Microseparation chips for performing multienzymatic dehydrogenase/oxidase assays: simultaneous electrochemical measurement of ethanol and glucose

This report describes a new "lab-on-a-chip" protocol integrating on-line precolumn biocatalytic reactions of multiple (oxidase and dehydrogenase) enzymes and substrates with effective capillary electrophoresis microseparations and amperometric detection. The operation of the new oxidase/dehydrogenase reaction/separation microchip is illustrated for the simultaneous measurement of glucose and ethanol in connection to the corresponding glucose oxidase and alcohol dehydrogenase reactions, respectively. The enzymatic reactions generate hydrogen peroxide and NADH species that are separated (on the basis of their different charges) and detected amperometrically at the end-column thick-film detector. A driving voltage of 2000 V results in peroxide and NADH migration times of 74 and 230 s, respectively. Operating the gold-coated carbon detector at +1.0 V allows simultaneous anodic detection of both reaction products. Factors influencing the reaction, separation, and detection processes are examined and optimized. The applicability of the new multienzyme assay to wine samples is illustrated.

[The efficiency of algae removal from drinking water by ferrate]

This paper studied the efficiency of algae removal by ferrate from two kinds of raw water which were collected from Donghu and Tiegang reservoir respectively. The experimental results showed that the removal efficiency of algae reached about 95% only through PAC coagulation when the raw water was extracted from Donghu reservoir in which most of algae was Chlorella. But dealing with Tiegang raw water in which the majority of algae were Oscillatoria, terrate was used as pre-oxidant coupling with PAC coagulation not only using PAC to flocculate and the efficiency of algae removal could be up to 97.85%. However this treatment method using ferrate as pre-oxidant overmatched the traditional method prechlorination for algae removal.

Acute effects of H-7 on ciliary epithelium and corneal endothelium in monkey eyes

PURPOSE

Topical or intracameral administration of H-7 doubles outflow facility and reduces intraocular pressure in cynomolgus monkeys, by relaxing and expanding the trabecular meshwork (TM) and Schlemm's canal (SC). Since H-7 may have anti-glaucoma potential, we determined its effects on the corneal endothelium and ciliary epithelium for safety considerations.

METHODS

Following topical H-7, aqueous humor flow (AHF), corneal endothelial transfer coefficient (k(a)) and anterior chamber (AC) entry of i.v. fluorescein were measured by fluorophotometry; AC aqueous protein concentration ([Protein](AC)) was determined by Lowry assay; and corneal thickness and endothelial cell density and morphology were measured by ultrasonic pachymetry and specular microscopy respectively. Following intracameral H-7, specular and/or light and electron microscopy of the corneal endothelium or ciliary epithelium were performed.

RESULTS

Following unilateral topical H-7: (1) AHF and k(a) were essentially unchanged at 0.5--3.0, 3.5--6.0, and 0.5--6.0 hr, with an insignificant increase from 0.5--1.5 hr; (2) [Protein]( AC) was insignificantly increased at 1-1.5 hr but had returned to baseline by 2.5 hr; (3) entry of i.v. fluorescein into aqueous or cornea was modestly and transiently increased; (4) the central cornea thickened significantly at 1--2.5 hr, gradually returning to baseline 2.5 hr after H-7, while peripheral corneal thickness was less affected; (5) corneal endothelial cell borders became indistinct by 1 hr, but cell morphology was recovering by 3--5 hr and had completely returned to normal by 24 hr; (6) corneal endothelial cell density was unchanged at 5--24 hr. Following intracameral H-7, no significant changes were observed in corneal endothelial cell density or morphology by specular microscopy, nor in corneal endothelial or ciliary epithelial morphology by light and electron microscopy.

CONCLUSIONS

A facility-effective intracameral dose of H-7 had no discernible structural effect on the corneal endothelium or ciliary epithelium. It is not yet clear whether carefully chosen topical doses of H-7 or analogues can enhance outflow facility without meaningfully affecting the cornea and ciliary processes.

Hepatitis C virus envelope protein E2 does not inhibit PKR by simple competition with autophosphorylation sites in the RNA-binding domain

Double-stranded-RNA (dsRNA)-dependent protein kinase PKR is induced by interferon and activated upon autophosphorylation. We previously identified four autophosphorylated amino acids and elucidated their participation in PKR activation. Three of these sites are in the central region of the protein, and one is in the kinase domain. Here we describe the identification of four additional autophosphorylated amino acids in the spacer region that separates the two dsRNA-binding motifs in the RNA-binding domain. Eight amino acids, including these autophosphorylation sites, are duplicated in hepatitis C virus (HCV) envelope protein E2. This region of E2 is required for its inhibition of PKR although the mechanism of inhibition is not known. Replacement of all four of these residues in PKR with alanines did not dramatically affect kinase activity in vitro or in yeast Saccharomyces cerevisiae. However, when coupled with mutations of serine 242 and threonines 255 and 258 in the central region, these mutations increased PKR protein expression in mammalian cells, consistent with diminished kinase activity. A synthetic peptide corresponding to this region of PKR was phosphorylated in vitro by PKR, but phosphorylation was strongly inhibited after PKR was preincubated with HCV E2. Another synthetic peptide, corresponding to the central region of PKR and containing serine 242, was also phosphorylated by active PKR, but E2 did not inhibit this peptide as efficiently. Neither of the PKR peptides was able to disrupt the HCV E2-PKR interaction. Taken together, these results show that PKR is autophosphorylated on serine 83 and threonines 88, 89, and 90, that this autophosphorylation may enhance kinase activation, and that the inhibition of PKR by HCV E2 is not solely due to duplication of and competition with these autophosphorylation sites.

Hierarchical organization of the human auditory cortex revealed by functional magnetic resonance imaging

The concept of hierarchical processing--that the sensory world is broken down into basic features later integrated into more complex stimulus preferences--originated from investigations of the visual cortex. Recent studies of the auditory cortex in nonhuman primates revealed a comparable architecture, in which core areas, receiving direct input from the thalamus, in turn, provide input to a surrounding belt. Here functional magnetic resonance imaging (fMRI) shows that the human auditory cortex displays a similar hierarchical organization: pure tones (PTs) activate primarily the core, whereas belt areas prefer complex sounds, such as narrow-band noise bursts.

Micromachined separation chips with a precolumn reactor and end-column electrochemical detector

Glass microchips, integrating chemical derivatization reactions, electrophoretic separations, and amperometric detection, have been developed. The performance of the new integrated microfabricated devices is demonstrated for rapid on-chip measurements of amino acids utilizing precolumn reactions of amino acids with o-phthaldialdehyde/2-mercaptoethanol to generate electroactive derivatives that are separated electrophoretically and detected at the end-column electrochemical detector. The influence of the sample/reagent mixing ratio, reagent concentrations, driving voltage, detection potential, and other variables is explored. The integrated microsystem offers a rapid (6 min) simultaneous measurements of eight amino acids, down to approximately 2.5 x 10(-6) M (5 fmol) level, with linearity up to the 2 x 10(-4) M level examined, and good reproducibility (RSD = 2.2-2.7%). A step of the driving voltage is used for decreasing the migration time of late-eluting components and reducing the overall analysis time. The integrated microfabricated device expands the scope of on-chip electrochemical detection to nonelectroactive analytes and holds promise of being a powerful analytical tool.

ML-7, chelerythrine and phorbol ester increase outflow facility in the monkey Eye

Baseline or post-drug outflow facility was measured by two-level constant pressure perfusion of the anterior chamber (AC). The AC of one eye of cynomolgus monkeys was exchanged with the myosin light chain kinase (MLCK) inhibitor ML-7, the protein kinase (PK) C inhibitor chelerythrine (CHEL), or the PKC activator phorbol myristate acetate (PMA), followed by continuous AC infusion of the drug. The opposite eye similarly received the corresponding vehicle solution. The facility-effectiveness of subthreshold doses of ML-7 or CHEL + a subthreshold dose of the serine-threonine kinase inhibitor H-7, and of facility-effective doses of CHEL + a subthreshold or effective dose of PMA, were also determined. In 45 min post-exchange perfusions, 100 and 500 microM ML-7 increased outflow facility by 32 and 76%, while 100 and 500 microM CHEL increased facility by 68 and 101%, respectively, adjusted for baseline and contralateral control eye resistance washout. In 90 min post-exchange perfusions, 100 microM ML-7 or CHEL time-dependently increased outflow facility by 23, 49 and 69%, or by 44, 108 and 125% in the first, second and third 30 min periods, respectively. At 50 microM, ML-7 was ineffective, but CHEL increased outflow facility by 36% in the third 30 min period. Ten microM H-7 potentiated the outflow facility effect of 50 microM ML-7 or 20 microM CHEL by 36 and 28%, respectively, in the second 30 min period, and that of 50 microM CHEL by 44% in the overall 60 min post-exchange perfusion, compared to the H-7 only-treated contralateral eye. Ten, 50 or 100 n M PMA dose-dependently increased outflow facility by 23, 62 or 174%. Ten n M PMA + 50 microM CHEL did not induce any additional significant changes in outflow facility compared to 50 n M CHEL alone, while the effect of 50 n M PMA and 100 microM CHEL together was 63% more than that of 100 microM CHEL alone. In conclusion, ML-7/CHEL may increase outflow facility by a cytoskeletal mechanism. Separate or combined treatment with CHEL and PMA increases outflow facility, suggesting that PKC inhibition may not be involved in the facility-increase with either drug.

Mechanisms and streams for processing of "what" and "where" in auditory cortex

The functional specialization and hierarchical organization of multiple areas in rhesus monkey auditory cortex were examined with various types of complex sounds. Neurons in the lateral belt areas of the superior temporal gyrus were tuned to the best center frequency and bandwidth of band-passed noise bursts. They were also selective for the rate and direction of linear frequency modulated sweeps. Many neurons showed a preference for a limited number of species-specific vocalizations ("monkey calls"). These response selectivities can be explained by nonlinear spectral and temporal integration mechanisms. In a separate series of experiments, monkey calls were presented at different spatial locations, and the tuning of lateral belt neurons to monkey calls and spatial location was determined. Of the three belt areas the anterolateral area shows the highest degree of specificity for monkey calls, whereas neurons in the caudolateral area display the greatest spatial selectivity. We conclude that the cortical auditory system of primates is divided into at least two processing streams, a spatial stream that originates in the caudal part of the superior temporal gyrus and projects to the parietal cortex, and a pattern or object stream originating in the more anterior portions of the lateral belt. A similar division of labor can be seen in human auditory cortex by using functional neuroimaging.

[Attenuation of hyperacute rejection from xenograft by reseeding of endothelial cell]

The potential solution to palliate the critical shortage of suitable donor organs for transplantation may be xenogenic transplantation. However, hyperacute rejection (HAR) after xenotransplantation is the main problem in this process. Since the vascular endothelial cell of donor organ is the primary target cell in rejection, the replacement of endothelium in donor organs with endothelial cell from recipients themselves may be beneficial to the prevention of HAR. Discordant xenotransplantation model (guinea pig-to-rat) was adopted in this study. Firstly, endothelial cell from rat abdominal aorta was separated and cultured. Secondly, the guinea pig abdominal aorta of which the endothelium had been removed was cultured with the suspension containing rat endothelial cells (4 x 10(6)/ml). The viability of cultured vessel was assessed using light microscopy and transmission electron microscopy. The guinea pig vessel reseeded with rat endothelial cell was then examined by immuno-fluorescence staining assay to find out whether IgM and C3 in rat serum were bound to it after preincubation with rat serum. It was found that rat endothelial cells grew into the monolayer endothelium on the inner surface of guinea pig vessel with previous endothelial loss. IgM and C3 in rat serum did not deposit along the new endothelium of guinea pig vessel in the treated group as shown by immuno-fluorescence microscopy, whereas possive results were observed in the untreated normal guinea pig aorta. These findings indicate that donor vessel reseeded with endothelial cell from recipients undergoes less severe rejection and this technique may be very useful for the attenuation of HAR.

H-7 effects on the structure and fluid conductance of monkey trabecular meshwork

OBJECTIVE

To determine the effects of H-7 (1-[5-isoquinoline sulfonyl]-2-methyl piperazine) on the structure and fluid conductance of the trabecular meshwork of live cynomolgus monkeys.

METHODS

Fluid outflow was measured by constant pressure perfusion of the anterior chamber with cationized and noncationized gold solution with or without H-7 in opposite eyes. The eyes were fixed by infusing Ito solution and enucleated. Anterior segments were cut into 4 sections, fixed in immersion solution, and embedded in epoxy resin-812. Trabecular meshwork morphologic features were studied by light and electron microscopy.

RESULTS

H-7 affected trabecular meshwork organization and increased fluid outflow. H-7 expanded the intercellular spaces in the juxtacanalicular meshwork, accompanied by removal of extracellular material. The inner wall cells of the Schlemm canal became highly extended, yet cell-cell junctions were maintained. Colloidal gold particles were detected only in limited areas along the subcanalicular region in control eyes; after H-7 treatment, gold was widely seen along the entire inner canal wall. Most inner wall cells in H-7-treated eyes, but only few cells in control eyes, contained gold-loaded vesicles.

CONCLUSION

H-7 inhibits cell contractility, leading to "relaxation" of the trabecular outflow pathway, expanding the draining surface, and permitting more extensive flow through the meshwork.

CLINICAL RELEVANCE

By inhibiting cellular contractility and relaxing the trabecular meshwork, the protein kinase inhibitor H-7 increases outflow facility and reduces intraocular pressure and thus has potential as an ocular hypotensive antiglaucoma medication. Arch Ophthalmol. 2000;118:955-962

Lab-on-a-Cable for electrochemical monitoring of phenolic contaminants

The "Lab-on-a-Cable" concept, based on scaling down an electrochemical flow system to a cable platform, is described. The system integrates the analyte collection and the sample handling, with the electrochemical detection of the reaction product in a sealed cylindrical unit, connected to a long shielded cable. An enzymatic assay, involving collection of a phenolic substrate, its mixing with an internally delivered tyrosinase solution, and amperometric detection of the liberated quinone product, is used for illustrating the operation of the flow probe and demonstrating its advantages over remote phenol sensors. The internal buffer solution ensures independence of sample conditions such as pH, ionic strength, or natural conditions, that commonly influences the performance of remote sensors. The "built-in" flow pulsation of the integrated micropump is exploited for a sensitive hydrodynamic-modulation voltammetric detection of hydrazine and peroxide pollutants.

Latrunculins' effects on intraocular pressure, aqueous humor flow, and corneal endothelium

PURPOSE

To determine the effects of latrunculin (LAT)-A or -B on intraocular pressure (IOP), aqueous humor flow (AHF), anterior chamber (AC) protein concentration ([protein]AC), corneal endothelial permeability and morphology, and corneal thickness in living cynomolgus monkeys.

METHODS

Topical LAT-A or LAT-B was administered to one eye, and vehicle to the other. IOP was measured by Goldmann tonometry, AHF and corneal endothelium transfer coefficient (ka) by fluorophotometry, [protein]Ac by Lowry assay, corneal endothelial cell morphology by specular microphotography, and corneal thickness by ultrasound pachymetry.

RESULTS

LAT-A began to lower IOP at 6 hours and maximally reduced IOP by 4.6 mm Hg at 9 hours. LAT-B lowered IOP within 1 hour and maximally reduced IOP by 3.1 mm Hg at 6 hours. LAT-A increased AHF by 87% for 3 hours and increased ka by 94% over 6 hours; LAT-B increased ka by 39% over 6 hours without affecting AHF. LAT-A increased IV fluorescein entry into the cornea approximately 10 fold, but did not affect IV fluorescein entry into the AC. LAT-A increased [protein]AC by 25% at 2 hours but not 5.5 hours. LAT-B variably and insignificantly increased [protein]AC: at 1 hour but not at 6.5 hours. LAT-A induced extensive corneal endothelial pseudoguttata within 1 hour, with normal cell counts by 7 days. LAT-B increased central corneal thickness maximally by 47 microm at 3.5 hours.

CONCLUSIONS

LAT-A and -B significantly reduced IOP and were consistent in their facility-increasing effect, indicating that pharmacologic disorganization of the actin cytoskeleton in the trabecular meshwork by latrunculins may be a useful antiglaucoma strategy. However, effects on corneal endothelium or ciliary epithelium are a potential safety issue.

Microfabricated electrophoresis chips for simultaneous bioassays of glucose, uric acid, ascorbic acid, and acetaminophen

A micromachined capillary electrophoresis chip is described for simultaneous measurements of glucose, ascorbic acid, acetaminophen, and uric acid. Fluid control is used to mix the sample and enzyme glucose oxidase (GOx). The enzymatic reaction, a catalyzed aerobic oxidation of glucose to gluconic acid and hydrogen peroxide, occurs along the separation channel. The enzymatically liberated neutral peroxide species is separated electrophoretically from the anionic uric and ascorbic acids in the separation/reaction channel. The three oxidizable species are detected at the downstream gold-coated thick-film amperometric detector at different migration times. Glucose can be detected within less than 100 s, and detection of all electroactive constituents is carried out within 4 min. Measurements of glucose in the presence of acetaminophen, a neutral compound, are accomplished by comparing the responses in the presence and absence of GOx in the running buffer. The reproducibility of the on-chip glucose measurements is improved greatly by using uric acid as an internal standard. Factors influencing the performance, including the GOx concentration, field strength, and detection potential, are optimized. Such coupling of enzymatic assays with electrophoretic separations on a microchip platform holds great promise for rapid testing of metabolites (such as glucose or lactate), as well as for the introduction of high-speed clinical microanalyzers based on multichannel chips.

Functional role of cyclin A on induction of fibroblast apoptosis due to ligation of CD44 matrix receptor by anti-CD44 antibody

Ligation of cell surface matrix adhesion receptors such as integrins can increase expression of specific cell cycle regulatory proteins such as cyclin A, thereby regulating cell cycle progression. Disruption of cell surface matrix receptor interaction with the extracellular matrix can trigger apoptosis. Induction of apoptosis has been linked to unscheduled up-regulation of cyclin A and activation of cyclin-A-associated dependent kinase 2 activity due to cleavage of cyclin-dependent kinase inhibitors by caspases. We have found that ligation of the cell surface matrix adhesion receptor CD44 by anti-CD44 antibody induces cell detachment and triggers apoptosis. In this report we show that ligation of CD44 by anti-CD44 antibody increases the expression of cyclin A protein prior to activation of caspase-3-like activity and morphological changes of apoptosis. Down-regulation of cyclin A protein levels by cyclin A antisense oligonucleotides dramatically decreased fibroblast apoptosis in response to anti-CD44 antibody. These data identify an important functional role of cyclin A in the induction of fibroblast apoptosis due to the ligation of the cell surface adhesion receptor CD44 by anti-CD44 antibody.

Renal interstitial Ca(2+)

Renal interstitial fluid Ca(2+) concentration ([Ca(2+)](isf)) was measured in anesthetized Wistar rats by using in situ microdialysis. During perfusion of 20 cm of the proximal small intestine with Ca(2+)-free buffer, renal [Ca(2+)](isf) was 1.63 +/- 0.19 mmol/l in the cortex (n = 6) and 1.93 +/- 0.12 mmol/l in the medulla (n = 5, P = 0.223). When Ca(2+) in the intestinal lumen was increased to 3 mmol/l, no change was seen in total or ionized serum Ca(2+) (S(Ca)), urinary Ca(2+) excretion (U(Ca)), or Ca(2+) in a microdialysate of the kidney cortex. Increasing intestinal Ca(2+) further, to 6 mmol/l, was without effect on S(Ca) but significantly increased U(Ca) by 38% and microdialysate Ca(2+) by 36% (1.25 +/- 0.0.09 vs. 1.70 +/- 0. 14 mmol/l, n = 4, P < 0.05). Intravenous infusion of 28 ng. kg(-1). min(-1) of parathyroid hormone for 1 h during perfusion of the intestinal lumen with 1 mmol/ Ca(2+)caused a 7-10% rise in S(Ca), a 40% fall in U(Ca), and a 32% increase in microdialysate Ca(2+) (1.32 +/- 0.13 vs. 1.74 +/- 0.13 mmol/l, n = 6, P < 0.05). Interlobar arteries with a mean diameter of 120 microm were studied by using a wire myograph to determine whether changes in extracellular Ca(2+) affect muscle tone. When precontracted with 5 micromol/l serotonin, the arteries relaxed in response to cumulative addition of Ca(2+) (1-5 mmol/l) with an ED(50) value for Ca(2+) of 3.30 +/- 0.08 mmol/l, n = 3. These data demonstrate that [Ca(2+)](isf) changes dynamically during manipulation of whole-animal Ca(2+) homeostasis and that intrarenal arteries relax in response to extracellular Ca(2+) varied over the range measured in vivo.

A positron emission tomographic study of auditory localization in the congenitally blind

We have used positron emission tomography (PET) to measure regional cerebral blood flow (rCBF) in sighted and congenitally blind subjects performing auditory localization tasks. During scanning, the spectral and binaural cues of localized sound were reproduced by a sound system and delivered via headphones. During tasks that required auditory localization both the sighted and blind subjects strongly activated posterior parietal areas. In addition, the blind subjects activated association areas in the right occipital cortex, the foci of which were similar to areas previously identified in visual location and motion detection experiments in sighted subjects. The blind subjects, therefore, demonstrated visual to auditory cross-modal plasticity with auditory localization activating occipital association areas originally intended for dorsal-stream visual processing. To determine the functional connectivity of pre-selected brain regions in primary and non-primary auditory and posterior parietal cortex in the two cohorts, we performed an inter-regional correlation analysis on the rCBF data set. During auditory localization in the blind subjects, rCBF activity in the right posterior parietal cortex was positively correlated with that in the right occipital region, whereas in sighted subjects correlations were generally negative. There were no significant positive occipital correlations in either cohort when reference regions in temporal or left parietal cortex were chosen. This indicates that in congenitally blind subjects the right occipital cortex participates in a functional network for auditory localization and that occipital activity is more likely to arise from connections with posterior parietal cortex.

Effect of latrunculin-B on outflow facility in monkeys

Latrunculin-B (LAT-B), a macrolide derived from the marine sponge Latrunculia magnifica, sequesters monomeric G-actin, leading to the disassembly of actin filaments in cultured cells. In this study, we determined the effect of LAT-B on outflow facility in living monkeys. Total outflow facility was measured by 2-level constant pressure perfusion of the anterior chamber (AC) before and immediately after AC exchange infusion or 2 hr after topical application of LAT-B or vehicle. Both AC exchange infusion and topical application of LAT-B dose- and time-dependently increased outflow facility by two- to four-fold. Those findings suggest that pharmacological disorganization of the actin cytoskeleton in the trabecular meshwork by specific actin inhibitors such as LAT-B may be a useful anti-glaucoma strategy.

Expanded CUG repeat RNAs form hairpins that activate the double-stranded RNA-dependent protein kinase PKR

Myotonic dystrophy is caused by an expanded CTG repeat in the 3' untranslated region of the DM protein kinase (DMPK) gene. The expanded repeat triggers the nuclear retention of mutant DMPK transcripts, but the resulting underexpression of DMPK probably does not fully account for the severe phenotype. One proposed disease mechanism is that nuclear accumulation of expanded CUG repeats may interfere with nuclear function. Here we show by thermal melting and nuclease digestion studies that CUG repeats form highly stable hairpins. Furthermore, CUG repeats bind to the dsRNA-binding domain of PKR, the dsRNA-activated protein kinase. The threshold for binding to PKR is approximately 15 CUG repeats, and the affinity increases with longer repeat lengths. Finally, CUG repeats that are pathologically expanded can activate PKR in vitro. These results raise the possibility that the disease mechanism could be, in part, a gain of function by mutant DMPK transcripts that involves sequestration or activation of dsRNA binding proteins.

A least-squares-based 2-D filtering scheme for stereo image compression

A two-dimensional (2-D) least squares (LS)-based filtering scheme for high fidelity stereo image compression applications is introduced in this correspondence. This method removes the effects of mismatching in a stereo image pair by applying the left image as the reference input to a 2-D transversal filter while the right image is used as the desired output. The weights of the filter are computed using a block-based LS method. A reduced order filtering scheme is also introduced to find the optimum number of filter coefficients. The principal coefficients and the disparity vectors are used together with left image to reconstruct the right image at the receiver, The proposed schemes are examined on a real stereo image pair for 3D-TV applications and the results were benchmarked against those of the block-matching method.

Dual streams of auditory afferents target multiple domains in the primate prefrontal cortex

'What' and 'where' visual streams define ventrolateral object and dorsolateral spatial processing domains in the prefrontal cortex of nonhuman primates. We looked for similar streams for auditory-prefrontal connections in rhesus macaques by combining microelectrode recording with anatomical tract-tracing. Injection of multiple tracers into physiologically mapped regions AL, ML and CL of the auditory belt cortex revealed that anterior belt cortex was reciprocally connected with the frontal pole (area 10), rostral principal sulcus (area 46) and ventral prefrontal regions (areas 12 and 45), whereas the caudal belt was mainly connected with the caudal principal sulcus (area 46) and frontal eye fields (area 8a). Thus separate auditory streams originate in caudal and rostral auditory cortex and target spatial and non-spatial domains of the frontal lobe, respectively.

[Intrapulmonary expression of tumor necrosis factor alpha mRNA and its significance in rats with acute pancreatitis]

It is thought that tumor necrosis factor (TNF) plays an important role in pathogenesis of acute lung injury or ARDS. So we want to get insight into the relationship between intrapulmonary expression of TNF-alpha gene and lung injury during acute necrotizing pancreatitis (ANP). In our study, acute edematous pancreatitis (AEP) and ANP were induced in rats by caerulein and sodium taurocholate respectively. After acute pancreatitis was induced, serum TNF-alpha was assessed by ELISA assay while endotoxin was assessed by limulus lysate test. Intrapulmonary expression of TNF-alpha mRNA was detected by semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) technique. Moreover, content of pulmonary lesion was investigated and graded with microscope. It was found that TNF-alpha concentration in blood elevated markedly after acute pancreatitis was induced, especially in ANP group. Results of RT-PCR revealed that no TNF-alpha mRNA could be detected in lung tissue from those rats undergoing sham-operation, but marked expression appeared 1 hour after AEP or ANP was induced. Upregulation of expression of TNF-alpha gene in the early 3 hours was similar in the two groups with pancreatitis, and since then expression of TNF-alpha mRNA in ANP group was stronger than that in AEP group. Serum endotoxin increased significantly 6 hours after ANP was induced, with a higher level at 12 hour. However, there was no marked change of endotoxin level in AEP group and control group. It is noted that intrapulmonary expression of TNF-alpha gene in ANP group reached its peak as soon as serum endotoxin increased markedly. Lung damage in ANP group was more serious than that in AEP group significantly. Score of lung injury correlated well with TNF-alpha concentration in blood and expression of its gene in lung tissue in either AEP group or ANP group, as well as with serum endotoxin in ANP group. So overwhelm expression of some harmful cytokines like TNF-alpha in lung tissue may be the main cause of lung injury during acute necrotizing pancreatitis, and stimulation of endotoxiemia can at least partly explain the upregulation of expression of TNF-alpha gene.

[Clinical protocols for the treatment of severe acute pancreatitis]

OBJECTIVE

To set up principles for the treatment of severe acute pancreatitis (SAP).

METHODS

The therapeutic principles and results of SAP in three periods were analyzed. Period I (1980 - 1990) was characterized by early surgical intervention supplemented with integrated traditional and western medical therapy, period II (1991 - 1993) by integrated traditional and western medical therapy supplemented with surgery for early complications, and period III (1994 - 1997) by integrated traditional and western medical therapy supplemented with surgery for local infectious complications only.

RESULTS

Because of the improvement of intensive care, the operation rates kept declining in the three periods. They were 77.59%, 54.55% and 29.55% with a mortality rate of 40.52%, 17.17% and 11.36%, respectively.

CONCLUSIONS

Integrated traditional and western medicine has been effective in most SAP patients, and surgery is indicated only for late complications such as necrotizing infection. Early surgery should be restricted.

Advances in glaucoma diagnosis and therapy for the next millennium: new drugs for trabecular and uveoscleral outflow

Advances in our understanding of the physiology and molecular biology of the trabecular and uveoscleral outflow pathways of the eye will lead to the development of new approaches for glaucoma therapy. Therapies of the future will target the structures and enzymes involved in maintaining cell shape and cell-cell and cell-extracellular matrix interactions. Altering the extracellular matrix in the ciliary muscle has been important in the intraocular pressure lowering effects of prostaglandins and will be developed further as an approach to enhancing outflow through the trabecular meshwork. Gene therapy may be used to enhance or suppress the endogenous targets that are ultimately responsible for the outflow enhancement triggered by these agents.