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1.
Geohealth ; 7(12): e2023GH000971, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38098874

ABSTRACT

Exposure to environmental hazards is an important determinant of health, and the frequency and severity of exposures is expected to be impacted by climate change. Through a partnership with the U.S. National Aeronautics and Space Administration, the U.S. Centers for Disease Control and Prevention's National Environmental Public Health Tracking Network is integrating timely observations and model data of priority environmental hazards into its publicly accessible Data Explorer (https://ephtracking.cdc.gov/DataExplorer/). Newly integrated data sets over the contiguous U.S. (CONUS) include: daily 5-day forecasts of air quality based on the Goddard Earth Observing System Composition Forecast, daily historical (1980-present) concentrations of speciated PM2.5 based on the modern era retrospective analysis for research and applications, version 2, and Moderate Resolution Imaging Spectroradiometer (MODIS) daily near real-time maps of flooding (MCDWD). Data integrated into the CDC Tracking Network are broadly intended to improve community health through action by informing both research and early warning activities, including (a) describing temporal and spatial trends in disease and potential environmental exposures, (b) identifying populations most affected, (c) generating hypotheses about associations between health and environmental exposures, and (d) developing, guiding, and assessing environmental public health policies and interventions aimed at reducing or eliminating health outcomes associated with environmental factors.

2.
J Adv Model Earth Syst ; 14(6): e2021MS002852, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35864944

ABSTRACT

The NASA Goddard Earth Observing System (GEOS) Composition Forecast (GEOS-CF) provides recent estimates and 5-day forecasts of atmospheric composition to the public in near-real time. To do this, the GEOS Earth system model is coupled with the GEOS-Chem tropospheric-stratospheric unified chemistry extension (UCX) to represent composition from the surface to the top of the GEOS atmosphere (0.01 hPa). The GEOS-CF system is described, including updates made to the GEOS-Chem UCX mechanism within GEOS-CF for improved representation of stratospheric chemistry. Comparisons are made against balloon, lidar, and satellite observations for stratospheric composition, including measurements of ozone (O3) and important nitrogen and chlorine species related to stratospheric O3 recovery. The GEOS-CF nudges the stratospheric O3 toward the GEOS Forward Processing (GEOS FP) assimilated O3 product; as a result the stratospheric O3 in the GEOS-CF historical estimate agrees well with observations. During abnormal dynamical and chemical environments such as the 2020 polar vortexes, the GEOS-CF O3 forecasts are more realistic than GEOS FP O3 forecasts because of the inclusion of the complex GEOS-Chem UCX stratospheric chemistry. Overall, the spatial patterns of the GEOS-CF simulated concentrations of stratospheric composition agree well with satellite observations. However, there are notable biases-such as low NO x and HNO3 in the polar regions and generally low HCl throughout the stratosphere-and future improvements to the chemistry mechanism and emissions are discussed. GEOS-CF is a new tool for the research community and instrument teams observing trace gases in the stratosphere and troposphere, providing near-real-time three-dimensional gridded information on atmospheric composition.

3.
Earth Space Sci ; 8(7): e2021EA001743, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34435082

ABSTRACT

While multiple information sources exist concerning surface-level air pollution, no individual source simultaneously provides large-scale spatial coverage, fine spatial and temporal resolution, and high accuracy. It is, therefore, necessary to integrate multiple data sources, using the strengths of each source to compensate for the weaknesses of others. In this study, we propose a method incorporating outputs of NASA's GEOS Composition Forecasting model system with satellite information from the TROPOMI instrument and ground measurement data on surface concentrations. Although we use ground monitoring data from the Environmental Protection Agency network in the continental United States, the model and satellite data sources used have the potential to allow for global application. This method is demonstrated using surface measurements of nitrogen dioxide as a test case in regions surrounding five major US cities. The proposed method is assessed through cross-validation against withheld ground monitoring sites. In these assessments, the proposed method demonstrates major improvements over two baseline approaches which use ground-based measurements only. Results also indicate the potential for near-term updating of forecasts based on recent ground measurements.

4.
J Geophys Res Atmos ; 124(2): 1148-1169, 2019.
Article in English | MEDLINE | ID: mdl-32832312

ABSTRACT

Emissions of C2-C5 alkanes from the U.S. oil and gas sector have changed rapidly over the last decade. We use a nested GEOS-Chem simulation driven by updated 2011NEI emissions with aircraft, surface and column observations to 1) examine spatial patterns in the emissions and observed atmospheric abundances of C2-C5 alkanes over the U.S., and 2) estimate the contribution of emissions from the U.S. oil and gas industry to these patterns. The oil and gas sector in the updated 2011NEI contributes over 80% of the total U.S. emissions of ethane (C2H6) and propane (C3H8), and emissions of these species are largest in the central U.S. Observed mixing ratios of C2-C5 alkanes show enhancements over the central U.S. below 2 km. A nested GEOS-Chem simulation underpredicts observed C3H8 mixing ratios in the boundary layer over several U.S. regions and the relative underprediction is not consistent, suggesting C3H8 emissions should receive more attention moving forward. Our decision to consider only C4-C5 alkane emissions as a single lumped species produces a geographic distribution similar to observations. Due to the increasing importance of oil and gas emissions in the U.S., we recommend continued support of existing long-term measurements of C2-C5 alkanes. We suggest additional monitoring of C2-C5 alkanes downwind of northeastern Colorado, Wyoming and western North Dakota to capture changes in these regions. The atmospheric chemistry modeling community should also evaluate whether chemical mechanisms that lump larger alkanes are sufficient to understand air quality issues in regions with large emissions of these species.

6.
Clin Transplant ; 16(3): 233-9, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12010150

ABSTRACT

We report a previously unrecognized late complication of allograft lung transplantation - persistent recurrent atelectasis of the transplanted lung. The patient developed sudden, severe respiratory distress about 2 yr after a right lung transplant, because of acute atelectasis of her transplanted lung. Multiple transbronchial biopsies at the time revealed minimal inflammation and no evidence of rejection. She was treated with surfactant replacement therapy, and her collapsed lung fully expanded following surfactant installation. To eliminate the possibility of acquired deficiency of surfactant lipids or proteins, ultrastructural examination and immunostains for surfactant proteins were performed in a transbronchial lung biopsy. No deficiency of surfactant lipids or proteins was found. On ultrastructural examination of the lung biopsy, the number of Type II cells per alveolus and the number of lamellar bodies per square micron of Type II cell cross-sectional area was increased compared with an age-matched control. We conclude that synthesis of surfactant lipids and proteins was unimpaired and because of the patient's response to surfactant replacement therapy, that the increase in number of lamellar bodies could reflect a compensatory mechanism for a surfactant functional defect. The patient later developed breast carcinoma to which she succumbed. We raise the possibility that the functional surfactant defect is a hitherto unrecognized non-metastatic manifestation of malignancy.


Subject(s)
Lung Transplantation/adverse effects , Pulmonary Atelectasis/etiology , Female , Humans , Immunoenzyme Techniques , Middle Aged , Pulmonary Alveoli/metabolism , Pulmonary Surfactants/therapeutic use , Recurrence , Respiratory Insufficiency/etiology , Time Factors
8.
Ann Surg ; 234(4): 427-35; discussion 435-7, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11573036

ABSTRACT

OBJECTIVE: To analyze the short-term and midterm results of open and endoluminal repair of abdominal aortic aneurysms (AAA) in a large single-center series and specifically in octogenarians. METHODS: Between January 1997 and October 2000, 470 consecutive patients underwent elective repair of AAA. Conventional open repair (COR) was performed in 210 patients and endoluminal graft (ELG) repair in 260 patients. Ninety of the patients were 80 years of age or older; of these, 38 underwent COR and 52 ELG repair. RESULTS: Patient characteristics and risk factors were similar for both the entire series and the subgroup of patients 80 years or older. The overall complication rate was reduced by 70% or more in the ELG versus the COR groups. The postoperative death rate was similar for the COR and ELG groups in the entire series and lower (but not significantly) in the ELG 80 years or older subgroup versus the COR group. The 36-month rates of freedom from endoleaks, surgical conversion, and secondary intervention were 81%, 98.2%, and 88%, respectively. CONCLUSION: The short-term and midterm results of AAA repair by COR or ELG are similar. The death rate associated with this new technique is low and comparable, whereas the complication rate associated with COR in all patients and those 80 years or older in particular is greater and more serious than ELG repair. Long-term results will establish the role of ELG repair of AAA, especially in elderly and high-risk patients.


Subject(s)
Aortic Aneurysm, Abdominal/mortality , Aortic Aneurysm, Abdominal/surgery , Blood Vessel Prosthesis Implantation/methods , Vascular Surgical Procedures/methods , Adult , Age Factors , Aged , Aged, 80 and over , Angiography , Aortic Aneurysm, Abdominal/diagnostic imaging , Chi-Square Distribution , Elective Surgical Procedures , Endoscopy , Female , Humans , Male , Middle Aged , Postoperative Complications/surgery , Probability , Retrospective Studies , Risk Assessment , Sensitivity and Specificity , Statistics, Nonparametric , Survival Analysis , Treatment Outcome
9.
Pacing Clin Electrophysiol ; 24(6): 1041-2, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11449584

ABSTRACT

Percutaneous insertion of permanent pacemaker leads through the subclavian vein is an alternative to the cephalic vein approach. A rare occurrence and successful conservative management of extensive pneumomediastinum and subcutaneous emphysema without concomitant pneumothorax resulting from permanent transvenous pacemaker insertion in an 80-year-old man with syncope and arrhythmia is reported.


Subject(s)
Mediastinal Emphysema/etiology , Pacemaker, Artificial/adverse effects , Subcutaneous Emphysema/etiology , Aged , Aged, 80 and over , Humans , Male
10.
Chest ; 119(6): 1968-75, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11399738

ABSTRACT

The objective of the study was to describe a safe and effective treatment option for endobronchial complications after solid organ transplantation. A retrospective analysis was performed in a tertiary-care university hospital. The use of bronchoscopic argon plasma coagulation (APC) for the treatment of endobronchial lesions was studied in five solid organ transplant recipients. Four patients presented with variable degrees of endobronchial obstruction, and one patient presented with massive hemoptysis. Two of the patients with endobronchial obstruction were double lung transplant recipients who developed anastomotic strictures. The strictures were opened with endobronchial stents but became obstructed again by inflammatory granulation tissue overgrowth through the stent mesh. APC was used to maintain airway patency. One kidney transplant recipient developed pulmonary zygomycosis with secondary obstruction of the left main bronchus because of granulation tissue growth through endobronchial stents. Airway patency was reestablished with several treatments with APC. Another kidney transplant recipient developed subglottic and tracheal papillomatosis that was effectively removed with APC. A heart transplant recipient was referred with recurrent massive hemoptysis refractory to bronchial artery embolization. The bleeding was caused by hemorrhagic polypoid lesions, which were completely ablated by APC. Bronchoscopic use of the argon plasma coagulator is a safe and simple technique that can be used effectively to treat endobronchial pathology in solid organ transplant patients.


Subject(s)
Bronchial Diseases/surgery , Bronchoscopy , Laser Coagulation/methods , Organ Transplantation , Adult , Female , Heart Transplantation , Hemoptysis/surgery , Humans , Kidney Transplantation , Lung Transplantation , Male , Postoperative Complications , Retrospective Studies , Stents
12.
Dev Biol ; 231(2): 374-82, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11237466

ABSTRACT

nautilus (nau), the single Drosophila member of the bHLH-containing myogenic regulatory family of genes, is expressed in a subset of muscle precursors and differentiated fibers. It is capable of inducing muscle-specific transcription as well as myogenic transformation, and plays a role in the differentiation of a subset of muscle precursors into mature muscle fibers. In previous studies, the nau zygotic loss-of-function phenotype was determined using genetic deficiencies in which the gene is deleted. We note that this genetic loss-of-function phenotype differs from the loss-of-function phenotype determined using RNA interference (L. Misquitta and B. M. Paterson, 1999, Proc. Natl. Acad. Sci. USA 96, 1451-1456). The present study re-examines this loss-of-function phenotype using EMS-induced mutations that specifically alter the nau gene, and extends the genetic analysis to include the loss of both maternal and zygotic nau function. In brief, embryos lacking nau both maternally and zygotically are missing a distinct subset of muscle fibers, consistent with its apparent expression in a subset of muscle fibers. The muscle loss is tolerated, however, such that the loss of nau both maternally and zygotically does not result in lethality at any stage of development.


Subject(s)
Drosophila Proteins , Insect Proteins/genetics , Insect Proteins/physiology , Muscle Proteins , Mutation , Transcription Factors , Animals , Blotting, Southern , Cell Differentiation , Crosses, Genetic , DNA Mutational Analysis , Drosophila , Embryo, Nonmammalian/physiology , Female , Genotype , Immunohistochemistry , Larva/physiology , Male , Models, Biological , Models, Genetic , Muscles/cytology , Muscles/metabolism , Mutagenesis , Phenotype , Point Mutation , RNA/metabolism , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Time Factors , Transcription, Genetic , Zygote/metabolism
13.
Phys Rev Lett ; 84(23): 5443-6, 2000 Jun 05.
Article in English | MEDLINE | ID: mdl-10990964

ABSTRACT

Using a combination of the quartz crystal microbalance and surface plasmon resonance techniques, we have studied the spontaneous formation of supported lipid bilayers from small (approximately 25 nm) unilamellar vesicles. Together these experimental methods measure the amount of lipid adsorbed on the surface and the amount of water trapped by the lipid. With this approach, we have, for the first time, been able to observe in detail the progression from the adsorption of intact vesicles to rupture and bilayer formation. Monte Carlo simulations reproduce the data.


Subject(s)
Lipid Bilayers/chemistry , Liposomes/chemistry , Adsorption , Monte Carlo Method , Surface Plasmon Resonance , Surface Properties , Time Factors , Water/chemistry
14.
Ann Thorac Surg ; 69(6): 1670-4, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10892904

ABSTRACT

BACKGROUND: It is widely believed that bilateral thoracoscopic lung volume reduction (BTLVR) yields superior results when compared with unilateral thoracoscopic lung volume reduction (UTLVR) with regard to spirometry, functional capacity, oxygenation and quality of life results. METHODS: To address these issues, we compared the results of patients undergoing UTLVR (N = 338 patients) and BTLVR (N = 344 patients) from 1993 to 1998 at five institutions. Follow-up data were available on 671 patients (98.4%) between 6 and 12 months after surgery, and a patient self-assessment was obtained at a mean of 24 months. RESULTS: It was found that BTLVR provides superior improvement in measured postoperative percent change in FEV1 (L) (UTLVR 23.3% +/- 55.3 vs BTLVR 33% +/- 41, p = 0.04), FVC(L) (10.5% +/- 31.6 vs 20.3% +/- 34.3, p = 0.002) and RV(L) (-13% +/- -22 vs -22% +/- 17.9, p = 0.015). BTLVR also provides a slight improvement over UTLVR in patient's perception regarding improved quality of life (UTLVR 79% vs BTLVR 88%, p = 0.03) and dyspnea relief (71% vs 61%, p = 0.03). There was no difference in mean changes in PO2 (mm Hg) (UTLV 4.5 +/- 12.3 vs BTLVR 4.9 +/- 13.3, p = NS), 6-minute walk (UTLVR 26% +/- 66.1 vs BTLVR 31% +/- 59.6, p = NS) or decreased oxygen utilization (UTLVR 78% vs BTLVR 74%, p = NS). CONCLUSIONS: These data suggest that both UTLVR and BTLVR yield significant improvement, but the results of BTLVR seem to be superior with regard to spirometry, lung volumes, and quality of life.


Subject(s)
Pneumonectomy , Postoperative Complications/etiology , Pulmonary Emphysema/surgery , Thoracoscopy , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Middle Aged , Postoperative Complications/diagnosis , Pulmonary Emphysema/diagnosis , Quality of Life , Respiratory Function Tests , Treatment Outcome
15.
Eur J Cardiothorac Surg ; 17(6): 673-9, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10856858

ABSTRACT

OBJECTIVE: Most reports of thoracoscopic lung volume reduction (TLVR) are relatively small and early experiences from a single institution, factors which limit both the statistical validity and the applicability to the population at large. In order to address these shortcomings we undertook an analysis of the TLVR experience at five separate institutions to assess operative morbidity and identify predictors of mortality. METHODS: Questionnaires were sent to four groups of surgical investigators at five institutions actively performing TLVR. Data was requested regarding preoperative, operative and postoperative parameters. Twenty-five potential predictors of mortality were analyzed and seven proved to be at least marginally significant (P<0.10). These parameters were entered into a stepwise logistic regression analysis to identify independent predictors. RESULTS: The 682 patients (415 males, 267 females, mean age 64.0 years) underwent unilateral (410) or bilateral (272) TLVRs. Overall, operative mortality was 6% with half of the deaths resulting from respiratory causes. The remaining patients were discharged to home (88%), a rehabilitation facility (4%) or a ventilator facility (2%). There were 25 perioperative factors chosen representing clinically important indices such as spirometry, oxygenation, functional status, clinical and demographic variables. Univariate analysis identified seven variables as predictors of mortality (P<0.10) and these were entered into a stepwise logistic regression analysis. Only age, 6-min walk, gender (male 8%, female 3% mortality) and the procedure performed (unilateral 4.6%, bilateral 8%) were independent predictors while preoperative steroid therapy, preoperative oxygen administration, and time since smoking cessation dropped out of the model. The specific institution, learning curve (early vs. late experience), type of lung disease, spirometric indices and predicted maximum VO(2) were not significant predictors. CONCLUSION: This experience suggests that unilateral and bilateral lung volume reduction procedure can be performed with acceptable morbidity and mortality. Although age, gender, exercise capacity and the procedure performed are all independent predictors of mortality, the risk of operative death did not appear excessive in this fragile patient subset.


Subject(s)
Pneumonectomy/methods , Postoperative Complications/mortality , Pulmonary Emphysema/surgery , Thoracoscopy/methods , Adult , Aged , Evaluation Studies as Topic , Female , Follow-Up Studies , Humans , Logistic Models , Male , Middle Aged , Pneumonectomy/mortality , Predictive Value of Tests , Probability , Pulmonary Emphysema/mortality , Risk Assessment , Statistics, Nonparametric , Surveys and Questionnaires , Survival Analysis , Thoracoscopy/mortality , Treatment Outcome
16.
Chest ; 117(6): 1813-7, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10858425

ABSTRACT

We report the case of a 35-year-old woman who developed pulmonary alveolar proteinosis requiring multiple lavage treatments, in association with household exposure to ventilation system dust comprised at least partially by a cellulose fire-resistant fibrous insulation material. Scanning electron microscopy with energy-dispersive x-ray analysis documented the presence of spectral peaks consistent with the insulation material in transbronchial biopsy tissue. The patient showed symptomatic improvement once exposure to the insulation material had ceased. We believe that this case demonstrates an unusual association with pulmonary alveolar proteinosis. This case emphasizes the broad differential diagnosis for this histologic injury pattern and the need to thoroughly investigate environmental exposures in patients with unexplained pulmonary disease.


Subject(s)
Air Pollution, Indoor/adverse effects , Cellulose/adverse effects , Construction Materials/adverse effects , Mineral Fibers/adverse effects , Pulmonary Alveolar Proteinosis/etiology , Adult , Dust/adverse effects , Female , Humans , Lung/pathology , Microscopy, Electron, Scanning , Pulmonary Alveolar Proteinosis/diagnosis , Pulmonary Alveolar Proteinosis/pathology
17.
Intensive Care Med ; 26(12): 1850-6, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11271095

ABSTRACT

OBJECTIVE: To determine the morbidity and mortality of percutaneous dilational tracheostomy with bronchoscopic guidance when performed by medical intensivists. DESIGN: A retrospective analysis. SETTING: A tertiary care university hospital. PATIENTS: Fifty consecutive patients who underwent percutaneous dilational tracheostomy for prolonged mechanical ventilation. INTERVENTION: Bedside percutaneous dilational tracheostomy with bronchoscopic guidance. RESULTS: Seventeen women and 33 men with a mean age of 62 +/- 17 years. Operative mortality was 0 with four (8%) operative complications. Complications included one posterior tracheal abrasion, one anterior tracheal laceration, one episode of endobronchial hemorrhage requiring bronchoscopy, and one pneumothorax. Thirty-day mortality was 28% and overall mortality was 40%. All deaths were related to the patients' underlying disease. CONCLUSIONS: Percutaneous dilational tracheostomy with bronchoscopic guidance is a safe procedure when performed by experienced medical intensive care personnel in tertiary care institutions. Bronchoscopy helps to reduce the risk of major complications and aids in the management of minor complications.


Subject(s)
Bronchoscopy/adverse effects , Bronchoscopy/methods , Point-of-Care Systems , Tracheostomy/adverse effects , Tracheostomy/methods , Aged , Bronchoscopy/mortality , Clinical Protocols , Critical Care/methods , Female , Hemorrhage/etiology , Hospital Mortality , Hospitals, University , Humans , Male , Middle Aged , Missouri/epidemiology , Morbidity , Patient Selection , Pneumothorax/etiology , Point-of-Care Systems/standards , Respiratory Insufficiency/etiology , Respiratory Insufficiency/mortality , Respiratory Insufficiency/therapy , Retrospective Studies , Tracheostomy/instrumentation , Tracheostomy/mortality , Treatment Outcome
18.
World J Surg ; 23(11): 1148-55, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10501877

ABSTRACT

Surgical therapy has recently been reintroduced for the treatment of emphysema, and a number of investigators have used video-assisted thoracic surgical (VATS) techniques to accomplish lung volume reduction. The published reports differ with regard to patient selection, preoperative preparation, operative approach, and surgical technique. The results of these reports are reviewed and compared. Thoracoscopic lung volume reduction appears to be a useful part of the surgeon's armamentarium in managing patients with severe pulmonary emphysema.


Subject(s)
Pneumonectomy , Thoracic Surgery, Video-Assisted , Humans , Patient Selection , Pneumonectomy/methods , Postoperative Care , Preoperative Care , Pulmonary Emphysema/physiopathology , Pulmonary Emphysema/surgery , Survival Rate , Thoracic Surgery, Video-Assisted/methods , Treatment Outcome
19.
Ann Thorac Surg ; 68(6): 2026-31; discussion 2031-2, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10616971

ABSTRACT

BACKGROUND: It has been suggested that bilateral thoracoscopic lung volume reduction (BTLVR) yields significantly better long-term survival than unilateral thoracoscopic lung volume reduction (UTLVR). METHODS: All perioperative data were collected at the time of the procedure. Follow-up data were obtained during office visits or by telephone. RESULTS: A total of 673 patients underwent thoracoscopic LVR: 343 had either simultaneous or staged BTLVR and 330, UTLVR. As of July 1998, follow-up was available on 667 (99%) of the 673 patients with a mean follow-up of 24.3 months. The patients in the BTLVR group were significantly younger (62.6+/-8.0 years versus 65.4+/-8.1 years; p < 0.0001), had a higher preoperative arterial oxygen tension (69.7+/-12 mm Hg versus 65.3+/-11 mm Hg; p < 0.0001), and had a superior preoperative 6-minute walk performance (279.9+/-93.6 m [933+/-312 feet] versus 244.5+/-101.4 m [815+/-338 feet] p < 0.0001). There was no difference in the operative mortality rate between the two groups (UTLVR, 5.1%, and BTLVR, 7%). Actuarial survival rates for the UTLVR group at 1 year, 2 years, and 3 years were 86%, 75%, and 69%, respectively versus 90%, 81%, and 74%, respectively, for the BTLVR group (p = not significant). CONCLUSIONS: Contrary to previous reports, survival after BTLVR was not superior to that after UTLVR even though the former group appeared to have a lower risk preoperatively because of younger age, higher arterial oxygen tension, more advantageous anatomy, and better functional status. Despite thoracoscopic LVR, the actuarial mortality rate approached 30% at 3 years, and this calls into question whether this procedure offers any survival advantage to patients with end-stage emphysema.


Subject(s)
Pneumonectomy , Pulmonary Emphysema/surgery , Thoracoscopy , Aged , Cause of Death , Female , Follow-Up Studies , Humans , Male , Middle Aged , Pneumonectomy/adverse effects , Pneumonectomy/mortality , Postoperative Complications , Pulmonary Emphysema/mortality , Pulmonary Emphysema/physiopathology , Respiratory Mechanics , Survival Rate
20.
Dev Biol ; 202(2): 157-71, 1998 Oct 15.
Article in English | MEDLINE | ID: mdl-9769169

ABSTRACT

In the Drosophila embryo, nautilus is expressed in a subset of muscle precursors and differentiated fibers and is capable of inducing muscle-specific transcription, as well as myogenic transformation. In this study, we examine the consequences of nautilus loss-of-function on the development of the somatic musculature. Genetic and molecular characterization of two overlapping deficiencies, Df(3R)nau-9 and Df(3R)nau-11a4, revealed that both of these deficiencies remove the nautilus gene without affecting a common lethal complementation group. Individuals transheterozygous for these deficiencies survive to adulthood, indicating that nautilus is not an essential gene. These embryos are, however, missing a subset of muscle fibers, providing evidence that (1) some muscle loss can be tolerated throughout larval development and (2) nautilus does play a role in muscle development. Examination of muscle precursors in these embryos revealed that nautilus is not required for the formation of muscle precursors, but rather plays a role in their differentiation into mature muscle fibers. Thus, we suggest that nautilus functions in a subset of muscle precursors to implement their specific differentiation programs.


Subject(s)
Drosophila Proteins , Drosophila/embryology , Drosophila/physiology , Insect Proteins/physiology , Muscle Proteins , Muscle, Skeletal/embryology , Transcription Factors , Animals , Animals, Genetically Modified , Chromosome Mapping , Crosses, Genetic , Drosophila/genetics , Female , Gene Deletion , Gene Expression Regulation, Developmental , Genes, Insect , Genetic Complementation Test , Heterozygote , Insect Proteins/genetics , Larva/growth & development , Male , Muscle Development , Muscle Fibers, Skeletal/cytology , Muscle, Skeletal/growth & development , Myogenic Regulatory Factors/genetics , Myogenic Regulatory Factors/physiology , Phenotype , Vertebrates
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