Protein phosphatase inhibitor cantharidin inhibits steroidogenesis and steroidogenic acute regulatory protein expression in cultured rat preovulatory follicles

The effect of cantharidin, a natural toxicant of blister beetles and a strong inhibitor of protein phosphatases types 1 and 2A, on luteinizing hormone (LH)-induced synthesis of steroidogenic acute regulatory (StAR) protein was studied in a serum-free culture of preovulatory follicles. StAR protein is a steroidogenic tissue-specific, hormone-induced, rapidly synthesized protein previously shown to be involved in the acute regulation of steroidogenesis, probably by promoting the transfer of cholesterol to the inner mitochondrial membrane and the cytochrome P450 side-chain cleavage (P450scc) enzyme. Treatment of preovulatory follicles dissected from ovaries of immature rats primed with pregnant mares' serum gonadotropin (10 IU) with LH for 24 h resulted in a dose-dependent increase in the level of StAR protein that reached a maximum at 100 ng LH/ml. This increase was associated with an increase in progesterone production. Treatment of follicles with increasing concentrations (10 - 1000 ng/ml) of cantharidin suppresssed LH (100 ng/ml)-induced StAR protein levels and progesterone production in a dose-dependent manner. The amount of P450scc protein and the conversion of 22R-hydroxycholesterol to progesterone were not affected by cantharidin. This indicates that cantharidin did not interfere with the activity of P450scc. Cantharidin also decreased StAR protein levels and progesterone production induced by the adenylate cyclase activator forskolin (10(-5) M) or a cAMP analog 8-Br-cAMP (0.5 mM). These results demonstrate that cantharidin inhibits the LH-induced StAR protein levels, and, thus, suggest that phosphoprotein phosphatase activity is required for the cAMP-protein kinase A-stimulated steroidogenic activity of the preovulatory follicle.

Comparison of speech results after Furlow palatoplasty and von Langenbeck palatoplasty in incomplete cleft of the secondary palate

BACKGROUND

Due to many confounding factors, it is not easy to answer which method of cleft repair is superior to others. The purpose of this study is to try to compare the treatment result of different types of palatoplasty in patients who had the same cleft type and same treatment protocol besides the method of cleft repair. We selected nonsyndromic patients with incomplete cleft of the secondary palate. The speech results after the two palatoplasties were compared.

METHODS

Ninety-six children with nonsyndromic incomplete clefts of the secondary palate who received palatoplasty at the Craniofacial Center of Chang Gung Memorial Hospital from 1989 to 1997 were studied. Forty-six patients received Furlow palatoplasty and 50 patients received von Langenbeck palatoplasty. Velopharyngeal function was evaluated by speech pathologists periodically after the patient was two and half years old. Adequacy of velopharyngeal function was used as a measurement of speech outcome.

RESULTS

The Furlow palatoplasty group showed excellent results with 98% (45/46) adequacy in velopharyngeal function. In the von Langenbeck palatoplasty group, only 70% (35/50) of the patients had adequate velopharyngeal function. Statistical analysis with Fisher's exact test showed a significant difference (p < 0.0001, p < 0.05). Only one patient had an oronasal fistula after Furlow palatoplasty. After von Langenbeck palatoplasty, one patient had an oronasal fistula and one had wound dehiscence.

CONCLUSION

In this study, there was a better speech outcome after Furlow palatoplasty than von Langenbeck palatoplasty for repair of incomplete cleft of the secondary palate. Also, the number of complications after a Furlow palatoplasty was low. It should be a recommended treatment.

Dexamethasone enhances follicle stimulating hormone-induced P450scc mRNA expression and progesterone production in pig granulosa cells

The effect of dexamethasone on follicle-stimulating hormone (FSH)-stimulated expression of cholesterol side-chain cleavage (P450scc) enzyme and production of progesterone by ovarian granulosa cells was studied in vitro. Granulosa cells from 3- to 5-mm pig antral follicles were cultured for 48 h in the presence or absence of FSH and/or dexamethasone. Treatment with FSH resulted in a dose-dependent increase in the level of P450scc mRNA that reached a submaximum at 100 ng FSH/ml. This increase was associated with an increase in progesterone production. Treatment of the cells with increasing concentrations (10(-9)-10(-6) M) of dexamethasone for 48 h increased constitutive and potentiated FSH-stimulated P450scc mRNA levels and progesterone production in a dose-dependent manner. Increasing duration (12-48 h) of treatment with dexamethasone (100 nM) led to a time-dependent increase in basal and FSH-stimulated progesteorne production, achieving statistical significance by 48 and 24 h, respectively. Dexamethasone also increased P450scc mRNA level and progesterone production induced by the adenylate cyclase activator forskolin (10 microM) or a cAMP analog 8-Br-cAMP (1 mM). The effects of dexamethasone on FSH-induced progesterone production were blocked by cotreatment of the cells with glucocorticoid receptor antagonist RU-486. These results demonstrate that dexamethasone potentiates FSH actions on steroidoogenesis in the pig ovary. Possible mechanisms for this potentiation include the ability of dexamethasone to stimulate P450scc gene expression.

Comparison of protein loaded poly(epsilon-caprolactone) microparticles prepared by the hot-melt technique

This study was systematically designed to compare bovine serum albumin (BSA) loaded poly(epsilon-caprolactone) (PCL) microparticles based on a 2(3) factorial experiment. The microparticles were prepared by the holt-melt technique without using an organic solvent for polymer solubilization. The influence of the particle size of protein, protein/polymer ratio, and hydrophilic PEG on the surface morphology, particle size as well as the yield of PCL microparticles, encapsulation efficiency of BSA, and in vitro release properties were investigated. The structure of BSA remained its integrity using this technique. The mean particle size of BSA-loaded microparticles were in the range of 12.7 +/- 0.1-16.9 +/- 0.8 microm, and all of the particles were smooth on the surface. The production yield of microparticles and the encapsulation efficiencies were high, and the values were in the range of 94.8 +/- 1.6%-98.1 +/- 1.0% and 94.9 +/- 9.6%-98.6 + 0.3%, respectively. The burst release of BSA was in the range of 8.2 +/- 0.4%-61.0 +/- 0.8%, which strongly depended on the formulation. None of three variables affected the yield of microparticles prepared from eight formulations (p > 0.05). However, the particle size of BSA significantly affected the size and the burst release as well as the cumulative release of protein in these microparticles (p < 0.05). The initial loading of BSA in terms of BSA/PCL ratio and the amount of PEG blended with PCL significantly affected all of the properties, except the yield (p < 0.05). The smaller the particle size of the BSA, the smaller the size of the resulting microparticles. Since the total surface area of the small particles was larger than that of the large particles, this accounted for the high burst release of protein from the microparticles encapsulating triturated-BSA.

Dual effect of the antianginal drug fendiline on bladder female transitional carcinoma cells: mobilization of intracellular CA2+ and induction of cell death

The effect of fendiline, an antianginal drug, on cytosolic free Ca2+ levels ([Ca2+]i) in populations of bladder female transitional carcinoma (BFTC) cells was explored using fura-2 as a Ca2+ indicator. Fendiline at concentrations between 3 and 200 micromol/l increased [Ca2+]i in a concentration-dependent manner and the signal saturated at 100 micromol/l. The [Ca2+]i signal was biphasic, with an initial rise and a slow decay. Ca2+ removal inhibited the Ca2+ signal by about half in peak amplitude. Adding 3 mmol/l Ca2+ increased [Ca2+]i in cells pretreated with 100 micromol/l fendiline in Ca2+ -free medium, suggesting that fendiline induced Ca2+ influx via capacitative Ca2+ entry. In Ca2+ -free medium, pretreatment with 1 micromol/l thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) to deplete the endoplasmic reticulum Ca2+ store inhibited most of the 100 micromol/l fendiline-induced internal Ca2+ release; and conversely, pretreatment with 100 micromol/l fendiline partly inhibited 1 micromol/l thapsigargin-induced Ca2+ release. This indicates that the major internal Ca2+ store of fendiline-induced [Ca2+]i increases is located in the endoplasmic reticulum. The Ca2+ release induced by 100 micromol/l fendiline may be partly mediated by inositol 1,4,5-trisphosphate, because the [Ca2+]i increase was inhibited by 50% by inhibiting phospholipase C with 2 micromol/l U73122. Fendiline (100 micromol/l) decreased cell viability by 12-44% after being added to cells for 2- 30 min. Together, the findings indicate that in BFTC cells, fendiline exerts a dual effect: mobilization of intracellular Ca2+ and induction of cell death.

Fendiline, an anti-anginal drug, increases intracellular Ca2+ in PC3 human prostate cancer cells

BACKGROUND

The effects of the anti-anginal drug fendiline on intracellular Ca2+ concentrations ([Ca2+]i) in human PC3 prostate cancer cells were examined.

METHODS

[Ca2+]i was measured using the fluorescent dye fura-2.

RESULTS

Fendiline (0.5-100 microM) increased [Ca2+]i in a concentration-dependent manner. Ca2+ removal partly inhibited the Ca2+ signals. In Ca2+-free medium, pretreatment with 100 microM fendiline inhibited most of the [Ca2+]i increase induced by 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), and pretreatment with thapsigargin abolished the fendiline-induced [Ca2+]i increases. Adding 3 mM Ca2+ increased [Ca2+]i in cells pretreated with 0.5-200 microM fendiline in Ca2+-free medium. Pretreatment with 1 microM U73122 to block the formation of inositol-1.4.5-trisphosphate (IP3) did not alter fendiline-induced internal Ca2+ release.

CONCLUSIONS

The anti-anginal drug fendiline induced internal Ca2+ release and external Ca2+ entry. Because prolonged increases in [Ca2+]i may lead to cell injury and death, the long-term effect of fendiline on the function of prostate cancer cells should be investigated.

Lead chelation therapy and urate excretion in patients with chronic renal diseases and gout

BACKGROUND

It is known that chronic renal insufficiency (CRI) patients with gout may have subtle lead poisoning. In addition, gout episodes frequently aggravate progressive renal insufficiency because of the use of nephrotoxic drugs and urate deposition. Our study was arranged to evaluate the causal effect of environmental lead exposure on urate excretion in CRI patients.

METHODS

A cross-section study and a randomized, controlled trial were performed. Initially, 101 patients with CRI and without a history of previous lead exposure received ethylenediaminetetraacetic acid mobilization tests to assess body lead stores (BLS). Then, a clinical trial was performed; 30 CRI patients with gout and high-normal BLS and the changes of urate excretion in these patients were compared before and after lead chelating therapy. The treated group received four-week chelating therapy, and the control group received a placebo therapy.

RESULTS

The BLS of patients with CRI and gout was higher than that of patients with CRI only, and none had subtle lead poisoning. The BLS, not the blood lead level (BLL), significantly correlated to indices of urate excretion in all CRI patients after related factors were adjusted. In addition, after lead chelating therapy, urate clearance markedly improved after a reduction of the BLS of patients with CRI and gout (study group 67.9 +/- 80.0% vs. control group 1.2 +/- 34.0%, P = 0.0056).

CONCLUSION

Our findings suggest that the chronic low-level environmental lead exposure may interfere with urate excretion of CRI patients. Importantly, the inhibition of urate excretion can be markedly improved by lead chelating therapies. These data shed light on additional treatment of CRI patients with gout; however, more studies are needed to confirm our findings.

Mycophenolate mofetil reduces renal cortical inducible nitric oxide synthase mRNA expression and diminishes glomerulosclerosis in MRL/lpr mice

Overexpression of inducible nitric oxide synthase (iNOS) has been implicated in the pathogenesis of lupus glomerulonephritis. Mycophenolate mofetil (MMF), a novel immunosuppressive agent, is currently used in organ transplantation and under evaluation for treatment of autoimmune disorders. Mycophenolic acid, the active metabolite of MMF, has been shown to suppress cytokine-induced nitric oxide production in vitro. The aim of this study was to evaluate the effect of MMF on the expression of renal cortical iNOS mRNA and protection against glomerulonephritis in MRL/lpr mice. Three-month-old MRL/lpr mice (n = 6) displaying clinical symptoms of glomerulonephritis were treated for 3 months with MMF (90 mg/kg/day) dissolved in a vehicle. Controls were age- and sex-matched mice (n = 6) that received the vehicle alone. By reverse-transcription competitive polymerase chain reaction, we found that the renal cortical iNOS/beta-actin mRNA ratio was reduced by 30.8% (P <.05) in MMF-treated mice. Furthermore, MMF significantly reduced urinary nitrite production and degree of glomerulosclerosis. The glomerular volume was reduced by 17.5% (P <.001). Proteinuria was also significantly reduced in the MMF-treated group. However, by electrophoretic mobility shift assay, the nuclear binding of nuclear factor-kappaB (NF-kappaB) was not affected by MMF treatment. We conclude that in addition to its immunosuppressive action, MMF may reduce renal cortical iNOS mRNA expression and diminish glomerulosclerosis in MRL/lpr mice independent of modulation of the NF-kappaB pathway.

In vivo pressure-flow curve in unilateral rat lung ischemia-reperfusion injury

The pressure-flow (P-Q) curve has been widely used in many studies to describe the effects of various factors on vascular hemodynamics. It is not clear, however, whether unilateral ischemia-reperfusion (IR) alters the P-Q curve of the rat lung. In this study, we developed an in vivo P-Q curve using the unilateral (left) rat lung before and after IR. Animals were divided into two groups: sham and IR. The protocol of the IR group consisted of three periods: baseline, ischemia, and reperfusion. P-Q curves were obtained by altering blood flow of the left lung during the baseline and the reperfusion periods. The sham group received the same operation without IR procedure. An additional group was used to compare pulmonary blood flow measured by the microsphere and the ultrasonic methods. IR treatment rotated the P-Q curve toward the left, indicating an increase in resistance in the left lung. However, this rotation was not found in the sham group. A significant correlation (r = 0.87, P < 0.01) between percentages of blood flow obtained by the microsphere and ultrasonic methods in both right and left lungs was demonstrated. Therefore, we demonstrated a simple and useful technique to evaluate changes in the P-Q curves caused by IR in the unilateral rat lung model.

Clomiphene, an Ovulation-Inducing Agent, Mobilizes Intracellular Ca2+ and Causes Extracellular Ca2+ Influx in Bladder Female Transitional Carcinoma Cells

BACKGROUND/METHODS

The effect of clomiphene, an ovulation-inducing agent, on cytosolic free Ca2+ levels ([Ca2+]i) in populations of BFTC human bladder cancer cells was explored by using fura-2 as a Ca2+ indicator.

RESULTS

Clomiphene at concentrations between 10 and 75 microM increased [Ca2+]i in a concentration-dependent manner and the signal saturated at 50 microM. The [Ca2+]i signal was biphasic with an initial rise and a slow decay. Ca2+ removal inhibited the Ca2+ signal by about 40-50% in maximum [Ca2+]i. Adding 3 mM Ca2+ increased [Ca2+]i in cells pretreated with 50 microM clomiphene in Ca2+-free medium, suggesting that clomiphene induced capacitative Ca2+ entry. In Ca2+-free medium, pretreatment with 50 microM brefeldin A (to disrupt the Golgi complex Ca2+ store), 1 microM thapsigargin (to inhibit the endoplasmic reticulum Ca2+ pump), and CCCP (to uncouple mitochondria) inhibited 85% of clomiphene-induced intracellular Ca2+ release. Conversely, pretreatment with 50 microM clomiphene in Ca2+-free medium abolished the [Ca2+]i increase induced by brefeldin, thapsigargin or CCCP. The intracellular Ca2+ release was unaltered by inhibiting formation of inositol-1,4,5-trisphosphate (IP3) with 2 mM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122; a phospholipase C inhibitor).

CONCLUSION

The [Ca2+]i increase induced by 50 microM clomiphene was not affected by 10 microM of nifedipine, verapamil or diltiazem. Collectively, the results suggest that clomiphene releases intracellular Ca2+ in an IP3-independent manner and also activates extracellular Ca2+ influx.

Telomerase is regulated by protein kinase C-zeta in human nasopharyngeal cancer cells

Telomerase, a specialized ribonucleoprotein reverse transcriptase that directs the synthesis of telomeric DNA, is repressed in normal human somatic cells, but is activated in most cancers. Little is known concerning how telomerase activity is activated and maintained in cancer cells. We have shown previously that inhibition of protein kinase C (PKC) decreases the telomerase activity of human nasopharyngeal carcinoma (NPC) cells. Here, we provide evidence that the decrease of telomerase activity by PKC inhibition is not mediated by transcriptional down-regulation of hTERT, the catalytic protein of human telomerase. In vitro phosphorylation studies revealed that exogenous addition of PKC-alpha, -betaI, -delta or -zeta led to restoration of telomerase activity in the crude extracts of PKC-inhibited NPC cells. However, depletion of PKC-alpha and -betaI in vivo had no detectable effect on the telomerase activity of NPC cells. Using antisense oligonucleotides against individual PKC isotypes, we observed that telomerase activity was inhibited only by the antisense oligonucleotide against PKC-zeta but not by those against PKC-alpha, -betaI or -delta. Taken together, these data demonstrate that PKC participates in the regulation of telomerase activity by direct or indirect phosphorylation of telomerase proteins, and that PKC-zeta is the PKC isotype that functions in vivo in the NPC cells.

Environmental lead exposure and progressive renal insufficiency

BACKGROUND

Several recent studies show that serum creatinine level or creatinine clearance is inversely associated with blood lead levels. However, the studies did not allow direct inferences about causality.

OBJECTIVE

To evaluate the relation between body lead burden (BLB) and progressive renal insufficiency in patients without previous heavy lead exposure.

DESIGN

A prospective, longitudinal study with a controlled clinical trial.

PATIENTS

One hundred ten patients with chronic renal insufficiency (serum creatinine level, 133-354 micromol/L [1.5-4.0 mg/dL]) and normal BLB (EDTA mobilization tests, <600 microg per 72-hour urine collection) and without a history of previous heavy lead exposure were divided into 2 groups according to BLB: the high-normal BLB group (BLB > or =80 microg and <600 microg) and the low BLB group (BLB <80 microg). Patients were prospectively followed up for 2 years.

MAIN OUTCOME MEASURES

The primary outcome was a 1.5 times increase in the initial creatinine level. The secondary outcome was a change over time in the value of creatinine clearance. At the end of follow-up, a 3-month clinical trial with chelation therapy for patients with high-normal BLB was performed to clarify the role of environmental lead exposure in progressive renal insufficiency.

RESULTS

Fifteen patients (14 in the high-normal BLB group and 1 in the low BLB group) reached the primary outcome within 24 months. Renal outcome was significantly better in the low BLB group (P<.001). From month 12 to month 24, renal function of high-normal BLB patients had a greater rate of progressive renal insufficiency than that of low BLB patients. In the Cox multivariate regression analysis, BLB was the most important risk factor for determining the progression of renal insufficiency. After chelation therapy, significant improvement in renal function was noted. In addition, the effect of improving renal function lasted for more than 12 months in these patients.

CONCLUSIONS

Long-term low-level environmental lead exposure may subtly affect progressive renal insufficiency in the general population. Progressive renal insufficiency may be improved for at least 1 year after lead chelating therapy. Further investigations are needed to clarify this observation.

Lupus-like kidney disease in mice deficient in the Src family tyrosine kinases Lyn and Fyn

Systemic lupus erythematosus (SLE) is an autoimmune disease whose cause is poorly understood. Mice rendered deficient in specific genes have served as useful animal models in deciphering the genetic control of the disease [1]. We [2] and others [3, 4] previously demonstrated that mice deficient in the Src family tyrosine kinase Lyn developed a mild lupus-like disease with high survival rates. During the course of investigating the functional interaction of Src family kinases, we generated a mouse strain deficient in both Lyn and Fyn. The double-mutant mice died at relatively young ages and developed a severe lupus-like kidney disease. Unlike the double-mutant mice, single mutants deficient in either Lyn or Fyn lived longer and had distinct subsets of the symptoms found in the former. Lyn deficiency led to high levels of autoantibody production and glomerulonephritis, as previously reported [2--4], whereas loss of Fyn contributed to proteinuria by a B and T lymphocyte-independent mechanism. Our data suggest that the severe kidney disease in the double-mutant mice results from a combination of immunological and kidney-intrinsic defects. This new animal model may be informative about the causes of human SLE.

Oxygen- and growth rate-dependent regulation of Escherichia coli fumarase (FumA, FumB, and FumC) activity

Escherichia coli contains three biochemically distinct fumarases which catalyze the interconversion of fumarate to L-malate in the tricarboxylic acid cycle. Batch culture studies indicated that fumarase activities varied according to carbon substrate and cell doubling time. Growth rate control of fumarase activities in the wild type and mutants was demonstrated in continuous culture; FumA and FumC activities were induced four- to fivefold when the cell growth rate (k) was lowered from 1.2/h to 0.24/h at 1 and 21% O(2), respectively. There was a twofold induction of FumA and FumC activities when acetate was utilized instead of glucose as the sole carbon source. However, these fumarase activities were still shown to be under growth rate control. Thus, the activity of the fumarases is regulated by the cell growth rate and carbon source utilization independently. Further examination of FumA and FumC activities in a cya mutant suggested that growth rate control of FumA and FumC activities is cyclic AMP dependent. Although the total fumarase activity increased under aerobic conditions, the individual fumarase activities varied under different oxygen levels. While FumB activity was maximal during anaerobic growth (k = 0.6/h), FumA was the major enzyme under anaerobic cell growth, and the maximum activity was achieved when oxygen was elevated to 1 to 2%. Further increase in the oxygen level caused inactivation of FumA and FumB activities by the high oxidized state, but FumC activity increased simultaneously when the oxygen level was higher than 4%. The same regulation of the activities of fumarases in response to different oxygen levels was also found in mutants. Therefore, synthesis of the three fumarase enzymes is controlled in a hierarchical fashion depending on the environmental oxygen that the cell encounters.

N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride) (W-7) causes increases in intracellular free Ca2+ levels in bladder female transitional carcinoma (BFTC) cells

The effect of N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride) (W-7), a widely used calmodulin inhibitor, on intracellular free Ca2+ levels ([Ca2+]i) in bladder female transitional cancer (BFTC) cells was examined using fura-2 as a Ca2+ dye. W-7 (10-1000 microM) caused an increase in [Ca2+]i in a concentration-dependent manner with an EC50 of 75 microM. The [Ca2+]i response was composed of an initial rise and a sustained plateau without significant decaying during the measurement of 250 seconds. Extracellular Ca2+ removal dramatically decreased the Ca2+ signals by 50-90%. W-7 (100 microM) failed to induce a [Ca2+]i increase in Ca(2+)-free medium after pretreatment with thapsigargin (1 microM), an endoplasmic reticulum Ca2+ pump inhibitor; conversely, W-7 pretreatment abolished the Ca2+ release induced by thapsigargin. Addition of 3 mM Ca2+ increased [Ca2+]i after preincubation with 100 microM W-7 in Ca(2+)-free medium. W-7-induced Ca2+ release was not altered by inhibiting phospholipase C with 2 microM 1-(6-((17b-3-methoxyestra-1,3,5 (10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione) (U73122). Together, this study shows that W-7 caused [Ca2+]i increases in human bladder cancer cells by releasing intracellular Ca2+ from the endoplasmic reticulum and also by causing extracellular Ca2+ influx with the later playing a dominant role. The W-7-induced intracellular Ca2+ release was uncoupled to a prior elevation in intracellular levels of inositol 1,4,5-trisphosphate (IP3).

NPC-15199, a novel anti-inflammatory agent, mobilizes intracellular Ca2+ in bladder female transitional carcinoma (BFTC) cells

This report demonstrates that NPC-15199 [(N-(9-fluorenylmethoxycarbonyl)L-leucine)], a novel anti-inflammatory agent, increases intracellular Ca2+ concentration ([Ca2+]i) in human bladder female transitional cancer (BFTC) cells. Using fura-2 as a Ca2+ probe, NPC-15199 (0.1-2 mM) was found to increase [Ca2+]i concentration-dependently. The response saturated at 2-5 mM NPC-15199. The [Ca2+]i increase comprised an initial rise, a slow decay, and a plateau. Ca2+ removal partly inhibited the Ca2+ signals. In Ca2+-free medium, pretreatment with 1 mM NPC-15199 abolished the [Ca2+]i increase induced by 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor); and after pretreatment with thapsigargin, NPC-15199-induced Ca2+ release was dramatically inhibited. This indicates that NPC-15199 released internal Ca2+ mostly from the endoplasmic reticulum. Adding 3 mM Ca2+ increased [Ca2+]i in cells pretreated with 1 mM NPC-15199 in Ca2+-free medium. Together, the findings suggest that in BFTC bladder cancer cells, NPC-15199 induced Ca2+ release from the endoplasmic reticulum and activating Ca2+ entry.

Ectopic pancreatic rests: a rare cause of persistent umbilical discharge

Ectopic pancreatic rests are rare. We report two cases discovered in infants who underwent surgical exploration of the umbilicus for persistent umbilical discharge with peri-umbilical excoriation. A shallow sinus leading to a firm cyst was excised in both infants, and histopathological study confirmed the presence of exocrine and endocrine pancreatic tissue. There is only one other case of ectopic umbilical pancreatic tissue reported, and this was in a patient presenting with an umbilical mass.

Novel strategy for efficient screening and construction of host/vector systems to overproduce penicillin acylase in Escherichia coli

A novel and simple method of using penicillin for screening of mutant strains with a high penicillin acylase (PAC) activity was developed. Random mutagenesis was conducted using a PAC-producing strain resistant to 6-aminopenicillanic acid (6-APA) as the parent strain and mutants were screened with penicillin at a high concentration. Results suggest that mutants with a high minimum inhibitory concentration for penicillin (MIC(penG)) usually overproduce PAC. Both volumetric and specific PAC activities of a mutant, MD7, were significantly higher than those of the parent strain, HBPAC101 harboring pCLL2902. The mutation(s) resulting in the enhanced expression was mapped on the host chromosome rather than the plasmid. In addition, the mutant strain of MDDeltaP7, derived by elimination of the harbored plasmid in MD7, was demonstrated to be efficient in production of PAC by using the expression plasmids for which expression of the pac gene is limited by translation. An extremely high specific PAC activity of more than 350 U/L/OD(600) was reached upon cultivation of MDDeltaP7 harboring pTrcKnPAC2902 in a bioreactor. As such, the strategy is effective in terms of constructing PAC overproducers and improving the process yield for production of PAC.

Local supplementation of ketoprofen reduces the incidence of low back pain after lumbar epidural anesthesia

BACKGROUND

Backache is a common postoperative complaint after lumbar epidural anesthesia. Our study was aimed to compare the effect of the local addition of ketoprofen on the incidence of postepidural backache after nonobstetric surgery.

METHODS

One thousand patients scheduled for hemorrhoidectomy were randomly given 4 ml of 1% lidocaine with ketoprofen 1:400 (ketoprofen group) or without ketoprofen (control group) for local skin infiltration prior to epidural needle placement. Each of them received a single epidural injection of 25 ml 2% lidocaine with epinephrine 1:200000, and was interviewed 24, 48, and 72 hours postoperatively using a standard visual analog scale (VAS) for evaluation of postepidural backache.

RESULTS

The incidence of postepidural backache in the ketoprofen-group patients for the 3 days was 9.8%, 4.6%, and 1.8%, all rates which were significantly less than those observed in the control-group patients (22.8%, 17.4%, and 9.2%, p < 0.001). There was also a significant association between postepidural backache and multiple attempts at epidural needle insertion.

CONCLUSION

In summary, the local addition of ketoprofen reduced the incidence and severity of postepidural backache.

Pre-dialysis glycemic control is an independent predictor of mortality in type II diabetic patients on continuous ambulatory peritoneal dialysis

OBJECTIVE

To evaluate the impact of pre-dialysis glycemic control on clinical outcomes for type II diabetic patients on continuous ambulatory peritoneal dialysis (CAPD).

MATERIALS AND METHODS

One hundred and one type II diabetic patients receiving CAPD for at least 3 months were enrolled in a single institute. The patients were classified into two groups according to status of glycemic control. In the good glycemic control group, more than 50% of blood glucose determinations were within 3.3-11.0 mmol/L and glycosylated hemoglobin (HbA1C) levels were within 5%-10% at all times. In the poor glycemic control group, less than 50% of blood glucose determinations were within 3.3-11.0 mmol/L, or HbA1C levels were above 10% at least 6 months before peritoneal dialysis was started. In addition to glycemic control status, pre-dialysis serum albumin, cholesterol levels, residual renal function, peritoneal membrane function, and modes of glycemic control were also recorded.

RESULTS

The patients with good glycemic control had significantly better survival than those with poor glycemic control (p < 0.01). There was no significant difference in pre-dialysis morbidity between two groups. No significant differences were observed in patient survival between patients with serum albumin above 30 g/L and those with serum albumin under 30 g/L; between those with cholesterol levels above or below 5.2 mmol/L; and between those with different peritoneal membrane solute transport characteristics as evaluated by a peritoneal equilibration test (PET). Furthermore, there was no significant difference in survival between patients who controlled blood sugar by diet and those who controlled it by insulin. Cardiovascular disease and infection are the major causes of death in both groups. Although good glycemic control predicts better survival, it does not change the pattern of mortality in diabetic patients maintained on CAPD.

CONCLUSIONS

Glycemic control before starting dialysis is a predictor of survival for type II diabetic patients on CAPD. Patients with poor glycemic control predialysis are associated with increased morbidity and shortened survival.

The role of components of recombination signal sequences in immunoglobulin gene segment usage: a V81x model

It has long been appreciated that some immunoglobulin (and T-cell receptor) gene segments are used much more frequently than others. The VHsegment V81x is a particularly striking case of overusage. Its usage varies with the stage of B-cell development and with the strain of mice, but it is always high in B cell progenitors. We have found that the coding sequence and the recombination signal sequences (RSS) are identical in five mouse strains, including CAST/Ei, a strain derived from the species Mus castaneus. Thus, the strain differences cannot be attributed to sequences within V81x itself. V81x RSS mediated recombination at rates significantly higher than another VHRSS. Although the V81x nonamer differs at one base pair from the consensus sequence, an RSS with this nonamer and a consensus heptamer recombines as well as the consensus RSS. When the V81x spacer is replaced by that of VA1, the frequency of recombination decreases by approximately 5-fold; thus, the contribution of variation in natural spacers to variability in VHusage in vivo is likely to be more than has been previously appreciated. Furthermore, the contribution of the heptamer and nonamer to differential VHusage in our assay is correlated inversely with their conservation throughout the VHlocus.

Genetic manipulation to identify limiting steps and develop strategies for high-level expression of penicillin acylase in Escherichia coli

We have identified the bottleneck steps limiting expression of penicillin acylase (PAC) through comparison of the expression performance for various PAC-expression vectors constructed by genetically modulating the efficiencies of transcription and/or translation of the pac gene. To our knowledge, this is the first report demonstrating that expression of PAC could be limited by various steps, such as transcription, translation, and post-translational steps (i.e. translocation and periplasmic processing), depending on the host/vector systems. Results also indicate that the structure of the wild-type pac gene might not be optimal for direct use in production of PAC using recombinant DNA technology. To improve the gene expression, transcription was enhanced by manipulating certain DNA bases in the pac regulatory region, whereas translation was enhanced by enlarging the spacing between the ribosome binding site and the ATG initiation codon to increase the initiation efficiency. The information is useful in terms of developing genetic strategies for overproduction of recombinant PAC in Escherichia coli.

Risk of gonadoblastoma in female patients with Y chromosome abnormalities and dysgenetic gonads

We report two female patients with gonadal dysgenesis and sex chromosome mosaicism involving the Y chromosome. Conventional karyotyping was supplemented with fluorescent in situ hybridisation techniques in order to confirm the presence of Y chromosomes. One patient is a phenotypic female with karyotype 45,X/46,X,idic(Y)(q11.2). She underwent a laparoscopic gonadectomy at which streak ovaries without evidence of gonadoblastoma were removed. The second patient presented as a virilised female with karyotype 45,X/47,XYY. At laparoscopy, she was found to have mixed gonadal dysgenesis with a gonadoblastoma in situ. We recommend early gonadectomy in female children presenting with gonadal dysgenesis and the presence of a Y chromosome although once the gonadoblastoma locus on Y chromosome gene has been cloned it may be possible to identify those patients who have a low risk of developing gonadoblastoma.

Manipulation of carbon assimilation with respect to expression of the pac gene for improving production of penicillin acylase in Escherichia coli

A strategy of genetically manipulating carbon assimilation with respect to expression of the pac gene was employed for overproduction of recombinant penicillin acylase (PAC). Two expression plasmids of pCLL2902 and pCLL3201, which contain the pac coding region but differ in the pac regulatory region, were constructed for the production experiments. Expression of the pac gene was subjected to phenyl acetic acid (PAA-) induction and glucose catabolite repression for pCLL3201, whereas it was subjected to neither of the two transcriptional regulations for pCLL2902. The specific PAC activity for strains harboring pCLL2902 was significantly higher than that for strains harboring pCLL3201 due to an improved transcription efficiency. In addition, no inclusion bodies were observed upon production of PAC using the current expression systems. The results suggest that using the native pac promoter instead of a strong promoter such as tac for regulation is a feasible approach for production of PAC. The impact of the current expression systems is also significant from a process viewpoint since, using strains harboring pCLL2902, not only could glucose replace PAA as a carbon source of Escherichia coli cultures for production of PAC but also the volumetric PAC activity was highly improved.