An epidemic of enterovirus 71 infection in Taiwan. Taiwan Enterovirus Epidemic Working Group

BACKGROUND

Enteroviruses can cause outbreaks of hand-foot-and-mouth disease (characterized by vesicular lesions on the hands, feet, and oral mucosa) or herpangina, usually without life-threatening manifestations. In 1998 an epidemic of enterovirus 71 infection caused hand-foot-and-mouth disease and herpangina in thousands of people in Taiwan, some of whom died.

METHODS

We assessed the epidemiologic aspects of this outbreak. Cases of hand-foot-and-mouth disease or herpangina in ambulatory patients were reported to the Taiwan Department of Health by a mean of 818 sentinel physicians. Severe cases in hospitalized patients were reported by 40 medical centers and regional hospitals. Viruses were isolated by 10 hospital laboratories and the department of health.

RESULTS

The sentinel physicians reported 129,106 cases of hand-foot-and-mouth disease or herpangina in two waves of the epidemic, which probably represents less than 10 percent of the estimated total number of cases. There were 405 patients with severe disease, most of whom were five years old or younger; severe disease was seen in all regions of the island. Complications included encephalitis, aseptic meningitis, pulmonary edema or hemorrhage, acute flaccid paralysis, and myocarditis. Seventy-eight patients died, 71 of whom (91 percent) were five years of age or younger. Of the patients who died, 65 (83 percent) had pulmonary edema or pulmonary hemorrhage. Among patients from whom a virus was isolated, enterovirus 71 was present in 48.7 percent of outpatients with uncomplicated hand-foot-and-mouth disease or herpangina, 75 percent of hospitalized patients who survived, and 92 percent of patients who died.

CONCLUSIONS

Although several enteroviruses were circulating in Taiwan during the 1998 epidemic, enterovirus 71 infection was associated with most of the serious clinical manifestations and with nearly all the deaths. Most of those who died were young, and the majority died of pulmonary edema and pulmonary hemorrhage.

Subcutaneous tumors of mice treated with rhodamine-123 and laser irradiation

BACKGROUND

Treatment involving photosensitizers and laser irradiation (LIR) in cancer therapy is known as photodynamic therapy (PDT). The purpose of our study was to assess the therapeutic effect of PDT using rhodamine-123 (Rh123) and LIR on subcutaneous tumors (ST) in mice.

METHODS

Sarcoma-180 cells (1 x 10(7)) were implanted subcutaneously into the breast area of strain Cr1:CD-1-ICR (BR) female mice. Mice bearing ST were treated with Rh123 or LIR alone, or a combination of both, once a day for 3 successive days.

RESULTS

The best therapeutic effect was observed in the group treated with 7.5 mg Rh123 per kilogram of body weight, combined with 75 J/cm2 laser irradiation energy. The group's mortality rate, tumor control rate, mean survival time, and increase in lifespan within 120 days after treatment were 16.7%, 83.3%, 109.4 days, and 135.8%, respectively. The most inhibitory effect on tumor cells was found in the group treated with 15 mg/kg Rh123 and 90 J/cm2 laser irradiation. The biosyntheses of DNA, RNA, and protein in tumor cells of this group was obviously inhibited.

CONCLUSION

PDT with the photosensitizer Rh123 and laser irradiation was therapeutically effective in treating subcutaneous tumors of mice. The tumor cells and the syntheses of DNA, RNA, and protein of the tumor cells in these PDT treated mice were obviously inhibited.

Effects of glycyrrhizae and glycyrrhizic acid on cellular immunocompetence in low-dose gamma-ray irradiated mice

BACKGROUND

For both animals and human beings, it is important to prevent damage from ionizing radiation and to restore immunocompetence following irradiation. The present study was conducted to investigate the effects of glycyrrhizae (GL) and glycyrrhetinic acid (GA) on cellular immunocompetence in low dose gamma-ray-irradiated mice.

METHODS

Six- to 8-week-old ICR strain' Crl:CD-1-ICR (BR) strain male mice, bred in the Institute of Cancer Research, U.S.A., were chosen and divided into four groups. Group A was the normal control. Group B, the experimental control, received 1 Gy of whole body gamma-ray irradiation. Groups C and D, the experimental groups, were treated with 500 mg/kg of GL (orally) and 5 mg/kg body weight of GA (i.p.), respectively, once a day, 5 days a week for 2 weeks after gamma-irradiation. The tested mice were killed, at 6 different intervals to measure their leukocyte and differential counts. Cellular immunocompetence was measured by the 3H-thymidine uptake in each group.

RESULTS

One gray of gamma-ray irradiation had evident inhibition on the leukocyte and differential counts and the cellular immunity of mice. GL and GA could help to restore the decreased leukocyte counts and the cellular immunocompetence in low dose gamma-irradiated mice.

CONCLUSION

GL and GA could help to restore decreased leukocyte counts and the cellular immunocompetence in low-dose gamma-ray-irradiated mice.

Maxillary growth after palatal denudation: an animal experiment

BACKGROUND

Palate surgery at an early age may cause retardation of maxillary growth. The second intention healing of the raw bone surface created on the palate is considered to be the cause of the growth retardation. The animal experiment in this study was designed to evaluate this effect.

METHODS

Four-week-old Sprague-Dawley rats were divided into 3 groups. In the first group, a strip of mucoperiosteum was excised on both sides of the hard palate. A second group of rats received a sham surgery in which bilateral mucoperiosteal flaps were raised and redraped. The third group served as controls with no surgery. Flap elevation with and without excision was performed under an operative microscope to facilitate the delicate manipulation of tissue and to avoid injury to the underlying bone. The animals were killed 11 weeks later and the skulls were prepared for measurements, which included the palatal inter-molar width, maxillary height, and maxillary length.

RESULTS

The results revealed statistically significant decreases in palatal width and maxillary length in the experimental group (excision of mucoperiosteum). No differences were observed in the vertical height of the maxilla.

CONCLUSION

This study confirms that surgically created bone denudation of the palate causes maxillary growth disturbances.

Affinity purification of Schistosoma japonicum glutathione-S-transferase and its site-directed mutants with glutathione affinity chromatography and immobilized metal affinity chromatography

A C-terminally polyhistidine-tagged protein of Schistosoma japonicum glutathione-S-transferase, named as SjGST/His, and its Cys85-->Ser, Cys138-->Ser, and Cys178-->Ser site-directed mutants were prepared and highly expressed in Escherichia coli. Both immobilized metal affinity chromatography (IMAC) and glutathione (GSH) affinity chromatography were used to purify these four enzymes. All of them were purified with equal efficiency by Ni2+-chelated nitrilotriacetic acid agarose gel, but not by GSH Sepharose 4B gel. The protein amounts of wild-type and Cys85-->Ser enzymes purified by the latter gel were three to seven-fold greater than those of the other two enzymes purified by the same gel, while their specific activities were two-fold lower, presumably because of the occurrence of noncovalent aggregation. Both purification methods yielded highly pure enzymes, while there were minor amounts of inter- and intra-disulfide forms in the IMAC purified enzymes except for the Cys85-->Ser mutant. Addition of dithiothreitol to GSH-affinity purified enzymes shifted all of their mass spectra of matrix-assisted laser desorption/ionization-time of flight mass spectrometry toward low molecular-mass regions, while addition of GSH to IMAC purified enzymes shifted the spectra toward high molecular-mass regions. The shift values of wild-type enzyme were larger than those of the three mutants, indicating that the Cys85, Cys138, and Cys178 residues were S-thiolated by GSH during the GSH-affinity purification. This result was confirmed by isoelectric focusing. These findings suggest that IMAC is more efficient than the conventional GSH-affinity system for the purification of SjGST/His enzyme, especially for its mutants and fusion proteins.

In vitro elution of antibiotic from antibiotic-impregnated biodegradable calcium alginate wound dressing

OBJECTIVE

The authors investigated the calcium alginate dressing as a drug-delivery system for the treatment of various surgical infections.

METHODS

Cytotoxicity of the calcium alginate dressing to fibroblasts and HeLa cells was evaluated by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MITT) colorimetric assay. The calcium alginate dressing was mixed with vancomycin, and lyophilized or not lyophilized to form two types of antibiotic dressings. The antibiotic dressings were placed in 2 mL of phosphate buffered saline (PBS) or in PBS containing 0.01% calcium ions, and incubated at 37 degrees C. The PBS was changed daily, and the removed solutions were stored at -70 degrees C until the antibiotic concentration in each sample was determined by high performance liquid chromatography assay.

RESULTS

The results suggested that the antibiotic dressings present no obvious toxic risk to their use as a drug-delivery system. The concentration of vancomycin in each sample was well above the breakpoint sensitivity concentration (the antibiotic concentration at the transition point between bacterial kill. ing and resistance to the antibiotic) for more than 14 days. The release was most marked during the first 48 hours. The concentration of calcium ions in PBS and the lyophilization of the manufacture process of antibiotic dressings prolonged the antibiotic diffusion duration. The diameter of the sample inhibition zone ranged from 10 to 11 mm, and the relative activity of vancomycin ranged from 62.88% to 92.18%.

CONCLUSION

All antibiotic dressings released bactericidal concentrations of the antibiotics in vitro for the period of time needed to treat surgical infections. This study offers a convenient method to meet the specific antibiotic requirement for different patients.

Development of a biodegradable antibiotic delivery system

Antibiotic beads have been used as a drug delivery system for the treatment of various surgical infections. In this study, the copolymer 50:50 poly(DL-lactide):co-glycolide was mixed with vancomycin powder and hot compressing molded at 55 degrees C to form five types of biodegradable antibiotic beads. The beads were placed in 1 mL of phosphate buffered saline and incubated at 37 degrees C. The phosphate buffered saline was changed daily, and the removed buffer solutions were stored at -70 degrees C until the antibiotic concentration in each sample was determined by high performance liquid chromatography system assay. The concentration of vancomycin in each sample was well above the breakpoint sensitivity concentration (the antibiotic concentration at the transition point between bacterial killing and resistance to the antibiotic) for more than 32 days. The release was most marked during the first 48 hours. All copolymer 50:50 poly(DI lactide):co-glycolide biodegradable beads released high concentrations of the antibiotics in vitro for the time needed to treat bone infections (4 to 6 weeks). The diameter of the sample inhibition zone ranged from 6.5 mm to 10 mm, and the relative activity of vancomycin ranged from 12.5% to 100%. Copolymers with low heat of formation temperatures are required for making a controlled release system to prevent antibiotic decomposition, which occurs when using the hot compressing molded method. The rate and duration of release from the antibiotic beads can be adjusted by varying the diameter of the beads. This offers a convenient method to adjust the release rate to meet the specific antibiotic requirements for different patients.

The percutaneous penetration of prostaglandin E1 and its alkyl esters

The percutaneous delivery of PGE1 and its alkyl esters in alcoholic saline solution through hairless mouse skin was compared. The quantification of alkyl esters was based on the same principle as that for PGE1, which was converted to PGB1 to enhance the sensitivity and minimize the interference. Results showed that it was PGE1 that appeared in the receiver compartment for all alkyl esters examined. The flux of all alkyl esters of PGE1 in the same concentration was higher than PGE1 itself at most of saline vehicle with various fractions of alcohol. The maximal flux for a fixed concentration of each alkyl ester appeared at different fractions of alcohol. When the fractions of alcohol was kept constant, the alkyl ester that showed the maximal flux at this concentration appeared to have a longer chain length with increasing the fraction of alcohol. But isopropyl ester deviated from this order. It was concluded that the alkyl ester derivatives promoted the penetration of PGE1 mainly as a result of enhancing the drug partitioning into the stratum corneum. The alcohol fraction that needed to achieve the maximal flux at the same concentration increased with the increase of alkyl chain length, which resulted in the decrease of solubility parameter. It is necessary to optimize the fraction of alcohol in the saline solution in order to achieve the maximal flux at a fixed concentration for these alkyl esters with different alkyl chain length.

High prevalence of impaired fasting glucose and type 2 diabetes mellitus in Penghu Islets, Taiwan: evidence of a rapidly emerging epidemic?

The purpose of this study was to estimate the prevalence of type 2 diabetes and impaired fasting glucose (IFG) in Penghu, Taiwan and compare these estimates with those of the US (NHANES III). Diabetes and IFG (American Diabetes Association criteria, 1997) were assessed among a stratified random sample of 2500 residents of Penghu Islands, Taiwan. The prevalence (age-adjusted to world adult population) of diabetes and IFG were 16.8% (95% CI 15.0-18.6) and 21.0% (95% CI 19.0-23.0), respectively, among Penghu Islanders in Taiwan. Age sex-specific diabetes prevalence ranged from 10.0% in men aged 40-49 years to 29.4% in women aged 60-69 years. Prevalence of IFG ranged from 14.7% in women aged 40-49 years to 30.7% in men aged 50-59 years. Age, body mass index (BMI), and family history of diabetes were each independently associated with both diabetes and IFG. In addition, female gender, apolipoprotein B and triglyceride concentrations were associated with diabetes, and hypertension and apolipoprotein B concentration with IFG. Among persons > or = 40 years in Penghu, Taiwan, the prevalence of diabetes is up to a third higher and the prevalence of IFG is up to three times higher than comparably aged Americans, despite their having a mean BMI 2.2-3.2 kg/m2 lower than Americans. The alarmingly high prevalence of IFG in Taiwan may indicate an emerging diabetes epidemic.

Signaling pathway and pepsinogen secretion in Helicobacter pylori-infected human gastric adenocarcinoma

Although in vitro studies have suggested that Helicobacter pylori not only attaches to cultured cells but also induces signal transduction events in host cells, the underlying mechanism of H. pylori action has yet to be fully investigated. In the present study, a cytotoxin-positive H. pylori was used to infect and examined for its effect on the stimulation of second messengers in human gastric adenocarcinoma (AGS). Results showed that H. pylori increased cytosolic free calcium concentration [Ca2+]i in host cells in a dose-dependent manner. The increase of [Ca2+]i was due to release from the intracellular Ca2+ store as well as entry to the extracellular Ca2+. H. pylori infection on host cells was also found to induce the generations of inositol phosphates, adenosine 3', 5'-cyclic monophosphate, and guanosine 3',5'-cyclic monophosphate, and to stimulate the secretion of pepsinogen.

Causes of death and associated factors among patients with non-insulin-dependent diabetes mellitus in Taipei, Taiwan

A cohort of 766 patients with non-insulin-dependent diabetes mellitus (NIDDM) from a general teaching hospital in Taipei, Taiwan were followed prospectively to assess survival experience and associated risk factors. Data were abstracted from the medical records and additional information was obtained from patients or their closest relatives using a structured questionnaire. Date and cause of death were determined from death certificates. Standardized mortality ratios were calculated by the direct method. Chi2-Square test and Cox's proportional hazard analysis were used to control for potential confounders. During a median follow-up of 3.5 years (range 1 month to 4.6 years), 131 deaths occurred. Of these, 29.8% were due to cardiopulmonary disease (ICD 401-429), 13.0% due to cerebrovascular disease (ICD 430-438), 13.0% due to acute diabetes metabolic complications (250.1, 250.2), and 11.4% due to nephropathy (580-589). Adjusted for age, people with NIDDM had 2.2 (95% CI 1.6-2.9) times the risk of death than members of the general population, and cause-specific standardized mortality ratios were: CPD 4.6, nephropathy 8.8, cerebrovascular disease 1.9, and neoplasm 0.7. Age, fasting plasma glucose, hypertension, and proteinuria were positively and independently associated with all-cause mortality (P < 0.05 for each). Thus, NIDDM patients have higher mortality rates than the general population in Taiwan, and age, fasting plasma glucose, hypertension, and proteinuria are associated with this excess risk. Proper application of available interventions may control these factors with a consequent reduction in mortality. Particular attention is needed to prevent deaths from the acute metabolic complications of diabetes.

Uterine leiomyohibernoma

A uterine leiomyolipoma with a lipomatous component consisting predominantly of brown fat ("leiomyohibernoma") is described.

A nosocomial outbreak of malaria associated with contaminated catheters and contrast medium of a computed tomographic scanner

OBJECTIVE

To identify the risk factors associated with an unexpected outbreak of malaria that occurred among seven patients in a general teaching hospital in Taipei in October 1995.

DESIGN

A three-stage case-control study was conducted to identify risk factors.

PATIENTS

We identified all 7 patients who were diagnosed as malaria cases and 69 controls from those undergoing computed tomography (CT) examination.

METHODS

Malaria was diagnosed by demonstrating the presence of Plasmodium falciparum on either thick or thin blood smears. Clinical characteristics and exposure information were collected from medical records and patient interviews.

RESULTS

The index case was infected by malaria when he visited Nigeria in early September and was diagnosed when he was hospitalized in hospital A in October. Among 10 patients examined with the Imatron scanner after the index case, all 6 who were injected with contrast medium were infected, but none of 4 examined without contrast medium were infected (P=.005).

CONCLUSIONS

This nosocomial outbreak of malaria was most likely due to transmission via a contaminated catheter and contrast medium used for CT scanning. Use of disposable catheters may avoid such nosocomial outbreaks in the future.

Unusual dental injuries following facial fractures: report of three cases

We report 3 cases of unusual dental injuries following facial fractures. The first patient sustained intrusion of a maxillary incisor into the nasal cavity following a mandibular fracture. The tooth dislocated into the pharynx and was found lodged in the piriform fossa during surgery. The second patient sustained intrusion of molars into the maxillary sinus following maxillary and mandibular fractures. His treatment was delayed due to life-threatening hemorrhage. The third case involved ingestion of multiple avulsed teeth into the alimentary tract following severe maxillofacial fractures. Although the diagnosis was made more than a week after the injury, the patient did not suffer any complications as a result of the dental avulsion. The aim of this report is to emphasize the possibility of associated dental injuries in patients with facial fractures. The trauma surgeon should be cognizant of the importance of carrying out a thorough intraoral examination during the initial evaluation. Any missing tooth should be considered as possibly displaced into other tissue compartments, and must be routinely searched for with x-rays of the skull, cervical spine, chest, and abdomen. If full intrusion injury is suspected, further diagnostic investigation with facial computed tomography scanning may be worth while.

Identification of neutral and acidic sphingomyelinases in Helicobacter pylori

We demonstrated for the first time the presence of sphingomyelinase (SMase) in Helicobacter pylori. Activation of SMase has been implicated as the cause of elevation of cellular ceramide levels and consequently of apoptosis. The data indicate that there are two classes of SMase, defined by their optimal pHs and cellular locations, existing in H. pylori. One is an Mg(2+)-dependent membrane-bound enzyme with an optimal activity at pH 7, and the other is an Mg(2+)-independent cytosolic enzyme with an optimal activity at pH 5. Bisalumin, a bismuth salt, was found to inhibit the activities of both forms of SMase regardless of the presence of Mg2+. By Western blot analysis, the membrane-bound SMases of H. pylori and Bacillus cereus were shown to be antigenically related and to have a similar denatured molecular mass of 28 kDa.

[Seroepidemiology of Japanese encephalitis viral infection among 3-6 years old children from mountainous and plains townships located in the northern, central, southern and eastern Taiwan]

In order to evaluate the Japanese encephalitis virus (JEV) vaccination program in rural Taiwan, we conducted a seroepidemiological survey of JEV among rural children 3 to 6 years of age in Taiwan. The children were selected through a systemic sampling following stratification by age of children in 4 selected aboriginal villages and 4 adjacent nonaboriginal villages. The overall vaccine coverage rate for the primary (2 doses) dose was 81.2% (1853/2281) with higher rates (87.7%-87.9%) found among the more recent birth cohort of 3 to 4 years of age. The neutralizing antibody (NT) against JEV was measured with plaque reduction neutralization test (PRNT) using Nakayama strain as the virus. With a positive NT antibody defined as > or = 1:10 dilution of serum yielding more than 50% plaque reduction, the overall JEV NT antibody positive rate among children receiving 3 doses of vaccine was 67%. However, the age-specific positive rates varied significantly with varying ages; the lowest of 47% being among children 4 years of age which was lower than the rates of 68%, 76% and 87% among children of 3, 5 and 6 years of age, respectively. This trend of rising seropositive rates of JEV antibody with increasing age among 4 and 6 years of age was also noted among children who had received no vaccine, suggesting the importance of natural infection among rural Taiwanese children. Despite the high frequency of natural infection, the seropositive rates of JEV antibody still correlated well with the dose of vaccine received, i.e., 67% (1122/1664), 66% (65/97), 33% (4/12) and 40% (19/47) for children receiving 3, 2, 1, and 0 dose of JE vaccines, respectively (P < 0.0001 Chi-square for trend test). When stratified analysis by dose and by type of vaccines was conducted, a significantly higher seropositive rate of JEV NT antibody was noted among children receiving JE vaccine of Beijing type (87%) than children receiving Nakayama type (39%) (p < 0.0001, Chi-square test). Our data indicated that the JEV vaccination, in conjunction with JEV natural infection, has maintained high JEV NT antibody level among rural children of Taiwan.

Cytodiagnosis of a herniated disk presenting as a soft tissue mass. A case report

BACKGROUND

Extraforaminal disk herniation has been recognized with increasing frequency. When the herniated disk (HD) fragment detaches and migrates away from the spinal column, it can be confused with other space-occupying paraspinal lesions.

CASE

A 63-year-old female presented with right leg pain and weakness. A magnetic resonance image showed a right psoas muscle mass. Fine needle aspiration biopsy (FNAB) established a diagnosis of HD.

CONCLUSION

The cytologic appearance of HD is characteristic. When correlated with clinical findings, the diagnosis of HD can be established by FNAB.

Massive intratumor hemorrhage in facial plexiform neurofibroma

BACKGROUND

Plexiform neurofibromatosis is a feature of von Recklinghausen's disease. Head and neck lesions may produce varying degrees of cosmetic and functional deformity. However, life-threatening hemorrhage into facial plexiform neurofibromas has not been previously reported.

METHOD

We report two patients with von Recklinghausen's disease who experienced massive hemorrhage into facial neurofibromas, one following a blunt injury and the other without a known initiating event.

RESULTS

Conservative management did not stop the hemorrhage into facial neurofibromas in either instance. Surgical exploration was mandated for hemorrhage control and evacuation of blood clots. Hemostasis was attained by a combination of hypotensive anesthesia and chromic catgut suture ligatures.

CONCLUSIONS

These case reports demonstrate a potentially lethal complication in patients with facial plexiform neurofibroma. Where a competent and experienced interventional neuroradiologist is not available, surgical exploration should be undertaken to control bleeding.

Vacuolating toxin from Helicobacter pylori activates cellular signaling and pepsinogen secretion in human gastric adenocarcinoma cells

We investigated cellular signaling and pepsinogen secretion in the human gastric adenocarcinoma cell line AGS which was pretreated with the purified vacuolating cytotoxin from Helicobacter pylori. Results indicated that vacuolating toxin increased the levels of inositol phosphates, cytosolic free calcium concentration, adenosine 3',5'-cyclic monophosphate, and phosphorylation of 31 kDa and 22 kDa proteins in the host cells. Moreover, pepsinogen secretion from AGS cells was stimulated with increasing concentrations of cytotoxin. We conclude that besides the H. pylori cytotoxin-induced cellular vacuoles, cytotoxin-stimulated signaling mediators and pepsinogen release are important factors involved in the etiology of chronic active gastritis and peptic ulcer disease.

Recurrence rate and risk factors for urinary calculi after extracorporeal shock wave lithotripsy

PURPOSE

We determined the recurrence rate after extracorporeal shock wave lithotripsy (ESWL*) and evaluated its associated risk factors, such as patient sex and age, volume of daily water intake, related diseases, family history of urinary calculi, number, burden and location of stones, residual stones after ESWL, serum uric acid level before ESWL and so forth.

MATERIALS AND METHODS

We conducted a retrospective study of 841 patients who underwent ESWL for primary treatment of urinary calculi between 1985 and 1987. Charts were reviewed for stone characteristics, outcomes and associated laboratory data. Followup 6 to 9 years later was done by mail and telephone interviews.

RESULTS

Followup data were available for 436 patients (52%). Overall, stones recurred in 51% of the 436 patients at a mean followup of 7.1 years. Late recurrences were common, and were noted in as many as 70% of the patients after 9 years. This rate is greater than what has been previously reported after other treatments. Cox regression analysis indicated that the major risk factors associated with recurrence were male gender (relative risk 1.406, p < 0.05) and multiple stones (relative risk 1.777, p < 0.05).

CONCLUSIONS

The frequent late recurrences support the speculation that ESWL might lead to greater recurrence rates. Therefore, the cost-effectiveness of ESWL versus other modalities for stone removal warrants more long-term evaluation.