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1.
Int Urol Nephrol ; 46(8): 1551-5, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24633698

ABSTRACT

INTRODUCTION: The presence of squamous carcinoma in situ (CIS) of the distal penis extending into the urethral meatus is generally considered a contraindication for glans-sparing procedures. Distal urethrectomy with subsequent reconstruction can provide an alternative approach toward urethral resection while providing penile preservation in select cases. Unfortunately, long-term oncologic outcomes with this approach are ill-defined. MATERIALS AND METHODS: Between 1988 and 2012, five patients at Indiana University Medical Center underwent distal urethrectomy with reconstruction for penile squamous CIS extending into the urethral meatus. This cohort was retrospectively reviewed to evaluate functional and oncological outcomes. RESULTS: Of the five patients, four presented with glanular lesions and were initially managed with Mohs procedure in three cases, and local excision in one. The final patient presented with extensive urethral disease and was managed with primary urethrectomy. Reconstruction was performed with penile skin pedicle grafts in four patients and perineal urethrostomy in one. Final pathologic stage was T1 in one patient and Tis in the remaining four. Follow-up ranged from 6 to 96 months. One local recurrence was verified; however, it occurred outside the urethral area. This was confirmed in the pathologic analysis after the patient underwent a partial penectomy. Meatal dilation was necessary in two patients 12 and 7 months after the procedure. CONCLUSION: Distal urethrectomy for penile squamous CIS extending into the urethral meatus is a valid alternative to achieve negative surgical margins while preserving a penile function. Oncologic outcomes appear acceptable but larger series are still warranted to confirm our findings.


Subject(s)
Carcinoma in Situ/pathology , Carcinoma in Situ/surgery , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/surgery , Penile Neoplasms/pathology , Penile Neoplasms/surgery , Urethra/pathology , Urethra/surgery , Aged , Aged, 80 and over , Humans , Male , Middle Aged , Neoplasm Invasiveness , Retrospective Studies
2.
Astrobiology ; 13(8): 740-73, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23924246

ABSTRACT

The prospect of a future soft landing on the surface of Europa is enticing, as it would create science opportunities that could not be achieved through flyby or orbital remote sensing, with direct relevance to Europa's potential habitability. Here, we summarize the science of a Europa lander concept, as developed by our NASA-commissioned Science Definition Team. The science concept concentrates on observations that can best be achieved by in situ examination of Europa from its surface. We discuss the suggested science objectives and investigations for a Europa lander mission, along with a model planning payload of instruments that could address these objectives. The highest priority is active sampling of Europa's non-ice material from at least two different depths (0.5-2 cm and 5-10 cm) to understand its detailed composition and chemistry and the specific nature of salts, any organic materials, and other contaminants. A secondary focus is geophysical prospecting of Europa, through seismology and magnetometry, to probe the satellite's ice shell and ocean. Finally, the surface geology can be characterized in situ at a human scale. A Europa lander could take advantage of the complex radiation environment of the satellite, landing where modeling suggests that radiation is about an order of magnitude less intense than in other regions. However, to choose a landing site that is safe and would yield the maximum science return, thorough reconnaissance of Europa would be required prior to selecting a scientifically optimized landing site.


Subject(s)
Exobiology , Geology , Jupiter , Space Flight , Oceans and Seas
3.
Science ; 331(6017): 575-8, 2011 Feb 04.
Article in English | MEDLINE | ID: mdl-21292976

ABSTRACT

Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO(2) seasonal polar caps. Numerous dunes in Mars' north polar region have experienced morphological changes within a Mars year, detected in images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter. Dunes show new alcoves, gullies, and dune apron extension. This is followed by remobilization of the fresh deposits by the wind, forming ripples and erasing gullies. The widespread nature of these rapid changes, and the pristine appearance of most dunes in the area, implicates active sand transport in the vast polar erg in Mars' current climate.


Subject(s)
Carbon Dioxide , Mars , Dry Ice , Extraterrestrial Environment
4.
Science ; 325(5936): 58-61, 2009 Jul 03.
Article in English | MEDLINE | ID: mdl-19574383

ABSTRACT

The Phoenix mission investigated patterned ground and weather in the northern arctic region of Mars for 5 months starting 25 May 2008 (solar longitude between 76.5 degrees and 148 degrees ). A shallow ice table was uncovered by the robotic arm in the center and edge of a nearby polygon at depths of 5 to 18 centimeters. In late summer, snowfall and frost blanketed the surface at night; H(2)O ice and vapor constantly interacted with the soil. The soil was alkaline (pH = 7.7) and contained CaCO(3), aqueous minerals, and salts up to several weight percent in the indurated surface soil. Their formation likely required the presence of water.


Subject(s)
Ice , Mars , Water , Calcium Carbonate , Extraterrestrial Environment , Hydrogen-Ion Concentration , Robotics , Spacecraft , Temperature
5.
Science ; 317(5845): 1706-9, 2007 Sep 21.
Article in English | MEDLINE | ID: mdl-17885125

ABSTRACT

Water has supposedly marked the surface of Mars and produced characteristic landforms. To understand the history of water on Mars, we take a close look at key locations with the High-Resolution Imaging Science Experiment on board the Mars Reconnaissance Orbiter, reaching fine spatial scales of 25 to 32 centimeters per pixel. Boulders ranging up to approximately 2 meters in diameter are ubiquitous in the middle to high latitudes, which include deposits previously interpreted as finegrained ocean sediments or dusty snow. Bright gully deposits identify six locations with very recent activity, but these lie on steep (20 degrees to 35 degrees) slopes where dry mass wasting could occur. Thus, we cannot confirm the reality of ancient oceans or water in active gullies but do see evidence of fluvial modification of geologically recent mid-latitude gullies and equatorial impact craters.


Subject(s)
Mars , Water , Extraterrestrial Environment , Geological Phenomena , Geology
6.
J Neurosci Res ; 80(4): 562-75, 2005 May 15.
Article in English | MEDLINE | ID: mdl-15825192

ABSTRACT

Relatively few immune-activated and virus-infected mononuclear phagocytes (MP; perivascular macrophages and microglia) may affect widespread neuronal dysfunction during human immunodeficiency virus type 1 (HIV-1)-associated dementia (HAD). Indeed, histopathological evidence of neuronal dropout often belies the extent of cognitive impairment. To define relationships between neuronal function and histopathology, proton magnetic resonance spectroscopic imaging (1H MRSI) and hippocampal long-term potentiation (LTP) were compared with neuronal and glial immunohistology in a murine model of HIV-1 encephalitis (HIVE). HIV-1(ADA)-infected human monocyte-derived macrophages (MDM) were stereotactically injected into the subcortex of severe combined immunodeficient (SCID) mice. Sham-operated and unmanipulated mice served as controls. Seven days after cell injection, brain histological analyses revealed a focal giant cell encephalitis, with reactive astrocytes, microgliosis, and neuronal dropout. Strikingly, significant reductions in N-acetyl aspartate concentration ([NAA]) and LTP levels in HIVE mice were in both injected and contralateral hemispheres and in brain subregions, including the hippocampus, where neuropathology was limited or absent. The data support the importance of 1H MRSI as a tool for assessing neuronal function for HAD. The data also demonstrate that a highly focal encephalitis can produce global deficits for neuronal function and metabolism.


Subject(s)
AIDS Dementia Complex/pathology , Aspartic Acid/analogs & derivatives , Cognition Disorders/pathology , HIV-1 , Magnetic Resonance Spectroscopy , AIDS Dementia Complex/complications , AIDS Dementia Complex/physiopathology , Animals , Aspartic Acid/metabolism , Brain Mapping , Calcium-Binding Proteins/metabolism , Capsid Proteins/metabolism , Choline/metabolism , Cognition Disorders/etiology , Cognition Disorders/virology , Creatine/metabolism , Disease Models, Animal , Electric Stimulation/methods , Functional Laterality , Glial Fibrillary Acidic Protein/metabolism , HIV Infections/pathology , Hippocampus/physiopathology , Hippocampus/virology , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Long-Term Potentiation/physiology , Long-Term Potentiation/radiation effects , Magnetic Resonance Imaging/methods , Male , Mice , Mice, SCID , Microfilament Proteins , Microtubule-Associated Proteins/metabolism , Phosphopyruvate Hydratase/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 1 , Protein Tyrosine Phosphatase, Non-Receptor Type 11 , Protein Tyrosine Phosphatases/metabolism , Protons , Time Factors , Vimentin/metabolism
7.
J Pharmacol Exp Ther ; 297(3): 1016-24, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11356924

ABSTRACT

The role of protein kinase C and intracellular Ca(2+) on amphetamine-mediated dopamine release through the norepinephrine plasmalemmal transporter in undifferentiated PC12 cells was investigated. The selective protein kinase C inhibitor chelerythrine completely inhibited endogenous dopamine release elicited by 1 microM amphetamine. Direct activation of protein kinase C increased dopamine release in a Ca(2+)-insensitive, imipramine-sensitive manner and the release was not additive with amphetamine. Exocytosis was not involved since these events were not altered by either deletion of extracellular Ca(2+) or reserpine pretreatment. Down-regulation of protein kinase C activity by long-term phorbol ester treatment resulted in a dramatic decrease in amphetamine-mediated dopamine release with no apparent effect on [(3)H]dopamine uptake. To more completely examine a role for Ca(2+), intracellular Ca(2+) was chelated in the cells. Depletion of intracellular Ca(2+) considerably decreased dopamine release in response to 1 microM amphetamine compared with vehicle-treated cells, but had no effect on the [(3)H]dopamine uptake. Thus, our results suggest that amphetamine-mediated dopamine release through the plasmalemmal norepinephrine transporter is highly dependent on protein kinase C activity and intracellular but not extracellular Ca(2+). Furthermore, protein kinase C and intracellular Ca(2+) appear to regulate [(3)H]dopamine inward transport and amphetamine-mediated outward transport of dopamine independently in PC12 cells.


Subject(s)
Amphetamine/pharmacology , Calcium/metabolism , Carrier Proteins/metabolism , Dopamine/metabolism , Protein Kinase C/metabolism , Symporters , Animals , Biological Transport/drug effects , Cell Differentiation , Dopamine/pharmacokinetics , Down-Regulation/drug effects , Egtazic Acid/analogs & derivatives , Egtazic Acid/pharmacology , Enzyme Activation/drug effects , Enzyme Activators/pharmacology , Extracellular Space/metabolism , Intracellular Fluid/metabolism , Norepinephrine Plasma Membrane Transport Proteins , PC12 Cells , Pheochromocytoma/metabolism , Protein Kinase C/antagonists & inhibitors , Rats , Synaptic Vesicles/metabolism , Tetradecanoylphorbol Acetate/pharmacology
9.
Environ Microbiol ; 3(3): 205-19, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11321537

ABSTRACT

We have used a combination of microbiological, molecular biological and stable isotope methods to relate specific microbial populations to elemental cycling at an offshore site in Lake Michigan. Several lines of evidence suggest that atmospheric N2 may be a significant source of nitrogen to the lake. Particulate organic nitrogen (PON) at approximately equals 10-15m depth in July and October had a delta15N of 0.5-1.5%o. These values closely reflect the 15N composition of atmospheric N2, suggesting biological nitrogen fixation. Historical data show a developing late-summer N:P minimum at approximately equals 15 m; low abundance of inorganic nitrogen relative to phosphorus favours species able to acquire atmospheric nitrogen. Microscopic examination of October water samples revealed abundant heterocystous cyanobacteria, including Nodularia sp. Potentially nitrogen-fixing Anabaena spp. have been found in Lake Michigan before but, to our knowledge, this is the first report of Nodularia. Finally, we have amplified both cyanobacterial and non-cyanobacterial nifH sequences (encoding the nitrogenase iron protein) from lakewater samples, evidence for the presence of bacteria capable of nitrogen fixation. The surface waters of Lake Michigan are considered to be phosphate limited in the stratified season and, under these conditions, energetically expensive nitrogen fixation is expected to be uncompetitive with assimilation of combined nitrogen. Our results suggest that, from both microbiological and biogeochemical perspectives, this may be an oversimplification.


Subject(s)
Cyanobacteria/isolation & purification , Cyanobacteria/metabolism , Fresh Water/microbiology , Nitrogen Fixation/genetics , Water Microbiology , Animals , Carbon Isotopes , Cloning, Molecular , Cyanobacteria/genetics , DNA, Bacterial/genetics , Fresh Water/parasitology , Genes, Bacterial/genetics , Michigan , Molecular Sequence Data , Nitrogen Isotopes , Oxidoreductases/genetics , Phylogeny , Plankton/isolation & purification , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics
10.
Am J Respir Crit Care Med ; 162(2 Pt 1): 593-8, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10934092

ABSTRACT

A randomized, double-blind, placebo-controlled, parallel-group study including 481 children at 37 centers in the United States demonstrated the efficacy and safety of budesonide inhalation suspension in doses of 0.25 mg once daily, 0.25 mg twice daily, 0.5 mg twice daily, and 1.0 mg daily in infants and young children with persistent asthma. The retrospective analysis presented here compares the efficacy of treatment with the suspension administered through a face mask or mouthpiece. All patients receiving budesonide inhalation suspension via face mask or mouthpiece showed clinical improvements in nighttime and daytime asthma symptoms as compared with administration of a placebo. The improvements were of similar magnitude as those observed in an analysis of all patients treated. Improvements in nighttime asthma symptoms were statistically significant with budesonide at 0.25 mg daily (p = 0.040), 0.25 mg twice daily (p = 0.008), and 0.5 mg twice daily (p = 0.046) delivered by face mask. In patients using mouthpieces, nighttime asthma symptoms improved significantly in the 0.25-mg twice-daily (p = 0.005) and 1.0-mg daily (p = 0.035) groups. Patients receiving budesonide at 0.5 mg twice daily via a face mask improved significantly in daytime asthma symptoms (p = 0.009). The use of breakthrough medication was reduced in patients receiving budesonide via face masks or mouthpieces relative to placebo, and treatment was well tolerated in all study groups. This retrospective analysis suggests that nebulized budesonide inhalation suspension can be administered effectively by either face mask or mouthpiece to young children with persistent asthma.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Asthma/drug therapy , Budesonide/administration & dosage , Masks , Administration, Inhalation , Administration, Topical , Child , Double-Blind Method , Drug Administration Schedule , Female , Glucocorticoids , Humans , Infant , Male , Nebulizers and Vaporizers , Retrospective Studies , Suspensions , Treatment Outcome
11.
Appl Environ Microbiol ; 66(7): 3119-24, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10877818

ABSTRACT

A modified nested reverse transcriptase PCR (RT-PCR) method was used to detect the expression of nitrogenase genes in meso-oligotrophic Lake George, New York. Net (>20-microm pore size) plankton samples collected from two sites (Dome Island and Hague Marina) were extracted for total RNA and genomic DNA to determine the identity of diazotrophic organisms that were present and those that were actively expressing nitrogenase genes. Phylogenetic analysis of individual sequences cloned from PCR amplifications showed that there were phylogenetically diverse groups of bacteria that possessed a nifH gene, including representatives of unicellular and filamentous cyanobacteria, the alpha- and gamma-subdivisions of the division Proteobacteria (alpha- and gamma-proteobacteria), and a previously undefined group of bacteria. The phylotypes cloned from RT-PCR amplifications, which were actively expressing nifH transcripts, clustered with the unicellular and filamentous cyanobacteria, alpha-proteobacteria, and the novel bacterial cluster. No bacterial sequences were found which clustered with sequences from cluster II (alternative nitrogenases), III (nitrogenases in strict anaerobes), or IV (nifH-like sequences). These results indicate that there were several distinct groups of nitrogen-fixing microorganisms in the net plankton from both sampling sites and that most of the groups had representative phylotypes that were actively expressing nitrogenase genes.


Subject(s)
Bacteria/isolation & purification , Fresh Water/microbiology , Oxidoreductases/genetics , Plankton/microbiology , Reverse Transcriptase Polymerase Chain Reaction/methods , Alphaproteobacteria/genetics , Alphaproteobacteria/isolation & purification , Animals , Bacteria/classification , Bacteria/genetics , Bacteria/metabolism , Cyanobacteria/genetics , Cyanobacteria/isolation & purification , Gammaproteobacteria/genetics , Gammaproteobacteria/isolation & purification , Molecular Sequence Data , New York , Oxidoreductases/metabolism , Phylogeny
12.
J Pediatr Psychol ; 25(4): 193-214; discussion 215-8, 219-24, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10814687

ABSTRACT

OBJECTIVE: To review the medical and psychological literature concerning enuresis treatments in light of the Chambless criteria for empirically supported treatment. METHOD: A systematic search of the medical and psychological literature was performed using Medline and Psychlit. RESULTS: Several review studies and numerous well-controlled experiments have clearly documented the importance of the basic urine alarm alone as a necessary component in the treatment of enuresis or combined with the "Dry-Bed Training" intervention, establishing them as "effective treatments." Other multicomponent behavioral interventions that also include the urine alarm such as "Full Spectrum Home Training" have further improved the outcome for bed-wetters, but are classified as "probably efficacious" at this time because independent researchers have not replicated them. Less rigorously examined approaches that focus on improving compliance with treatment or include a "cognitive" focus (i.e., hypnosis) warrant further study. CONCLUSIONS: We recommend a "biobehavioral" perspective in the assessment and treatment of bed-wetting and suggest that combining the urine alarm with desmopressin offers the most promise and could well push the already high success rates of conditioning approaches closer to 100%. Much important work is yet to be completed that elucidates the mechanism of action for the success of the urine alarm and in educating society about its effectiveness so that its availability is improved.


Subject(s)
Behavior Therapy/methods , Enuresis/therapy , Biofeedback, Psychology , Child , Clinical Trials as Topic , Deamino Arginine Vasopressin/therapeutic use , Enuresis/drug therapy , Equipment and Supplies , Evidence-Based Medicine , Humans , Renal Agents/therapeutic use , Treatment Outcome
13.
J Pediatr Psychol ; 25(4): 225-54; discussion 255-6, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10814690

ABSTRACT

OBJECTIVE: To review the empirical research examining behavioral and medical treatments for constipation and fecal incontinence. METHOD: Sixty-five articles investigating intervention efficacy were identified and reviewed. Twenty-three of the studies were excluded because they were case studies or were less well-controlled single-case designs. The intervention protocol for each study was identified and coded, with studies employing the same interventions matched and evaluated according to the Chambless criteria. RESULTS: From the literature base to date, no well-established interventions have emerged. However, four probably efficacious treatments and three promising interventions were identified. Two different medical interventions plus positive reinforcement fit the criteria for the probably efficacious category (one with fiber recommendation and one without). Three biofeedback plus medical interventions fit efficacy category criteria: one probably efficacious for constipation with abnormal defecation dynamics (full medical intervention plus biofeedback for paradoxical contraction), and two fit the promising intervention criteria for constipation and abnormal defecation dynamics (full medical intervention plus biofeedback for EAS strengthening, correction of paradoxical contraction and home practice; and biofeedback focused on correction of paradoxical contraction, medical intervention without fiber recommendation, and positive reinforcement). Two extensive behavioral interventions plus medical intervention also met efficacy criteria for constipation plus incontinence (medical intervention without laxative maintenance plus positive reinforcement, dietary education, goal setting, and skills building presented in a small-group format fits criteria for a promising intervention; and positive reinforcement and skills building focused on relaxation of the EAS during defecation, but without biofeedback, plus medical intervention meets the probably efficacious criteria). CONCLUSIONS: A discussion of the current weaknesses in this research area follows. Specific recommendations for future research are made including greater clarity in treatment protocol and sample descriptions, reporting cure rates rather than success rates, utilization of adherence checks, and investigation of potential differential outcomes for subgroups of children with constipation and incontinence.


Subject(s)
Behavior Therapy/standards , Constipation/therapy , Encopresis/therapy , Psychology, Child/methods , Biofeedback, Psychology , Child , Clinical Trials as Topic , Constipation/psychology , Encopresis/psychology , Evidence-Based Medicine , Humans , Treatment Outcome
14.
Plant Mol Biol ; 41(1): 89-104, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10561071

ABSTRACT

The daily cycle of nitrogenase expression in the marine filamentous nonheterocystous cyanobacterium Trichodesmium spp. is controlled by a circadian rhythm. We evaluated the rhythm of two key photosynthesis genes, psbA of photosystem II and psaA of photosystem I, in Trichodesmium sp. IMS 101 using the 3 criteria for an endogenous rhythm. The transcript abundance of psbA and psaA transcripts oscillated with a period of ca. 24 h under a 12 h light/12 h dark regime. At 24 degrees C and 28 degrees C the cyclic pattern of transcript abundance was maintained for at least 58 h under constant light conditions, whereas the periods were about 24 h at 24 degrees C, and 26-30 h at the higher temperature. The cycles of psbA and psaA gene expression were entrained using light-dark cues. Transcription of nifHDK was initiated prior to the light period, followed by psbA and finally psaA. There was a 90 degrees (6 h) phase difference between the net accumulation of nifHDK and psbA transcripts, as well as between that of psbA and psaA transcripts. Results of inhibitor experiments indicated that psbA and psaA transcription was regulated differently by initiation and degradation during the light period. Short-term changes of light conditions resulted in significant effects on psbA transcription and nitrogenase activity, but had less of an effect on psaA and nifHDK transcription.


Subject(s)
Cyanobacteria/genetics , Genes, Plant/genetics , Nitrogen Fixation/genetics , Photosynthesis/genetics , Photosystem I Protein Complex , Bacterial Proteins/genetics , Blotting, Northern , Blotting, Southern , Circadian Rhythm , Cyanobacteria/growth & development , Cyanobacteria/radiation effects , DNA/analysis , DNA/genetics , Gene Expression Regulation/radiation effects , Molecular Sequence Data , Photoperiod , Photosynthetic Reaction Center Complex Proteins/genetics , Photosystem II Protein Complex , RNA/genetics , RNA/metabolism , RNA/radiation effects , Temperature , Time Factors , Transcription, Genetic/radiation effects
15.
J Allergy Clin Immunol ; 104(4 Pt 2): 191-9, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10518846

ABSTRACT

This paper reviews the results from 3 randomized, double-blind, placebo-controlled, multicenter studies that assessed the efficacy and safety of once- and twice-daily dosing of budesonide inhalation suspension (BIS) in infants and young children with persistent asthma. In children with mild persistent asthma that was previously treated with bronchodilators or noncorticosteroid anti-inflammatory agents (study A), nighttime and daytime asthma symptoms were significantly improved in 0.25-mg once daily, 0.5-mg once daily, and 1.0-mg once daily BIS treatment groups compared with placebo (P

Subject(s)
Anti-Asthmatic Agents/administration & dosage , Asthma/drug therapy , Budesonide/administration & dosage , Administration, Inhalation , Anti-Asthmatic Agents/adverse effects , Asthma/physiopathology , Budesonide/adverse effects , Child , Child, Preschool , Circadian Rhythm , Double-Blind Method , Drug Administration Schedule , Female , Forced Expiratory Volume , Humans , Infant , Male , Peak Expiratory Flow Rate , Placebos , Severity of Illness Index , Suspensions , Treatment Failure
16.
Pediatrics ; 103(2): 414-21, 1999 Feb.
Article in English | MEDLINE | ID: mdl-9925834

ABSTRACT

RATIONALE: Topical antiinflammatory medications such as inhaled corticosteroids are recommended for therapy of asthma, but no formulation suitable for administration to infants and young children is available in the United States. METHODS: This was a 12-week, multicenter, double-blind, randomized, parallel-group study comparing the efficacy and safety of four dosing regimens of bude-sonide inhalation suspension (BIS) or placebo in 480 asthmatic infants and children (64% boys), ages 6 months to 8 years, with moderate persistent asthma. Approximately 30% of children were previously on inhaled corticosteroids that were discontinued before the study. Active treatments were comprised of BIS 0.25 mg once daily (QD), 0.25 mg twice a day (BID), 0.5 mg BID, or 1.0 mg QD. Efficacy was assessed by twice daily recording at home of asthma symptom scores and use of rescue medication, and discontinuation from the study because of worsening asthma and/or a requirement for systemic steroids. Peak flow measurements were recorded twice daily on diary and spirometry was recorded at clinic visits for those children able to perform these tests. Safety was assessed by reported adverse events and by cortisol testing (adrenocorticotropic hormone stimulation) in a subset of patients. RESULTS: Patients enrolled had an average duration of asthma of 34 months; the mean asthma symptom score was approximately 1.3 (scale of 0-3). All dosing regimens with BIS produced statistically significant improvement in various clinical efficacy measures for asthma control compared with placebo. The lowest dose used, 0.25 mg QD, was efficacious but with fewer efficacy parameters than seen with the other doses administered. Separation between active treatment and placebo in daytime and nighttime symptom scores were observed by week 2 of treatment for all BIS treatment regimens. A significant increase in peak flow measurement was observed in most active treatment groups compared with placebo in the subset of children able to do pulmonary function testing. All treatment groups showed numerical improvement in forced expiratory volume in 1 second but only the 0.5-mg BID dose was significantly different from placebo. Adverse events for the entire group and response to adrenocorticotropic hormone in a subgroup of children who underwent cortisol testing before and at the end of the treatment period were no different in budesonide-treated patients in comparison to placebo. CONCLUSION: Results of this study demonstrate that BIS is effective and safe for infants and young children with moderate persistent asthma in a multiple dose range, and that QD dosing is an important option to be considered by the prescribing physician.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Asthma/drug therapy , Budesonide/administration & dosage , Administration, Inhalation , Child , Child, Preschool , Double-Blind Method , Drug Administration Schedule , Female , Humans , Infant , Male , Treatment Outcome
17.
Appl Environ Microbiol ; 64(9): 3444-50, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9726895

ABSTRACT

Oligotrophic oceanic waters of the central ocean gyres typically have extremely low dissolved fixed inorganic nitrogen concentrations, but few nitrogen-fixing microorganisms from the oceanic environment have been cultivated. Nitrogenase gene (nifH) sequences amplified directly from oceanic waters showed that the open ocean contains more diverse diazotrophic microbial populations and more diverse habitats for nitrogen fixers than previously observed by classical microbiological techniques. Nitrogenase genes derived from unicellular and filamentous cyanobacteria, as well as from the alpha and gamma subdivisions of the class Proteobacteria, were found in both the Atlantic and Pacific oceans. nifH sequences that cluster phylogenetically with sequences from sulfate reducers or clostridia were found associated with planktonic crustaceans. Nitrogenase sequence types obtained from invertebrates represented phylotypes distinct from the phylotypes detected in the picoplankton size fraction. The results indicate that there are in the oceanic environment several distinct potentially nitrogen-fixing microbial assemblages that include representatives of diverse phylotypes.


Subject(s)
Cyanobacteria/isolation & purification , Gram-Negative Bacteria/isolation & purification , Nitrogen Fixation , Nitrogenase/genetics , Oxidoreductases , Seawater/microbiology , Amino Acid Sequence , Atlantic Ocean , Cyanobacteria/enzymology , Cyanobacteria/genetics , Genetic Variation , Gram-Negative Bacteria/enzymology , Gram-Negative Bacteria/genetics , Molecular Sequence Data , Pacific Ocean , Phylogeny , Polymerase Chain Reaction , Water Microbiology
18.
J Bacteriol ; 180(14): 3598-605, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9658003

ABSTRACT

Recent studies suggested that the daily cycle of nitrogen fixation activity in the marine filamentous nonheterocystous cyanobacterium Trichodesmium sp. is controlled by a circadian rhythm. In this study, we evaluated the rhythm of nitrogen fixation in Trichodesmium sp. strain IMS 101 by using the three criteria for an endogenous rhythm. Nitrogenase transcript abundance oscillated with a period of approximately 24 h, and the cycle was maintained even under constant light conditions. The cyclic pattern of transcript abundance was maintained when the culture was grown at 24 and 28.5 degrees C, although the period was slightly longer (26 h) at the higher temperature. The cycle of gene expression could be entrained with light-dark cues. Results of inhibitor experiments indicated that transcript abundance was regulated primarily by transcription initiation, rather than by degradation. The circadian rhythm, the first conclusively demonstrated endogenous rhythm in a filamentous cyanobacterium, was also reflected in nitrogenase MoFe protein abundance and patterns of Fe protein posttranslational modification-demodification.


Subject(s)
Bacterial Proteins/genetics , Circadian Rhythm , Cyanobacteria/enzymology , Nitrogenase/genetics , Oxidoreductases , Bacterial Proteins/metabolism , Cyanobacteria/genetics , Gene Expression Regulation, Bacterial , Molybdoferredoxin/metabolism , Nitrogenase/metabolism , RNA, Messenger/metabolism , Temperature
19.
Antarct Sci ; 10(1): 31-8, 1998 Mar.
Article in English | MEDLINE | ID: mdl-11541256

ABSTRACT

Year-round temperature measurements at 1600 m elevation during 1994 in the Asgard Range Antarctica, indicate that the mean annual frost point of the ice-cemented ground, 25 cm below the surface, is -21.7 +/- 0.2 degrees C and the mean annual frost point of the atmosphere is -27.5 +/- 1.0 degrees C. The corresponding mean annual temperatures are -24.9 degrees C and -23.3 degrees C. These results imply that there is a net flux of water vapour from the ice to the atmosphere resulting in a recession of the ice-cemented ground by about 0.4-0.6 mm yr-1. The level of the ice-cemented permafrost is about 12 cm below the level of dry permafrost. The summer air temperatures would have to increase about 7 degrees C for thawing temperatures to just reach the top of the subsurface ice. Either subsurface ice at this location is evaporating over time or there are sporadic processes that recharge the ice and maintain equilibrium over long timescales.


Subject(s)
Ice , Soil/analysis , Temperature , Antarctic Regions , Cold Climate , Desert Climate , Humidity
20.
Appl Environ Microbiol ; 64(12): 5067, 1998 Dec.
Article in English | MEDLINE | ID: mdl-16349571

ABSTRACT

[This corrects the article on p. 3444 in vol. 64, PMID: 9726895.].

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