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Mitigating the deleterious effects of climate change requires the development and implementation of carbon capture and storage technologies. To expand the monitoring, verification, and reporting (MRV) capabilities of geologic carbon mineralization projects, we developed a thermogravimetric analysis-mass spectrometry (TGA-MS) methodology to enable quantification of <100 ppm calcite (CaCO3) in complex samples. We extended TGA-MS calcite calibration curves to enable a higher measurement resolution and lower limits of quantification for evolved CO2 from a calcite-corundum mixture. We demonstrated <100 ppm carbonate mineral quantification with TGA-MS for the first time, an outcome applicable across earth, environmental, and materials science fields. We applied this carbonate quantification method to a suite of Columbia River Basalt Group (CRBG) well cuttings recovered in 2009 from Pacific Northwest National Laboratory's Wallula #1 Well. Our execution of this new combined calcite and calcite-corundum calibration curve TGA-MS method on our CRBG sample suite indicated average carbonate contents of 0.050 wt % in flow interiors (caprocks) and 0.400 wt % in interflow zones (reservoirs) in the upper 1250 m of the Wallula #1 Well. By advancing our knowledge of continental flood basalt-hosted carbonates in the mafic subsurface and reaching new TGA-MS quantification limits for carbonate minerals, we expand MRV capabilities and support the commercial-scale deployment of carbon mineralization projects in the Pacific Northwest United States and beyond.

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OBJECTIVES: To explore the experiences of congenitally or early profoundly deafened candidates who receive cochlear implants as adults. METHODS: Eight congenitally or early profoundly deafened implantees who had received their implants as adults were interviewed using a semi-structured interview technique. Interviews were conducted in the participant's preferred communication mode (oral/aural, Sign Supported English, or British Sign Language). RESULTS: All participants reported benefit from implantation. Areas of benefit identified correspond with results from similar studies conducted with post-lingually deafened adult implantees. DISCUSSION: Congenitally or early profoundly deafened adults implanted as adults report benefit from cochlear implantation in the following areas: identity, hearing the world, and emotional wellbeing. They also commented on their motivation for wanting an implant and the advice they would give to others considering implantation.

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BACKGROUND: Robotic adrenalectomy is a minimally invasive alternative to traditional laparoscopic adrenalectomy. To date, only case reports and small series of robotic adrenalectomies have been reported. This study presents a single institution's series of 30 robotic adrenalectomies, and evaluates the procedure's safety, efficacy, and cost. METHODS: Thirty patients underwent robotic adrenalectomy at the Johns Hopkins Hospital between April 2001 and January 2004. Patient morbidity, hospital length of stay, operative time, and conversion rate to traditional laparoscopic or open surgery are presented. Improvement in operative time with surgeon experience is evaluated. Hospital charges are compared to charges for traditional laparoscopic and open adrenalectomies performed during the same time period. RESULTS: Median operative time was 185 min. Patient morbidity was 7%. There were no conversions to traditional laparoscopic or open surgery. The median hospital stay was 2 days. Operative time improved significantly by 3 min with each operation. Hospital charges for robotic adrenalectomy (12,977 dollars) were not significantly different than charges for traditional laparoscopic (11,599 dollars) or open adrenalectomy (14,600 dollars). CONCLUSIONS: Robotic adrenalectomy is a safe and effective alternative to traditional laparoscopic adrenalectomy.

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BACKGROUND: We developed a tool, the Surgical Recovery Index (SRI), specifically to measure surgical recovery. We then tested the ability of the SRI to discriminate between patients undergoing laparoscopic (L) operations and patients undergoing open (O) operations. METHODS: We surveyed 50 patients drawn from the practice of a single surgeon to establish the types of activities that define recovery from surgery. Their responses were used to construct the SRI, a self-administered questionnaire using a numerical rank-order scale format. A total score and two subscale scores (pain and activity resumption) were calculated for each patient. Mean and median scores were calculated for each patient group. Chi-square tests were used to evaluate group differences for individual questions; t-tests and Kruskal-Wallis tests were used to evaluate group differences for summary scores. RESULTS: In all, 149 patients completed the SRI (60 L, 89 O). Cronbach's alphas were 0.91 for pain questions and 0.97 for activity resumption questions. The scores for pain level with time (L vs O, 1-10 scale) at week 1 (mean, 4.42 vs 6.06, p = 0.03), week 2 (mean, 3.08 vs 4.38, p = 0.04), week 3 (mean, 2.03 vs 3.16, p = 0.02), and week 4 (mean, 1.18 vs 2.28, p = 0.00) all favored laparoscopy. The scores for pain level with activity (L vs O, 1-3 scale) for getting out of bed (mean, 1.62 vs 1.85, p = 0.04), hygiene activities (mean, 1.38 vs 1.65, p = 0.04), and computer work (mean, 1.15 vs 1.56, p = 0.00) were all significant, although pain with exertion (mean, 1.87 vs 2.10, p = 0.13) was not. Delay until return to activity (L vs O, 1-4 scale) was significant, favoring L for 13 activities (all p < 0.02), but it was not significant for three activities. The scores for subscales for pain (L vs O, mean, 20.7 vs 34.4, respectively) and activity resumption delay (mean, 44.3 vs 62.0), as well as total scores (mean, 33.0 vs 49.0), were also significant (all p = 0.00). The same differences were observed when median scores were considered instead of mean scores, suggesting the robustness of the group difference. CONCLUSIONS: Reduction in time to full recovery (i.e., pain resolution and activity resumption) is a fundamental advantage of laparoscopic surgery, yet there are no tools designed to specifically measure recovery. These data provide preliminary evidence of the reliability and validity of the new SRI as a measure of recovery in patients undergoing laparoscopic operations.

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Intravenous administration of serotonin inhibits the nociceptive tail-flick (TF) reflex, partially through activation of vagal afferents. The present study examined the role of the rostral ventral medulla (RVM) in i.v. serotonin-produced inhibition of the TF reflex. In Experiment 1, the effects of anesthetic blockade of the RVM on serotonin-produced inhibition of the TF were determined. Lidocaine attenuated the serotonin-produced inhibition of the TF reflex, but had no effect on the cardiovascular effects of serotonin. In Experiment 2, the effects of i.v. serotonin on neural activity in the RVM in intact and cardiopulmonary deafferented rats were determined. Neurons in the RVM were classified as ON and OFF cells, where ON cells were excited by noxious heat, and OFF cells were inhibited. The effects of i.v. serotonin on TF latency, blood pressure, and ON or OFF cell activity were then determined. In intact rats, serotonin produced a dose-dependent increase in TF latency, triphasic changes in blood pressure, and bi- or triphasic changes in ON or OFF cell activity. The changes in blood pressure included an initial sharp decrease in blood pressure (Bezold-Jarisch reflex), followed by a brief pressor response, followed by a delay depressor response. ON cells were generally excited, although there was a period during which the excitation decreased. OFF cells were initially excited, followed by a period of inhibition, followed by a second period of excitation. Bilateral cervical vagotomy attenuated the increase in TF latency, the Bezold-Jarisch reflex, and the excitation of OFF cells, and potentiated the excitation of ON cells and the pressor response. Bilateral sinoaortic deafferentation attenuated the Bezold-Jarisch reflex and potentiated the pressor response. These findings indicate that i.v. serotonin inhibits the TF reflex through at least two distinct mechanisms, one of which requires the RVM. In addition, serotonin produces a vagally mediated excitation of OFF cells and inhibition of ON cells that may mediate some of the antinociception.

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As efforts to improve screening for colon cancer have increased, so has the importance of routine flexible sigmoidoscopy. However, the procedure is still underused, and about half of primary care physicians who recommend it refer their patients to other physicians. Increased use of this valuable screening tool is an important goal in primary care practice. Drs Davis and Stanfield discuss the indications, contraindications, and goals of the procedure as well as special techniques and maneuvers that ensure its safety and efficiency.

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Outpatient laparoscopic cholecystectomy has become nearly mandatory in the current health care economic environment. This study determined the opinions of patients and their nurses regarding disability and pain after laparoscopic cholecystectomy. Using a 14-point questionnaire, 32 consecutive patients who underwent inpatient LC were surveyed. The nurses caring for these patients were surveyed with a nine-point questionnaire. Seventy-one percent of patients believed that they could not have been discharged the day of surgery; the nurses reported that 81% of the patients could not have gone home. Nausea and vomiting were common. Pain was rated as 9 or 10 in 19% of patients. Nurses reported that 56% of postoperative patients were not receptive to discharge teaching. Morning (16) versus afternoon (16) procedures were not different. Successful programs of outpatient LC must: 1) ensure adequate home support because patient capability will be limited, 2) optimize pain control, 3) minimize nausea and vomiting, and 4) deliver patient education preoperatively.

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Current trends in employer management of health-care plans are summarized, and the role of managed care is emphasized. Employers realize that employees perceive health-care plans as an important benefit and that attractive benefit plans will help in recruiting and retaining employees. At the same time, companies are faced with the need to find new ways in which to curtail the rising cost of health-benefit plans, which often constitute their largest and most uncontrollable budget item. Such techniques as more effective claims administration, plan design changes, plan financing arrangements, education of employees, and increased employee cost sharing are among the cost-containment actions that employers are implementing. Managed-care networks including health maintenance organizations are often viewed as the ultimate cost-containment model; however, the effectiveness of these evolving arrangements must be rigorously evaluated on the basis of appropriate performance criteria and documentation of achievement. Faced with cost-containment pressures, employers are taking a more assertive and informed role in health-plan purchasing decisions. The future course of health-care delivery will depend in large part on the response of corporate management to the challenge of ensuring that their employees receive quality health care at controllable costs.

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Analogs of cholecystokinin (Ac-CCK-7) in which Tyr(SO3H) was replaced with D-Tyr(SO3H), Tyr(m-SO3H), D-Tyr(m-SO3H) Tyr(o-SO3H) and D-Tyr(o-SO3H) were prepared by solid phase peptide synthesis, characterized by amino acid analysis, MS, UV, IR and tested in vivo for their ability to suppress food intake and in vitro (receptor binding). Comparison of the binding efficacy to food intake revealed a poor correlation. Ac-[Tyr(m-SO3H)]-CCK-7 retained substantial anorectic activity, whereas Ac-[Tyr(o-SO3H)-CCK-7 was essentially inactive. Ac-[D-Tyr(SO3H)]-CCK-7 and Ac-[D-Tyr(mSO3H)]-CCK-7 retained substantial biological activity. From these studies we conclude that the position of the negative charge on Tyr (meta or para) is important for anorectic activity, but the chirality of the alpha-carbon is not important for biological activity.

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An in-vitro system was used to study the effects of ATP depletion in the cells of the enamel organ and the use of the calcium ionophore A23187 on the mineralization of rat molar secretory stage enamel and 45Ca-movement through the enamel organ. Mineralization of the explants and 45Ca-uptake by the enamel were both enhanced by ATP depletion. No changes in these parameters were observed when the ionophore was added to the medium. The mechanism that limits the rate of calcium transport through the enamel organ during the secretory phase of enamel development is thus ATP-dependent. The result is consistent with the Takano-Crenshaw hypothesis for transcellular calcium transport. Use of the calcium ionophore A23187 failed to define further the nature of the calcium transport mechanism.

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Previous independent reports suggest that low platelet monoamine oxidase (MAO) activity and high serum dopamine-beta-hydroxylase (DBH) activity may be associated with alcoholism or vulnerability toward alcoholism. However, there are also contradictory reports in the literature with regard to each of these two enzymes. We measured both platelet MAO and serum DBH activity in alcoholics followed up at periodic intervals for 12 months after hospitalization for acute alcoholism. Platelet MAO activity in the alcoholics was significantly lower compared to that of nonpsychiatric controls throughout the 12-month period, whereas serum DBH activity in the alcoholics was essentially the same as control values. Thus, low platelet MAO activity, previously reported in a spectrum of clinical psychiatric disorders, appears to be a relatively stable phenomenon in chronic alcoholics irrespective of acute intoxication or pathophysiological factors associated with acute decompensation in individuals vulnerable to alcoholism.

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Previous reports suggest that high serum dopamine-beta-hydroxylase (DBH) activity may be associated with vulnerability to alcoholism. However, there are also contradictory studies in the literature. Therefore we measured serum DBH in chronic alcoholics followed for 12 months in a treatment programme after psychiatric hospitalization for acute alcoholism. Mean serum DBH activity in the alcoholics was unchanged from controls at 3 months, 6 months and 12 months following hospital discharge. These data imply that serum DBH activity does not provide a useful metabolic screen for vulnerability to chronic alcoholism. However, prospective studies of patients at high risk to develop alcoholism will be helpful in further clarification of this issue.

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There are now several studies in the literature which document low blood platelet monoamine oxidase (MAO) activity in alcoholics. However, these reports are in disagreement as to the stability of reduced enzyme activity over time. The present study provides evidence that reduced platelet MAO activity in alcoholics is a relatively stable phenomenon, independent of ethanol consumption and proximate factors of the illness which are associated with excessive ethanol consumption.

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Previous reports suggest that tricyclic antidepressants inhibit platelet monoamine oxidase (MAO) activity in vitro and in vivo. This study was undertaken to examine the relationship between tricyclic-mediated inhibition of platelet MAO and resolution of clinical signs and symptoms which are commonly associated with the depressive syndrome. The results indicate that the sedative-hypnotic effects of the tricyclics closely correlate with the magnitude of platelet MAO inhibition. It appears that these effects may be mediated through alterations in the metabolism of serotonin and/or the phenylethylamines.

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