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Racial differences in pelvic morphology among asymptomatic nulliparous women as seen on three-dimensional magnetic resonance images.

OBJECTIVE: Compare pelvic morphology between asymptomatic African-American and white nulliparous women. STUDY DESIGN: Resting supine T2-weighted magnetic resonance (MR) images were obtained in 12 African-American (AA) and 10 white American (WA) women without pelvic floor dysfunction. Three-dimensional models were reconstructed from the MR images by a masked investigator, and predefined bony and soft tissue pelvic floor parameters were measured and compared. Nonparametric statistics were used, with significance considered at P < .05. RESULTS: Subjects were similar in age and body mass index. Levator ani volume was significantly greater in the AA versus the WA group (mean = 26.8 vs 19.8 cm3, P = .002). The levator-symphysis gap was smaller in the AA (left-18.2, right-18.8 mm) versus the WA group (22.4, 22.6 mm, P = .003, .048) on the left and right. Significant differences were seen in bladder neck position, urethral angle, and the pubic arch angle. CONCLUSION: The increased muscle bulk and closer puborectalis attachment seen among the African-American nulliparous women may impact the development of pelvic floor dysfunction. These findings need further study.

Adult↗

Shift length and on-duty rest patterns in rotor-wing air medical programs.

INTRODUCTION: Air medical teams provide around-the-clock critical care, a pattern at risk of inducing performance-altering fatigue from circadian disruption and sleep deprivation. Safety is an essential issue in the air medical industry, but little data are available on shift length and on-duty rest practices. We report the results of a survey concerning those practices and analyze the relationships to crew duty practices by program model (hospital-operated, vendor-operated, independent, or public safety), base location, flight volume, and job requirements. METHODS: A survey was mailed to 182 Association of Air Medical Services-member rotor-wing air medical programs in the United States that complete scene flights with a flight nurse. One-hundred-twenty-nine programs (70.9%) returned anonymous surveys, all of which were used for data analysis. Results were analyzed with descriptive and nonparametric statistics. RESULTS: All pilots work shifts between 10 and 14 hours. For medical team members the shift distribution is: </= 8 hours, 0.4%; 9 to 12 hours, 44.2%; 12 to 16 hours, 7.0%; 17 to 24 hours, 45%; > 24 hours, 3.5%. An independent association exists between shift length greater than 12 hours and each of the following: flight volume per-aircraft under 731 flights/year, program model other than hospital operated, and nonhospital base (Fisher's exact test with Bonferroni correction, P < .01 for each). All pilots are allowed on-duty rest on both day and night shifts. On-duty rest is permitted for 67.4% of medical team members: 18.2% only at night, and 49.2% at any time of day. The presence of any period of on-duty crew rest is significantly associated with nonhospital base, program model other than hospital-operated, and shift length exceeding 12 hours (Fisher's exact test with Bonferroni correction, P < .01 for each). The presence of a nonflight clinical assignment while on flight duty is associated with a prohibition against on-duty rest (Fisher's exact test with Bonferroni correction, P < .05). CONCLUSION: Notable differences arose between on-duty work and rest patterns for pilots and medical team members. Medical team members generally work longer shifts than pilots do, with shifts exceeding 12 hours as the most common staffing pattern. Medical team members also have less access to on-duty rest than do pilots. Traditional hospital-operated programs are more likely to use shorter shifts and prohibit on-duty rest for the medical teams, whereas vendor-operated, independent, or public safety programs are more likely to use longer shifts and permit on-duty rest. As the industry works toward a unified approach to mitigating the impact of fatigue on safe operation, variable practices based on job description and program style may be a factor.

Air Ambulances↗

Treatment and outcome of patients with chest wall recurrence after mastectomy and breast reconstruction.

BACKGROUND: Chest wall recurrence (CWR) in the setting of previous mastectomy and breast reconstruction can pose complex management dilemmas for clinicians. We examined the impact of breast reconstruction on the treatment and outcomes of patients who subsequently developed a CWR. METHODS: Between 1988 and 1998, 155 breast cancer patients with CWR after mastectomy were evaluated at our center. Of these patients, 27 had previously undergone breast reconstruction (immediate in 20; delayed in 7). Clinicopathologic features, treatment decisions, and outcomes were compared between the patients with and without previous breast reconstruction. Nonparametric statistics were used to analyse the data. RESULTS: There were no significant differences between the reconstruction and no-reconstruction groups in time to CWR, size of the CWR, number of nodules, ulceration, erythema, and association of CWR with nodal metastases. In patients with previous breast reconstruction, surgical resection of the CWR and repair of the resulting defect tended to be more complex and was more likely to require chest wall reconstruction by the plastic surgery team rather than simple excision or resection with primary closure (26% [7 of 27] versus 8% [10 of 128], P = 0.013). Risk of a second CWR, risk of distant metastases, median overall survival after CWR, and distant-metastasis-free survival after CWR did not differ significantly between patients with and without previous breast reconstruction. CONCLUSIONS: Breast reconstruction after mastectomy does not influence the clinical presentation or prognosis of women who subsequently develop a CWR. Collaboration with a plastic surgery team may be beneficial in the surgical management of these patients.

Adult↗

Dermatologic conditions associated with use of a lower-extremity prosthesis.

OBJECTIVES: To document the frequency of skin problems among lower-limb prosthesis users and to assess for factors associated with skin problems among patients using a prosthesis. DESIGN: Six-year retrospective chart review. SETTING: An outpatient amputee clinic at a regional, referral rehabilitation hospital in Canada. PARTICIPANTS: Seven hundred forty-five subjects with a total of 828 lower-extremity amputations participated. Subjects were included if they had a lower-extremity amputation and used a prosthesis for ambulation or transfers. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The presence or absence of a skin problem. Descriptive and nonparametric statistics were used to analyze data. RESULTS: Three hundred thirty-seven residual limbs (40.7%) had at least 1 skin problem. Adjusted odds ratios showed that amputation level, being employed, type of walking aid, and absence of peripheral vascular disease (as a comorbidity) were independently associated with the presence of at least 1 skin problem ( P <.05). CONCLUSIONS; Dermatologic conditions are a frequent complication for the lower-extremity amputee who uses a prosthesis. The results suggest that more active amputees have an increased risk for developing skin problems. Further study in this area is warranted.

Aged↗

Evaluation of novel sample identification approach based on chromatographic fingerprint set correlation homogeneity analysis.

Instead of usual rationale for chromatographic fingerprint based sample identification which relies upon visual inspection or principal component analysis of raw or aligned chromatograms novel nonparametric statistical measure of fingerprint set homogeneity is proposed. Randomization test is applied for significance analysis of fingerprint set homogeneity while average maximum crosscorrelation is used as a merit function. Chromatogram sets generated by random selection from standard and unknown sample chromatogram collections are compared with respect to merit function values with set of chromatograms that represents standard and/or unknown sample. In that instance fingerprint homogeneity significance is represented by the fraction of random chromatogram sets that have higher merit values than the standard and/or unknown sample sets. A set of peptide maps corresponding to different haemoglobin variants has been selected for evaluation of proposed test. This approach is compared to chromatogram alignment based on correlation optimized warping coupled with principal component or cluster analysis. Proposed method is simple i.e. straightforward sample identification procedure which reliability has been evaluated here. Impact of this approach on peptide mapping validation and system suitability analysis is discussed.

Chromatography, Liquid↗

Restrained cerebral hyperperfusion in response to superimposed acute hypoxemia in growth-restricted human fetuses with established brain-sparing blood flow.

OBJECTIVE: To investigate the cerebral circulatory response to superimposed acute hypoxemia in growth-restricted fetuses with established brain-sparing flow (BSF) during basal conditions. MATERIAL AND METHODS: 76 term fetuses suspected of growth restriction were exposed to Doppler velocimetry in the umbilical artery (UA) and middle cerebral artery (MCA), and in 38-39 cases also in Galen's vein (GV), straight sinus (SS), and transverse sinus (TS), before and during an oxytocin challenge test (OCT), and simultaneous to electronic fetal heart rate monitoring. Nonparametric statistical analyses compared presence/absence of established BSF (MCA-to-UA pulsatility index [PI] ratio <1.08) with a two-tailed P<0.05 considered significant. RESULTS: The OCT (positive/negative) was not different in the BSF group (BSFG, N=16) and the normal flow group (NFG, N=60) (P=0.2). During uterine contractions, the MCA PI decreased in the NFG, but not in the BSFG. De novo GV pulsations and increase of GV maximum flow velocity occurred during contractions in the NFG, but not in the BSFG. Significant SS flow velocity waveform changes were found in neither group and TS flow changes in the BSFG only. CONCLUSIONS: Fetuses without established brain-sparing flow during basal conditions responded with both arterial and venous brain-sparing flow during acute hypoxemia, whereas in fetuses with established brain-sparing flow the cerebral circulatory responses were absent or equivocal. Fetuses with established brain-sparing flow may have a limited capacity of further cerebral hyperperfusion during superimposed acute hypoxic stress.

Cerebrovascular Circulation↗

Acute centralization of blood flow in compromised human fetuses evoked by uterine contractions.

BACKGROUND: During fetal hypoxia blood is redistributed to the brain ('brain-sparing'). Sequential changes of the cerebral and placental circulation in parallel in comparisons between basal conditions and acute hypoxic stress have not yet been thoroughly studied in human fetuses. AIM: To explore acute fetal middle cerebral artery (MCA) circulatory changes relative to umbilical artery (UA) blood flow in a clinical experimental model with hypoxic stress provoked by uterine contractions during an oxytocin challenge test (OCT). STUDY DESIGN: Prospective comparative between imminently compromised (OCT positive) and un-compromised (OCT negative) fetuses. SUBJECTS AND METHODS: 82 term pregnancies suspected of intrauterine growth restriction were exposed to simultaneous electronic fetal heart rate monitoring and Doppler recordings of pulsatility index (PI) in the UA and MCA during basal conditions and during uterine contractions and relaxations at an OCT. OUTCOME MEASURES: Sequential changes of UA and MCA PI, OCT positive vs. negative cases. Nonparametric statistics with a P < 0.05 considered significant. RESULTS: The UA PI was significantly higher in OCT positive cases (N = 10) compared with OCT negative cases (N = 72) during uterine contractions and relaxations, but not during basal measurements. During contractions and relaxations the MCA PI decreased significantly in both groups (brain-sparing), but significantly more in OCT positive cases. CONCLUSIONS: During acute hypoxic stress, changes towards a centralization of blood flow to the brain develop in imminently compromised (OCT positive) fetuses at an expense of the umbilicoplacental blood flow, and the brain-sparing flow is more pronounced than in un-compromised (OCT negative) fetuses.

Birth Weight↗

Two-year follow-up of quality of life in patients referred for heart transplant.

BACKGROUND: Assessment of physical and mental health has become one of the ultimate tests of health-related quality of life (HRQOL) for patients with advanced heart failure. Little is known, however, about the comparative effects of surgical or medical treatment on the HRQOL of these chronically ill patients over time. METHODS: We examined 77 patients (74% of whom were male), aged 56.1 +/- 12.7 years who were referred for heart transplant evaluation at a single heart failure center to describe the effects of time and treatment status on changes in HRQOL scores (physical and mental health and depression) using the Short Form-12 and the Beck Depression Inventory at 2 time points during their illness trajectory. The 2 evaluations on average were 2 years apart (mean 24.5 +/- 2.8 months). All patients were evaluated at baseline, and 3 groups were identified at the time of the 2-year follow-up: transplant recipients (n = 17), transplant candidates (n = 13), and medically stable patients considered too well to receive a transplant (n = 47). Nonparametric statistics were used to analyze group differences in HRQOL scores. The significance level was set at a P value less than .05. RESULTS: Demographic and HRQOL scores were not significantly different among the 3 groups at baseline. During follow-up, physical health and depression scores significantly improved over time in all patients, but changes in mental health were minimal. Group comparisons showed that although all patients continued to have low HRQOL scores at the time of follow-up evaluation, medically stable patients had higher mental health scores and less depressive symptoms than their counterparts. CONCLUSION: Our results support the need for ongoing HRQOL assessment with an emphasis on timely recognition and treatment of psychologic distress throughout the heart failure illness trajectory. Heart transplant recipients and candidates equally need special attention and follow-up because they both seem to have emotional and psychologic repercussions.

Adult↗

Family perceptions of nurses' roles toward family members of critically ill patients: a descriptive study.

OBJECTIVES: The purpose of this study was to examine the role of the nurse with families of critically ill patients as perceived by family members and whether meeting family expectations impact family satisfaction. METHODS: A descriptive design was conducted with 29 family members from a 19-bed intensive care unit. Nonparametric statistics, known for their appropriateness for small samples, were used to examine the research questions. RESULTS: Overall, the expectations that family members held regarding nurses' roles with families were not different from their perceptions of what nurses actually did (P = .087). Family members were more satisfied with care when nurses' performance either met or exceeded their expectations (P = .046). CONCLUSION: Nurses did well with regard to meeting family members' expectations. Variations in expectations among family members reflect their diversity and highlight the importance of assessing family needs on a case-by-case basis.

Adult↗

Evaluation of the vibratory feeder method for assessment of powder flow properties.

The flow properties of pharmaceutical powders and blends used in solid oral dosage forms are an important consideration during dosage form development. The vibratory feeder method, a flow measurement technique that quantifies avalanche flow, has been adapted for measurement of the flow properties of common pharmaceutical powders used in solid oral dosage forms. The flow properties of 17 different powders were measured with the instrument, and the results are reported as a powder flow index (PFI). The PFI trends of the powders correlate well with flow properties reported in the literature. The flow properties of the powders were also measured with a commercially available avalanche instrument, the Aero-Flow, and the results were reported as the mean time to avalanche (MTA). Since the two instruments analyze the avalanche by different algorithms, the results were compared with nonparametric statistical evaluation of ranked data, and they were found to be in excellent agreement. A recommended procedure for measurement of powder flow with the vibratory feeder is presented.

Powders↗

A school-based intervention to promote dietary change.

PURPOSE: This study examined the effect of 2 school-based interventions on adolescents' consumption and knowledge of fish with the hypothesis that home economics education would enhance the effect of modifications in the school canteen. The school lunch intervention (SL) focused on changes in the school canteen, and the school lunch + home economics intervention (SL + HE) in addition consisted of changes in the home economics syllabus. Pupils in the 8th grade (n = 228) from 3 schools in Göteborg, Sweden, participated (control, n = 83; SL group, n = 58; SL + HE group, n = 87). METHODS: A controlled design was used in which behavior and knowledge were assessed before and after the intervention. In contrast to much previous research of this type, measurement of behavior was based primarily on direct observation as opposed to self-reported intakes. Behavior (fish consumption) was measured individually by structured observations in the school canteen 5 times (once a week) when fish was served. Nutritional knowledge was measured by means of 10 items in a questionnaire. To analyze changes in behavior, a nonparametric statistical method assessing systematic change in paired ordered categoric variables was used. RESULTS: At follow-up evaluation, consumption had increased significantly in the SL + HE group, a change that also differed from the control group. In addition, significant positive changes in knowledge were observed in both intervention groups, but not in controls. CONCLUSIONS: The results suggest that dietary change was achieved by modifying conditions in the school canteen together with changing the home economics syllabus. This study shows the importance of the school in the promotion of dietary change among adolescents.

Adolescent↗

A pilot study comparing two manual therapy interventions for carpal tunnel syndrome.

OBJECTIVE: The purpose of this study was to determine the clinical efficacy of manual therapy interventions for relieving the signs and symptoms of carpal tunnel syndrome (CTS) by comparing 2 forms of manual therapy techniques: Graston Instrument-assisted soft tissue mobilization (GISTM) and STM administered with the clinician hands. METHODS: The study was a prospective comparative research design in the setting of a research laboratory. Volunteers were recruited with symptoms suggestive of CTS based upon a phone interview and confirmed by electrodiagnostic study findings, symptom characteristics, and physical examination findings during an initial screening visit. Eligible patients with CTS were randomly allocated to receive either GISTM or STM. Interventions were, on average, twice a week for 4 weeks and once a week for 2 additional weeks. Outcome measures included (1) sensory and motor nerve conduction evaluations of the median nerve; (2) subjective pain evaluations of the hand using visual analog scales and Katz hand diagrams; (3) self-reported ratings of symptom severity and functional status; and (4) clinical assessments of sensory and motor functions of the hand via physical examination procedures. Parametric and nonparametric statistics compared treated CTS hand and control hand and between the treatment interventions, across time (baseline, immediate post, and at 3 months' follow-up). RESULTS: After both manual therapy interventions, there were improvements to nerve conduction latencies, wrist strength, and wrist motion. The improvements detected by our subjective evaluations of the signs and symptoms of CTS and patient satisfaction with the treatment outcomes provided additional evidence for the clinical efficacy of these 2 manual therapies for CTS. The improvements were maintained at 3 months for both treatment interventions. Data from the control hand did not change across measurement time points. CONCLUSIONS: Although the clinical improvements were not different between the 2 manual therapy techniques, which were compared prospectively, the data substantiated the clinical efficacy of conservative treatment options for mild to moderate CTS.

Carpal Tunnel Syndrome↗

Increased CXCR3 expression associated with CD3-positive lymphocytes in the liver and biliary remnant in biliary atresia.

BACKGROUND: Lymphocyte-mediated inflammatory damage of the bile ducts has been proposed as a potential mechanism in the pathogenesis of biliary atresia (BA). Chemokines regulate leukocyte migration and act as critical organizers of cell distribution in inflammatory responses. The aim of this study was to analyze the infiltration of T lymphocytes and the expression of a chemokine receptor, CXCR3, predominantly expressed on type 1 polarized T cells (T(H)1, T(C)1) in the liver and excised biliary remnants in infants with BA. METHODS: Immunohistochemistry for CD3, CD8, and CXCR3 was performed using liver biopsy specimens collected from the following 3 age-matched groups of patients: group 1, BA (nonsyndromic) at the time of Kasai portoenterostomy (n = 10); group 2, congenital choledochal dilatation (n = 2); and group 3, other cholestatic diseases including paucity of intrahepatic bile ducts and cholestasis (n = 3) related to total parenteral nutrition. Cellular staining on each section was graded from 0 to 4 and compared using nonparametric statistics. RESULTS: Infiltrating CD3+ and CD8+ lymphocytes in the portal tracts were significantly increased in group 1 (3.1 +/- 0.4, 2.8 +/- 0.4), compared with groups 2 (1.0 +/- 0.0, 1.0 +/- 0.0) and 3 (1.7 +/- 0.3, 1.5 +/- 0.5) (P < .01, P < .05). CXCR3+ mononuclear cells were significantly increased in group 1 (2.6 +/- 0.3) compared with groups 2 (0.5 +/- 0.5) and 3 (0.7 +/- 0.3) (P < .05). They were mainly found in the portal tracts with a similar distribution to CD3+ cells. CXCR3+ cells and CD3+ cells also showed a similar distribution in specimens of biliary remnants from just below the portal plate. CONCLUSIONS: Increased expression of CXCR3 associated with a significantly increased CD3 and CD8 T-cell infiltration suggests that CXCR3+ lymphocytes in a type 1 (T(H)1, T(C)1) cytokine milieu may play a role in the pathogenesis of BA.

Bile Ducts↗

Extracellular matrix dynamics associated with tissue-engineered intravascular sclerotherapy.

BACKGROUND: The extracellular dynamics after intravascular sclerotherapy with an injectable, fibroblast-based engineered construct is unknown. METHODS: Rabbits underwent ethanol sclerotherapy of a jugular vein segment. Control animals (n = 40) underwent no further treatment or an acellular collagen hydrogel was injected. Experimental animals (n = 20) received a tissue-engineered construct. After 1, 2, 4, and 20 to 24 weeks, segments were evaluated for collagen, glycosaminoglycan (GAG), matrix metalloproteinase (MMP) 2 and 9, and tissue inhibitors of MMP (TIMPs) 1 and 2 and scored on a scale of 0 to 3. Groups and time points were compared using nonparametric statistical analysis. RESULTS: Collagen content was higher in animals that received fibroblasts (P < .05). Glycosaminoglycan analysis showed a higher grade only at 1 week (P < .05). Collagen and GAG deposition were prominent at weeks 1 through 4, and decreased over time. Both MMP-2 and MMP-9 and TIMP-1 and TIMP-2 grade decreased with time (P < .01) in all groups, with no differences between groups. CONCLUSION: Enhancement of intravascular sclerotherapy by tissue engineering stems, at least in part, from increased local deposition of collagen and GAG. MMP and TIMPs may play a role in recanalization after experimental sclerotherapy. Tissue engineering may be a valuable adjunct for the treatment of vascular malformations.

Animals↗

Hemodynamic and clinical impact of ultrasound-derived venous reflux parameters.

PURPOSE: This study was undertaken to assess which ultrasound-derived parameter was superior for measuring venous reflux quantitatively and to evaluate the importance of popliteal vein valve reflux. PATIENTS AND METHODS: A retrospective analysis was performed of 244 refluxive limbs in 182 patients who underwent ultrasound scanning, venous pressure measurement, air plethysmography, and clinical classification of severity according to the CEAP score. Reflux time (RT, s), peak reflux velocity (PRV, m/s), time of average rate of reflux (TAF, mL/min), absolute displaced volume retrogradely (ADV, mL) were compared to clinical class, ambulatory venous pressure (% drop), venous filling time (s), and venous filling index (mL/s) using nonparametric statistical tests. A P value of <.05 was considered significant. Limbs were divided into 3 groups: (A) axial great saphenous vein reflux only (n = 68); (B) axial deep reflux including popliteal vein incompetence with or without concomitant gastrocnemius or great or small saphenous vein reflux (all ultrasound reflux parameters of each refluxive vein added at the knee level) (n = 79); and (C) all limbs with popliteal vein reflux (the ultrasound data of the refluxive popliteal vein exclusively was used in comparison regardless of concomitant associated reflux) (n = 103). Limbs were also stratified into limbs with skin changes and ulcer (C-class 4-6) and those without (C-class 1-3) and subsequently compared. RESULTS: No meaningful significant correlation was found between RT and the clinical and hemodynamic results in groups A and B. The PRV and TAF correlated significantly with the hemodynamic parameters. The PRV and TAF and clinical severity trended towards correlation in group A (P =.0554 and P =.0998, respectively), but was significantly correlated in group B. The poor hemodynamic condition in the subset of C-class 4-6 limbs in groups A and B was reflected in a greater PRV, TAF, and ADV in this subset as compared with the limbs in C-class 1-3. RT was not significantly different in the subsets of limbs, further suggesting that RT is not related to hemodynamic or clinical state of the limbs. No meaningful correlations were found in group C. Although the hemodynamic data were significantly poorer in the subset of limbs with C-class 4-6 than in C-class 1-3, the ultrasound-derived parameters were not significantly different. CONCLUSION: The duration of valve reflux time (or valve closure time) cannot be used to quantify severity of reflux and is purely a qualitative measurement. The PRV and the rate of reflux appeared to better reflect the magnitude of venous incompetence. In the presence of axial reflux, it appeared logical and physiologically correct to sum up these reflux parameters for each venous segment crossing the knee. The popliteal valve reflux (the "gatekeeper" function) was not in itself an important determinant of venous hemodynamics and clinical severity. Additional reflux in other venous segments must be taken into account.

Adolescent↗

Empirical comparison of maximal voxel and non-isotropic adjusted cluster extent results in a voxel-based morphometry study of comorbid learning disability with schizophrenia.

We present an empirical comparison of cluster extent and maximal voxel results in a voxel-based morphometry (VBM) study of brain structure. The cluster extents are adjusted for underlying deviation from uniform smoothness. We implement this comparison on a four-group cohort that has previously shown evidence of a neuro-developmental component in schizophrenia (Moorhead, T.W.J., Job, D.E., Whalley, H.C., Sanderson, T.L., Johnstone, E.C. and Lawrie, S.M. 2004. Voxel-based morphometry of comorbid schizophrenia and learning disability: analyses in normalized and native spaces using parametric and nonparametric statistical methods. NeuroImage 22: 188-202.). We find that adjusted cluster extent results provide information on the nature of deficits that occur in the schizophrenia affected groups, and these important structural differences are not all shown in maximal voxel results. The maximal voxel and cluster extent results are corrected for multiple comparisons using Random Fields (RF) methods. In order to apply the cluster extent measures, we propose a post-hoc method for determining the primary threshold in the analysis. Unadjusted cluster extent results are reported, for these, no allowance is made for non-isotropic smoothness, and comparison with the adjusted extent results shows that the unadjusted results can be either conservative or anti-conservative depending upon the underlying tissue distributions.

Cluster Analysis↗

Asthma and allergy in alpha-1 antitrypsin deficiency.

This study was designed to determine the prevalence of asthma and atopy, in a large group of subjects with alpha-1 antitrypsin deficiency (AATD) participating in the Alpha-1 Foundation Research Registry. A survey was mailed to all Registry participants (N=2418) and results were collated by AATD phenotype. Participants with PiZZ deficiency were compared to PiMZ and other phenotypes by nonparametric statistics. Responses were collected from 757 participants (31%). Overall 44.6% (N=338) reported MD diagnosed asthma. Wheezing was reported in 76% with respiratory infections, activity and exposure to dusts, fumes, and allergens as common triggers. Across the three groups reported asthma with a history of allergies was reported from 20% to 25%. Wheezing symptoms were significantly less common in the PiMZ group compared with other groups. Of those reporting asthma, 83% of the PiZZ group (n=192) also reported another chronic obstructive pulmonary disease (COPD) diagnosis compared to 48% of the PiMZ group (n=24). Asthma as the only reported diagnosis was three times more prevalent in the PiMZ group compared with the PiZZ group. Although asthma diagnosis is imprecise in the presence of COPD, the high prevalence of wheezing to allergen and irritant exposures with symptoms of atopy suggests that asthma is common in AATD but usually associated with COPD. Those with AATD who are susceptible to asthma require allergy evaluation and aggressive anti-inflammatory strategies as part of their management.

Adult↗

A cross-study meta-analysis and three-dimensional comparison of cell counting in the anterior cingulate cortex of schizophrenic and bipolar brain.

Using a two-dimensional cell counting approach, a 1991 study in the anterior cingulate cortex (ACCx) detected a reduction in the density of nonpyramidal neurons in layers II-VI of schizophrenic subjects. Schizophrenics without superimposed mood disturbances showed a 16% decrease in layer II, while schizoaffectives showed a 30% decrease, suggesting that a decreased density of nonpyramidal neurons in layer II of ACCx might vary more strongly with affective disorder than with schizophrenia. Two follow-up studies from this laboratory, one a replication of that reported in 1991 and the other an analysis of tyrosine hydroxylase immunoreactive fibers, were undertaken in ACCx of normal controls and schizophrenics. These three data sets have been combined and a meta-analysis of the density of pyramidal, nonpyramidal and glial cells was performed to explore whether changes in the density of interneurons in ACCx may be a reliable finding in the major psychoses. Not all groups have reported this finding, but several had employed a different cell counting technique (i.e. three dimensional optical dissector), which could help to explain the discrepant findings in schizophrenia and affective disorder. The data from each of three different studies (now designated as studies A, B and C, respectively) have been internally normalized, combined into a single dataset and analyzed using nonparametric statistics. Tissue blocks from a subset of cases in study B (six controls, six schizophrenics and six bipolars) were embedded in celloidin and counted using an "unbiased" three dimensional counting method (study D). The data from studies A and B indicate that the density of nonpyramidal neurons in layer II of ACCx in the schizoaffective and bipolar samples was significantly decreased. In the schizophrenics, the nonpyramidal neurons were also decreased, but only by 15%. All three groups also showed a decrease of pyramidal neurons in layers IV, V and VI, but this difference was significant only in layer IV of the schizophrenics. When data from study C were added, the differences in pyramidal and nonpyramidal neurons were less striking. For study D, the pattern of findings are strikingly similar to those obtained in studies A, B and C, indicating that both 2D and 3D cell counting methodologies are capable of detecting the same differences. Taken together, these results indicate that the earlier finding of a decreased density of nonpyramidal neurons in ACCx of schizophrenics is consistent across non-overlapping subjects and/or methods in four separate studies, and is more pronounced in schizoaffective and bipolar subjects than in schizophrenics without superimposed mood disturbance.

Bipolar Disorder↗