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1.
South Med J ; 94(7): 738-40, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11531185

ABSTRACT

A case of massive postoperative ascites in a woman treated for endometrial cancer is reported. A workup for typical causes of ascites yielded negative results, prompting a more detailed analysis of the patient's condition. Hypothyroidism was discovered. After correction of the hypothyroidism, the ascites slowly resolved. Since myxedema is an uncommon cause of ascites, this is usually a diagnosis of exclusion. However, hypothyroidism must be ruled out to prevent unnecessary and possibly inappropriate treatments for ascites.


Subject(s)
Adenocarcinoma/surgery , Ascites/etiology , Endometrial Neoplasms/surgery , Myxedema/complications , Pleural Effusion/complications , Postoperative Complications/diagnosis , Aged , Ascites/diagnostic imaging , Female , Humans , Paracentesis , Recurrence , Tomography, X-Ray Computed , Treatment Outcome
2.
Plant Physiol ; 123(2): 575-88, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10859187

ABSTRACT

Acquired thermotolerance is a complex physiological phenomenon that enables plants to survive normally lethal temperatures. This study characterizes the temperature sensitivity of Arabidopsis using a chlorophyll accumulation bioassay, describes a procedure for selection of acquired thermotolerance mutants, and provides the physiological characterization of one mutant (AtTS02) isolated by this procedure. Exposure of etiolated Arabidopsis seedlings to 48 degrees C or 50 degrees C for 30 min blocks subsequent chlorophyll accumulation and is eventually lethal. Arabidopsis seedlings can be protected against the effects of a 50 degrees C, 30-min challenge by a 4-h pre-incubation at 38 degrees C. By the use of the milder challenge, 44 degrees C for 30 min, and protective pretreatment, mutants lacking components of the acquired thermotolerance system were isolated. Putative mutants isolated by this procedure exhibited chlorophyll accumulation levels (our measure of acquired thermotolerance) ranging from 10% to 98% of control seedling levels following pre-incubation at 38 degrees C and challenge at 50 degrees C. The induction temperatures for maximum acquired thermotolerance prior to a high temperature challenge were the same in AtTS02 and RLD seedlings, although the absolute level of chlorophyll accumulation was reduced in the mutant. Genetic analysis showed that the loss of acquired thermotolerance in AtTS02 was a recessive trait. The pattern of proteins synthesized at 25 degrees C and 38 degrees C in the RLD and AtTS02 revealed the reduction in the level of a 27-kD heat shock protein in AtTS02. Genetic analysis showed that the reduction of this protein level was correlated with the acquired thermotolerance phenotype.


Subject(s)
Arabidopsis/genetics , Hot Temperature , Mutation , Arabidopsis/physiology , Plant Proteins/isolation & purification
3.
J Soc Gynecol Investig ; 4(6): 310-5, 1997.
Article in English | MEDLINE | ID: mdl-9408887

ABSTRACT

OBJECTIVE: To assess, in the human endometrial cell line HEC-1-A, the presence of protein tyrosine phosphatase 1D (PTP1D) and the possible regulation of its mRNA expression by mitogens such as forskolin (an agent that increases intracellular cyclic adenosine monophosphate [cAMP] levels), epidermal growth factor (EGF), and insulin-like growth factor-I (IGF-I). METHODS: Cells were grown to confluence and maintained in serum-free media for 24 hours before treatment. Cells were exposed to forskolin, EGF, and IGF-I for increasing time periods (0, 1, 3, 6, and 24 hours), and PTP1D mRNA expression was determined by Northern blot analysis. In addition, cells were incubated with increasing doses of forskolin (final concentrations: 1, 5, 10, 20, and 30 mumol/L) for 6 hours. RESULTS: When treated with the various mitogens, cells increased their stimulation of PTP1D mRNA expression in a time- and dose-dependent fashion. Specifically, forskolin, EGF, and IGF-I induced maximal mRNA expression at 6, 3, and 6 hours, respectively. Expression induced by forskolin, EGF, and IGF-I was five, three, and six times control levels, respectively. At a dose of 10 mumol/L, forskolin induced PTP1D mRNA expression almost two times higher than control values. CONCLUSION: These data suggest that in human endometrial carcinomas, cAMP, EGF, and IGF-I may regulate the expression of PTP1D mRNA, which may, in turn, play a role in uncontrolled cell proliferation and neoplastic transformation.


Subject(s)
Adenocarcinoma/metabolism , Endometrial Neoplasms/chemistry , Endometrial Neoplasms/pathology , Growth Substances/pharmacology , Protein Tyrosine Phosphatases/genetics , RNA, Messenger/metabolism , Adenocarcinoma/pathology , Blotting, Northern , Cell Division/drug effects , Cell Transformation, Neoplastic/drug effects , Colforsin/pharmacology , Dose-Response Relationship, Drug , Endometrial Neoplasms/metabolism , Epidermal Growth Factor/pharmacology , Epidermal Growth Factor/physiology , Female , Humans , Insulin-Like Growth Factor I/pharmacology , Insulin-Like Growth Factor I/physiology , Intracellular Signaling Peptides and Proteins , Protein Tyrosine Phosphatase, Non-Receptor Type 11 , Protein Tyrosine Phosphatase, Non-Receptor Type 6 , Protein Tyrosine Phosphatases/metabolism , Time Factors , Tumor Cells, Cultured
5.
Neuropsychopharmacology ; 14(1): 55-66, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8719030

ABSTRACT

Benzodiazepine (BDZ) receptor ligands with varying intrinsic efficacies [RO19-4603, 0.02-0.15 mg/kg; FG 7142 1-16 mg/kg; DMCM, 1-8 mg/kg; RO16-6028 (bretazenil), 8-32 mg/kg] in modulating GABAergic activity were examined for the ability to alter palatability-induced ethanol (EtOH) intake in the alcohol-nonpreferring (NP) line of rats. NP rats on a 22-hour fluid-deprivation schedule were given 2-hour daily access to a 10% (v/v) EtOH/3% (g/v) polycose solution and water. Average EtOH intake was 2.1 +/- 0.2 g/kg/2 hours, and water intake was 17.1 +/- 0.9 ml/2 hours. During the initial 15 minutes of the 2-hour session, RO19-4603, the imidazothienodiazepine partial inverse agonist reduced EtOH intake to 19% of control values at 0.04 mg/kg and completely suppressed drinking of the EtOH solution at 0.15 mg/kg. Twenty-four-hour postdrug administration, the 0.08-mg/kg dose of RO19-4603 completely suppressed drinking of the EtOH solution at the 60-minute interval, and the 0.15-mg/kg dose reduced intake to 20% of control levels at the 15-minute interval. FG 7142, the partial beta-carboline inverse agonist reduced EtOH drinking at the 60-minute interval with the 1-mg/kg dose, and the 16-mg/kg dose reduced water intake at the 15-minute interval. DMCM, the full beta-carboline inverse agonist, significantly reduced water intake at 15 minutes (4 and 8 mg/kg), and the same doses caused a substantial increase in EtOH drinking at the 120-minute interval. The anxiolytic agent bretazenil (16 and 32 mg/kg) increased EtOH consumption during the initial 15 minutes to 270% to 425% of control levels, and water intake increased by the end of the 2-hour session to as much as 210% of control following administration of the 32-mg/kg dose. These findings support existing evidence suggesting that BDZ receptor ligands may modify neuronal processes that mediate some reinforcing and/or aversive properties of alcohol. They further demonstrate a potential importance of the GABAA-BDZ receptor complex in mediating palatability- (environmentally) induced EtOH drinking even in rats selectively bred for low alcohol preference.


Subject(s)
Azepines/pharmacology , Ethanol/pharmacology , Receptors, GABA-A/drug effects , Analysis of Variance , Animals , Dose-Response Relationship, Drug , Glucans/pharmacology , Male , Rats , Time Factors
6.
Plant Physiol ; 107(2): 429-434, 1995 Feb.
Article in English | MEDLINE | ID: mdl-12228369

ABSTRACT

We report here an approach to metabolic engineering to alter the temperature characteristics of an enzyme pool based on the concept of thermal kinetics windows (TKWs), a useful indicator of enzyme performance. A chimeric cucumber NADH-hydroxypyruvate reductase (HPR) gene under the control of a cauliflower mosaic virus 35S promoter was constructed and introduced into the genome of tobacco (Tobacum tobacum). The root system of the R1 generation of the resultant transgenic plants expresses only the cucumber enzyme (the native tobacco HPR gene is light regulated and only found in the aerial portions of the plant). Enzyme isolated from the transgenic root tissues exhibits a TKW centered at 32.5[deg]C, characteristic of cucumber. The pool of HPR in the shoots, containing both tobacco and cucumber enzymes, exhibits a broad TKW consistent with an equal mix of the two forms. These data do not simply demonstrate that an introduced gene can be expressed in a transgenic plant but that the kinetics properties of the resultant enzyme are unaltered and when sufficient enzyme is produced the temperature characteristics of the total pool are altered. This suggests that the temperature characteristics of plant biochemical pathways can be broadened to suit changing thermal environments.

7.
Opt Lett ; 20(7): 707-9, 1995 Apr 01.
Article in English | MEDLINE | ID: mdl-19859304

ABSTRACT

We demonstrate the fabrication of a unique optical device, the single leakage-channel grating coupler, using solgel techniques. Design specifications are outlined to establish the material criteria for the sol-gel compositions. Material choice and preparation are described. We evaluate the characteristics and performance of the single leakage-channel grating coupler by comparing the predicted and the measured branching ratios. The branching ratio of the solution-derived device is within 3% of the theoretically predicted value.

8.
Appl Opt ; 34(27): 6180-6, 1995 Sep 20.
Article in English | MEDLINE | ID: mdl-21060461

ABSTRACT

We report a general approach to the design of broadband waveguide couplers. A double-parallel grating assembly is used to cancel the first chromatic order, and a proper choice of prism glass and base angle is made to compensate for the second chromatic order. The technique was applied to a Corning glass 7059 waveguide, and a spectral bandwidth of 70 nm was measured by the use of two complementary procedures.

9.
Psychopharmacology (Berl) ; 115(3): 325-31, 1994 Jul.
Article in English | MEDLINE | ID: mdl-7871072

ABSTRACT

The time course of the benzodiazepine (BDZ) inverse agonist RO19-4603 in antagonizing ethanol (EtOH) intake was investigated in alcohol-preferring (P) rats (n = 7) maintained on 24-h continuous free-choice access to EtOH (10% v/v), water, and food. After fluid intakes had stabilized over several weeks, animals were injected with Tween-80 vehicle solution or RO19-4603 (0.075, 0.150, and 0.30 mg/kg). EtOH and water intakes were determined at 8- and 24-h intervals. RO19-4603 caused a marked attenuation of EtOH drinking with each of the doses tested. EtOH intake during the 8-h following 0.075, 0.150, and 0.30 mg/kg RO19-4603 was decreased by approximately 36, 74, and 57%, respectively. Intakes during the 24-h interval were similar to the vehicle control condition. However, 32 h post-drug administration, EtOH intakes were reduced to approximately 27, 31, and 29% following the 0.075, 0.150 and 0.30 mg/kg doses, respectively. To further confirm the reliability of the RO19-4603 dose-response effect, and its selectivity for EtOH, the highest dose condition (0.30 mg/kg) was tested twice. The second 0.30 mg/kg dose condition exerted a profile of effects similar to the initial treatment; 8 h following administration, intake was decreased to 60% of the control level, and 32 h post-drug administration intake was decreased to approximately 46% of the controls. These decreases were evidently selective in comparison with water, since water drinking showed compensatory increases which paralleled the decreased EtOH consumption. Dose-response comparisons indicated that 0.150 mg/kg approaches the maximum effective dose, since the 0.30 mg/kg dose of RO19-4603 did not produce an additional decrease in EtOH intake.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Alcohol Deterrents/pharmacology , Alcohol Drinking/genetics , Alcohol Drinking/psychology , Azepines/pharmacology , GABA-A Receptor Agonists , Animals , Dose-Response Relationship, Drug , Drinking/drug effects , Female , Rats , Reward
10.
Mol Gen Genet ; 239(3): 425-34, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8316213

ABSTRACT

Tobacco plants were genetically transformed to generate antisense RNA from a gene construct comprised of a full-length cucumber NADH-dependent hydroxypyruvate reductase (HPR) cDNA placed in reverse orientation between the cauliflower mosaic virus 35S promoter and a nopaline synthase termination/polyadenylation signal sequence. In vivo accumulation of antisense HPR RNA within eight independent transgenic tobacco plants resulted in reductions of up to 50% in both native HPR activity and protein accumulation relative to untransformed tobacco plants (mean transgenote HPR activity = 67% wild type, mean transgenote HPR protein = 63% wild type). However, in contrast to previous reports describing antisense RNA effects in plants, production of the heterologous HPR antisense RNA did not systematically reduce levels of native tobacco HPR mRNA (mean transgenote HPR mRNA level = 135% wild type). Simple regression comparison of the steady-state levels of tobacco HPR mRNA to those of HPR antisense RNA showed a weak positive correlation (r value of 0.548, n = 9; n is wild type control plus eight independent transformants; significant at 85% confidence level), supporting the conclusion that native mRNA levels were not reduced within antisense plants. Although all transgenic antisense plants examined displayed an apparent reduction in both tobacco HPR protein and enzyme activity, there is no clear correlation between HPR activity and the amount of either sense (r = 0.267, n = 9) or antisense RNA (r = 0.175, n = 9). This compares to a weak positive correlation between HPR mRNA levels and the amount of HPR activity observed in wild-type SR1 tobacco plants (r = 0.603, n = 5).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Carbohydrate Dehydrogenases/biosynthesis , Carbohydrate Dehydrogenases/genetics , Genes, Plant , Plants, Genetically Modified/enzymology , RNA, Antisense/genetics , Cloning, Molecular , Enzyme Repression , Plant Proteins/analysis , Plant Proteins/genetics , Plants, Toxic , Plasmids , Poly A/analysis , Protein Biosynthesis , RNA Probes , RNA, Antisense/physiology , RNA, Messenger/analysis , Recombinant Fusion Proteins , Regression Analysis , Nicotiana/genetics , Transformation, Genetic
11.
Plant Physiol ; 102(1): 295-302, 1993 May.
Article in English | MEDLINE | ID: mdl-12231821

ABSTRACT

Analysis of the temperatures providing maximal photosystem II fluorescence reappearance following illumination and thermal kinetic windows (TKWs), obtained from the temperature characteristics of enzyme apparent Km values, have been proposed as indicators of the bounds of thermal stress in plants. In this study, we have evaluated the temperature optimum for the accumulation of the chlorophyll a/b light-harvesting complex of photosystem II (LHCP II), its mRNA, and the mRNA of the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) in cucumber (Cucumis sativus L. cv Ashley) as a broader measure of metabolism than that provided by either the fluorescence reappearance or TKWs. The TKW for cucumber is between 23.5 and 39[deg]C, with the minimum apparent Km occurring at 32.5[deg]C. The photosystem II variable fluorescence reappearance following illumination was maximal between 30 and 35[deg]C. Maximum synthesis of the LHCP II occurred at 30[deg] C. The light-induced accumulation of the LHCP II and the small subunit of Rubisco mRNAs showed similar temperature characteristics. Suboptimal temperatures delayed germination, altered cotyledonary soluble sugar content, and broadened the temperature range for chlorophyll accumulation. These results demonstrate an effect of seed reserve mobilization on the range of temperatures for chlorophyll accumulation, and suggest that metabolic temperature characteristics may be broadened by increasing available substrates for enzyme utilization. This study provides new information about the relationship between TKWs and cellular responses to temperature. In addition, the results suggest that the temperature range outside of which plants experience temperature stress is narrower than traditionally supposed.

12.
Proc Natl Acad Sci U S A ; 90(4): 1629-33, 1993 Feb 15.
Article in English | MEDLINE | ID: mdl-8434026

ABSTRACT

Transgenic tobacco plants that express a chimeric gene that encodes chloroplast-localized Cu/Zn superoxide dismutase (SOD) from pea have been developed. To investigate whether increased expression of chloroplast-targeted SOD could alter the resistance of photosynthesis to environmental stress, these plants were subjected to chilling temperatures and moderate (500 mumol of quanta per m2 per s) or high (1500 mumol of quanta per m2 per s) light intensity. During exposure to moderate stress, transgenic SOD plants retained rates of photosynthesis approximately 20% higher than untransformed tobacco plants, implicating active oxygen species in the reduction of photosynthesis during chilling. Unlike untransformed plants, transgenic SOD plants were capable of maintaining nearly 90% of their photosynthetic capacity (determined by their photosynthetic rates at 25 degrees C) following exposure to chilling at high light intensity for 4 hr. These plants also showed reduced levels of light-mediated cellular damage from the superoxide-generating herbicide methyl viologen. These results demonstrate that SOD is a critical component of the active-oxygen-scavenging system of plant chloroplasts and indicate that modification of SOD expression in transgenic plants can improve plant stress tolerance.


Subject(s)
Chloroplasts/enzymology , Isoenzymes/metabolism , Nicotiana/physiology , Plants, Toxic , Superoxide Dismutase/metabolism , Base Sequence , Chimera , Codon/genetics , Cold Temperature , Isoenzymes/genetics , Isoenzymes/isolation & purification , Light , Macromolecular Substances , Paraquat/pharmacology , Plants, Genetically Modified , Restriction Mapping , Superoxide Dismutase/genetics , Superoxide Dismutase/isolation & purification , Nicotiana/drug effects , Nicotiana/enzymology , Nicotiana/genetics
13.
Appl Opt ; 32(12): 2112-6, 1993 Apr 20.
Article in English | MEDLINE | ID: mdl-20820355

ABSTRACT

Analysis, fabrication, and characterization of variable groove depth planar waveguide grating couplers are presented. A formula is derived to describe the grating groove depth variation necessary to produce an outcoupled beam of arbitrary profile. A variable depth grating for producing a Gaussian beam profile is fabricated on a waveguide by ion-beam etching through a scanning slit apparatus. A photoresist grating placed on the waveguide provides a mask to define the grating etched onto the waveguide. The near-field irradiance of the outcoupled beam is measured and shown to approach a Gaussian profile.

14.
Appl Opt ; 32(24): 4522-8, 1993 Aug 20.
Article in English | MEDLINE | ID: mdl-20830114

ABSTRACT

We describe the modeling and fabrication of waveguide grating couplers with theoretical outcoupling efficiencies into a single diffracted order nearing 100%. Termed single leakage-channel grating couplers (or SLCGC's), these devices utilize a high-reflectivity dielectric stack to reflect the outcoupled beam diffracted toward the substrate and back up into the air region, where it constructively adds with the beam diffracted into the air region. Computer modeling shows that the branching ratio and the leakage rate can be independently controlled, and that the branching ratio is independent of grating depth and grating period. A SLCGC with a branching ratio of 97.1% is fabricated by the use of a combination of vacuum-evaporation and wet-chemical techniques.

15.
Plant Physiol ; 100(3): 1595-8, 1992 Nov.
Article in English | MEDLINE | ID: mdl-16653166

ABSTRACT

The activity of pea (Pisum sativum L.) Cu/Zn and Mn superoxide dismutase isoforms was evaluated across a range of temperatures from 10 to 45 degrees C. Maximal activity of the Cu/Zn and Mn superoxide dismutase isoforms was observed at 10 degrees C. Both cytoplasmic and chloroplast Cu/Zn superoxide dismutases exhibit a reduction in staining intensity with increasing temperatures. Mn superoxide dismutase, however, maintained a relatively constant staining intensity across the range of temperatures evaluated. An unrelated enzyme used as a control, malate dehydrogenase, exhibited the expected increase in staining activity with increasing temperatures. These results describe a unique response of a protection enzyme to temperature.

16.
Plant Physiol ; 100(1): 529-32, 1992 Sep.
Article in English | MEDLINE | ID: mdl-16652994

ABSTRACT

A new assay for measuring protein-methionine-S-oxide reductase is reported. The assay measures the conversion of N-(9-fluorenylmethoxycarbonyl)-methionine sulfoxide to N-(9-fluorenylmethoxycarbonyl)-methionine using fluorescence detection after high-performance liquid chromatography separation. Enzyme activity is linear over a 60-min period and the assay is sensitive enough to detect the consumption of only 1% of available substrate. Protein-methionine-S-oxide reductase activity was demonstrated in pea (Pisum sativum L.) chloroplasts, and enzyme levels in leaves of etiolated and light-grown seedlings were compared.

17.
Laryngoscope ; 102(7): 784-96, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1319531

ABSTRACT

Peripheral neural regeneration, over a 10-mm transectional gap, was determined in 70 rabbit buccal divisions of the facial nerve using two entubational systems (semipermeable and impermeable silicone chambers) prefilled with three natural occurring media (serum, blood, and saline) during a 5-week period. The number of myelinated axonal regenerates at the midchamber and at 2 mm in the distal transected neural stump were counted in each group and compared to pooled myelinated axonal counts in 9 normal rabbit buccal divisions of the facial nerve. Semipermeable porous chambers had an overall greater regeneration success rate (75% vs. 42.8%) and regained, on the average, a higher number of myelinated axons (51.4% vs. 26.1%) than silicone chamber regenerates. Semipermeable chambers prefilled with serum or blood had significantly higher regeneration success rates, myelinated axonal counts, and percentages of neural innervation of the distal transected neural stump. Both entubational systems produced similar axonal counts with intraluminal saline. The highest overall success rate (93.7%) and average number of myelinated axons per chamber (3072) were achieved in semipermeable chambers prefilled with serum. The greatest variability in myelinated axonal counts (0 to 3266 axons) and percentage of distal stump innervation (5.5% to 98.1%) was seen in silicone chambers filled with saline. The percentage of myelinated axons from the midchamber that innervated the distal stump was greater in semipermeable chambers with blood (73%) and serum (54%) than in silicone saline chambers (43%). On the average, the distal stumps from semipermeable chambers filled with serum (47%) and blood (33.5%) regained a higher percentage of normal myelinated axonal counts than silicone-saline chambers (12.5%). These results suggest that both the construction of entubational chamber and the intraluminal medium can have significant influence on neurite regeneration. Semipermeable chambers prefilled with serum have a strong neurite-promoting potential in peripheral neural regeneration of rabbit facial nerves.


Subject(s)
Facial Nerve/physiology , Nerve Regeneration/physiology , Analysis of Variance , Animals , Axons , Cell Count , Diffusion Chambers, Culture , Facial Nerve/cytology , Female , Nerve Fibers, Myelinated , Rabbits , Silicone Elastomers , Silicones
18.
Opt Lett ; 17(17): 1195-7, 1992 Sep 01.
Article in English | MEDLINE | ID: mdl-19798131

ABSTRACT

Periodically segmented planar waveguides are modeled by using the rigorous modal method of diffraction gratings. The radiation loss, effective index, and electric-field strength distribution are analyzed for different segment duty cycles. It is shown that except for the low radiation loss and possible presence of stop bands, a segmented waveguide behaves much like a uniform waveguide. The theoretical calculation confirms the low radiation loss observed experimentally.

19.
Appl Opt ; 31(21): 4190-7, 1992 Jul 20.
Article in English | MEDLINE | ID: mdl-20725402

ABSTRACT

An experimental and theoretical study of polarization properties of planar dielectric waveguide gratings operating at general (oblique) inicidence is reported. The radiation modes coupled out by a surface-relief waveguide grating, when the incident light is not normal to the grating rulings, are linearly polarized for TE excitation and are elliptically polarized for TM excitation. The polarization states of the radiation modes are determined primarily by the polarization state of the principal guided wave in the grating region and by the propagation directions of the radiation modes with respect to the plane of the principal guided wave. Experimental data and numerical results based on three physical models are presented.

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