Two waves of colonization straddling the K-Pg boundary formed the modern reef fish fauna.

Living reef fishes are one of the most diverse vertebrate assemblages on Earth. Despite its prominence and ecological importance, the origins and assembly of the reef fish fauna is poorly described. A patchy fossil record suggests that the major colonization of reef habitats must have occurred in the Late Cretaceous and early Palaeogene, with the earliest known modern fossil coral reef fish assemblage dated to 50 Ma. Using a phylogenetic approach, we analysed the early evolutionary dynamics of modern reef fishes. We find that reef lineages successively colonized reef habitats throughout the Late Cretaceous and early Palaeogene. Two waves of invasion were accompanied by increasing morphological convergence: one in the Late Cretaceous from 90 to 72 Ma and the other immediately following the end-Cretaceous mass extinction. The surge in reef invasions after the Cretaceous-Palaeogene boundary continued for 10 Myr, after which the pace of transitions to reef habitats slowed. Combined, these patterns match a classic niche-filling scenario: early transitions to reefs were made rapidly by morphologically distinct lineages and were followed by a decrease in the rate of invasions and eventual saturation of morphospace. Major alterations in reef composition, distribution and abundance, along with shifts in climate and oceanic currents, occurred during the Late Cretaceous and early Palaeogene interval. A causal mechanism between these changes and concurrent episodes of reef invasion remains obscure, but what is clear is that the broad framework of the modern reef fish fauna was in place within 10 Myr of the end-Cretaceous extinction.

External respiratory motion analysis and statistics for patients and volunteers.

We analyzed a large patient and volunteer study of external respiratory motion in order to develop a population database of respiratory information. We analyzed 120 lung, liver, and abdominal patients and 25 volunteers without lung disease to determine the extent of motion using the Varian Real-Time Position Management system. The volunteer respiratory motion was measured for both abdominal and thoracic placement of the RPM box. Evaluation of a subset of 55 patients demonstrates inter- and intrafraction variation over treatment. We also calculated baseline drift and duty cycle for patients and volunteers. The mean peak-to-peak amplitude (SD) for the patients was 1.0 (0.5) cm, and for the volunteers it was abdomen 0.8 (0.3) cm and thoracic 0.2 (0.2) cm. The mean period (SD) was 3.6 (1.0) s, 4.2 (1.1)s, and 4.1 (0.8) s, and the mean end exhale position (SD) was 60% (6), 58% (7), and 56% (7) for patient, volunteer abdomen, and volunteer thoracic, respectively. Baseline drift was greater than 0.5 cm for 40% of patients. We found statistically significant differences between the patient and volunteer groups. Peak-to-peak amplitude was significantly larger for patients than the volunteer abdominal measurement and the volunteer abdominal measurement is significantly larger than the volunteer thoracic measurement. The patient group also exhibited significantly larger baseline drift than the volunteer group. We also found that peak-to-peak amplitude was the most variable parameter for both intra- and interfraction motion. This database compilation can be used as a resource for expected motion when using external surrogates in radiotherapy applications.

Splitting of the distal median nerve.

Variations of the nerves of the forearm can lead to unexpected clinical findings during physical examination. Additionally, surgery in this region might encounter and potentially damage the nerve in such patients. Here, we present a case of a high split of the median nerve and discuss the findings of the case as well as review salient reports in the literature. Knowledge of such a variation can be important in patient diagnosis and treatment.

Clinical consequences of changing the sliding window IMRT dose rate.

Changing pulse repetition frequency or dose rate used for IMRT treatments can alter the number of monitor units (MUs) and the time required to deliver a plan. This work was done to develop a practical picture of the magnitude of these changes. We used Varian's Eclipse Treatment Planning System to calculate the number of MUs and beam-on times for a total of 40 different treatment plans across an array of common IMRT sites including prostate/pelvis, prostate bed, head and neck, and central nervous system cancers using dose rates of 300, 400 and 600 MU/min. In general, we observed a 4%-7% increase in the number of MUs delivered and a 10-40 second decrease in the beam-on time for each 100 MU/min of dose rate increase. The increase in the number of MUs resulted in a reduction of the "beam-on time saved". The exact magnitude of the changes depended on treatment site and planning target volume. These changes can lead to minor, but not negligible, concerns with respect to radiation protection and treatment planning. Although the number of MUs increased more rapidly for more complex treatment plans, the absolute beam-on time savings was greater for these plans because of the higher total number of MUs required to deliver them. We estimate that increasing the IMRT dose rate from 300 to 600 MU/min has the potential to add up to two treatment slots per day for each IMRT linear accelerator. These results will be of value to anyone considering general changes to IMRT dose rates within their clinic.

Phylogenetics of Archerfishes (Toxotidae) and Evolution of the Toxotid Shooting Apparatus.

Synopsis: Archerfishes (Toxotidae) are variously found in the fresh- and brackish-water environments of Asia Pacific and are well known for their ability to shoot water at terrestrial prey. These shots of water are intended to strike their prey and cause it to fall into the water for capture and consumption. While this behavior is well known, there are competing hypotheses (blowpipe vs. pressure tank hypothesis) of how archerfishes shoot and which oral structures are involved. Current understanding of archerfish shooting structures is largely based on two species, Toxotes chatareus and T. jaculatrix. We do not know if all archerfishes possess the same oral structures to shoot water, if anatomical variation is present within these oral structures, or how these features have evolved. Additionally, there is little information on the evolution of the Toxotidae as a whole, with all previous systematic works focusing on the interrelationships of the family. We first investigate the limits of archerfish species using new and previously published genetic data. Our analyses highlight that the current taxonomy of archerfishes does not conform to the relationships we recover. Toxotes mekongensis and T. siamensis are placed in the synonymy of T. chatareus, Toxotes carpentariensis is recognized as a species and removed from the synonymy of T. chatareus, and the genus Protoxotes is recognized for T. lorentzi based on the results of our analyses. We then take an integrative approach, using a combined analysis of discrete hard- and soft-tissue morphological characters with genetic data, to construct a phylogeny of the Toxotidae. Using the resulting phylogenetic hypothesis, we then characterize the evolutionary history and anatomical variation within the archerfishes. We discuss variation in the oral structures and the evolution of the mechanism with respect to the interrelationships of archerfishes, and find that the oral structures of archerfishes support the blowpipe hypothesis but soft-tissue oral structures may also play a role in shooting. Finally, by comparing the morphology of archerfishes to their sister group, we find that the Leptobramidae has relevant shooting features in the oral cavity, suggesting that some components of the archerfish shooting mechanism are examples of co-opted or exapted traits. Sinopsis Malay: Pelbagai jenis Ikan Sumpit (Toxotidae) dapat dijumpai di persekitaran air tawar dan payau di Asia Pasifik dan mereka terkenal dengan kebolehan mereka menembak air ke arah mangsa di darat. Tembakan air ini bertujuan untuk menyerang mangsa mereka dan menyebabkan mereka jatuh ke dalam air untuk ditangkap dan dimakan. Walaupun tingkah laku ini diketahui umum, terdapat hipotesis yang bersaing (hipotesis sumpitan vs. tangki tekanan) tentang cara ikan sumpit menembak dan struktur mulut yang terlibat. Pemahaman semasa tentang struktur menembak ikan sumpit adalah sebahagian besarnya berdasarkan dua spesies, Toxotes chatareus dan T. jaculatrix. Kami tidak pasti sama ada semua ikan sumpit mempunyai struktur mulut yang sama untuk menembak air, jika variasi anatomi terdapat dalam struktur mulut ini, atau bagaimana ciri-ciri ini telah berkembang. Tambahan pula, terdapat sedikit maklumat tentang evolusi Toxotidae secara keseluruhan, dengan semua penyelidikan sistematik sebelum ini memfokuskan pada hubungan saling keluarga. Kami pada mulanya mengkaji had spesies ikan sumpit ini menggunakan data genetik baharu dan yang diterbitkan sebelum ini. Analisis kami menunjukkan bahawa taksonomi semasa ikan sumpit tidak mematuhi hubungan yang kami perolehi. Toxotes mekongensis dan T. siamensis diletakkan bersama kesinoniman T. chatareus, Toxotes carpentariensis yang diiktiraf sebagai satu spesies dan dikeluarkan daripada kesinoniman T. chatareus, dan genus Protoxotes yang diiktiraf untuk T. lorentzi adalah berdasarkan hasil analisis kami. Kemudian kami mengambil pendekatan integratif, menggunakan analisis gabungan karakter morfologi tisu keras dan lembut diskret dengan data genetik, untuk membina filogeni Toxotidae. Menggunakan hipotesis filogenetik yang terhasil, kami kemudian mencirikan sejarah evolusi dan variasi anatomi dalam ikan sumpit. Kami membincangkan variasi dalam struktur mulut dan evolusi mekanisme berkenaan yang berkaitan dengan ikan sumpit, dan mendapati bahawa struktur mulut ikan sumpit menyokong hipotesis sumpitan tetapi struktur mulut tisu lembut juga mungkin memainkan peranan dalam cara menembak. Akhir sekali, dengan membandingkan morfologi ikan sumpit kepada kumpulan saudara mereka, kami mendapati bahawa Leptobramidae mempunyai ciri penangkapan yang relevan dalam rongga mulut mereka, menunjukkan bahawa beberapa komponen mekanisme penangkapan ikan sumpit merupakan contoh ciri-ciri yang diikut-sertakan atau diguna semula.

The productive conformation of arachidonic acid bound to prostaglandin synthase.

Prostaglandin H synthase-1 and -2 (PGHS-1 and -2) catalyze the committed step in prostaglandin synthesis and are targets for nonsteroidal anti-inflammatory drugs (NSAIDs) like aspirin. We have determined the structure of PGHS-1 at 3 angstrom resolution with arachidonic acid (AA) bound in a chemically productive conformation. The fatty acid adopts an extended L-shaped conformation that positions the 13proS hydrogen of AA for abstraction by tyrosine-385, the likely radical donor. A space also exists for oxygen addition on the antarafacial surface of the carbon in the 11-position (C-11). While this conformation allows endoperoxide formation between C-11 and C-9, it also implies that a subsequent conformational rearrangement must occur to allow formation of the C-8/C-12 bond and to position C-15 for attack by a second molecule of oxygen.

Radiative climate forcing by the mount pinatubo eruption.

Radiative flux anomalies derived from the National Aeronautics and Space Administration (NASA) spaceborne Earth Radiation Budget Experiment were used to determine the volcanic radiative forcing that followed the eruption of Mount Pinatubo in June 1991. They are the first unambiguous, direct measurements of large-scale volcanic forcing. The volcanic aerosols caused a strong cooling effect immediately; the amount of cooling increased through September 1991 as shortwave forcing increased relative to the longwave forcing. The primary effects of the aerosols were a direct increase in albedo over mostly clear areas and both direct and indirect increases in the albedo of cloudy areas.

The meteorological satellite: overview of 25 years of operation.

The first weather satellite was launched on 1 April 1960. In the 25 years since, weather satellites have contributed to improved weather analyses and forecasts worldwide. As a maturing component of a global observing system, the meteorological satellite promises even greater financial benefits and a higher quality of life to mankind.

The Franck-Condon principle and the sudden approximation.

The corrections to conventional Franck-Condon factors required by the assumption that an electronic transition takes place in a non-zero time t(0) are investigated using a theory based on the sudden approximation. An explicit expression using a harmonic oscillator model is given for the vibrational progression k'<--0'', where k', 0'' are the vibrational quantum numbers in the final and initial states respectively. The calculations for this case suggest that the effects of a non-zero t(0) will be very small for most molecular electronic spectra, but for certain long progressions the corrections become more significant and may in favourable cases be detectable, thus giving an experimental basis for the concept of a non-zero t(0) and an estimate of its size. Possible examples in the spectra of diatomic molecules where this effect may be found are discussed.

Apical-basolateral membrane asymmetry in canine cortical collecting tubule cells. Bradykinin, arginine vasopressin, prostaglandin E2 interrelationships.

The studies reported here were designed to determine if there is an apical-basolateral asymmetry to the release of prostaglandins by or to the biochemical effects of prostaglandins on the renal collecting tubule. Canine cortical collecting tubule (CCCT) cells were isolated by immunodissection and seeded at supraconfluent densities on Millipore filters. The resulting confluent monolayer of CCCT cells: (a) developed and maintained a transcellular potential difference of 1 mV (apical side negative); (b) exhibited a permeability to inulin that was the same as that obtained with similar monolayers of Madin-Darby canine kidney (MDCK) cells; and (c) released adenosine 3',5'-cyclicmonophosphate (cAMP) in response to arginine vasopressin (AVP) added to the basolateral but not the apical surface of the monolayer. These results indicate that confluent monolayers of CCCT cells on Millipore filters have characteristics of asymmetry that are seen with intact collecting tubules. Moreover, PGE2 added to either side of the CCCT cell monolayer crossed the monolayer at the same slow rate as inulin, which demonstrated the feasibility of examining the sidedness of the effects of and the release of PGE2. Although AVP caused cAMP release only when added to the basolateral side of CCCT cells, AVP caused the release of PGE2 when added to either the apical or basolateral surface. This result implies that there are at least two AVP receptor systems, one coupled to cAMP synthesis and one to PGE2 formation. In contrast to the results observed with AVP, bradykinin caused PGE2 release only when added to the apical surface of CCCT cells, which suggested that urinary but not blood borne kinins elicit PGE2 formation by the canine collecting tubule. PGE2 was released in comparable amounts on each side of the monolayer in response both to AVP and to bradykinin. High concentrations (greater than or equal to 10(-8) M) of PGE2 added to either side of the monolayer caused the release of cAMP. However, at concentrations (10(-10) - 10(-12) M) at which PGE2 had no independent effect on cAMP release, PGE2 inhibited the release of cAMP, which normally occurred in response to AVP. This inhibition occurred with PGE2 added to either the apical or basolateral surface of the CCCT cell monolayer. PGE2 (10(-11) M) also inhibited the AVP-induced accumulation of intracellular cAMP by CCCT cells seeded on culture dishes. This inhibition was only observed when the cells were preincubated with PGE2 for greater than or equal to 20 min. Our results are consistent with the concept that inhibiton by prostaglandins of the hydroosmotic effect of AVP is due to inhibition of AVP-induced cAMP production. This inhibition does not appear to involve a direct physical interaction of PGE2 with the AVP receptor which is coupled to adenylate cyclase, since CCCT cells must be preincubated with PGE2 for 20 min for the inhibition to be observed, and since PGE2 added to the apical surface of CCCT cells inhibits cAMP release in response to AVP acting from the basolateral surface.

Concentrations of prostaglandin endoperoxide synthase and prostaglandin I2 synthase in the endothelium and smooth muscle of bovine aorta.

Platelets adhere to the subendothelial layer of newly deendothelialized arteries. Attachment can be reduced with exogenous prostacyclin (PGI2). Thus, the subendothelium may be unable to produce sufficient PGI2 to prevent platelet adherence and subsequent platelet-platelet interaction. Consistent with this explanation are data from an earlier report (1977. Moncada S., A. G. Herman, E. A. Higgs, and J. R. Vane. Thromb. Res. 11:323-344) indicating that the smooth muscle layer of aorta has only 10-15% of the capacity of endothelial cells to synthesize PGI2. We have measured the concentrations of PGI2 synthase and prostaglandin endoperoxide (PGH) synthase in bovine aorta and obtained results quite different from those described in this earlier report. Tandem immunoradiometric assays for PGI2 synthase and PGH synthase antigens were used to quantitate these proteins in detergent-solubilized homogenates of endothelial cells and smooth muscle tissue prepared from 10 different bovine aorta. The concentrations of PGI2 synthase in endothelial cells and smooth muscle were found to be the same. However, the concentration of PGH synthase in endothelial cells averaged greater than 20 times that of smooth muscle. Results similar to those determined by immunoradiometric assay were also obtained when PGH synthase and PGI2 synthase catalytic activities were measured in preparations of endothelial and smooth muscle cells. Furthermore, when bovine aorta and renal arteries were subjected to immunocytofluorescence staining using monoclonal antibodies to PGI2 synthase, fluorescence staining of equivalent intensity was detected in both the endothelial cells and the smooth muscle. Moreover, the intensity of fluorescence was similar throughout cross-sections of vascular smooth muscle, indicating that there is no gradient in PGI2 synthase concentrations between the endothelium and adventitia. Our results indicate that the propensity of platelets to adhere to the subendothelium of deendothelialized arteries and form aggregates cannot be attributed simply to an inability of the denuded vasculature to produce PGI2 from PGH2, but may be a consequence of the low PGH synthase activity of smooth muscle. Consistent with this concept are the results of Eldor et al. (1981. J. Clin. Invest. 67:735-741) who reported that increases in PGH synthase activity are associated with formation of a nonthrombogenic neointima.

A1 and A2 adenosine receptors in rabbit cortical collecting tubule cells. Modulation of hormone-stimulated cAMP.

Adenosine analogs were used to investigate the cellular mechanisms by which adenosine may alter renal tubular function. Cultured rabbit cortical collecting tubule (RCCT) cells, isolated by immunodissection, were treated with 5'-N-ethylcarboxamideadenosine (NECA), N6-cyclohexyladenosine (CHA), and R-N6-phenylisopropyladenosine (PIA). All three analogs produced both dose-dependent inhibition and stimulation of RCCT cell cyclic AMP (cAMP) production. Stimulation of cAMP accumulation occurred at analog concentrations of 0.1 microM to 100 microM with the rank order of potency NECA greater than PIA greater than CHA. Inhibition occurred at concentrations of 1 nM to 1 microM with the rank order of potency CHA greater than PIA greater than NECA. These effects on cAMP production were inhibited by 1,3-diethyl-8-phenylxanthine and isobutylmethylxanthine. CHA (50 nM) blunted AVP- and isoproterenol-stimulated cAMP accumulation. This modulation of hormone-induced cAMP production was abolished by pretreatment of RCCT cells with pertussis toxin. Prostaglandin E2 production was unaffected by 0.1 mM CHA. These findings indicate the presence of both inhibitory (A1) and stimulatory (A2) receptors for adenosine in RCCT cells. Moreover, occupancy of the A1 receptor causes inhibition of both basal and hormone-stimulated cAMP formation through an action on the inhibitory guanine nucleotide-binding regulatory component, Ni, of the adenylate cyclase system.

Reduced platelet thromboxane formation in uremia. Evidence for a functional cyclooxygenase defect.

A qualitative platelet abnormality and a bleeding tendency are frequently associated with renal failure and uremia. We demonstrated previously that uremic patients display an abnormal platelet aggregation to arachidonic acid and reduced malondialdehyde production in response to thrombin and arachidonic acid. The objectives of this investigation were: (a) to compare platelet prostaglandin (PG) and thromboxane (TX) production in whole blood and in platelet-rich plasma (PRP) of 21 uremic patients and 22 healthy subjects; (b) to evaluate the concentration and activity of platelet PG- and TX-forming enzymes; (c) to assess the functional responsiveness of the platelet TXA(2)/PGH(2) receptor; (d) to explore the hemostatic consequences of partially reduced TXA(2) production.Platelet immunoreactive TXB(2) production during whole blood clotting was significantly reduced, by approximately 60%, in uremic patients as compared to age- and sex-matched controls. Exogenous thrombin (5-30 IU/ml) failed to restore normal TXB(2) production in uremic platelets. Uremic PRP produced comparable or slightly higher amounts of TXB(2) than normal PRP at arachidonate concentrations 0.25-1 mM. However, when exposed to substrate concentrations >2 mM, uremic PRP produced significantly less TXB(2) than normal PRP. To discriminate between reduced arachidonic acid oxygenation and altered endoperoxide metabolism, the time course of immunoreactive TXB(2) and PGE(2) production was measured during whole blood clotting. The synthesis and release of both cyclooxygenase-derived products was slower and significantly reduced, at all time intervals considered. Furthermore, PGI(2) production in whole blood, as reflected by serum immunoreactive 6-keto-PGF(1alpha) concentrations, was significantly reduced in uremic patients as compared with healthy subjects. PGH synthase levels, as determined by an immunoradiometric assay, were not significantly different in platelets from uremic patients as compared to control platelets. A single 40-mg dose of aspirin given to five healthy volunteers reduced their serum TXB(2) to levels found in uremic patients. This was associated with a significant increase of threshold aggregating concentrations of ADP and arachidonic acid and prolongation of bleeding time. Substantially similar threshold concentrations of U46619, a TXA(2) agonist, induced aggregation of normal and uremic platelets. Prostacyclin induced a significant elevation of uremic platelet cyclic AMP, which was suppressed by U46619, further suggesting normal responsiveness of the TXA(2)/PGH(2) receptor. WE CONCLUDE THAT: (a) an abnormality of platelet arachidonic acid metabolism exists in uremia, leading to a reduced TXA(2) production; (b) the characteristics of this abnormality are consistent with a functional cyclooxygenase defect; (c) reduced TXA(2) production may partially explain the previously described abnormality of platelet function in uremia.

Prostaglandin and thromboxane biosynthesis.

We describe the enzymological regulation of the formation of prostaglandin (PG) D2, PGE2, PGF2 alpha, 9 alpha, 11 beta-PGF2, PGI2 (prostacyclin), and thromboxane (Tx) A2 from arachidonic acid. We discuss the three major steps in prostanoid formation: (a) arachidonate mobilization from monophosphatidylinositol involving phospholipase C, diglyceride lipase, and monoglyceride lipase and from phosphatidylcholine involving phospholipase A2; (b) formation of prostaglandin endoperoxides (PGG2 and PGH2) catalyzed by the cyclooxygenase and peroxidase activities of PGH synthase; and (c) synthesis of PGD2, PGE2, PGF2 alpha, 9 alpha, 11 beta-PGF2, PGI2, and TxA2 from PGH2. We also include information on the roles of aspirin and other nonsteroidal anti-inflammatory drugs, dexamethasone and other anti-inflammatory steroids, platelet-derived growth factor (PDGF), and interleukin-1 in prostaglandin metabolism.

Genetic analysis of phototactic behavior in Drosophila simulans.

Phototaxis mazes have been employed to select photopositive and photonegative strains of Drosophila simulans. The results suggest that phototactic behavior in D. simulans, as in other Drosophila species, is a polygenic trait. Hybridization using divergent strains revealed that the genes controlling negative phototactic behavior in D. simulans are autosomal, as opposed to D. melanogaster in which negative phototactic behavior is known to be very strongly sex-linked.

Rapid induction of prostaglandin endoperoxide synthase in rat preovulatory follicles by luteinizing hormone and cAMP is blocked by inhibitors of transcription and translation.

Prostaglandin endoperoxide synthase (PGS) catalyzes the rate-limiting step in the synthesis of prostaglandins E and F2 alpha that are obligatory for ovulation. To understand the molecular mechanisms by which LH regulates the induction of PGS in rat preovulatory (PO) follicles, we established an in vitro system which mimics in vivo induction of the enzyme. We show that the rapid increase in PGS enzyme: 1) is stimulated by LH, FSH, and forskolin (cAMP) in a time- and dose-dependent manner that is distinct from changes in steroidogenic enzymes analyzed in the same follicles; 2) is unaltered by end products (PGE and PGF2 alpha) of the reaction or inhibitors (indomethacin) of enzyme activity; 3) is blocked by inhibitors of transcription (alpha-amanitin) and translation (cycloheximide) at a step distal to production of cAMP and activation of A-kinase. Analyses of PGS mRNA by Northern blots using a mouse PGS cDNA probe revealed a PGS transcript of 2.8 kilobases that was present but in low abundance in PO follicles and decreased rapidly (1-4 h) as a consequence of LH/human CG stimulation. This hormone-induced decrease in PGS mRNA appeared to be transient because PGS transcripts were present in corpora lutea at a level similar to that in PO follicles. These results raise the possibility that the marked increase in PGS enzyme in granulosa cells of PO follicles that occurs as a consequence of the LH/human CG surge may not involve a cAMP regulated increase in transcription of the PGS gene itself. Or, if increased transcription of PGS mRNA does occur, it is rapid and coupled with cotranslational degradation of the mRNA. Alternatively, transcriptional (alpha-amanitin-sensitive) regulation of a separate gene may be obligatory for increased translation of PGS mRNA or posttranslational modification (stabilization?) of the enzyme. In summary, the LH-stimulated appearance of PGS in granulosa cells of PO follicles before ovulation is mediated by cAMP in a complex manner involving transcriptional regulation (PGS gene?) and translational control of PGS mRNA. The transient appearance of the PGS enzyme represents a unique pattern of response by granulosa cells of PO follicles to LH/cAMP and thereby may involve novel intracellular factors and regulatory processes.

Disinfection of dairy and animal farm wastewater with radiofrequency power.

Radiofrequency (RF) power was investigated as a new, physical (nonchemical), thermal process to disinfect wastewater from dairy and animal facilities. Samples (n = 38) from 8 dairy, 2 calf, and 3 swine facilities in California were collected over a 3-yr period and characterized for their dielectric properties, chemical composition, and suitability for thermal processing using RF power. To establish efficacy for disinfection, selected samples were inoculated with high levels (10(6) to 10(9) cfu/mL) of bacterial pathogens such as Salmonella sp., Escherichia coli O157:H7, and Mycobacterium avium ssp. paratuberculosis and processed with an RF prototype system. The capabilities of RF power as a method for thermal disinfection of wastewater were demonstrated when bacteria pathogens were completely and rapidly (<1 min) inactivated when temperatures of 60 to 65 degrees C were achieved. Furthermore, RF technology can be used for large-scale, batch or continuous and portable applications, allowing significant improvements in energy-use efficiencies compared with conventional thermal (surface heating) technologies. Therefore, RF power has potential as an alternative to disinfect dairy/animal farm wastewater before recycling.

Involvement of prostaglandin endoperoxide H synthase-2 in osteoclast-like cell formation induced by interleukin-1 beta.

Interleukin-1 beta (IL-1 beta) stimulates osteoclast-like cell formation via prostaglandin E2 (PGE2) production. However, the regulatory mechanism for the production of PGE2 in bone cells is still unclear. Recently, it has been shown that two prostaglandin endoperoxide H synthase (PGHS) isozymes exist, termed PGSH-1 and PGHS-2. We report here that IL-1 beta induces PGE2 production in bone marrow culture induced by a PGHS-2-dependent mechanism. IL-1 beta stimulated the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells (MNC) and the production of PGE2 in mouse bone marrow cultures. The dose response curves for the indomethacin inhibition of TRAP-positive MNC formation and PGE2 production were nearly identical. Cycloheximide (CHX) suppressed IL-1 beta-induced PGE2 production, suggesting that the production of PGE2 induced by IL-1 beta required de novo protein synthesis. Northern blot analysis determined that IL-1 beta induced PGHS-2 expression by 30 minutes and mRNA levels were maximal by 1-2 h. Cycloheximide potentiated the accumulation of PGHS-2 mRNA linearly up to 8 h. Dexamethasone, an inhibitor of the induction of PGHS-2, inhibited IL-1 beta-induced PGHS-2 mRNA expression and also suppressed IL-1 beta-stimulated formation of TRAP-positive MNC. Furthermore NS-398, as a selective PGHS-2 inhibitor, completely inhibited IL-1 beta-induced TRAP-positive MNC formation. Moreover, IL-1 beta-induced PGHS-2 mRNA expression and formation of TRAP-positive MNC were inhibited by calphostin C, a selective inhibitor of protein kinase C (PKC). These results indicate that IL-1 beta-induced formation of osteoclast-like cells requires PKC activation, induction of PGHS-2, and subsequent prostaglandin synthesis by this enzyme.

Prostaglandin endoperoxide synthase in rat ovarian follicles: content, cellular distribution, and evidence for hormonal induction preceding ovulation.

These studies were undertaken to determine if the content of prostaglandin endoperoxide (PGH) synthase (PGS) was regulated in rat ovarian follicles in a time-, tissue-, and dose-dependent manner. For quantitation and localization of the enzyme by immunoblot and immunofluorescent analyses, respectively, a polyclonal antibody to highly purified (95%) ovine seminal vesicle PGS [mol wt, (Mr), 72,000] was generated in a rabbit, and an immunoglobulin G fraction of the antiserum was purified by elution from a PGS affinity resin. Soluble cell extracts were prepared from: 1) small antral (SA) and preovulatory (PO) rat follicles before and at selected time intervals after exposure to increasing doses (0.25-10.0 IU) of hCG, 2) granulosa and thecal cells of these same follicles, and 3) granulosa cells of hypophysectomized (H) rats before and after treatment with estradiol (HE), estradiol and FSH (HEF), and 10 IU hCG. Immunoblot analyses demonstrated that the content of PGS (Mr, 72,000) was low (negligible) in granulosa and thecal cells of SA and PO follicles, was induced preferentially (approximately 15-fold) in granulosa cells between 1 and 7 h after hCG treatment (0.5, 2.0, or 10 IU), and declined between 12-24 h after administration of 10 IU hCG, reaching undetectable amounts in corpora lutea isolated 48 h after hCG treatment. PGS (Mr, 72,000) was also induced by 10 IU hCG in granulosa cells of HEF rats, but was low in granulosa cells of H, HE, and HEF rats. In contrast, prostacyclin synthase was present in granulosa cells of preantral (H and HE rats), SA, and PO follicles, was not induced by hCG, and was highest in thecal cells. Immunofluorescent analyses confirmed both the tissue-specific localization and induction of PGS in granulosa cells of rat PO follicles treated with 10 IU hCG and the subcellular fractionation analyses showing that the PGS that was induced by hCG was localized primarily to a membrane (plasma membrane?) fraction of granulosa cells. Immunofluorescent data also demonstrated immunoreactive PGS in the vascular tissue of the rat corpus luteum but not in the luteal cells. Results of these studies document unequivocally that the synthesis of prostaglandins that is increased by LH/hCG in rats preceding ovulation is associated with an increased PGS content, that induction of the induced enzyme is transient, and that the enzyme is primarily localized to granulosa cell membrane fractions.

Cloning of an adenosine A1 receptor-encoding gene from rabbit.

A partial cDNA encoding the A1 adenosine receptor (A1AR), which lacks nucleotides coding for the first 74 amino acids (aa), was isolated from a rabbit kidney cDNA library. The missing 5' end sequence was obtained from an overlapping rabbit genomic clone which was found to contain the flanking 5' untranslated region (5'UTR), the first exon and part of the first intron. Together, the cDNA and genomic clones provide the entire open reading frame (ORF) encoding rabbit A1AR. The deduced aa sequence is highly homologous to the canine, rat and bovine A1ARs. These data also indicate that the A1AR gene belongs to the family of intron-containing G-protein-linked receptor genes.