Particulate Exposure at two Arkansas Racinos; Unsafe Environments?

The purpose of this pilot project was to initiate data collection on secondhand smoke (SHS) for two racinos (racetrack casinos) exempted from Arkansas' 2006 Clean Indoor Air Act. Air quality was assessed during regular hours in sites open to the public. All measurements of fine particulates (PM2.5) within both facilities exceeded maximal safe EPA standards for an equivalent 24-hour average exposure. The exemptions as they stand, fail to protect all interested citizens.

A Multipronged Comparative Study of the Ultraviolet Photochemistry of 2-, 3-, and 4-Chlorophenol in the Gas Phase.

The S1((1)ππ*) state of the (dominant) syn-conformer of 2-chlorophenol (2-ClPhOH) in the gas phase has a subpicosecond lifetime, whereas the corresponding S1 states of 3- and 4-ClPhOH have lifetimes that are, respectively, ∼2 and ∼3-orders of magnitude longer. A range of experimental techniques-electronic spectroscopy, ultrafast time-resolved photoion and photoelectron spectroscopies, H Rydberg atom photofragment translational spectroscopy, velocity map imaging, and time-resolved Fourier transform infrared emission spectroscopy-as well as electronic structure calculations (of key regions of the multidimensional ground (S0) state potential energy surface (PES) and selected cuts through the first few excited singlet PESs) have been used in the quest to explain these striking differences in excited state lifetime. The intramolecular O-H···Cl hydrogen bond specific to syn-2-ClPhOH is key. It encourages partial charge transfer and preferential stabilization of the diabatic (1)πσ* potential (relative to that of the (1)ππ* state) upon stretching the C-Cl bond, with the result that initial C-Cl bond extension on the adiabatic S1 PES offers an essentially barrierless internal conversion pathway via regions of conical intersection with the S0 PES. Intramolecular hydrogen bonding is thus seen to facilitate the type of heterolytic dissociation more typically encountered in solution studies.

First measurements of a carbon dioxide plume from an industrial source using a ground based mobile differential absorption lidar.

The emission of carbon dioxide (CO2) from industrial sources is one of the main anthropogenic contributors to the greenhouse effect. Direct remote sensing of CO2 emissions using optical methods offers the potential for the identification and quantification of CO2 emissions. We report the development and demonstration of a ground based mobile differential absorption lidar (DIAL) able to measure the mass emission rate of CO2 in the plume from a power station. To our knowledge DIAL has not previously been successfully applied to the measurement of emission plumes of CO2 from industrial sources. A significant challenge in observing industrial CO2 emission plumes is the ability to discriminate and observe localised concentrations of CO2 above the locally observed background level. The objectives of the study were to modify our existing mobile infrared DIAL system to enable CO2 measurements and to demonstrate the system at a power plant to assess the feasibility of the technique for the identification and quantification of CO2 emissions. The results of this preliminary study showed very good agreement with the expected emissions calculated by the site. The detection limit obtained from the measurements, however, requires further improvement to provide quantification of smaller emitters of CO2, for example for the detection of fugitive emissions. This study has shown that in principle, remote optical sensing technology will have the potential to provide useful direct data on CO2 mass emission rates.

The role of tissue expansion in the management of large congenital pigmented nevi of the forehead in the pediatric patient.

The authors present a cohort of 21 consecutive patients who had congenital pigmented nevi covering 15 to 65 percent of the forehead and adjacent scalp and who were treated at their institution within the last 12 years. All patients were treated with an expansion of the adjacent texture- and color-matched skin as the primary modality of treatment. The median age at presentation was approximately 1 year; mean postoperative follow-up was 4 years. Nevi were classified according to the predominant anatomic areas they occupied (temporal, hemiforehead, and midforehead/central); some of the lesions involved more than one aesthetic subunit. The authors propose the following guidelines: (1) Midforehead nevi are best treated using an expansion of bilateral normal forehead segments and advancement of the flaps medially, with scars placed along the brow and at or posterior to the hairline. (2) Hemiforehead nevi often require serial expansion of the uninvolved half of the forehead to minimize the need for a back-cut to release the advancing flap. (3) Nevi of the supraorbital and temporal forehead are preferentially treated with a transposition of a portion of the expanded normal skin medial to the nevus. (4) When the temporal scalp is minimally involved with nevus, the parietal scalp can be expanded and advanced to create the new hairline. When the temporoparietal scalp is also involved with nevus, a transposition flap (actually a combined advancement and transposition flap because the base of the pedicle moves forward as well) provides the optimal hair direction for the temporal hairline and allows significantly greater movement of the expanded flap, thereby minimizing the need for serial expansion. (5) Once the brow is significantly elevated on either the ipsilateral or contralateral side from the reconstruction, it can only be returned to the preoperative position with the interposition of additional, non-hair-bearing forehead skin. Expansion of the deficient area alone will not reliably lower the brow once a skin deficiency exists. (6) In general, one should always use the largest expander possible beneath the uninvolved forehead skin, occasionally even carrying the expander under the lesion. Expanders are often overexpanded.

Treatment of hostile midline back wounds: an extreme approach.

The basic principles of successful wound closure remain the same: careful preoperative evaluation, removal of underlying nonviable tissue, and well-vascularized soft-tissue coverage. Many complex or "hostile" back wound closures also require stabilization of the spine and a two-layered wound closure. The use of long arteriovenous fistulas with free tissue transfer provides an additional weapon for the treatment of these complex wounds.

Long-term predictable nipple projection following reconstruction.

The creation of the nipple-areola complex is often the final step in the surgical treatment of breast cancer patients, and it consequently has important symbolic and aesthetic implications. Patient expectations and the need for symmetry make nipple projection a crucial aesthetic determinant of nipple reconstruction. We hypothesize that long-term nipple projection and shape can be achieved in a predictable fashion using the modified star dermal fat flap technique. Prospectively, 93 nipples were reconstructed by a single surgeon using a modified star dermal fat flap technique in 44 implant and 49 TRAM flap breast reconstructions. Flap dimensions (base diameter and flap length) were designed according to patient desire or to the base diameter and projection of the opposite breast nipple. A standardized, 3-month postoperative care regimen was observed in all patients. Nipple projection was assessed by the same observer at each follow-up examination. The average length of follow-up was 730 days (745 for TRAM reconstructions and 713 for implants). Consistently, an average of 41 percent of the intraoperative projection remained intact in both groups at final evaluation (SD 12 percent). The total flap length was strongly predictive of intraoperative and long-term projection (r = 0.64 and 0.86, p < 0.0001). Flap lengths ranged from 5.5 to 9.0 cm, and in a linear correlation, resulted in intraoperative projection of 1.0 to 2.1 cm, respectively, and long-term projection of 0.4 to 0.83 cm, respectively. Based on the linear relationship, every 1-cm increase in flap length could be expected to result in a 0.16-cm increase in projection. When controlled for flap length and intraoperative projection, there was no difference between TRAM and implant nipple reconstruction in predicting postoperative nipple projection. Intraoperative planning and execution are critical to achieve predictable nipple shape, size, and projection. The dimensions of the star dermal fat flap can be strategically modified to allow the surgeon predictable projection with a consistent 41-percent preservation of intraoperative nipple projection in both TRAM and implant patients at 2 years.

Optimization of conscious sedation in plastic surgery.

The administration of conscious sedation by the plastic surgeon must be safe, efficient, and consistent. In the proper setting, with trained staff and appropriate backup, conscious sedation can allow optimal patient satisfaction with expedient recovery in addition to cost containment. The highly effective local anesthesia afforded by dilute, high-volume ("tumescent") infiltration extends the use of conscious sedation to cases previously performed under general anesthesia or deep sedation. The purpose of this analysis was to identify variables in conscious sedation that affect traditional outcome parameters in ambulatory surgery, particularly the duration of recovery and adverse events such as nausea and emesis. All perioperative and operative records of 300 consecutive patients having plastic surgical procedures under conscious sedation were carefully reviewed. Patients were ASA class I or II by requisite. Conscious sedation followed a standardized administration protocol, using incremental doses of two agents: midazolam (0.25 to 1 mg) and fentanyl (12.5 to 50 mcg). A subset of patients received preoperative oral sedation. Multivariate statistical analysis was conducted using SPSS 8.0 for Windows (SPSS Inc., Chicago, Ill.). Of the 300 patients, same-day discharge was intended for 281. Eight procedure categories were defined. No anesthetic complications occurred. As expected, recovery time was significantly correlated with the duration and type of procedure (p < 0.001) and the total dosage of both intraoperative sedative agents (p < 0.001). Interestingly, a negative correlation with advancing age existed (p < 0.001), likely reflecting the significantly higher intraoperative sedative dosing in younger patients (p < 0.001). When controlled for the effects of procedure duration and intraoperative sedative dosing, two other variables-use of preoperative oral sedation and postoperative nausea/emesis-significantly lengthened recovery time (p = 0.0001 for each). Fifteen unintended admissions occurred secondary to nausea, prolonged drowsiness, or pain control needs. Conscious sedation is an effective anesthetic choice for routine plastic surgical procedures, many of which would commonly be performed under general anesthesia. In our experience with a carefully structured and controlled conscious sedation protocol, the technique has proven to be safe and effective. This analysis of outcome parameters identified two important and potentially avoidable causes of recovery delay following conscious sedation-oral premedication and nausea/emesis. Nausea and emesis were particularly problematic in that they were responsible for 11 of 15 (73 percent) unintended admissions. Preoperative sedation is valuable in certain circumstances, and its use is not discouraged; however, its benefits must be weighed against its unwanted effects, which can include a prolongation of recovery.

Necrotizing fasciitis in infancy: an uncommon setting and a prognostic disadvantage.

Necrotizing fasciitis is a potentially fatal, progressive soft tissue infection that typically occurs in adults, and only rarely occurs in infants. Although adults in whom necrotizing fasciitis develops are commonly diabetic, malnourished, or otherwise immunocompromised, infants in whom the disease develops are typically healthy and without clear predisposing factors. Herein, however, the authors report the case of an infant with compromised immunity secondary to the manifestations and treatment of panhypopituitarism, in whom postoperative necrotizing fasciitis developed after bilateral inguinal herniorrhaphy. The diagnosis, pathological mechanism, and treatment of necrotizing fasciitis are reviewed and the distinguishing features in infants are highlighted. The combination of a low incidence and very high mortality rate associated with necrotizing fasciitis in this subgroup strengthens the need for hypercritical suspicion. Early diagnosis and the prompt initiation of surgical treatment are the most essential means to improve on the prognosis for necrotizing fasciitis in infants.

Dermatofibrosarcoma protuberans and the Bednar tumor: treatment in the pediatric population.

Dermatofibrosarcoma protuberans (DFSP) is a low-intermediate-grade cutaneous sarcoma that has a marked propensity for local recurrence after excision. The Bednar variant of this tumor is even less common and is distinguished histologically by the dispersal of melanin containing cells in an otherwise typical DFSP. Both are considered to be tumors of the third and forth decades of life, but both DFSP and the Bednar variant have been described in children. Until this report of a congenital Bednar tumor, only the DFSP has also been described in the neonate. The histopathology and surgical management of DFSP and Bednar tumors are outlined with emphasis on reported experience in the pediatric population. The surgical management of these lesions in children is based on numerous series in adults and the limited pediatric experience. The recommended treatment is wide excision with 3-cm margins of visibly uninvolved tissue and inclusion of superficial fascia.

Riedel's thyroiditis: treatment with tamoxifen.

BACKGROUND: Riedel's thyroiditis is an often disabling disease with clinical and histologic similarity to several other fibrous inflammatory disorders. Surgical treatment alone is often unsatisfactory in permanently alleviating airway compression, dysphagia, neck immobility, pain, or chronic fatigue syndrome. Investigation of drugs shown to be of benefit in the treatment of related fibrous disorders in which hormonal factors or inflammatory deregulation appear to be important is indicated. Tamoxifen has not been previously used in the treatment of Riedel's thyroiditis. METHODS: Four patients with clinical and histologic diagnoses of Riedel's thyroiditis were evaluated before and after treatment with tamoxifen. Each had progressive symptomatic disease of 3 to 16 years' duration despite one or more surgical procedures and steroid therapy. Subjective improvement was noted in all cases, and objective changes were confirmed by periodic physical and computed tomographic examinations. RESULTS: Patients have been monitored for 1 to 4 years with subjective improvement in 100% and objective disease regression ranging from 50% to 100% in all patients. One patient had complete regression within 6 months, and another had more than 50% regression within 3 months. All have returned to predisease activity levels. There were no significant side effects of the therapy. CONCLUSIONS: Tamoxifen has proved to be the most effective drug therapy available for managing Riedel's thyroiditis. Our studies suggest that this is unrelated to antiestrogen activity. Tamoxifen's effectiveness may be caused by a mechanism by which it stimulates the release of transforming growth factor-beta, which may inhibit the fibroblastic proliferation characteristic of Riedel's thyroiditis.

Diagnostic advances in APUDomas and other endocrine tumors: imaging and localization.

The different diagnostic imaging modalities available for determining the location of the various APUDomas are discussed with reference to their advantages and disadvantages. The ability to image these lesions, and to be confident in their role in the underlying pathophysiology, and clinical neuroendocrine syndrome causing symptomatology and illness, has proved to be the key to successful treatment. In many instances it is not the diagnosis that is in question, but it is the extent of disease, the location of the lesion, or whether the anatomical abnormality under study is responsible for the complicating symptoms being considered, that are the crucial questions. The ability to locate APUDomas by a variety of direct and indirect imaging or regionalizing modalities, represent a magnificent advance in the management of these tumors. It should, however, be kept in mind that no one modality or diagnostic method can uniformly be relied upon. It is evident that a multimodal, interactive medical team approach is essential to the successful overall management of patients afflicted with these fascinating tumors.

Investigation of the salivary 18-hydroxycorticosterone:aldosterone ratio in man using a direct assay.

A method for the direct determination of 18-hydroxycorticosterone (18OHB) in human saliva has been developed and validated. Saliva was collected at 30 min and 1 h intervals between 0600 and 2200 h from healthy men and women for the determination of 18OHB (SHB), aldosterone (SA) and glucocorticoids (SGC = cortisol + cortisone). SHB was highly correlated with SA (r = 0.75; P less than 0.001) but even more highly with SGC (r = 0.89; P greater than 0.001). Multiple regression analysis confirmed that SGC was a more important determinant of SHB than was SA. Though the concentrations of 18OHB and aldosterone were highly correlated there was considerable variation in the 18OHB:aldosterone ratio during the period of saliva collection. This ratio tended to be highest in the morning and lowest in the evening and was weakly correlated with SGC level (r = 0.62; P less than 0.01). The 18OHB:aldosterone ratio in saliva approximates to, and is highly correlated with, that in plasma. We suggest that the fluctuations in SHB:SA ratio correspond to the relative rates of secretion of 18OHB and aldosterone and that this ratio is modulated either by ACTH or by cortisol. Whether this indicates that 18OHB is a by-product of glucocorticoid as well as aldosterone metabolism, or whether this implies a separate physiological role for the steroid remains to be clarified.

Time-course and relationship of the early changes in renal sodium excretion and aldosterone secretion during dietary sodium restriction in normal man.

1. The fall in renal sodium excretion after dietary sodium restriction is prompt and reproducible. The importance of increased aldosterone secretion during the early phase (within 48 h) of this response is unclear. Using two indirect measures of aldosterone secretion (in urine and saliva), we have tried to relate changes in excretion and concentration of this hormone to renal sodium excretion during the abrupt transition from a normal (approximately 150 mmol/day) or high (260 mmol/day) to a low (5-25 mmol/day) sodium intake in 11 and seven male volunteers, respectively. 2. All subjects showed reduced renal sodium excretion within 36 h of dietary restriction, but the times at which increases in renal aldosterone excretion, saliva aldosterone concentration and plasma renin activity became statistically significant varied widely (8-72 h, 2.5- greater than 62.5 h and less than 4- greater than 38 h for renal aldosterone secretion, saliva aldosterone concentration and plasma renin activity, respectively). Circadian fluctuations in saliva aldosterone concentration were apparent and increased in amplitude during sodium restriction. 3. Urine flow rate tended to increase on the first day of sodium restriction and this reached statistical significance in the group initially on a high sodium intake (64.0 +/- 8.8 to 84.3 +/- 11.2 ml/h, P less than 0.01); although the pattern of urine flow did correlate with plasma arginine vasopressin concentration (r = -0.49, P less than 0.01), there was no significant decrease in mean plasma arginine vasopressin concentration [1.15 (0.92-1.44) to 0.90 (0.72-1.12) pmol/l, P = 0.08; geometric mean and 95% confidence limits].(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of high altitude on saliva aldosterone and glucocorticoid concentrations.

Saliva was collected from six healthy young men at hourly intervals at sea level and after 1-2, 8-9 and 15-16 days at 4450 m on Mount Kenya for measurement of aldosterone (SA) and glucocorticoid (SGC, cortisol + cortisone) concentrations. Blood samples were collected simultaneously with some of the saliva samples and analysis of these showed that plasma and saliva concentrations of aldosterone and glucocorticoids were highly correlated (r = 0.91 and 0.75 respectively; p less than 0.01 for both hormones). Mean SA for the group was reduced to approximately 50% of the sea-level value (p less than 0.05) by the time the first saliva samples were collected at altitude, and remained at this depressed level throughout the 2-week period on Mount Kenya, although there was considerable inter-subject variation. SGC concentration also tended to be lower on Mount Kenya than at sea level. Though SA was lower throughout the day at altitude compared to sea level, the principal difference in the temporal pattern of SA was the reduction or complete absence of the marked rise in SA that normally occurs in the first few hours after rising. SA and SGC responses to exercise, which consisted of stepping on and off and 0.4-m high stool 60 times/min for 25 min, were assessed at sea level and after various periods at 4450 m.(ABSTRACT TRUNCATED AT 250 WORDS)

Aldosterone is secreted intermittently during pregnancy.

Saliva aldosterone concentration was measured in samples collected at hourly intervals from healthy pregnant women (approximately 26 and 36 weeks gestation) who were going about their normal daily activities, and from some women hospitalized for disorders of pregnancy. In the healthy women diurnal saliva aldosterone fluctuated considerably, the highest values being 2-22 times the lowest on a given day. Because of the known correlation between saliva and plasma aldosterone concentrations we believe that the fluctuating salivary level is indicative of fluctuating plasma levels and that this is due to the intermittent secretion of aldosterone. The rate of decline of saliva aldosterone from peak levels indicated a half life (t 1/2) of 72 (SD 31) min which was not significantly different from that in non-pregnant subjects. The temporal pattern of saliva aldosterone suggests an enhanced response of the zona glomerulosa to the factors that cause aldosterone secretion to fluctuate in non-pregnant subjects, rather than the development of a more potent stimulus to the zona glomerulosa during pregnancy. In addition to hour-to-hour variation there is also substantial day-to-day variation, so that estimation of aldosterone in a single sample of saliva or plasma is of little value during pregnancy. The mean diurnal aldosterone concentration can be estimated from five saliva samples so this measurement presents a convenient technique for the assessment of aldosterone status in pregnancy. In contrast to healthy pregnancy, a patient with pre-eclampsia at 39 weeks gestation showed no elevation of saliva aldosterone above non-pregnant levels at any time during the day.

The determination of 18-hydroxycorticosterone in saliva and plasma: comparison with aldosterone and glucocorticoids.

A radioimmunoassay (RIA) for 18-hydroxycorticosterone (18OHB) is described using antibodies raised against 18OHB-3-CMO conjugated to bovine albumen and an iodine-125 labelled ligand. Extracts of plasma and saliva required thin-layer chromatographic purification prior to RIA. These assays have been validated in terms of precision, accuracy and specificity. The concentration of 18OHB in saliva is approx 20% of that in plasma and the two values are correlated. Thus, in a series of 20 healthy subjects the saliva and plasma concentration were 169 +/- 92 and 904 +/- 621 pmol.l-1 respectively with r = 0.72 (P less than 0.001). When the diurnal patterns of 18OHB, aldosterone and glucocorticoid (cortisol + cortisone) concentrations in saliva were investigated the patterns of 18OHB and aldosterone were usually similar though the 18OHB:aldosterone ratio can vary considerably. These and similar data suggest that the secretion of 18OHB and aldosterone are not completely synchronous. Our results show that saliva is a suitable body fluid in which to estimate 18OHB concentration and this measurement gives a useful reflection of the plasma 18OHB concentration. This technique should facilitate the investigation of the physiological role of this compound.

The effect of cortisol or ACTH on plasma concentrations of free fatty acids.

The effect of infusion of cortisol (14 mumol) or ACTH (Synacthen, 250 micrograms) injection on plasma levels of free fatty acids has been examined in normal men. The increment in plasma cortisol levels after infusion of cortisol (+182%) was much less than after ACTH injection (up to 262%). Mean plasma levels of free fatty acids were only significantly increased after ACTH injection. However, some inter-subject variation occurred and a small but significant increment in plasma levels of free fatty acids was seen for one control subject and for a subject who received an infusion of cortisol. It is possible that the reported diurnal variations in plasma levels of free fatty acids may be related to changes in plasma levels of ACTH or cortisol throughout a 24h period.

Diurnal fluctuation in saliva aldosterone concentration.

We have measured saliva aldosterone concentration (SA) at frequent intervals in subjects going about their normal daytime activities. Four hourly sampling sufficed to give a reasonable estimate of mean diurnal SA but hourly sampling is necessary if it is desired to study the temporal pattern of SA. In subjects with normal or elevated mean levels, SA fluctuated considerably suggestive of several distinct episodes of aldosterone secretion. Such fluctuations show little correlation with the concentrations in saliva of glucocorticoids (cortisol + cortisone) nor are they consistent with a circadian rhythm of aldosterone secretion. We suggest that they may represent responses to such stimuli as eating, drinking or physical activity, and possibly to other as yet unidentified factors. These observations show the importance of comprehensive diurnal assessment of aldosterone level in physiological and pathological investigations. Because of its non-invasive nature and the high productivity of the assay, measurement of SA is ideally suited for this purpose.