Choosing area based socioeconomic measures to monitor social inequalities in low birth weight and childhood lead poisoning: The Public Health Disparities Geocoding Project (US)

STUDY OBJECTIVES

: To determine which area based socioeconomic measures can meaningfully be used, at which level of geography, to monitor socioeconomic inequalities in childhood health in the US.

DESIGN

Cross sectional analysis of birth certificate and childhood lead poisoning registry data, geocoded and linked to diverse area based socioeconomic measures that were generated at three geographical levels: census tract, block group, and ZIP code.

SETTING

Two US states: Massachusetts (1990 population=6,016,425) and Rhode Island (1990 population=1,003,464).

PARTICIPANTS

All births born to mothers ages 15 to 55 years old who were residents of either Massachusetts (1989-1991; n=267,311) or Rhode Island (1987-1993; n=96 138), and all children ages 1 to 5 years residing in Rhode Island who were screened for lead levels between 1994 and 1996 (n=62,514 children, restricted to first test during the study period).

MAIN RESULTS

Analyses of both the birth weight and lead data indicated that: (a) block group and tract socioeconomic measures performed similarly within and across both states, while ZIP code level measures tended to detect smaller effects; (b) measures pertaining to economic poverty detected stronger gradients than measures of education, occupation, and wealth; (c) results were similar for categories generated by quintiles and by a priori categorical cut off points; and (d) the area based socioeconomic measures yielded estimates of effect equal to or augmenting those detected, respectively, by individual level educational data for birth outcomes and by the area based housing measure recommended by the US government for monitoring childhood lead poisoning.

CONCLUSIONS

Census tract or block group area based socioeconomic measures of economic deprivation could be meaningfully used in conjunction with US public health surveillance systems to enable or enhance monitoring of social inequalities in health in the United States.

Familial orthostatic tachycardia due to norepinephrine transporter deficiency

Orthostatic intolerance (OI) or postural tachycardia syndrome (POTS) is a syndrome primarily affecting young females, and is characterized by lightheadedness, palpitations, fatigue, altered mentation, and syncope primarily occurring with upright posture and being relieved by lying down. There is typically tachycardia and raised plasma norepinephrine levels on upright posture, but little or no orthostatic hypotension. The pathophysiology of OI is believed to be very heterogeneous. Most studies of the syndrome have focused on abnormalities in norepinephrine release. Here the hypothesis that abnormal norepinephrine transporter (NET) function might contribute to the pathophysiology in some patients with OI was tested. In a proband with significant orthostatic symptoms and tachycardia, disproportionately elevated plasma norepinephrine with standing, impaired systemic, and local clearance of infused tritiated norepinephrine, impaired tyramine responsiveness, and a dissociation between stimulated plasma norepinephrine and DHPG elevation were found. Studies of NET gene structure in the proband revealed a coding mutation that converts a highly conserved transmembrane domain Ala residue to Pro. Analysis of the protein produced by the mutant cDNA in transfected cells demonstrated greater than 98% reduction in activity relative to normal. NE, DHPG/NE, and heart rate correlated with the mutant allele in this family.

CONCLUSION

These results represent the first identification of a specific genetic defect in OI and the first disease linked to a coding alteration in a Na+/Cl(-)-dependent neurotransmitter transporter. Identification of this mechanism may facilitate our understanding of genetic causes of OI and lead to the development of more effective therapeutic modalities.

Orthostatic intolerance and the postural tachycardia syndrome: genetic and environment pathophysiologies. Neurolab Autonomic Team

Orthostatic intolerance is a common problem for inbound space travelers. There is usually tachycardia on standing but blood pressure may be normal, low or, rarely, elevated. This condition is analogous to the orthostatic intolerance that occurs on Earth in individuals with orthostatic tachycardia, palpitations, mitral valve prolapse, and light-headedness. Our studies during the Neurolab mission indicated that sympathetic nerve traffic is raised in microgravity and that plasma norepinephrine is higher than baseline supine levels but lower than baseline upright levels. A subgroup of patients with familial orthostatic intolerance differ from inbound space travelers in that they have an alanine-to-to-proline mutation at amino acid position 457 in their norepinephrine transporter gene. This leads to poor clearance of norepinephrine from synapses, with consequent raised heart rate. Clinical features of these syndromes are presented.

Absence of deleted in azoospermia (DAZ) genes in spermatozoa of infertile men with somatic DAZ deletions

OBJECTIVE

To determine the presence or absence of the deleted in azoospermia (DAZ) gene clusters in the Y-bearing spermatozoa in semen of severely oligozoospermic men or in testicular biopsy samples of azoospermic men with somatic DAZ deletions.

DESIGN

Prospective study.

SETTING

Academic hospital.

PATIENT(S)

Nineteen patients attending our clinics for therapeutic intracytoplasmic injection of sperm.

INTERVENTION(S)

Peripheral blood lymphocytes were used to obtain somatic DNA for analysis using the polymerase chain reaction. Analysis of chromosomes X and Y and the detection of the DAZ gene clusters were carried out with the fluorescence in situ hybridization technique in spermatozoa remaining after intracytoplasmic sperm injection.

MAIN OUTCOME MEASURE(S)

Presence or absence of the DAZ gene clusters in matched somatic DNA and Y-bearing spermatozoa.

RESULT(S)

Seven patients appeared to have a somatic DAZ deletion. Three-color fluorescence in situ hybridization showed that all Y-bearing spermatozoa examined from these men carried the same deletion.

CONCLUSION(S)

The DAZ deletions present in the seven men would all have been transmitted if they had fathered sons through artificial fertilization techniques using the sperm cells examined in this study.

Unilateral renal agenesis associated with congenital bilateral absence of the vas deferens: phenotypic findings and genetic considerations

An association between congenital bilateral absence of the vas deferens (CBAVD), normal renal anatomy and cystic fibrosis (CF) gene mutations is well established (CF/CBAVD). We postulate that unilateral renal agenesis (URA) and CBAVD (URA/CBAVD) may have a non-CF mutation-mediated genetic basis that leads to abnormal development of the entire mesonephric duct at a very early stage in embryo development (< or =7 weeks). The physical, laboratory and radiographic findings of men with URA/CBAVD (n = 17) and CF/CBAVD (n = 97) were compared; the fertilization and pregnancy rates in the URA/CBAVD population calculated, and the incidence of renal agenesis in immediate family members and offspring of men with URA/CBAVD analysed. No statistical differences could be identified within any of the above comparisons. The fertilization rate for the URA/CBAVD group was 58.2 +/- 26.3%. Eight infants and two fetuses had normal renal anatomy, while one terminated male fetus had bilateral renal and vasal agenesis. Thirty first-order relatives had normal renal units. Anatomical expression of the reproductive ductal derivatives in men with URA/CBAVD and CF/CBAVD was similar, but the phenotypic outcome of the renal portion of the mesonephric duct was different. The potential for transmission of this fatal anomaly reinforces the need for prenatal ultrasounds with all pregnancies involving URA/CBAVD men.

Brain serotonin synthesis rates in rhesus monkeys determined by [11C]alpha-methyl-L-tryptophan and positron emission tomography compared to CSF 5-hydroxyindole-3-acetic acid concentrations

Twelve male, fasted, anesthetized rhesus monkeys were studied with positron emission tomography (PET) and [11C]alpha-methyl-L-tryptophan (alpha MTP) to determine serotonin synthesis rates as described by Diksic et al. (1991). It was expected that the serotonin synthesis rates determined for the whole brain would be correlated with CSF 5-hydroxyindole-3-acetic acid concentrations, a measure of central serotonin turnover, because both measures were obtained at steady state. However, no significant correlation was found. During data analysis, it was noticed that the calculated serotonin synthesis rates were significantly correlated to free plasma tryptophan (TP) concentrations (r = 0.88, p < .001). From repeat scans conducted in six monkeys, it was determined that day-to-day variability in free plasma TP and the percentage of protein binding (average percent difference was 48 and 37%, respectively) produced most of the variability in the calculated serotonin synthesis rates (50%); repeat K images, obtained from the PET data alone, differed by only 11%. Calculated serotonin synthesis rates reported for [11C]alpha MTP PET studies of humans (Nishizawa et al. 1997) and dogs (Diksic et al. 1991) were also highly correlated to reported differences in plasma free TP concentrations. It seems that the [11C]alpha MTP model for the computation of serotonin synthesis rates is very dependent on plasma free TP concentration and that it may not accurately determine actual serotonin synthesis rates.

Fertilization and pregnancy using intentionally cryopreserved testicular tissue as the sperm source for intracytoplasmic sperm injection in 10 men with non-obstructive azoospermia

Testicular tissue extraction (TESE) to obtain spermatozoa for use with intracytoplasmic sperm injection (ICSI) has recently been employed in patients with non-obstructive azoospermia. Standard protocol is to retrieve a new sample of testis tissue on the day of oocyte recovery. Unfortunately, approximately 30% of men will possess no spermatozoa in their tissue, making ICSI an impossibility. We investigated whether testicular tissue that was intentionally obtained well before any planned ICSI cycle and cryopreserved could then serve as an efficacious sperm source in a subsequent ICSI cycle. This study reports on 10 men with non-obstructive azoospermia who did have spermatozoa found within their testis tissue at the time of TESE and who chose to use their frozen samples as the source of spermatozoa for a later cycle of ICSI. In 19 cycles the overall fertilization rate was 48%. Embryo transfer occurred in 89% of cycles. Two couples have achieved pregnancy (one ongoing, one delivered). All patients except one had multiple vials of frozen tissue remaining following their first cycle. This approach is offered as an alternative to repeated testicular tissue sampling, as the availability of spermatozoa is assured prior to the initiation of ovulation induction. This tissue can be harvested at the same time as diagnostic biopsy, thereby minimizing the number of surgical procedures.

Azoospermic men with deletion of the DAZ gene cluster are capable of completing spermatogenesis: fertilization, normal embryonic development and pregnancy occur when retrieved testicular spermatozoa are used for intracytoplasmic sperm injection

Some men with non-obstructive azoospermia harbour fully formed spermatozoa within their testicular tissue that can be used to achieve pregnancy via intracytoplasmic sperm injection (ICSI). Recently, Reijo et al. (1995) provided compelling evidence that the DAZ gene cluster is a strong candidate for one of the elusive azoospermia factors (AZF) located on the long arm of the Y chromosome. The DAZ gene cluster is deleted in 13% of azoospermic men and a small percentage of severely oligozoospermic men. Vertical transmission from father to son of AZF region deletions has also been described. Presumably these fathers were oligozoospermic. This led us to ask whether the azoospermic male with deletions of the AZF/DAZ region can also complete minimal spermatogenesis and whether any spermatozoa found could participate in fertilization, embryo development and pregnancy. Three out of six (50%) of the azoospermic men with AZF/DAZ deletions had spermatozoa identified within their harvested testicular tissue. When these spermatozoa were used for ICSI, fertilization occurred in 36% of injected oocytes. This compared favourably with testicular spermatozoa retrieved from non-obstructive azoospermic men without AZF/DAZ gene deletions. In one case, a twin conception resulted, which represents the first term pregnancy reported using spermatozoa from an AZF/DAZ deleted azoospermic male. Therefore it is necessary to take the possibility of transmission of infertility or sterility to our patients' offspring seriously when utilizing today's reproductive technologies, as spermatogenesis in men with AZF/DAZ deletions is by no means an exceptional occurrence.

Presence of mature sperm in testicular parenchyma of men with nonobstructive azoospermia: prevalence and predictive factors

OBJECTIVES

Hitherto, patients with testicular dysfunction and azoospermia had to resort to adoption, donor sperm insemination, or child-free living. The realization that a proportion of such men harbor spermatozoa in their testicular parenchyma, combined with the ability of intracytoplasmic sperm injection (ICSI) to effect pregnancy with single sperm, has prompted male infertility clinicians to explore testicular sperm extraction (TESE) in this patient population. We sought to investigate the likelihood of finding spermatozoa during TESE from men presenting with nonobstructive azoospermia and to define if any factors existed that were predictive of eventual sperm presence or absence.

METHODS

Thirty patients with nonobstructive azoospermia underwent TESE and simultaneous formal testis biopsy, cytologic analysis, and wet preparation analysis. Tissue obtained from TESE was analyzed according to a rigorous protocol, followed by exhaustive searching by trained embryologists.

RESULTS

Twenty-one patients (70%) had spermatozoa found on testicular tissue analysis. Neither patient age nor follicle-stimulating hormone (FSH) level was predictive of the ability to find sperm. With regard to histologic pattern, 50% of men with Sertoli cell-only, 75% of patients with maturation arrest, and 100% of patients with spermatids seen on histologic analysis had sperm retrieved from their testicular tissue during TESE. Absence of sperm on cytologic smear and wet preparation analysis failed to predict the presence of sperm on formal testicular tissue analysis in 40% of patients.

CONCLUSIONS

Men with nonobstructive azoospermia may have mature spermatozoa present within their testicular parenchyma. Relying on these data, patients should not be excluded from TESE based on serum FSH level, age, prior histopathologic pattern, or cytology/wet preparation results. These figures will allow clinicians to counsel patients with nonobstructive azoospermia informatively regarding TESE and their chances of having testicular sperm retrieved.

The administration of analgesics

1. Maternal informed choice in the administration of analgesics is essential. 2. The placenta is not a barrier to the transfer of drugs to the fetus. 3. All analgesic and anaesthetic drugs are lipid soluble and will cross the placenta. 4. Fetal acidosis increases the accumulation of some drugs in the fetal compartment. 5. Reduced maternal blood flow to the placenta reduces the placental transfer of some drugs.

Oral efficacy of a leukotriene B4 receptor antagonist in colitic cotton-top tamarins

Leukotriene B4 (LTB4) is a potent neutrophil activator and chemotaxin that is present in increased concentrations in the colonic tissue and rectal dialysates of acute ulcerative colitis patients. Cotton-top tamarins (CTTs) with confirmed active colitis were treated with the second generation LTB4 receptor antagonist, SC-53228 ((+)-(S)-7-[3-(2-cyclopropyl-methyl)-3-methoxy-4-[(methylamino) carbonyl]phenoxy]propoxy]-3,4-dihydro-8-propyl-2H-1-benzopyran-2- propanoic acid), 20 mg/kg bodyweight by gavage, twice daily for 56 days. End points were body weights, stool consistency, colonic endoscopy, assay of inflammatory mediators, and haematology and clinical chemistry tests. LTB4 and prostaglandin E (PGE) values were measured in rectal dialysates at pretreatment, 28 day and 56 day time points. LTB4 concentrations were reduced from pretreatment mean (SEM) values of 37.3 (0.8) ng/ml to 3.7 (0.8) ng/ml (p < 0.001) and 2.3 (0.5) ng/ml (p < 0.01) at days 28 and 56, respectively. On the other hand, mucosal protective PGE values remained constant or slightly increased during SC-53228 treatment (pre: 6.9 (2.2) ng/ml; day 28: 6.7 (1.4) ng/ml; day 56: 9.9 (1.6) ng/ml). Furthermore, assessment of a panel of 35 clinical chemistry and haematology parameters throughout the treatment showed there were no significant untoward effects of drug treatment. Six CCTs finished the eight week treatment and five of six gained weight (ranging from 27-121 grams each) while one CTT lost weight (50 g). Stool condition improved in five of six animals while one of six remained unchanged. All CCTs showed dramatic improvement histologically, with no or only minimally active colitis after treatment. The histological changes plus significant weight gains and improvement of stool condition (quality of life parameters) after eight weeks of SC-53228 treatment were remarkable. Furthermore, in follow up biopsies seven months after treatment ceased, three of six CTTs had no active colitis. This is the first time afflicted CTTs have not had recurring colitic exacerbations after a treatment regimen was stopped. It is concluded that in colitic CTTs, SC-53228 has shown both an immediate and a long acting anticolitic activity. It is also concluded that reduced LTB4 concentrations during treatment inhibited neutrophil infiltration of the colonic tissue and this, coupled with the maintenance of mucosal protective prostaglandins, contributed to the dramatic anticolitic efficacy. The treatment was safe over eight weeks. A compound such as SC-53228 may be useful in the medical treatment of human inflammatory bowel disease.

Effects of a safe person on induced distress following a biological challenge in panic disorder with agoraphobia

This study examined the effect of having a safe person present on artificially induced anxiety following a biological challenge among panic-disordered patients. Anxiety symptoms were induced using a 5.5% CO2-inhalation procedure. Panic patients underwent the inhalation procedure either in the presence or absence of their safe person. Nonanxious controls underwent the procedure without a safe person. Panic patients exposed to CO2 without their safe person present reported greater distress, a greater number of catastrophic cognitions, and a greater level of physiological arousal than did panic patients exposed with their safe person. The latter group did not differ from controls on most measures at postexposure. The attenuation of self-reported anxiety and catastrophic cognitions is consistent with the safety-signal theory and the cognitive model of panic, respectively. The results, however, are inconsistent with a biological model of panic.

Reduced inter- and intrasubject variability in cyclosporine pharmacokinetics in renal transplant recipients treated with a microemulsion formulation in conjunction with fasting, low-fat meals, or high-fat meals

This cross-over study compared the pharmacokinetic parameters obtained from cyclosporine (CsA) concentration-time profiles after administration of the corn oil-based soft gel cap (CsA-GC) with those with the microemulsion (CsA-ME) gel cap. Neither the fasting state nor the coadministration of a low- or high-fat breakfast affected the pharmacokinetics of CsA presented in either formulation. Comparisons of the three sets of pharmacokinetic parameters--namely, after fasting or after low-fat or after high-fat diets--demonstrated the CsA-ME formulation to display greater intraindividual reproducibility of the C0 and C12 trough levels (TLs), Cmax, tmax, and area under the concentration-time curve (AUC) than the CsA-GC formulation. Although the degree of interindividual variation in AUC, Cmax and tmax after CsA-ME administration was slightly, but significantly, less than after CsA-GC administration, there was no difference between the two formulations in terms of the customarily monitored C0 or C12 TL values. CsA-ME showed higher correlation coefficients of drug exposure (AUC) with C12 than CsA-GC (0.910 versus 0.712). However, CsA-ME administration resulted in only modest improvement over CsA-GC administration in the relationships between drug dose and C0, C12, or AUC--namely, 0.645 versus 0.496, 0.611 versus 0.517, and 0.700 versus 0.501, respectively. Correlation analysis between individual timed samples and AUC determinations revealed that CsA-ME requires significantly less frequent blood monitoring for prediction of total drug exposure than does CsA-GC. Although the clinical utility of this reproducible pharmacokinetic behavior remains to be demonstrated in the de novo transplant setting, the markedly reduced intraindividual variation produced by administration of CsA-ME will likely improve the accuracy of pretransplant prediction of, and reduce the frequency of subsequent adjustments in, CsA doses.

Effects of a safe person on induced distress following a biological challenge in panic disorder with agoraphobia

This study examined the effect of having a safe person present on artificially induced anxiety following a biological challenge among panic-disordered patients. Anxiety symptoms were induced using a 5.5% CO2-inhalation procedure. Panic patients underwent the inhalation procedure either in the presence or absence of their safe person. Nonanxious controls underwent the procedure without a safe person. Panic patients exposed to CO2 without their safe person present reported greater distress, a greater number of catastrophic cognitions, and a greater level of physiological arousal than did panic patients exposed with their safe person. The latter group did not differ from controls on most measures at postexposure. The attenuation of self-reported anxiety and catastrophic cognitions is consistent with the safety-signal theory and the cognitive model of panic, respectively. The results, however, are inconsistent with a biological model of panic.

Reducing cumulative trauma disorders: use of proper workplace design

1. Cumulative trauma disorder can be reduced by applying four ergonomic approaches: applying anthropometric data, reducing the number of repetitions, reducing the force required, and eliminating awkward postures as much as possible. 2. Selecting the proper work surface height will help reduce fatigue, pain, and discomfort and will allow the employee to be at the right height in relation to the task. Ideally, an adjustable height work surface should be provided that will accommodate all potential users. 3. Prolonged standing and sitting are physically stressful to the body. However, by providing a well designed work area with the appropriate accessories, such as antifatigue mats, ergonomic chairs, and footrests, fatigue and discomfort can be minimized. 4. In addition to providing a properly designed work area, a successful ergonomics program should include training, administrative actions, and exercise programs.

Adult adjustment among high school graduates with mild disabilities

This study investigated the adult adjustment of a statewide random sample of 737 young adults with learning disabilities, 59 labeled behaviorally disordered, and 142 labeled mentally disabled, all graduates of special education resource teacher programs. Results are reported in terms of (a) general status information, such as marital status and living arrangements; (b) information about those competitively employed, such as wages, hours worked per week, and percentage of living expenses paid; and (c) comparison of competitively employed versus unemployed individuals, in terms of high school vocational training and work experiences. Information is also provided on postsecondary education and overall "successful" adult adjustment. Data are compared across disability groups and across gender, where relevant.

Lifting weights

As with engineering improvements, many administrative changes can reduce back injuries. The following administrative steps are recommended: Training for all employees. Increase awareness with posters and meetings. Notify suppliers of reduced weight limit. Job rotation for heavy lifting jobs. Proper maintenance and housekeeping. Use back belts when necessary. Some recommendations should enable employers to begin implementing changes immediately. Other suggestions will require time and money but are worth the investment.