Formation and properties of proton-exchanged and annealed LiNbO3 waveguides for surface acoustic wave

The proton-exchanged (PE) and annealed PE (APE) z-cut LiNbO3 waveguides were fabricated using H4P2O7. The positive strain, c-axis lattice constant change (delta C/C), was calculated to be about +0.43%, which was almost independent of the exchanged conditions. The penetration depth of H measured by secondary ion mass spectrometry (SIMS) exhibited a step-like profile, which was assumed to be equal to the waveguide depth (d). The surface acoustic wave (SAW) properties of PE and APE z-cut LiNbO3 samples were investigated. The phase velocity (Vp) and electromechanical coupling coefficient (K2) of PE samples were significantly decreased by the increase of kd, where k was the wavenumber (2 pi/lambda). The insertion loss (IL) of PE samples was increased by the increase of kd and became nearly constant at kd > 0.064. The temperature coefficient of frequency (TCF) of PE samples showed an apparent increase with kd, reaching a maximum at kd = 0.292, then slightly decreased at higher kd. The effects of annealing resulted in a restoration of Vp and an improvement of IL.

Alternative activation of extracellular signal-regulated protein kinases in curcumin and arsenite-induced HSP70 gene expression in human colorectal carcinoma cells

We have investigated the regulation mechanism of chemical stress-induced HSP70 gene expression in human colorectal carcinoma cells (COLO205 and HT29). Our data show that chemical treatments including sodium arsenite and curcumin, induced significant synthesis of HSP70 and its mRNA. The induced HSP70 gene expression appears to be increased at the transcriptional level. The increase in HSP70 gene expression by both chemicals is associated with an increase in HSF binding to HSE and induction of HSF1 di- or trimerization. Phosphorylation and activation of extracellular signal-regulated proteins (ERK1/2) were detected in sodium arsenite-treated COLO205 and HT29 cells, and the free radical scavenger N-acetyl-L-cysteine (NAC) was able to inhibit this ERK1/2 activation and HSP70 gene expression. MAPK blockade by the specific MEK1 inhibitor (PD98059) decreased the ability of sodium arsenite to increase HSP70 gene expression in a dose-dependent manner along with dephosphorylation of ERK1/2 proteins. In contrast to arsenite treatment, activation of ERK1/2 was not detected in curcumin-treated colorectal carcinoma cells, and NAC and PD98059 did not show any inhibitory effect on HSP70 gene expression induced by curcumin. Overexpression of a dominant negative mutant of mitogen-activated protein kinase kinase kinase 1 (MEKK1-DN) prevents arsenite-induced ERK1/2 phosphorylation and HSP70 protein synthesis. These results indicated that the ERK signaling pathway can participate in HSP70 gene expression induced by the prooxidant sodium arsenite, but not by the antioxidant curcumin.

Antibiotic use in public hospitals in Taiwan after the implementation of National Health Insurance

BACKGROUND AND PURPOSE

Only limited data is available on the patterns of antibiotic use in hospitals in Taiwan before and after the implementation of national health insurance. This study aimed to determine the patterns of use of antibiotics in public hospitals in Taiwan after the implementation of the National Health Insurance program and to compare these with patterns prior to the implementation.

METHODS

Data on the annual use of all antibiotics in public hospitals in Taiwan during the period from fiscal year (FY) 1994-1995 to 1997-1998 were collected and analyzed. Hospitals included seven medical centers, 19 regional hospitals, 53 district hospitals, and eight specialty service hospitals.

RESULTS

The annual cost of antibiotics made up 17.4% of the annual cost of all medication used in these hospitals in FY 1994-1995, and decreased year by year to 12.6% in FY 1997-1998. During the study period, 57.4% of the total cost of antibiotics were incurred by medical centers, 24.6% by regional hospitals, 16.2% by district hospitals, and 1.8% by specialty service hospitals. The most commonly used class of antibiotic was cephalosporins, accounting for 48.0% to 54.3% of total antibiotic costs. The second most commonly used class of antibiotic was penicillins, accounting for 15.9% to 17.4% of total antibiotic costs. In FY 1994-1995, the next most commonly used classes of antibiotics were aminoglycosides, fluoroquinolones, and other beta-lactams, respectively, but by FY 1997-1998 these had changed to fluoroquinolones, glycopeptides, and aminoglycosides, respectively. Among the various cephalosporins used, first-generation cephalosporins accounted for 76.1% of all cephalosporins used in FY 1994-1995, which increased year by year to 84.0% in FY 1997-1998. Second-generation cephalosporins accounted for 20.7% of all cephalosporins used in FY 1994-1995, decreasing to 13.2% in FY 1997-1998.

CONCLUSION

The introduction of the National Health Insurance program in Taiwan brought about a major change in antibiotic use patterns in public hospitals.

Hypokalemic muscular paralysis causing acute respiratory failure due to rhabdomyolysis with renal tubular acidosis in a chronic glue sniffer

CASE REPORT

A 34-year-old male was admitted to the emergency department with the development of quadriparesis and respiratory failure due to hypokalemia after prolonged glue sniffing. The patient was subsequently given mechanical ventilatory support for respiratory failure. He was weaned from the ventilator 4 days later after potassium replacement. Toluene is an aromatic hydrocarbon found in glues, cements, and solvents. It is known to be toxic to the nervous system, hematopoietic system, and causes acid-base and electrolyte disorders. Acute respiratory failure with hypokalemia and rhabdomyolysis with acute renal failure should be considered as potential events in a protracted glue sniffing.

Loss of p16 and/or pRb protein expression in NSCLC. An immunohistochemical and prognostic study

The disruption of p16/pRb pathway has been reported in several types of human cancer including lung cancer. However, the etiological and prognostic involvement of this pathway remains poorly defined in lung tumorigenesis in Taiwan. Therefore, we investigated the expressions of p16 and pRb in 107 non-small cell lung cancer (NSCLC) patients by immunohistochemical analysis. The associations of altered p16 and pRb expressions with prognosis were also examined. Sixty-four specimens (59.8%) exhibited alteration of p16 and/or pRb expression, with 49.5 and 22.4% of the tumors failing to express p16 and pRb, respectively. However, there was no reciprocally correlated expression of p16 and pRb. Negative p16 and pRb expression did not correlate well with patients' clinicopathological parameters such as age, sex, smoking habit, tumor type, and tumor stage. In addition, negative p16 and pRb expression was not statistically associated with poor prognosis (P=0.10 and P=0.74, respectively). Our results suggested that the disruption of the p16/pRb pathway plays a significant role in NSCLC tumorigenesis whereas it may not have significant importance in the prognostic evaluation of NSCLC in Taiwan.

Mechanisms involved in the inhibition of neointimal hyperplasia by abciximab in a rat model of balloon angioplasty

Monoclonal antibodies raised against beta(3) integrin are able to inhibit the binding of ligands to certain beta(3) integrins such as alpha(IIb)beta(3) (glycoprotein IIb/IIIa complex) and alpha(v)beta(3) (vitronectin receptor) and as such are inhibitors of platelet aggregation and smooth muscle cell (SMC) migration, both of which are involved in neointimal hyperplasia. The present study was designed to explore the detailed mechanisms of abciximab (Reopro), a monoclonal antibody (mAb) raised against alpha(IIb)beta(3) integrin in neointimal hyperplasia. In this study, carotid arteries of Wistar rats were damaged, and neointimal hyperplasia and lumen occlusion was determined at different time points. Abciximab was administered intravenously by an implanted osmotic pump. Abciximab (0.25 mg/kg/day) time-dependently inhibited both neointimal hyperplasia and lumen occlusion after angioplasty in carotid arteries of rats. Furthermore, the electromicrographs highlighted that SMCs were phenotypically different from the typical contractile, spindle-shaped SMCs normally seen in uninjured vessel walls. Platelet-derived growth factor (PDGF)-BB was strongly produced in thrombus formation and neointimal SMCs after angioplasty, while abciximab significantly reduced PDGF-BB expression in vessel lumens and neointimal SMCs after angioplasty. Balloon angioplasty caused a significant increase of nitrate and cyclic GMP as compared with sham-operated rats. Infusion of abciximab (0.25 mg/kg/day) did not significantly change. Furthermore, the plasma level of thromboxane B(2) (TxB(2)) obviously increased after angioplasty, while abciximab markedly suppressed the elevation of plasma TxB(2) concentration. The results indicate that abciximab effectively prevents neointimal hyperplasia, possibly through the following 2 mechanisms: (1) Abciximab binds to alpha(IIb)beta(3) integrin on platelet membranes resulting in inhibition of platelet adhesion, secretion, and aggregation in injured arteries, followed by inhibition of thromboxane A(2) formation and PDGF-BB release from platelets. (2) Abciximab may also bind to alpha(v)beta(3) integrin on SMCs, thus, subsequently inhibiting cell migration and proliferation.

[Histopathological observation of experimental slight viral myocarditis]

To study the diagnostic method of slight viral myocarditis in the field of forensic pathology, slight viral myocarditis model was induced in Balb/c murine by coxsackie virus B3. Organs of hearts, livers, spleens, lungs and kidneys were examined through routine pathological methods. Pathological changes at different levels of these organs were observed. The results indicated that viral myocarditis was a kind of disease with multiple organ alterations and that the pathological observation and comprehensive analysis of multiple organs was one of the useful methods for diagnosing slight viral myocarditis.

Determination of trace quaternary ammonium surfactants in water by combining solid-phase extraction with surface-assisted laser desorption/ionization mass spectrometry

This study demonstrates the feasibility of combining solid-phase extraction (SPE) with surface-assisted laser desorption/ionization (SALDI) mass spectrometry to determine trace quaternary ammonium surfactants in water. The trace surfactants in water were directly concentrated on the surface of activated carbon sorbent in SPE. The activated carbon sorbent was then mixed with the SALDI liquid for SALDI analysis. No SPE elution procedure was necessary. Experimental results indicate that the surfactants with longer chain alkyl groups exhibit higher sensitivities than those with shorter chain alkyl groups in SPE-SALDI analysis. The detection limit for hexadecyltrimethylammonium bromide is around 10 ppt in SPE-SALDI analysis by sampling 100 mL of aqueous solution, while that of tetradecyltrimethylammonium bromide is about 100 ppt. The detection limit for decyltrimethylammonium bromide and dodecyltrimethylammonium bromide is in the low-ppb range.

Comparison of MALT and non-MALT primary large cell lymphoma of the stomach: does histologic evidence of MALT affect chemotherapy response?

BACKGROUND

Although the clinicopathologic features of low grade gastric MALToma (lymphoma of mucosa-associated lymphoid tissue) recently have been well delineated, the significance of identifying histologic evidence of MALT origin in a primary high grade gastric lymphoma is less clear. The authors sought to address this issue and, in particular, to clarify if MALT and non-MALT primary large cell gastric lymphoma might have a different response to systemic chemotherapy.

METHODS

The authors reviewed the pathologic specimens of all patients who had a diagnosis of primary large cell lymphoma of the stomach and who had been treated primarily by systemic chemotherapy in our institutions January 1, 1988-December 31, 1998. The patients were divided into two groups by experienced hematopathologists, based on the presence or absence of histologic features suggestive of MALToma, including typical lymphoepithelial lesions and infiltration of characteristic centrocyte-like cells. Disease staging was done according to the AJCC/UICC system with Musshoff modification. The median number of gastric biopsies for each patient was 7 (range, 1-21).

RESULTS

Seventeen patients with and 26 patients without histologic evidence of MALToma were identified. Clinical features were similar between the two groups except that a greater proportion of patients without evidence of MALToma had elevated levels of serum lactate dehydrogenase (50% vs. 12%, P = 0.01). The median duration of follow-up for the 43 patients was 46.5 months (range, 17-124 mos). All patients received standard systemic chemotherapy including anthracyclines or anthracenedione. The response rate was 88.2% for patients with evidence of MALToma and 57.7% for those without (P = 0.03). The 5-year overall survival rate was 80.5% for patients with evidence of MALToma and 48.9% for those without (P = 0.02). Multivariate analysis indicated that response to chemotherapy, disease stage (Stage I and II-1 vs. Stage II-2, III, and IV), and the presence of MALToma features were independent prognostic factors for overall survival.

CONCLUSION

The results of this relatively small study series suggested that the presence of histologic features of MALToma in patients with primary large cell gastric lymphoma might have been associated with a better response to systemic chemotherapy and a better prognosis. Further studies to consolidate this conclusion are necessary.

Outcomes and APACHE II predictions for critically ill patients with acute renal failure requiring dialysis

BACKGROUND

Despite the widespread availability of dialytic and intensive care unit technology, the probability of early mortality in critically ill patients with acute renal failure (ARF) is still high, and the evaluation of the patients' prognosis has been difficult. The Acute Physiology and Chronic Health Evaluation II (APACHE II) score is a reliable indicator of severity of illness and likelihood of survival in critically ill patients with ARF. We have attempted to determine whether the APACHE II scoring system can be used to predict prognosis.

METHODS

A retrospective cohort study evaluated the medical records of 100 consecutive patients in intensive care units with acute renal failure who required dialysis from January 1997 through December 1998.

RESULTS

Of the 100 patients studied, 65 were men and 35 were women. The mean age of survivors and nonsurvivors was 59.4 +/- 20.3 years and 58.3 +/- 20.0 years. The overall mortality rate was 71%. There were no significant differences between survivors and nonsurvivors in age, gender, or indication for dialysis. The cause of death in the majority of patients was related to higher APACHE II score during the 24 hours immediately preceding the initiation of acute hemodialysis, and carry mortality rates exceeding 85% with an APACHE II score of 24 or higher.

CONCLUSION

We conclude that mortality rate for acute renal failure in intensive care unit patients continues to be high. The use of the APACHE II score determined at the time of initiation of dialysis for patients with ARF is a statistically significant predictor of patient survival. There is a significant trend with APACHE II score for outcome.

Thyrotoxic periodic paralysis in a patient abusing thyroxine for weight reduction

Thyrotoxic periodic paralysis is a rare endocrine disorder most prevalent among individuals of Asian descent that presents as proximal muscle weakness, hypokalemia, and signs of hyperthyroidism. We present an unusual patient with previous normal thyroid function who had abused thyroxine as antiobesity pills and developed periodic paralysis affecting the upper and lower limbs.

Keratometric astigmatism after cataract surgery using small self-sealing scleral incision

BACKGROUND

To evaluate the corneal refractive changes after a small self-sealing scleral wound.

METHODS

A 4 mm self-sealing scleral tunnel incision and implantation of a foldable intraocular lens were adopted during phacoemulsification. A retrospective review of 48 consecutive isolated eyes in 48 patients was performed to assess the postoperative corneal refractive change. Keratometric readings were recorded for 3 months following surgery.

RESULTS

At one week postoperatively there was a -0.29 +/- 1.02 (standard deviation) change of Naeser's polar value (against-the-rule shift) in the cylinder keratometry. The cylinder had with-the-rule shift and recovered to the preoperative state at one month postoperatively. The change of Naeser's polar value at the third postoperative month was 0.05 +/- 0.80 (with-the-rule shift) compared with the preoperative polar value. The change of astigmatism at the third postoperative month was -0.38 +/- 0.74 (Diopters) using simple subtraction and -1.01 +/- 0.58 (Diopters) using the Jaffe vector analysis. The axis of astigmatism exhibited a mild against-the-wound shift at 1 week and a gradual with-the-wound shift afterwards.

CONCLUSION

The low induced astigmatism, early recovery of corneal curvature and no direct damage to the cornea support the concept and justify the use of a small self-sealing scleral tunnel incision during cataract surgery.

Methylation of the p15(INK4B) gene in myelodysplastic syndrome: it can be detected early at diagnosis or during disease progression and is highly associated with leukaemic transformation

To investigate the time sequence of occurrence of p15(INK4B) gene methylation in myelodysplastic syndrome (MDS) and its correlation with leukaemic transformation and survival of patients, the methylation status of the p15(INK4B) promoter region was analysed in 50 patients and was serially studied in 22 of them. Of the 50 patients, 17 (34%) showed p15(INK4B) gene methylation, first demonstrated at diagnosis or during follow-up. When FAB subtypes at the time of study were used in the analysis, the incidence of (p15INK4B) methylation in each risk group of MDS remained stable throughout the course: 0% for low-risk MDS [refractory anaemia (RA) and RA with ring sideroblasts] and from 23% at diagnosis to 30% for high-risk MDS [RA with excess of blasts (RAEB), RAEB in transformation and chronic myelomonocytic leukaemia] respectively. The incidence of p15(INK4B) methylation rose to 60% at initial study and, finally, to 75% in cases of acute myeloid leukaemia (AML) evolved from MDS. Most patients (69%) with p15(INK4B) methylation showed disease progression to AML; it could be detected before, at the time or after the diagnosis of leukaemic transformation. p15(INK4B) methylation in MDS patients implicated a shorter survival time in univariate analyses, but its prognostic significance disappeared in multivariate analyses. In conclusion, p15(INK4B) methylation can be detected early at the diagnosis of MDS or acquired during disease progression. It may play an important role in the pathogenesis of some high-risk MDS and is related to leukaemic transformation of MDS.

17 beta-estradiol inhibits tumor necrosis factor-alpha-induced nuclear factor-kappa B activation by increasing nuclear factor-kappa B p105 level in MCF-7 breast cancer cells

Tumor necrosis factor-alpha (TNF-alpha) exerts many cytological effects on a wide range of cells. TNF-alpha can activate nuclear factor-kappa B (NF-kappa B). Activation of NF-kappa B by TNF-alpha mediates many functions of TNF-alpha. The NF-kappa B inhibitor, I kappa B alpha, negatively regulates the activity of NF-kappa B. In MCF-7 cells (an estrogen and TNF-alpha receptor positive cell line), treatment with 17 beta-estradiol (E(2)) inhibited TNF-alpha-induced NF-kappa B DNA binding activity in the gel retardation assays. But, the level of the I kappa B alpha and the TNF-alpha receptor, TNF-R1, were not obviously affected. The NF-kappa B precursor, NF-kappa B p105, has been shown to be associated with NF-kappa B in the cytoplasm and efficiently blocks its nuclear translocation and activation. Treatment of MCF-7 cells with E(2) increased the level of NF-kappa B p105 protein. The anti-estrogen, 4OH-tamoxifen, treatment inhibited E(2)-induced NF-kappa B p105 expression. Our findings indicate that NF-kappa B p105 plays a role in modulating the functions of TNF-alpha in the estrogen receptor positive breast cancer cells.

Comparison of antimicrobial susceptibility of Citrobacter freundii isolates in two different time periods

Citrobacter freundii was first identified in 1932, since then it has been reported to cause a variety of infections in aged, immunocompromised, and debilitated patients. With the use of broad-spectrum antibiotics, C. freundii has become increasingly resistant to antimicrobial agents. In order to determine the chronological changes in susceptibility and current susceptibility status of C. freundii, we compared the antimicrobial susceptibility of C. freundii in two different time periods, from 1987 to 1988 and from 1997 to 1998. In both time periods, 61 isolates of C. freundii were randomly selected for study from all clinical isolates at National Taiwan University Hospital. The minimum inhibitory concentrations and susceptible rates of 15 antimicrobial agents were compared, and it was found that most C. freundii isolates were resistant to anti-pseudomonal penicillins, first, second, and third generation cephalosporins, gentamicin, tobramycin, and aztreonam. The results indicate that the susceptible rates of C. freundii to aminoglycosides and ciprofloxacin decreased markedly during the period from 1987 to 1998. Cefepime, cefpirome, imipenem, and meropenem remained the most active agents against C. freundii.

Acute respiratory distress syndrome following intrathecal methotrexate administration: a case report and review of literature

Acute Respiratory distress syndrome (ARDS) is a rare complication following intrathecal (IT) injection of methotrexate (MTX) in adult acute lymphoblastic leukemia (ALL) patients. A 19-year-old man with ALL developed strikingly acute respiratory failure during central nervous system (CNS) prophylaxis with IT MTX administration and cranial irradiation. Histopathologic study of the lungs revealed a pattern of diffuse alveolar damage with interstitial cellular infiltration. His symptoms were relieved soon following treatment with corticosteroids and the pulmonary infiltrates resolved gradually. Pulmonary symptoms did not recur as he was continuously treated with oral corticosteroids.

Virulence of Vibrio parahaemolyticus isolated from cultured small abalone, Haliotis diversicolor supertexta, with withering syndrome

Outbreaks of mass mortality among cultured small abalone Haliotis diversicolor supertexta with withering syndrome occurred in May and September 1998 in Kao-Hsiung, Taiwan. Bacterial strains CH-1 and B4 were isolated from the haemolymph of the moribund small abalone using tryptic soy agar supplemented with 3% NaCl and/or thiosulphate citrate bile salt sucrose agar. These two strains were characterized and identified as Vibrio parahaemolyticus on the basis of various biochemical tests. The B4 strain and its extracellular products were virulent to small abalone with LD(50) values of 1.6 x 10(5) colony-forming units and 7.58 microg protein g-1 body weight, respectively.

Quinupristin-dalfopristin resistance among gram-positive bacteria in Taiwan

To understand quinupristin-dalfopristin resistance among clinical isolates of gram-positive bacteria in Taiwan, where this agent is not yet available for clinical use, we evaluated 1,287 nonduplicate isolates recovered from January 1996 to December 1999 for in vitro susceptibility to quinupristin-dalfopristin and other newer antimicrobial agents. All methicillin-susceptible Staphylococcus aureus (MSSA) isolates were susceptible to quinupristin-dalfopristin. High rates of nonsusceptibility to quinupristin-dalfopristin (MICs, >/=2 microg/ml) were demonstrated for the following organisms: methicillin-resistant S. aureus (MRSA) (31%), coagulase-negative staphylococci (CoNS) (16%), Streptococcus pneumoniae (8%), viridans group streptococci (51%), vancomycin-susceptible enterococci (85%), vancomycin-resistant Enterococcus faecalis (100%), vancomycin-resistant Enterococcus faecium (66%), Leuconostoc spp. (100%), Lactobacillus spp. (50%), and Pediococcus spp. (87%). All isolates of MSSA, MRSA, S. pneumoniae, and viridans group streptococci were susceptible to vancomycin and teicoplanin. The rates of nonsusceptibility to vancomycin and teicoplanin were 5 and 7%, respectively, for CoNS, ranging from 12 and 18% for S. simulans to 0 and 0% for S. cohnii and S. auricularis. Moxifloxacin and trovafloxacin had good activities against these isolates except for ciprofloxacin-resistant vancomycin-resistant enterococci and methicillin-resistant staphylococci. In Taiwan, virginiamycin has been used in animal husbandry for more than 20 years, which may contribute to the high rates of quinupristin-dalfopristin resistance.

High protease activity of Chryseobacterium indologenes isolates associated with invasive infection

In order to understand virulence factors of Chryseobacterium indologenes isolates associated with invasive infection, enzymatic activities and cellular fatty acid profiles of 42 isolates recovered at National Taiwan University Hospital from January 1994 to December 1996 were studied. Among them, 12 blood isolates were considered as invasive and 30 (recovered from urine, sputa, infected burn wounds, and catheter tips) were noninvasive. All isolates showed strong activities of alkaline phosphatase, acid phosphatase, naphthol-AS-BI-phosphohydrolase, and N-acetyl-beta-glucosaminidase, and had no activities for alpha-galactosidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, and alpha-fucosidase. The activities of other enzymes were variable. Thirty-two isolates (76%) had varying degrees of protease activity. Two profiles (profiles I and II) of cellular fatty acids of the isolates were found and profile I predominated. There was no significant difference of distribution of cellular fatty acid profiles and activities of enzymes between invasive and noninvasive isolates, except protease activity which was significantly higher in invasive isolates than that in noninvasive isolates. Protease activity may play an important role in virulence on invasive infections caused by C. indologenes.

Static cytometry identifies hyperdiploid childhood ALL

Hyperdiploid acute lymphoblastic leukemia of childhood has long been identified with a good prognosis. Identification of this subgroup before treatment commences would enable the most appropriate regimen to be selected. Static cytometry permits an assessment of the DNA content of morphologically selected interphase cells. The blast cells from seven retrospective and seven prospective cases were studied and the ploidy levels compared with the bone marrow karyotype. Static cytometry rapidly identified the hyperdiploid karyotype and, as it was performed specifically on blast cells, it also identified the percentage of these blast cells that were hyperdiploid.

Unicentric Castleman's disease associated with hydronephrosis

We describe a patient with an unusual case of unicentric Castleman's disease, which bore a malignant appearance and was located in the pararenal space. She initially presented with hydronephrosis. Two years after surgical removal of the tumor, no recurrence was evident. To our knowledge, only 2 additional cases of this uncommon disease entity associated with hydronephrosis have been reported. Furthermore, our patient was the first to receive conservative surgery. On the basis of our experience, owing to the benign clinical course of this tumor and its excellent response to limited resection, radical surgery may be avoided.