Further evidence of involvement of ITSN1 in autosomal dominant neurodevelopmental disorder

A 5-year-old affected male had following phenotypes: autism, motor stereotypy, developmental regression, staring gaze, absent speech, and behavioral abnormality. The biochemical testing was normal and genetic testing identified a de novo pathogenic variant in ITSN1 gene in the proband. To our knowledge, this is the second report that elucidates the role of ITSN1 gene in an autosomal dominant neurodevelopmental disorder.

Dicarboxylic acylcarnitine biomarkers in peroxisome biogenesis disorders

The peroxisome is an essential eukaryotic organelle with diverse metabolic functions. Inherited peroxisomal disorders are associated with a wide spectrum of clinical outcomes and are broadly divided into two classes, those impacting peroxisome biogenesis (PBD) and those impacting specific peroxisomal factors. Prior studies have indicated a role for acylcarnitine testing in the diagnosis of some peroxisomal diseases through the detection of long chain dicarboxylic acylcarnitine abnormalities (C16-DC and C18-DC). However, there remains limited independent corroboration of these initial findings and acylcarnitine testing for peroxisomal diseases has not been widely adopted in clinical laboratories. To explore the utility of acylcarnitine testing in the diagnosis of peroxisomal disorders we applied a LC-MS/MS acylcarnitine method to study a heterogenous clinical sample set (n = 598) that included residual plasma specimens from nineteen patients with PBD caused by PEX1 or PEX6 deficiency, ranging in severity from lethal neonatal onset to mild late onset forms. Multiple dicarboxylic acylcarnitines were significantly elevated in PBD patients including medium to long chain (C8-DC to C18-DC) species as well as previously undescribed elevations of malonylcarnitine (C3-DC) and very long chain dicarboxylic acylcarnitines (C20-DC and C22-DC). The best performing plasma acylcarnitine biomarkers, C20-DC and C22-DC, were detected at elevated levels in 100% and 68% of PBD patients but were rarely elevated in patients that did not have a PBD. We extended our analysis to residual newborn screening blood spot cards and were able to detect dicarboxylic acylcarnitine abnormalities in a newborn with a PBD caused by PEX6 deficiency. Similar to prior studies, we failed to detect substantial dicarboxylic acylcarnitine abnormalities in blood spot cards from patients with x-linked adrenoleukodystrophy (x-ald) indicating that these biomarkers may have utility in quickly narrowing the differential diagnosis in patients with a positive newborn screen for x-ald. Overall, our study identifies widespread dicarboxylic acylcarnitine abnormalities in patients with PBD and highlights key acylcarnitine biomarkers for the detection of this class of inherited metabolic disease.

Biochemical and molecular confirmation of alkaptonuria in a Sumatran orangutan (Pongo abelii)

A 6-yr-old female orangutan presented with a history of dark urine that turned brown upon standing since birth. Repeated routine urinalysis and urine culture were unremarkable. Urine organic acid analysis showed elevation in homogentisic acid consistent with alkaptonuria. Sequence analysis identified a homozygous missense variant, c.1081G>A (p.Gly361Arg), of the homogentisate 1,2-dioxygenase (HGD) gene. Familial studies, molecular modeling, and comparison to human variant databases support this variant as the underlying cause of alkaptonuria in this orangutan. This is the first report of molecular confirmation of alkaptonuria in a nonhuman primate.

A 2-Year-Old Child with Alazami Syndrome with Newly Reported Findings of Immune Deficiency, Periventricular Nodular Heterotopia, and Stroke; Broadening the Phenotype of Alazami

Alazami syndrome is a rare autosomal recessive neurodevelopmental disorder due to loss-of-function variants in the La ribonucleoprotein 7 (LARP7) gene. Children with Alazami syndrome are most often affected by a combination of primordial dwarfism, intellectual disability, and distinctive facial features. Previous cases have been primarily found in consanguineous families from the Middle East, Asia, and North Africa. We present a 21-month-old Caucasian male from the Midwest United States with nonconsanguineous parents who presented with frequently reported findings of unusual facial features, poor growth, cardiac and genitourinary findings, and developmental delay; less-frequently reported findings, including transient erythroblastopenia of childhood (TEC) and immune deficiency; and never-before reported findings of periventricular nodular heterotopia and stroke. He developed stroke during a hospitalization for Hemophilus influenzae meningitis. The possible contributions of LARP7 to TEC, immune deficiency, brain malformation, and stroke are discussed. Guidelines for the care of Alazami patients are proposed.

An investigation of preceptors' perceptions of behavioral elements of “professionalism” among genetic counseling students

Professionalism in health care is a loosely defined but increasingly studied concept. In genetic counseling, "professional development" expectations for entry-level genetic counselors are described in the "Practice-Based Competencies for Genetic Counselors," but the teaching and evaluation of "professionalism" among genetic counseling students is relatively unexplored. This study investigated program leaders' and clinical supervisors' perceptions of professionalism demonstrated by genetic counseling graduate students to learn about their associated strengths and lapses. Members of program leadership and clinical supervisors at Accreditation Council for Genetic Counseling (ACGC) accredited genetic counseling graduate programs in the United States and Canada were surveyed regarding their observations of genetic counseling students for the years 2017-2019 regarding four domains of professional behavior: integrity, accountability/conscientiousness, teamwork, and patient care, with the Merriam-Webster definition of each behavior provided for each domain. Participants also provided open-text descriptions. Descriptive results showed that the 263 participants found all facets of these professional behaviors to be essential. Patient care had the highest importance and was the domain with the most strengths observed among genetic counseling students. Lapses in professional behavior were identified for self-awareness, time management, and thoroughness. Free responses noted that suggestions or strategies for education about professional behavior from ACGC may improve the professional behavior of genetic counseling students and in turn, genetic counselors. Participants voiced the importance of consideration of diverse professional and cultural backgrounds in setting the expectations for professional behavior among genetic counseling students and genetic counselors so that "professionalism" in genetic counseling is not defined through a White lens. Further investigation into challenges that genetic counseling students face regarding professional behavior during their graduate training and strategies for education about these behaviors will aid in the growth and improvement of the training of genetic counselors. Given the sensitive nature of this topic, portions of this discussion may be triggering for some readers.

Consideration of a metabolic disorder in the differential of mild developmental delay: A case of nonketotic hyperglycinemia revisited 36 years later

We present a 53-year-old male with nonketotic hyperglycinemia (NKH) who presented in decompensated state to our university hospital several months prior to a primary diagnosis of multifocal pneumonia accompanied by reports of seizure-like activity, altered mental status, tremors, and fever. He was initially diagnosed with NKH in his preschool years, over 40 years previously, along with his younger sister. At that time, he had developmental and physical delays (which his sister also experienced). His health course has been relatively uneventful otherwise, as regards decompensation of his disease, and he has not been on the standard regimens of reduced dietary glycine intake along with dextromethorphan and sodium benzoate. Recent molecular confirmation of NKH was completed and both he and his sibling likely have an attenuated form of NKH mediated by the combined effects of their variants. This paper presents what we believe to be report of the oldest surviving individuals with attenuated NKH.

Exploring parents' perceptions of the value of pediatric genetic counseling patient letters: A qualitative study presenting lessons learned

Genetic counseling patient letters are a valuable supplement to genetic counseling practice. As the demand for genetic services increases, improving efficiency in daily tasks such as letter writing could improve genetic counselor workflow. Additionally, understanding the value recipients place on the content of these letters prior to creating efficiencies is essential toward ensuring that the utility of these letters is not lost. To better understand parents' perceptions of the letter's value in the pediatric genetic counseling setting, we employed a qualitative design involving thirteen parents of children who received a patient letter following their diagnosis. Parents participated in a semi-structured focus group, interview, or phone interview, and the data were analyzed using thematic analysis. In addition to gathering perceptions of their child's letter, we sought to learn preferences for letter length, formatting, and level of detail by asking for verbal and written feedback on three different letter formats created for a fictional patient. We used self-determination theory (SDT) framework to create the sample letters, which states that an individual's experience of autonomy, competence, and relatedness can impact their ability to engage in activities. This includes caring for a child with special medical needs. While the findings from this work reinforced the importance of written communication for patients as seen in previous research, this work uncovered three major themes about the letter's value: (a) elements such as readability and content impact parent feelings of autonomy and improve competence moving forward with their child's care; (b) parents value written acknowledgment of the emotional impact of the diagnosis; and (c) parents use the letter as a tool to communicate their child's diagnosis with others. These results can be used for creating comprehensible patient letters that support autonomy, competence, and relatedness.

Home testing for COVID-19: lessons from direct to consumer genetics

On March 11th, 2020, COVID-19 was declared a worldwide pandemic. Publicly available testing has lagged, and tech entrepreneurs have quickly volunteered to fill this gap. Over the last two decades, genetic testing ordered outside of a clinic and without the involvement of a physician has been a way for the average individual to get genetic testing. In this commentary, we discuss the lessons learned from this parallel case from genetics and suggest regulatory caution in establishing direct-to-consumer COVID testing.

Bathing suit ichthyosis: Two Burmese siblings and a review of the literature

Bathing suit ichthyosis (BSI) is a subtype of autosomal recessive congenital ichthyosis (ARCI) characterized by the development of large platelike scales mainly limited to the trunk. It is caused by temperature sensitive variants in transglutaminase 1, encoded by the gene TGM1. We describe a rare case of intrafamilial variation in phenotypic expressivity in two Burmese siblings with BSI that demonstrates the heterogeneity of the disorder within the same family and even in the same individual across time. We also present a concise review of the genotypic spectrum of BSI from 54 cases reported in the literature as evidence that both environmental and additional genetic factors can significantly alter the clinical phenotype.

Topical anaesthesia does not affect cutaneous vasomotor or sudomotor responses in human skin

(1) The effects of local sensory blockade (topical anaesthesia) on eccrine sweat glands and cutaneous circulation are not well understood. This study aimed to determine whether topical lidocaine/prilocaine alters eccrine sweat gland and cutaneous blood vessel responses. (2) Sweating (capacitance hygrometry) was induced via forearm intradermal microdialysis of five acetylcholine (ACh) doses (1 × 10(-4) to 1 × 10(0) m, 10-fold increments) in control and treated forearm sites in six healthy subjects. Nitric oxide-mediated vasodilatory (sodium nitroprusside) and adrenergic vasoconstrictor (noradrenaline) agonists were iontophoresed in lidocaine/prilocaine-treated and control forearm skin in nine healthy subjects during blood flow assessment (laser Doppler flowmetry, expressed as% from baseline cutaneous vascular conductance; CVC; flux/mean arterial pressure). (3) Non-linear regression curve fitting identified no change in the ED50 of ACh-induced sweating after sensory blockade (-1.42 ± 0.23 logM) compared to control (-1.27 ± 0.23 logM; P > .05) or in Emax (0.43 ± 0.08 with, 0.53 ± 0.16 mg cm(-2) min(-1) without lidocaine/prilocaine; P > .05). Sensory blockade did not alter the vasodilator response to sodium nitroprusside (1280 ± 548% change from baseline CVC with, 1204 ± 247% without lidocaine/prilocaine) or vasoconstrictor response to noradrenaline (-14 ± 4% change from baseline CVC with, -22 ± 14% without lidocaine/prilocaine; P > 0.05). (4) Cutaneous sensory blockade does not appear to alter nitric oxide-mediated vasodilation, adrenergic vasoconstriction, or cholinergic eccrine sweating dose-response sensitivity or responsiveness to maximal dose. Thus, lidocaine/prilocaine treatment should not affect sweat gland function or have blood flow implications for subsequent research protocols or clinical procedures.

Colloid volume loading does not mitigate decreases in central blood volume during simulated haemorrhage while heat stressed

Heat stress results in profound reductions in the capacity to withstand a simulated haemorrhagic challenge; however, this capacity is normalized if the individual is volume loaded prior to the challenge. The present study tested the hypothesis that volume loading during passive heat stress attenuates the reduction in regional blood volumes during a simulated haemorrhagic challenge imposed via lower-body negative pressure (LBNP). Seven subjects underwent 30 mmHg LBNP while normothermic, during passive heat stress (increased internal temperature ∼1◦C), and while continuing to be heated after intravenous colloid volume loading (11 ml kg⁻¹). Relative changes in torso and regional blood volumes were determined by gamma camera imaging with technetium-99m labelled erythrocytes. Heat stress reduced blood volume in all regions (ranging from 7 to 16%), while subsequent volume loading returned those values to normothermic levels. While normothermic,LBNP reduced blood volume in all regions (torso: 22 ± 8%; heart: 18 ± 6%; spleen: 15 ± 8%). During LBNP while heat stressed, the reductions in blood volume in each region were markedly greater when compared to LBNP while normothermic (torso: 73 ± 2%; heart: 72 ± 3%; spleen: 72 ± 5%, all P<0.001 relative to normothermia). Volume loading during heat stress did not alter the extent of the reduction in these blood volumes to LBNP relative to heat stress alone (torso: 73 ± 1%; heart: 72 ± 2%; spleen: 74 ± 3%, all P>0.05 relative to heat stress alone). These data suggest that blood volume loading during passive heat stress (via 11 ml kg⁻¹ of a colloid solution) normalizes regional blood volumes in the torso, but does not mitigate the reduction in central blood volume during a simulated haemorrhagic challenge combined with heat stress.

Insufficient cutaneous vasoconstriction leading up to and during syncopal symptoms in the heat stressed human

As much as 50% of cardiac output can be distributed to the skin in the hyperthermic human, and therefore the control of cutaneous vascular conductance (CVC) becomes critical for the maintenance of blood pressure. Little is known regarding the magnitude of cutaneous vasoconstriction in profoundly hypotensive individuals while heat stressed. This project investigated the hypothesis that leading up to and during syncopal symptoms associated with combined heat and orthostatic stress, reductions in CVC are inadequate to prevent syncope. Using a retrospective study design, we evaluated data from subjects who experienced syncopal symptoms during lower body negative pressure (N = 41) and head-up tilt (N = 5). Subjects were instrumented for measures of internal temperature, forearm skin blood flow, arterial pressure, and heart rate. CVC was calculated as skin blood flow/mean arterial pressure × 100. Data were obtained while subjects were normothermic, immediately before an orthostatic challenge while heat stressed, and at 5-s averages for the 2 min preceding the cessation of the orthostatic challenge due to syncopal symptoms. Whole body heat stress increased internal temperature (1.25 ± 0.3°C; P < 0.001) and CVC (29 ± 20 to 160 ± 58 CVC units; P < 0.001) without altering mean arterial pressure (83 ± 7 to 82 ± 6 mmHg). Mean arterial pressure was reduced to 57 ± 9 mmHg (P < 0.001) immediately before the termination of the orthostatic challenge. At test termination, CVC decreased to 138 ± 61 CVC units (P < 0.001) relative to before the orthostatic challenge but remained approximately fourfold greater than when subjects were normothermic. This negligible reduction in CVC during pronounced hypotension likely contributes to reduced orthostatic tolerance in heat-stressed humans. Given that lower body negative pressure and head-up tilt are models of acute hemorrhage, these findings have important implications with respect to mechanisms of compromised blood pressure control in the hemorrhagic individual who is also hyperthermic (e.g., military personnel, firefighters, etc.).

Effect of volume loading on the Frank-Starling relation during reductions in central blood volume in heat-stressed humans

During reductions in central blood volume while heat stressed, a greater decrease in stroke volume (SV) for a similar decrease in ventricular filling pressure, compared to normothermia, suggests that the heart is operating on a steeper portion of a Frank-Starling curve. If so, volume loading of heat-stressed individuals would shift the operating point to a flatter portion of the heat stress Frank-Starling curve thereby attenuating the reduction in SV during subsequent decreases in central blood volume. To investigate this hypothesis, right heart catheterization was performed in eight males from whom pulmonary capillary wedge pressure (PCWP), central venous pressure and SV (via thermodilution) were obtained while central blood volume was reduced via lower-body negative pressure (LBNP) during normothermia, whole-body heating (increase in blood temperature 1 degrees C), and during whole-body heating after intravascular volume expansion. Volume expansion was accomplished by administration of a combination of a synthetic colloid (HES 130/0.4, Voluven) and saline. Before LBNP, SV was not affected by heating (122 +/- 30 ml; mean +/- s.d.) compared to normothermia (110 +/- 20 ml; P = 0.06). However, subsequent volume loading increased SV to 143 +/- 29 ml (P = 0.003). LBNP provoked a larger decrease in SV relative to the decrease in PCWP during heating (8.6 +/- 1.9 ml mmHg(1)) compared to normothermia (4.5 +/- 3.0 ml mmHg(1), P = 0.02). After volume loading while heat stressed, the reduction in the SV to PCWP ratio during LBNP was comparable to that observed during normothermia (4.8 +/- 2.3 ml mmHg(1); P = 0.78). These data support the hypothesis that a Frank-Starling mechanism contributes to compromised blood pressure control during simulated haemorrhage in heat-stressed individuals, and extend those findings by showing that volume infusion corrects this deficit by shifting the operating point to a flatter portion of the heat stress Frank-Starling curve.

Effect of thermal stress on Frank-Starling relations in humans

The Frank-Starling 'law of the heart' is implicated in certain types of orthostatic intolerance in humans. Environmental conditions have the capacity to modulate orthostatic tolerance, where heat stress decreases and cooling increases orthostatic tolerance. The objective of this project was to test the hypothesis that heat stress augments and cooling attenuates orthostatic-induced decreases in stroke volume (SV) via altering the operating position on a Frank-Starling curve. Pulmonary artery catheters were placed in 11 subjects for measures of pulmonary capillary wedge pressure (PCWP) and SV (thermodilution derived cardiac output/heart rate). Subjects experienced lower-body negative-pressure (LBNP) of 0, 15 and 30 mmHg during normothermia, skin-surface cooling (decrease in mean skin temperature of 4.3 +/- 0.4 degrees C (mean +/- s.e.m.) via perfusing 16 degrees C water through a tubed-lined suit), and whole-body heating (increase in blood temperature of 1.0 +/- 0.1 degrees C via perfusing 46 degrees C water through the suit). SV was 123 +/- 8, 121 +/- 10, 131 +/- 7 ml prior to LBNP, during normothermia, skin-surface cooling, and whole-body heating, respectfully (P = 0.20). LBNP of 30 mmHg induced greater decreases in SV during heating (-48.7 +/- 6.7 ml) compared to normothermia (-33.2 +/- 7.4 ml) and to cooling (-10.3 +/- 2.9 ml; all P < 0.05). Relating PCWP to SV indicated that cooling values were located on the flatter portion of a Frank-Starling curve because of attenuated decreases in SV per decrease in PCWP. In contrast, heating values were located on the steeper portion of a Frank-Starling curve because of augmented decreases in SV per decrease in PCWP. These data suggest that a Frank-Starling mechanism may contribute to improvements in orthostatic tolerance during cold stress and orthostatic intolerance during heat stress.

Effects of passive heating on central blood volume and ventricular dimensions in humans

Mixed findings regarding the effects of whole-body heat stress on central blood volume have been reported. This study evaluated the hypothesis that heat stress reduces central blood volume and alters blood volume distribution. Ten healthy experimental and seven healthy time control (i.e. non-heat stressed) subjects participated in this protocol. Changes in regional blood volume during heat stress and time control were estimated using technetium-99m labelled autologous red blood cells and gamma camera imaging. Whole-body heating increased internal temperature (> 1.0 degrees C), cutaneous vascular conductance (approximately fivefold), and heart rate (52 +/- 2 to 93 +/- 4 beats min(-1)), while reducing central venous pressure (5.5 +/- 07 to 0.2 +/- 0.6 mmHg) accompanied by minor decreases in mean arterial pressure (all P < 0.05). The heat stress reduced the blood volume of the heart (18 +/- 2%), heart plus central vasculature (17 +/- 2%), thorax (14 +/- 2%), inferior vena cava (23 +/- 2%) and liver (23 +/- 2%) (all P </= 0.005 relative to time control subjects). Radionuclide multiple-gated acquisition assessment revealed that heat stress did not significantly change left ventricular end-diastolic volume, while ventricular end-systolic volume was reduced by 24 +/- 6% of pre-heat stress levels (P < 0.001 relative to time control subjects). Thus, heat stress increased left ventricular ejection fraction from 60 +/- 1% to 68 +/- 2% (P = 0.02). We conclude that heat stress shifts blood volume from thoracic and splanchnic regions presumably to aid in heat dissipation, while simultaneously increasing heart rate and ejection fraction.

Effects of heat and cold stress on central vascular pressure relationships during orthostasis in humans

Central venous pressure (CVP) provides information regarding right ventricular filling pressure, but is often assumed to reflect left ventricular filling pressure. It remains unknown whether this assumption is correct during thermal challenges when CVP is elevated during skin-surface cooling or reduced during whole-body heating. The primary objective of this study was to test the hypothesis that changes in CVP reflect those in left ventricular filling pressure, as expressed by pulmonary capillary wedge pressure (PCWP), during lower-body negative pressure (LBNP) while subjects are normothermic, during skin-surface cooling, and during whole-body heating. In 11 subjects, skin-surface cooling was imposed by perfusing 16 degrees C water through a water-perfused suit worn by each subject, while heat stress was imposed by perfusing 47 degrees C water through the suit sufficient to increase internal temperature 0.95 +/- 0.07 degrees C (mean +/- s.e.m.). While normothermic, CVP was 6.3 +/- 0.2 mmHg and PCWP was 9.5 +/- 0.3 mmHg. These pressures increased during skin-surface cooling (7.8 +/- 0.2 and 11.1 +/- 0.3 mmHg, respectively; P < 0.05) and decreased during whole-body heating (3.6 +/- 0.1 and 6.5 +/- 0.2 mmHg, respectively; P < 0.05). The decrease in CVP with LBNP was correlated with the reduction in PCWP during normothermia (r = 0.93), skin-surface cooling (r = 0.91), and whole-body heating (r = 0.81; all P < 0.001). When these three thermal conditions were combined, the overall r value between CVP and PCWP was 0.92. These data suggest that in the assessed thermal conditions, CVP appropriately tracks left ventricular filling pressure as indexed by PCWP. The correlation between these values provides confidence for the use of CVP in studies assessing ventricular preload during thermal and combined thermal and orthostatic perturbations.

Evidence of a myogenic response in vasomotor control of forearm and palm cutaneous microcirculations

Previous investigations of autoregulatory mechanisms in the control of skin blood flow suffer from the possibility of interfering effects of the autonomic nervous system. To address this question, in 11 subjects cutaneous vascular responses were measured during acute changes in perfusion pressure (using Valsalva maneuver; VM) before and after ganglionic blockade via systemic trimethaphan infusion. Cutaneous vascular conductance at baseline (CVCbase) and during the last 5 s of the VM (CVCVM) were measured from forearm (nonglabrous) and palm (glabrous) skin. During the VM without ganglionic blockade, compared with CVCbase, CVCVM decreased significantly at the palm [0.79 ± 0.17 to 0.55 ± 0.17 arbitrary units (AU)/mmHg; P = 0.002] but was unchanged at the forearm (0.13 ± 0.02 to 0.16 ± 0.02 AU/mmHg; P = 0.50). After ganglionic blockade, VM induced pronounced decreases in perfusion pressure, which resulted in significant increases in CVCVM at both forearm (0.19 ± 0.03 to 0.31 ± 0.07 AU/mmHg; P = 0.008) and palm (1.84 ± 0.29 to 2.76 ± 0.63 AU/mmHg; P = 0.003) sites. These results suggest that, devoid of autonomic control, both glabrous and nonglabrous skin are capable of exhibiting vasomotor autoregulation during pronounced reductions in perfusion pressure.

Prolonged head-down tilt exposure reduces maximal cutaneous vasodilator and sweating capacity in humans

Cutaneous vasodilation and sweat rate are reduced during a thermal challenge after simulated and actual microgravity exposure. The effects of microgravity exposure on cutaneous vasodilator capacity and on sweat gland function are unknown. The purpose of this study was to test the hypothesis that simulated microgravity exposure, using the 6 degrees head-down tilt (HDT) bed rest model, reduces maximal forearm cutaneous vascular conductance (FVC) and sweat gland function and that exercise during HDT preserves these responses. To test these hypotheses, 20 subjects were exposed to 14 days of strict HDT bed rest. Twelve of those subjects exercised (supine cycle ergometry) at 75% of pre-bed rest heart rate maximum for 90 min/day throughout HDT bed rest. Before and after HDT bed rest, maximal FVC was measured, via plethysmography, by heating the entire forearm to 42 degrees C for 45 min. Sweat gland function was assessed by administering 1 x 10(-6) to 2 M acetylcholine (9 doses) via intradermal microdialysis while simultaneously monitoring sweat rate over the microdialysis membranes. In the nonexercise group, maximal FVC and maximal stimulated sweat rate were significantly reduced after HDT bed rest. In contrast, these responses were unchanged in the exercise group. These data suggest that 14 days of simulated microgravity exposure, using the HDT bed rest model, reduces cutaneous vasodilator and sweating capacity, whereas aerobic exercise training during HDT bed rest preserves these responses.

Community-based interventions to reduce low income, African American women's risk of sexually transmitted diseases: a randomized controlled trial of three theoretical models

A community-based sample of disadvantaged African American women (n = 445) was recruited to participate in 1 of 3 theoretically driven experimental interventions based on either the theory of gender and power, social learning theory, or cognitive behavioral theory. Intervention outcomes were compared with a waiting list control condition. From baseline to postintervention, women in the experimental interventions showed differential change on cognitive indices (knowledge and attitudes) and skill acquisition (partner negotiation skills, correct condom application, lubricant selection, and information-provision to social networks) whereas control participants were unchanged. Women in the 3 experimental interventions also completed follow-up assessments for 1 year following the interventions. In all 3 experimental conditions, condom use increased relative to the control group and there were no differences between the experimental interventions. Women who participated in one of the theoretically grounded interventions continued to increase condom use over the following year. Women entering new relationships reported significantly more condom use than did women who remained in ongoing relationships. The findings suggest that intervention models that have proven effective for women who engage in high-risk behavior may be less effective for women in established relationships for whom risk is primarily derived from the extrarelationship behavior of their partners.

A case-control study of beliefs and behaviors associated with sexually transmitted disease occurrence in Estonia

BACKGROUND

Epidemiologic data document rapidly increasing sexually transmitted disease (STD) rates throughout Eastern Europe.

GOAL

This case-control study was designed to delineate factors contributing to the STD epidemic in Estonia.

STUDY DESIGN

For this study, 189 study participants and 112 control subjects completed a behavioral questionnaire and underwent testing for Neisseria gonorrhoeae, Chlamydia trachomatis, and Treponema pallidum.

RESULTS

The prevalence of STDs among the control subjects was 32%. Although the participants believed that condoms prevent STDs, only 17% reported consistent use. Methods believed to prevent transmission included washing the genitals (65%), urinating (26%), douching (35%), and using oral contraceptives (19%). An interaction between sex and travel outside Estonia (odds ratio, 0.1; 95% CI, 0-0.7) reflects the fact that males with STDs were more likely to report travel (46% of participants and 45.5% of control subjects with STD) than were those without STD (16.1% of controls without STD).

CONCLUSIONS

STD rates are related to high-risk sexual behavior among males traveling outside of Estonia. Intervention is needed to promote understanding of disease transmission dynamics in this area, and to decrease sexual risk behavior, particularly in the context of travel.

Repair of DNA strand breaks by the overlapping functions of lesion-specific and non-lesion-specific DNA 3' phosphatases

In Saccharomyces cerevisiae, the apurinic/apyrimidinic (AP) endonucleases Apn1 and Apn2 act as alternative pathways for the removal of various 3'-terminal blocking lesions from DNA strand breaks and in the repair of abasic sites, which both result from oxidative DNA damage. Here we demonstrate that Tpp1, a homologue of the 3' phosphatase domain of polynucleotide kinase, is a third member of this group of redundant 3' processing enzymes. Unlike Apn1 and Apn2, Tpp1 is specific for the removal of 3' phosphates at strand breaks and does not possess more general 3' phosphodiesterase, exonuclease, or AP endonuclease activities. Deletion of TPP1 in an apn1 apn2 mutant background dramatically increased the sensitivity of the double mutant to DNA damage caused by H2O2 and bleomycin but not to damage caused by methyl methanesulfonate. The triple mutant was also deficient in the repair of 3' phosphate lesions left by Tdp1-mediated cleavage of camptothecin-stabilized Top1-DNA covalent complexes. Finally, the tpp1 apn1 apn2 triple mutation displayed synthetic lethality in combination with rad52, possibly implicating postreplication repair in the removal of unrepaired 3'-terminal lesions resulting from endogenous damage. Taken together, these results demonstrate a clear role for the lesion-specific enzyme, Tpp1, in the repair of a subset of DNA strand breaks.

Absence of arterial baroreflex modulation of skin sympathetic activity and sweat rate during whole-body heating in humans

1. Prior findings suggest that baroreflexes are capable of modulating skin blood flow, but the effects of baroreceptor loading/unloading on sweating are less clear. Therefore, this project tested the hypothesis that pharmacologically induced alterations in arterial blood pressure in heated humans would lead to baroreflex-mediated changes in both skin sympathetic nerve activity (SSNA) and sweat rate. 2. In seven subjects mean arterial blood pressure was lowered (approximately 8 mmHg) and then raised (approximately 13 mmHg) by bolus injections of sodium nitroprusside and phenylephrine, respectively. Moreover, in a separate protocol, arterial blood pressure was reduced via steady-state administration of sodium nitroprusside. In both normothermia and heat-stress conditions the following responses were monitored: sublingual and mean skin temperatures, heart rate, beat-by-beat blood pressure, skin blood flow (laser-Doppler flowmetry), local sweat rate and SSNA (microneurography from peroneal nerve). 3. Whole-body heating increased skin and sublingual temperatures, heart rate, cutaneous blood flow, sweat rate and SSNA, but did not change arterial blood pressure. Heart rate was significantly elevated (from 74 +/- 3 to 92 +/- 4 beats x min(-1); P < 0.001) during bolus sodium nitroprusside-induced reductions in blood pressure, and significantly reduced (from 92 +/- 4 to 68 +/- 4 beats x min(-1); P < 0.001) during bolus phenylephrine-induced elevations in blood pressure, thereby demonstrating normal baroreflex function in these subjects. 4. Neither SSNA nor sweat rate was altered by rapid (bolus infusion) or sustained (steady-state infusion) changes in blood pressure regardless of the thermal condition. 5. These data suggest that SSNA and sweat rate are not modulated by arterial baroreflexes in normothermic or moderately heated individuals.

Baroreflex modulation of muscle sympathetic nerve activity during posthandgrip muscle ischemia in humans

To identify whether muscle metaboreceptor stimulation alters baroreflex control of muscle sympathetic nerve activity (MSNA), MSNA, beat-by-beat arterial blood pressure (Finapres), and electrocardiogram were recorded in 11 healthy subjects in the supine position. Subjects performed 2 min of isometric handgrip exercise at 40% of maximal voluntary contraction followed by 2.5 min of posthandgrip muscle ischemia. During muscle ischemia, blood pressure was lowered and then raised by intravenous bolus infusions of sodium nitroprusside and phenylephrine HCl, respectively. The slope of the relationship between MSNA and diastolic blood pressure was more negative (P < 0.001) during posthandgrip muscle ischemia (-201.9 +/- 20.4 units. beat(-1). mmHg(-1)) when compared with control conditions (-142.7 +/- 17.3 units. beat(-1). mmHg(-1)). No significant change in the slope of the relationship between heart rate and systolic blood pressure was observed. However, both curves shifted during postexercise ischemia to accommodate the elevation in blood pressure and MSNA that occurs with this condition. These data suggest that the sensitivity of baroreflex modulation of MSNA is elevated by muscle metaboreceptor stimulation, whereas the sensitivity of baroreflex of modulate heart rate is unchanged during posthandgrip muscle ischemia.

Brief report: condom use consistency associated with beliefs regarding HIV disease transmission among women receiving HIV antiretroviral therapy

OBJECTIVE

To ascertain whether condom use consistency is associated with beliefs regarding a decreased likelihood of HIV transmission as a function of taking antiretroviral therapy.

DESIGN

Cross-sectional analysis of HIV-positive women from Brooklyn (NY) enrolled in the Women's Interagency HIV Study (WIHS) who were taking any form of antiretroviral therapy at the time of data collection.

METHODS

Between February and October, 1999, 145 HIV-positive eligible women participated in a structured, face-to-face interview. Interviews assessed attitudes and behaviors related to antiretroviral therapy and sexual risk behavior in the 6 months since a previous study visit.

RESULTS

Over three fourths of the study sample (77%) disagreed with a statement that being on antiretroviral therapy decreases the chances of transmitting HIV to others. After controlling for number of sexual partners and HIV serostatus of partners, women reporting no association between HIV therapy and disease infectiousness were over three times more likely to report consistent condom use (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.2-8.3; p <.05).

CONCLUSIONS

Antiretroviral therapy may be associated with increased risk behavior when it is believed that regimens may decrease the risk of disease transmission. Education regarding potential deleterious consequences of inconsistent condom use should be part of ongoing HIV care.

Digital mammography: observer performance study of the effects of pixel size on the characterization of malignant and benign microcalcifications

RATIONALE AND OBJECTIVES

The authors performed this study to evaluate the effects of pixel size on the characterization of mammographic microcalcifications by radiologists.

MATERIALS AND METHODS

Two-view mammograms of 112 microcalcification clusters were digitized with a laser scanner at a pixel size of 35 microm. Images with pixel sizes of 70, 105, and 140 microm were derived from the 35-microm-pixel size images by averaging neighboring pixels. The malignancy or benignity of the microcalcifications had been determined with findings at biopsy or 2-year follow-up. Region-of-interest images containing the microcalcifications were printed with a laser imager. Seven radiologists participated in a receiver operating characteristic (ROC) study to estimate the likelihood of malignancy. The classification accuracy was quantified with the area under the ROC curve (Az). The statistical significance of the differences in the Az values for different pixel sizes was estimated with the Dorfman-Berbaum-Metz method and the Student paired t test. The variance components were analyzed with a bootstrap method.

RESULTS

The higher-resolution images did not result in better classification; the average Az with a pixel size of 35 microm was lower than that with pixel sizes of 70 and 105 microm. The differences in Az between different pixel sizes did not achieve statistical significance.

CONCLUSION

Pixel sizes in the range studied do not have a strong effect on radiologists' accuracy in the characterization of microcalcifications. The low specificity of the image features of microcalcifications and the large interobserver and intraobserver variabilities may have prevented small advantages in image resolution from being observed.

Uncoupling of 3'-phosphatase and 5'-kinase functions in budding yeast. Characterization of Saccharomyces cerevisiae DNA 3'-phosphatase (TPP1)

Polynucleotide kinase is a bifunctional enzyme containing both DNA 3'-phosphatase and 5'-kinase activities seemingly suited to the coupled repair of single-strand nicks in which the phosphate has remained with the 3'-base. We show that the yeast Saccharomyces cerevisiae is able to repair transformed dephosphorylated linear plasmids by non-homologous end joining with considerable efficiency independently of the end-processing polymerase Pol4p. Homology searches and biochemical assays did not reveal a 5'-kinase that would account for this repair, however. Instead, open reading frame YMR156C (here named TPP1) is shown to encode only a polynucleotide kinase-type 3'-phosphatase. Tpp1p bears extensive similarity to the ancient L-2-halo-acid dehalogenase and DDDD phosphohydrolase superfamilies, but is specific for double-stranded DNA. It is present at high levels in cell extracts in a functional form and so does not represent a pseudogene. Moreover, the phosphatase-only nature of this gene is shared by Saccharomyces mikatae YMR156C and Arabidopsis thaliana K15M2.3. Repair of 3'-phosphate and 5'-hydroxyl lesions is thus uncoupled in budding yeast as compared with metazoans. Repair of transformed dephosphorylated plasmids, and 5'-hydroxyl blocking lesions more generally, likely proceeds by a cycle of base removal and resynthesis.

Self-reported zidovudine adherence among pregnant women with human immunodeficiency virus infection in four US states

OBJECTIVE

Our purpose was to identify clinical and psychosocial factors associated with rates of prenatal zidovudine use and adherence among human immunodeficiency virus-infected pregnant women.

STUDY DESIGN

Two hundred sixty-four women completed 2 interviews between October 1996 and November 1998 at prenatal clinics in Miami, Florida; Brooklyn, New York; Connecticut; and North Carolina. Interviews took place after 24 weeks' gestation and then between 32 weeks and delivery.

RESULTS

Prenatal zidovudine had been prescribed for 94% of the women, 37% of whom received monotherapy. Among women taking zidovudine, 20% reported incomplete adherence. In multivariate analyses having missed zidovudine doses was positively associated with prenatal illicit drug use (odds ratio, 3.49; 95% confidence interval, 1.30-9.42; P <.05) and missing prenatal vitamins (odds ratio, 2.71; 95% confidence interval, 1.30-5.67; P <.01).

CONCLUSIONS

Zidovudine therapies have been successfully implemented in prenatal care settings in the United States. The success of these therapies may be limited among some patients by incomplete regimen adherence, particularly among illicit drug users.

Barriers to universal prenatal HIV testing in 4 US locations in 1997

OBJECTIVES

We determined rates of prenatal HIV testing and investigated barriers to testing.

METHODS

We surveyed 1362 representative parturient women from 7 hospitals in 4 locations of the United States.

RESULTS

Overall, 89.9% of women reported being offered HIV testing and 69.6% reported being tested. Proportions of women not offered testing differed by location (range = 5.2%-16.3%), as did proportions not tested (range = 12.2%-54.4%). Among women who perceived that their clinicians had not recommended testing, 41.7% were tested, compared with 92.8% of women who perceived a strong recommendation (P < .05). Private insurance for prenatal care was also associated with not being tested. Women gave multiple reasons for not being tested, most commonly not being at risk, having been tested recently, and the test's not being offered or recommended, cited by 55.3%, 39.1% and 11.1% of women, respectively.

CONCLUSIONS

Although most parturient women were offered a prenatal HIV test and got tested, testing proportions did not reach national goals and differed significantly by location and payment status. Concern about testing consequences was not a major barrier. Perception of clinicians' recommendations strongly influenced testing. Changing provider practices will be essential to implementing universal prenatal HIV testing.

Infant birth weight among women with or at high risk for HIV infection: the impact of clinical, behavioral, psychosocial, and demographic factors

The purpose of these analyses was to provide a prospective examination of the impact of HIV on birth weight using clinical, behavioral, psychosocial, and demographic correlates. HIV-positive (n = 319) and HIV-negative (n = 220) pregnant women matched for HIV risk factors (i.e., drug use and sexual risk behaviors) were interviewed during the 3rd trimester of pregnancy and 6 weeks postpartum. Medical chart reviews were also conducted for the HIV-seropositive pregnant women to verify pregnancy-related and birth outcome data. In a logistic regression analysis, model chi2(9, N = 518) = 124.8, p < .001, controlling for parity and gestational age, women who were HIV seropositive were 2.6 times more likely to have an infant with low birth weight. In addition, Black women and those who did not live with their partners were more than 2 times as likely to have infants with low birth weight, and those who smoked were 3.2 times more likely to have infants with low birth weight. Knowing that women with HIV, those who are Black, and those not living with a partner are at highest risk for adverse birth outcomes can help those in prenatal clinics and HIV specialty clinics to target resources and develop prevention interventions. This is particularly important for women with HIV because birth weight is associated with risk of HIV transmission from mother to child.

Domestic violence reported by women attending a sexually transmitted disease clinic

BACKGROUND

Domestic violence occurs across all social, demographic, and economic strata of society, though women who report it are disproportionately young, unmarried, live with a male friend or family member other than a husband, engage in substance abuse, and are poor.

GOAL

To assess the prevalence of domestic violence among a sample of women presenting for care at a sexually transmitted disease (STD) clinic, and to identify behavioral and clinical correlates of domestic violence in this group.

STUDY DESIGN

Women attending an inner-city STD clinic were asked to complete a self-administered questionnaire that ascertained demographic, clinical, and behavioral information. Questions regarding recent and lifetime physical and verbal abuse by a social intimate were included. Standard diagnostic tests and therapy for a variety of genitourinary infections were provided when indicated as a matter of routine care.

RESULTS

Three hundred and seventy-five female clinic attendees completed the questionnaire. One hundred and forty one (37.6%) women reported ever having experienced physical assault by an intimate, and 123 (32.8%) reported verbal threats of violence. Fifty-eight (15.5%) women reported at least one episode of physical abuse in the year preceding participation. A report of physical violence was associated with drug use, STD history, and a history of a serious medical condition (P < 0.05).

CONCLUSION

The high prevalence of domestic violence among women seeking care at an inner-city STD clinic suggests that these sites may be important for the detection of abuse victims. Clinic staff should be trained to inquire about domestic violence. On-site or referred resources (e.g., legal, social, clinical) should be made available to these women.

Infant birth weight among women with or at high risk for HIV infection: the impact of clinical, behavioral, psychosocial, and demographic factors

The purpose of these analyses was to provide a prospective examination of the impact of HIV on birth weight using clinical, behavioral, psychosocial, and demographic correlates. HIV-positive (n = 319) and HIV-negative (n = 220) pregnant women matched for HIV risk factors (i.e., drug use and sexual risk behaviors) were interviewed during the 3rd trimester of pregnancy and 6 weeks postpartum. Medical chart reviews were also conducted for the HIV-seropositive pregnant women to verify pregnancy-related and birth outcome data. In a logistic regression analysis, model chi2(9, N = 518) = 124.8, p < .001, controlling for parity and gestational age, women who were HIV seropositive were 2.6 times more likely to have an infant with low birth weight. In addition, Black women and those who did not live with their partners were more than 2 times as likely to have infants with low birth weight, and those who smoked were 3.2 times more likely to have infants with low birth weight. Knowing that women with HIV, those who are Black, and those not living with a partner are at highest risk for adverse birth outcomes can help those in prenatal clinics and HIV specialty clinics to target resources and develop prevention interventions. This is particularly important for women with HIV because birth weight is associated with risk of HIV transmission from mother to child.

The influence of HIV-related knowledge and exposure fears on behavior change and incident STDs

Using a sample of 678 HIV-seronegative women, we measured self-reports of HIV-related cognitions, specifically knowledge, perceived exposure risks, and outcome expectations. We also ascertained prevalent and incident bacterial STDs and measured self-reports of behavioral risk reductions. We tested for associations between (a) cognitions and STD prevalence, (b) cognitions and incident STDs, (c) cognitions and behavioral risk reductions, and (d) risk reductions and incident STDs. Symptom knowledge was associated with lower prevalence, but not incidence. Beliefs in the efficacy of risk reductions showed a protective effect against incident STDs. Perceived exposure risk and symptom knowledge were associated with risk reduction behavior.

Effect of precooling on physical performance in multiple sclerosis

Many individuals with MS experience heat sensitivity that may be associated with transient increases in the frequency of clinical signs and symptoms. Although physical activity may be beneficial for those with MS, induced thermal loads may preclude participation in exercise and other daily activities. This project was designed to evaluate the effects of precooling on physical function. Six thermosensitive MS patients were studied. Participants performed a graded exercise test to determine maximal oxygen uptake (VO2max) on a combined arm-leg ergometer. Thermal load was induced by 30 min of exercise under noncooled and precooled conditions at a workrate corresponding to 60% VO2max. Precooling consisted of 30 min lower body immersion in 16 - 17 degrees C water. Fatigue and 25-ft walk performance were assessed before, immediately after, and 30 min following exercise. No treatment differences in VO2 were observed. Rectal temperature, heart rate, and rating of perceived exertion (RPE) were significantly lower during the precooled exercise trial compared to the noncooled trial. Immediately following exercise, 25-ft walk performance and fatigue scores showed significantly greater deterioration in the noncooled condition. Precooling was effective in preventing gains in core temperature with physical work and may allow heat-sensitive individuals with MS to exercise with greater physical comfort.

Acceptance of HIV testing during prenatal care. Perinatal Guidelines Evaluation Project

OBJECTIVE

The purpose of this study was to assess the factors associated with acceptance of HIV testing during pregnancy on the part of women receiving prenatal care at public clinics.

METHODS

Trained interviewers recruited and interviewed 1,357 women receiving prenatal care at clinics in Florida, Connecticut, and New York City.

RESULTS

Eighty-six percent of participants reported having been tested or having signed a consent form to be tested. Acceptance of testing was found to be related to strong beliefs about the benefits of testing, knowledge about vertical transmission, perceived provider endorsement of testing, and social support. Women who declined testing said they did so because they did not perceive themselves to be at risk for HIV (21%) or they faced administrative difficulties (16%) with some aspect of the testing process (for example, scheduling, limited availability of pre-test counselors).

CONCLUSIONS

Acceptance rates can be increased when women understand the modes of vertical transmission and the role of medication regimens in preventing transmission; believe that prenatal identification of HIV can promote the health of mother and child; and perceive their providers as strongly endorsing testing. These points can be woven into a brief pre-test counseling message and made a routine component of prenatal care.

Sexually transmitted disease among women with HIV infection: a missed opportunity for intervention

Women with HIV disease face not only the same barriers to safe sexual and drug use behaviors that placed them at risk for infection but also problems unique to their serostatus. The high incidence of sexually transmitted disease among some subgroups of women with HIV infection, particularly among those who engage in illicit drug use, demands that the scope of their HIV care encompass identification and treatment of both drug addiction and sexually transmitted disease.

Improvement of radiologists' characterization of mammographic masses by using computer-aided diagnosis: an ROC study

PURPOSE

To evaluate the effects of computer-aided diagnosis (CAD) on radiologists' classification of malignant and benign masses seen on mammograms.

MATERIALS AND METHODS

The authors previously developed an automated computer program for estimation of the relative malignancy rating of masses. In the present study, the authors conducted observer performance experiments with receiver operating characteristic (ROC) methodology to evaluate the effects of computer estimates on radiologists' confidence ratings. Six radiologists assessed biopsy-proved masses with and without CAD. Two experiments, one with a single view and the other with two views, were conducted. The classification accuracy was quantified by using the area under the ROC curve, Az.

RESULTS

For the reading of 238 images, the Az value for the computer classifier was 0.92. The radiologists' Az values ranged from 0.79 to 0.92 without CAD and improved to 0.87-0.96 with CAD. For the reading of a subset of 76 paired views, the radiologists' Az values ranged from 0.88 to 0.95 without CAD and improved to 0.93-0.97 with CAD. Improvements in the reading of the two sets of images were statistically significant (P = .022 and .007, respectively). An improved positive predictive value as a function of the false-negative fraction was predicted from the improved ROC curves.

CONCLUSION

CAD may be useful for assisting radiologists in classification of masses and thereby potentially help reduce unnecessary biopsies.

Efficient processing of DNA ends during yeast nonhomologous end joining. Evidence for a DNA polymerase beta (Pol4)-dependent pathway

Repair of DNA double strand breaks by nonhomologous end joining (NHEJ) requires enzymatic processing beyond simple ligation when the terminal bases are damaged or not fully compatible. We transformed yeast with a series of linearized plasmids to examine the role of Pol4 (Pol IV, DNA polymerase beta) in repair at a variety of end configurations. Mutation of POL4 did not impair DNA polymerase-independent religation of fully compatible ends and led to at most a 2-fold reduction in the frequency of joins that require only DNA polymerization. In contrast, the frequency of joins that also required removal of a 5'- or 3'-terminal mismatch was markedly reduced in pol4 (but not rev3, exo1, apn1, or rad1) yeast. In a chromosomal double strand break assay, pol4 mutation conferred a marked increase in sensitivity to HO endonuclease in a rad52 background, due primarily to loss of an NHEJ event that anneals with a 3'-terminal mismatch. The NHEJ activity of Pol4 was dependent on its nucleotidyl transferase function, as well as its unique amino terminus. Paradoxically, in vitro analyses with oligonucleotide substrates demonstrated that although Pol4 fills gaps with displacement of mismatched but not matched 5' termini, it lacks both 5'- and 3'-terminal nuclease activities. Pol4 is thus specifically recruited to perform gap-filling in an NHEJ pathway that must also involve as yet unidentified nucleases.

Predictors and risk-taking consequences of drug use among HIV-infected women

OBJECTIVE

To determine rates of drug use among women with HIV, and to examine associations between drug use, health, risk behavior, and sexually transmitted diseases (STD).

DESIGN

A longitudinal cohort study of 260 women with confirmed HIV-positive serostatus.

METHODS

Each participant contributed a self-report interview, a clinical examination, laboratory testing of cultures for Trichomonas vaginalis, Chlamydia trachomatis, Neisseria gonorrhoeae, and urinalysis for the presence of metabolites of cocaine and opiates. Data were examined on 140 women at 1-year follow-up. Women were defined as drug users if they reported crack, cocaine, or heroin use in the 6 months before the interview or if they had a positive toxicologic test result for cocaine or opiates.

RESULTS

34% of those in the sample were classified as positive for drug use. Drug use was associated with the number of sexual partners, age at first intercourse, prevalence of STDs, and lower quality of life. STDs were present at baseline in 33.7% and 15.5% of drug users and nonusers, respectively. Drug use among this population was also associated at both baseline and follow-up with the likelihood of having a Karnofsky score below 80, and with overall perceived general health.

CONCLUSIONS

Drug users in this cohort were more likely to engage in behaviors that place them at risk for STDs, to have elevated STD prevalence, and to have lower perceived health across several indices. Identification of drug use and treatment for it need to be a central component of HIV care for women.

Sexual, contraceptive, and drug use behaviors of women with HIV and those at high risk for infection: results from the Women's Interagency HIV Study

OBJECTIVE

To document the sexual and contraceptive practices of women with HIV infection or who are at risk for infection.

DESIGN

Data on the baseline behaviors of 561 HIV-negative and 2040 HIV-positive women were collected as part of the Women's Interagency HIV Study (WIHS). WIHS is a multisite, longitudinal study following the natural history of HIV infection among women in the United States.

METHODS

Each participant contributed an interviewer administered, self-report interview including questions on sexual and contraceptive behavior.

RESULTS

Women with HIV were less likely to report heterosexual activity in the previous 6 months (65% HIV-positive, 76% HIV-negative). Among sexually active women, there were no differences in the proportion of those reporting vaginal (97% HIV-positive, 98% HIV-negative) or anal sex (12% HIV-positive, 10% HIV-negative), although women with HIV were less likely to report cunnilingus (41% HIV-positive, 70% HIV-negative) and fellatio (48% HIV-positive, 57% HIV-negative). Of women with HIV, 63% always used condoms during vaginal sex (versus 28% HIV-negative), with lower rates reported during other sexual activities. Crack, cocaine, or injecting drug use, reported by 27% of HIV-positive and 35% of HIV-negative women, was associated with inconsistent condom use, independent of serostatus. HIV-positive women who reported using condoms and another contraception method were less consistent condom users (57% consistent versus 67%).

CONCLUSIONS

The prevalence of sexual risk behavior in this sample suggests that, although women with HIV exhibit lower levels of sexual risk behavior than uninfected women, many have not been successfully reached with regard to implementing safer behaviors. These findings have implications for more widespread and effective behavioral intervention efforts.

A role for FEN-1 in nonhomologous DNA end joining: the order of strand annealing and nucleolytic processing events

Eukaryotic repair of double-strand DNA breaks can occur either by homologous recombination or by nonhomologous DNA end joining (NHEJ). NHEJ relies on Ku70/86, XRCC4, DNA ligase IV, and DNA-dependent protein kinase. NHEJ involves a synapsis step in which the two ends are maintained in proximity, processing steps in which nucleases and polymerases act on the ends, an alignment step in which a few nucleotides of terminal homology guide the ends into preferred alignments, and a ligation step. Some of the steps, such as ligation, rely on a single enzymatic component. However, the processing steps begin and end with a wide array of alternative substrates and products, respectively, and likely involve multiple nucleases and polymerases. Given the alternative pathways that can be catalyzed by the remaining nucleases and polymerases, no one of these processing enzymes is likely to be essential. The only requirement for the processing enzymes, as a collective, is to generate a ligatable configuration, namely a ligatable nick on each strand. Here, we have tested the two major known 5'-specific nucleases of Saccharomyces cerevisiae for involvement in NHEJ. Whereas EXO1 does not appear to be involved to any detectable level, deleting RAD27 (FEN-1 of yeast) leads to a 4.4-fold reduction specifically of those NHEJ events predicted to proceed by means of 5' flap intermediates. Because Rad27/FEN-1 acts specifically at 5' flap structures, these results suggest that the NHEJ alignment step precedes nucleolytic processing steps in a significant fraction of NHEJ events.

Relationship between mammographic screening intervals and size and histology of ductal carcinoma in situ

OBJECTIVE

The objective of this study was to determine how the length of time between mammographic screenings is related to the size, grade, and histology of mammographically detected ductal carcinoma in situ (DCIS).

MATERIALS AND METHODS

We retrospectively reviewed 166 consecutive mammograms of women evaluated for DCIS with (n = 24) and without (n = 142) microinvasion. The size of the DCIS was determined by the maximum diameter as measured on the mammogram. After pathologic analysis, DCIS was classified by histologic architecture, nuclear grade, presence of microinvasion, and presence of multifocality. Four screening intervals were defined: annual (6-17 months), biennial (18-29 months), triennial (> or = 30 months), and first time. Patients were grouped according to screening intervals. The average age of all groups was 55 years.

RESULTS

The annual group (mean size of DCIS, 1.69 cm) had significantly smaller DCIS than did the biennial (mean size, 2.27 cm), triennial (mean size, 3.49 cm), or first time groups (mean size, 3.29 cm) (p = .003). Comedo histology was more frequently observed in patients screened biennially (73.7%) than in those screened annually (46.8%) (p = .05). High-grade nuclear histology was more commonly seen in the biennial (76.3%) than in the annual (48.1%) screening group (p = .008). We found no significant correlation between screening interval and the incidence of microinvasion and multifocality.

CONCLUSION

Small, low-grade noncomedo DCIS was more common in the annual mammographic screening group than in the biennial screening group. A direct relationship was found between DCIS size and length of screening interval: DCIS detected at annual screening was smaller than that found at biennial screening, which in turn was smaller than DCIS revealed at triennial screening. This study provides inferential support for annual screening mammography for DCIS detection and management.

Mammographic appearance of recurrent breast carcinoma in six patients with TRAM flap breast reconstructions

PURPOSE

To determine the mammographic appearance of locally recurrent cancer in patients with breast reconstructions with transverse rectus abdominis musculocutaneous (TRAM) flaps after mastectomy for primary breast cancer.

MATERIALS AND METHODS

The mammograms and records of women treated for breast cancer with mastectomy and TRAM flap reconstruction who developed local recurrences from 1995 to 1997 were reviewed retrospectively. Eight cancers were identified in six women. Five women had palpable abnormalities, and the sixth had cancer detected at screening mammography at another institution. Mean age at recurrence was 48 years.

RESULTS

All eight cancers were visible on mammograms: four masses, two pleomorphic microcalcifications, and two masses with calcifications. Four of the eight were in the upper central portion of the breast. Before reconstruction, the original histologic diagnosis for all cases had been multifocal ductal carcinoma in situ. All recurrences were invasive cancer. Median time from the original diagnosis of breast cancer to diagnosis of recurrence was 42 months. Two of four patients who subsequently underwent axillary node dissection had metastatic disease in the lymph nodes. The single patient who underwent mammographic screening (elsewhere) had negative axillary lymph nodes.

CONCLUSION

The mammographic appearance of recurrent carcinoma in TRAM flap reconstructions is similar to that of primary breast cancer.

Patient satisfaction with screening mammography: online vs off-line interpretation

RATIONALE AND OBJECTIVES

The purpose of this study was to determine patient satisfaction with online and off-line methods of interpreting screening mammograms and to determine those characteristics that most influence patient preferences.

MATERIALS AND METHODS

A survey consisting of 17 questions assessing satisfaction and demographics was distributed to women whose screening mammograms were read in one of two ways at the same facility: (a) the "online" method, in which all additional requested studies are completed and results are immediately communicated, and (b) the "off-line" method, in which mammograms are read in batches the next day, results are communicated at a later time, and patients return for diagnostic studies. To ensure statistical power, at least 174 surveys were collected from each group.

RESULTS

Of 192 women whose mammograms were interpreted online, 188 (97%) responded, and of 247 women whose mammograms were interpreted off-line, 181 (73%) responded. Overall mean satisfaction with the mammographic experience and with the time it took to receive results differed significantly between the two groups (P < .002). Analysis of the subgroup of very satisfied respondents disclosed that 92% of patients in the online group and 59% of patients in the off-line group were very satisfied with their mammography experience. If allowed to choose the method of interpretation, 97% of patients in the online group and 91% of patients in the off-line group would choose online interpretation.

CONCLUSION

Patients preferred online mammographic interpretation of screening studies.