After 1985, 95% of neonates with birth weights between 1200 and 1500 g survived. In addition, survival of 500- to 500-g transported black male infants increased from zero to near 80% during the 13-year period; that of 500- to 550-g inborn white female infants rose from 35% to 70%.

CONCLUSIONS

These results illustrate the value of taking into account race, sex, and transport status in efforts to understand the contribution that neonatal intensive care of extremely low-birth-weight infants makes to the lowering of infant mortality, and of using multivariable statistical procedures to generate predicted survival probabilities for different subpopulations. These probabilities can be applied to (1) predicting survival for specific subgroups of extremely low-birth-weight infants, and (2) helping physicians develop clinical guidelines for extending care to infants at the threshold of viability.

An index for early assessment of neonatal survival in low birthweight infants

Since its development in the 1950s, the Apgar index has come into widespread use as a tool to evaluate neonatal condition, with predictive implications for mortality and morbidity. However, Apgar scores were validated in predominantly term infants and have questionable prognostic value for low birthweight infants. The purpose of this study was to develop a survival index applicable to premature infants. Thirty-six perinatal variables were evaluated initially, based on data from 441 neonates weighing 500 to 1800 g. A multifactorial index of nine variables was derived, each independently related to mortality. Sensitivity of the index was 95%, specificity was 68%, positive predictive value was 90%, and negative predictive value was 81%. This index provides the most accurate tool yet reported in the literature for predicting concurrent survival of premature infants. The tool is recommended for use as an index of neonatal condition for low birthweight infants. Its additional use, as a predictor of the likelihood of survival would require time and place specific validation.

Height reduction among prenatally exposed atomic-bomb survivors: a longitudinal study of growth

Using a random coefficient regression model, sex-specific longitudinal analyses of height were made on 801 (392 male and 409 female) atomic-bomb survivors exposed in utero to detect dose effects on standing height. The data set resulted from repeated measurements of standing height of adolescents (age 10-18 y). The dose effect, if any, was assumed to be linear. Gestational ages at the time of radiation exposure were divided into trimesters. Since an earlier longitudinal data analysis has demonstrated radiation effects on height, the emphasis in this paper is on the interaction between dose and gestational age at exposure and radiation effects on the age of occurrence of the adolescent growth spurt. For males, a cubic polynomial growth-curve model applied to the data was affected significantly by radiation. The dose by trimester interaction effect was not significant. The onset of adolescent growth spurt was estimated at about 13 y at 0 Gy. There was no effect of radiation on the adolescent growth spurt. For females, a quadratic polynomial growth-curve model was fitted to the data. The dose effect was significant, while the dose by trimester interaction was again not significant.

Anti-Human T-lymphotropic virus type-I antibodies in atomic-bomb survivors

Adult T-cell leukemia (ATL), induced by human T- lymphotropic virus type-I (HTLV-I), is endemic in Nagasaki, Japan. To investigate the effects of atomic-bomb radiation on development of this specific type of leukemia, 6182 individuals in the Radiation Effects Research Foundation (RERF) Adult Health Study sample in Hiroshima and Nagasaki were examined for positive rate of HTLV-I antibody. Several lymphocyte parameters were also studied for 70 antibody- positive subjects in Nagasaki. The HTLV-I antibody-positive rate was higher in Nagasaki (6.36%) than in Hiroshima (0.79%) and significantly increased with increasing age, but no association was observed with radiation dose. Whether relationship existed between antibody titer levels and radiation dose among antibody-positive subjects was not The frequency of abnormal lymphocytes tended to be higher in antibody-positive subjects than in antibody-negative subjects, and higher in females than in males regardless of radiation dose. The lymphocyte count was lower in antibody-positive subjects than in antibody-negative subjects and lower in female than in male subjects. No evidence was found to suggest that atomic-bomb radiation plays an important role in HTLV-I infection.