Prevalence of infraumbilical adhesions in women with previous laparoscopy

BACKGROUND AND OBJECTIVE

The aim of this study is to evaluate the prevalence of intraabdominal adhesions to the umbilicus following gynecologic laparoscopy through an umbilical incision.

METHODS

A retrospective review was performed of all gynecologic laparoscopic procedures in a private practice setting to identify patients with a repeat laparoscopy who had a history of a previous laparoscopy through an umbilical incision. Patients with a history of other surgeries were excluded. All repeat laparoscopies used a left upper quadrant entry technique where the abdominal cavity was surveyed for adhesions. We also reviewed adverse events attributable to the left upper quadrant entry approach.

RESULTS

We identified 151 patients who underwent a second laparoscopy and had a previous umbilical scar. Thirty-two of the 151 (21.2%) patients with a history of a laparoscopy had evidence of adhesions to the umbilical undersurface. No adverse events or injuries were attributed to the left upper quadrant entry technique.

CONCLUSIONS

Adhesions to the umbilical undersurface occur in 21.2% of patients who have undergone a prior laparoscopy through an umbilical incision. For this reason, we recommend an alternate location for entry in patients with an umbilical scar from a previous laparoscopy.

Comparative analysis of cavity length-dependent temperature sensitivity of GaInNAs quantum dot lasers and quantum well lasers

Self-assembled GaInNAs/GaAsN single-layer quantum dot (QD) lasers, grown using solid source molecular beam epitaxy, have been fabricated and characterized. A high output power of 40.76 mW/facet was obtained from a GaInNAs QD laser with dimensions of 50 × 700 µm(2) at 10 °C. Temperature-dependent measurements were carried out on the GaInNAs QD lasers of different cavity lengths. For comparison, temperature-dependent measurements were also performed on GaInNAs single quantum well (SQW) and triple QW (TQW) lasers. Unlike the relationship between cavity length and T(0) in GaInNAs SQW/TQW lasers, longer-cavity GaInNAs QD lasers (50 × 1700 µm(2)) showed a lower T(0) of 65.1 K, which is believed to be due to non-uniformity of the GaInNAs QD layer. Furthermore, compared to GaInNAs SQW lasers, a significant improvement in temperature sensitivity was observed in the TQW GaInNAs lasers. This is attributed to a reduction in the relative contribution of the Auger recombination current and suppression of heavy-hole leakage in the TQW laser structures.

A survey on the preference for continuing professional dental education amongst general dental practitioners who attended the 26th Asia Pacific Dental Congress

AIMS

To identify the subjects of interest and to examine the modes as well as means of study for continuing professional dental education amongst general dental practitioners who attended the 26th Asia Pacific Dental Congress, 28 May-1 June 2004, Hong Kong.

METHODS

A total of 381 general dental practitioners as the registered conference delegates from Hong Kong, Mainland China and other Asia-Pacific regions were randomly selected for the present survey. The survey was conducted through face-to-face interviews by a group of practising dentists in Hong Kong.

RESULTS

Overall, orthodontics and prosthodontics were the most popular subjects for clinical degree programmes, whilst oral implantology and cosmetic dentistry were the highly preferred subjects for continuing education courses. Concerning the preferred mode of study for degree programmes, the part-time study mode was chosen by 68.3% of the participating dentists. A didactic teaching approach was preferred by most of the participants (81.7%) for postgraduate study. The majority of the interviewees (76.5%) were interested in a proposed clinical degree programme to be offered jointly by The University of Hong Kong and a leading university in the Mainland. Overall, there was no marked difference in the preference for continuing dental education amongst the respondents from Hong Kong, Mainland China and other Asia-Pacific regions.

CONCLUSIONS

The present survey shows the currently preferred specialty areas and subjects for continuing professional dental education amongst the general dental practitioners who attended the 26th Asia Pacific Dental Congress, with didactic teaching as the most preferred mode of study on a part-time basis.

Self-assembled GaInNAs/GaAsN quantum dot lasers: solid source molecular beam epitaxy growth and high-temperature operation

Self-assembled GaInNAs quantum dots (QDs) were grown on GaAs (001) substrate using solid-source molecular-beam epitaxy (SSMBE) equipped with a radio-frequency nitrogen plasma source. The GaInNAs QD growth characteristics were extensively investigated using atomic-force microscopy (AFM), photoluminescence (PL), and transmission electron microscopy (TEM) measurements. Self-assembled GaInNAs/GaAsN single layer QD lasers grown using SSMBE have been fabricated and characterized. The laser worked under continuous wave (CW) operation at room temperature (RT) with emission wavelength of 1175.86 nm. Temperature-dependent measurements have been carried out on the GaInNAs QD lasers. The lowest obtained threshold current density in this work is ∼1.05 kA/cm²from a GaInNAs QD laser (50 × 1,700 µm²) at 10 °C. High-temperature operation up to 65 °C was demonstrated from an unbonded GaInNAs QD laser (50 × 1,060 µm²), with high characteristic temperature of 79.4 K in the temperature range of 10–60 °C.

A review of laparoscopic uterine suspension procedures for uterine preservation

PURPOSE OF REVIEW

The most appropriate surgical approach for uterine preservation still remains the subject of ongoing controversy. Uterine suspension procedures can be performed abdominally, vaginally, or laparoscopically. This article focuses on the three different laparoscopic approaches of uterine suspension for uterine preservation: suspension to the round ligaments; suspension to the uterosacral ligaments; and suspension to the anterior ligament of the sacral promontory. This article reviews the published studies in the literature, analyzes the results, discusses the differences, and compares the different laparoscopic techniques.

RECENT FINDINGS

A review of the literature reveals a paucity of research studies and publications on laparoscopic uterine suspension procedures. All the published studies are small, retrospective case series or case studies. Laparoscopic ventrosuspension using the round ligaments for uterine prolapse has a reported success rate of less than 50%. The ventrosuspension procedure has a very limited role and should not be employed. In comparison, laparoscopic uterine suspension procedures have a reported success rate ranging between 81 and 100%. The newest surgical technique is the laparoscopic sacral colpohysteropexy and there is only one reported case series on this procedure. The reported success rate for the sacral colpohysteropexy is 100%.

SUMMARY

The first surgical option for uterine preservation is uterine suspension to the uterosacral ligaments. If the uterosacral ligaments cannot be identified or the uterosacral ligaments are weak and unusable, then laparoscopic sacral colpohysteropexy is a reliable second option. Uterine suspension to the round ligaments has an unacceptably high failure rate and is not an effective, durable alternative.

Laparoscopic vaginal vault suspension using uterosacral ligaments: A review of 133 cases

The objective of our study was to describe the surgical technique of laparoscopic vaginal vault suspension using the uterosacral ligaments. In addition, we performed a retrospective analysis of this laparoscopic technique on 133 patients with advanced symptomatic vaginal vault prolapse to evaluate the efficacy and durability of this laparoscopic technique. Efficacy and anatomic outcome were assessed by the Baden-Walker halfway scoring system before and after the surgical procedure. Preoperatively, all patients showed evidence of grade 2 or greater prolapse (descent to the level of the hymen). Fifty-one patients (38.4%) had uterovaginal prolapse, and 82 patients (61.6%) had vaginal vault prolapse. The patients were reevaluated at 1, 6, and 12 months postoperatively and yearly thereafter. The postoperative follow-up ranged from 2.0 to 7.3 years. Postoperatively, 116 patients (87.2%) had no recurrence of prolapse, and 17 patients (12.8%) had recurrence of prolapse. The major complication rate was 2.25%. We conclude that laparoscopic vaginal vault suspension is a safe, efficacious, and durable alternative for the management of vaginal vault prolapse.

Smoking cessation among Hong Kong Chinese smokers attending hospital as outpatients: impact of doctors' advice, successful quitting and intention to quit

To identify factors affecting current smokers' intention to quit smoking and factors associated with successful quitting among ex-smokers in Hong Kong. A cross-sectional survey of Chinese patients attending medical and surgical Specialist Outpatient Clinics (SOPCs) of public hospitals in Hong Kong, using a structured questionnaire. Results of the 642 respondents, 21% were current smokers, 9% were ex-smokers and 69% were non-smokers. 74% of the smokers reportedly received quitting advice from doctors. Among the current smokers, past quitting attempts, receiving information from sources other than doctors, believing that doctor's advice was useful, believing that all smokers should quit smoking and a positive attitude towards quitting were associated with intention to quit. Among those who had attempted to quit, being older (aged 50 or above), being retired/unemployed and consuming more than 10 cigarettes per day were associated with successful quitting. We found that advice from doctors on quitting smoking did not have any impact on Chinese smokers quitting or future intention to quit and reflect the inadequacy of advice given by Hong Kong doctors. The predictors of intention to quit and successful quitting identified in the study could be used to design future smoking cessation services.

Safe entry techniques during laparoscopy: Left upper quadrant entry using the ninth intercostal space—A review of 918 procedures

Surgeons performing sophisticated endoscopic operations must be well versed in alternate laparoscopic access methods to address evolving patient expectations and safety requirements. The safety of left upper quadrant laparoscopic entry in patients with prior surgeries and abdominal adhesions was evaluated. Laparoscopic surgery was performed for various indications on patients with prior surgical scars and anticipated risk of adhesions at the primary umbilical port site. All laparoscopies performed from July 1998 through June 2004 were analyzed. Of the 918 laparoscopies, 504 patients (54.9%) were found to have involvement of their umbilicus with adhesions that could have affected the traditional umbilical primary port entry. Left ninth intercostal space was used for Veres needle entry, and the primary trocar was placed in the left upper quadrant space. Of the 504 potentially risky entries, there were two (0.39%) Veres-needle related and zero trocar-related injuries. All surgical procedures were accomplished laparoscopically, and all entries were accomplished by the left upper quadrant entry technique. Therefore left upper quadrant entry technique is a safe and easily learned alternate access technique.

ApoEε4 allele is associated with incidental hallucinations and delusions in patients with AD

Of 135 patients with Alzheimer disease (AD), 56 without psychiatric symptoms at the first visit were followed for a mean period of 51.9 +/- 10.3 months to identify incident psychiatric symptoms. The hazard ratios of ApoE epsilon4 allele in developing psychiatric symptoms were calculated by Cox regression hazard analyses. The presence of the ApoE epsilon4 allele carried a 19.0-fold risk for developing hallucinations and a 3.4-fold risk for delusions.

Microinjection of glutamate into dorsal motor nucleus of the vagus excites gallbladder motility through NMDA receptor - nitric oxide - cGMP pathway

We have reported that both glutamate and nitric oxide (NO) participated in the regulation of gallbladder motility in dorsal motor nucleus of the vagus (DMV). The aim of this study is to investigate the type of receptor in DMV that mediates the excitatory effect of glutamate on gallbladder motility and the correlation between the glutamate and NO. A frog bladder connected with a force transducer was inserted into the gallbladder to record the change of gallbladder pressure. Glutamate (65 mmol L(-1), 100 nL) microinjected into DMV significantly increased the strength of gallbladder phasic contraction. This effect was abolished by ketamine (180 mmol L(-1), 100 nL), the specific N-methyl-d-aspartic acid (NMDA) receptor antagonist, but was not influenced by 6-cyaon-7-nitroquinoxaline-2,3-(1H,4H)-dione (CNQX) (180 mmol L(-1), 100 nL), the non-NMDA ionotropic receptor antagonist. N(G)-nitro-l-arginine-emthyl (l-NAME) (1 mol L(-1), 100 nL), the nitric oxide synthase (NOS) inhibitor, reversed the excitatory effect of glutamate on gallbladder motility. Microinjection of sodium nitroprusside (SNP), the NO donor, into DMV enhanced the gallbladder motility, and this effect was not modulated by ketamine. Microinjection of NMDA (5 mmol L(-1), 100 nL) increased the strength of gallbladder phasic contraction, and this effect was attenuated by methylene blue (100 mmol L(-1), 100 nL), the soluble guanylate cyclase inhibitor. These results suggest that glutamate regulate the gallbladder motility through the NMDA receptor - NO - cGMP pathway in DMV.

Laparoscopic suburethral sling procedure

STUDY OBJECTIVE

To describe the technique of laparoscopic suburethral sling and discuss patient satisfaction and subjective continence rates over 7 years.

DESIGN

Retrospective analysis (Canadian Task Force classification III).

SETTING

Private practice.

PATIENTS

Sixty-three consecutive patients.

INTERVENTION

Laparoscopic sling procedure using either autologous or donor fascia.

MEASUREMENTS AND MAIN RESULTS

The space of Retzius is entered laparoscopically. Then from a vaginal approach, a small midline vertical incision is made below the urethra, and vaginal epithelium is dissected off underlying periurethral and paravesical fascia. Material for the sling is passed underneath the urethra and secured laparoscopically to Cooper's ligaments bilaterally. Over 7 years, 63 laparoscopic suburethral sling procedures were performed. Overall, patients reported 88.9% satisfaction rate and 81.0% subjective continence rate.

CONCLUSION

The laparoscopic approach is an acceptable alternative to other suburethral sling procedures.

RT-PCR detection of the expression of the polymerase gene of a novel reptilian herpesvirus in tumor tissues of green turtles with fibropapilloma

An alpha-herpesvirus has recently been associated with green turtle fibropapilloma (FP). To further understand the etiological role of this newfound green turtle herpesvirus (GTHV) in the pathogenesis of FP, expression of GTHV polymerase ( pol) gene was determined in tumors and normal-appearing nontumor tissues and organs from five green turtles suffering multiple fibropapillomas, using reverse transcription-polymerase chain reaction (RT-PCR). Amplification of RNA prepared from tumor tissues evidenced the substantial expression of GTHV DNA pol gene in all specimens tested (15/15). However, GTHV pol gene expression in normal-appearing tissues and organs of affected animals was limited (4/45), and GTHV mRNA was detected only in periorbital tissue (1/2), gall bladder (2/5) and lung (1/5) by nested RT-PCR. By contrast, RT-PCR evaluation of RNA isolated from non-tumored turtles revealed undetectable expression of this herpesvirus gene. cDNA sequence analysis revealed that GTHV gene sequences were identical in different tumors. Our data represent the first evidence of the replication of this putative turtle herpesvirus in affected green turtles and fibropapilloma tissues are always active sites of GTHV mRNA synthesis. These findings extend and substantiate the pathogenic association of GTHV with FP.

Structural and biochemical evidence of mitochondrial depletion in pigs with hypertrophic cardiomyopathy

Pig hearts with naturally occurring hypertrophic cardiomyopathy (HCM) were isolated to investigate the effects of mitochondrial deficiency at biochemical and molecular levels. Enzyme activities of mitochondrial-encoded cytochrome c oxidase and NADH dehydrogenase in the HCM hearts (n=12) were lower than that in the controls (n=12) by 41+/-29% (P<0.01) and 43+/-21% (P<0.001), respectively. Additionally, Southern blot analysis was conducted to quantify the relative amount of mitochondrial DNA (mtDNA) from the HCM and controls. The relative amount of mtDNA in the HCM hearts was significantly 57+/-19% (P<0.001) lower than that in the controls. Both mitochondrial enzyme deficiency and mtDNA depletion were significantly correlated with the degree of cardiac hypertrophy judged based on the ratio of heart/body weight. In conclusion, our results reveal that a secondary effect of tissue-specific mtDNA depletion and mitochondrial dysfunction is in response to the HCM.

Laparoscopic appendectomy

STUDY OBJECTIVE

To evaluate the effectiveness of laparoscopic appendectomy in women with chronic pelvic pain and to identify histopathology of the appendix.

DESIGN

Retrospective review over 6.5 years (Canadian Task Force classification II-3).

SETTING

Laparoscopic center and community hospital.

PATIENTS

Three hundred seventeen women.

INTERVENTION

Laparoscopic appendectomy in conjunction with other procedures.

MEASUREMENTS AND MAIN RESULTS

Of 317 patients who underwent appendectomy, 14 (4.4%) had involvement of the appendix with endometriosis, 12 (3.78%) had early acute appendicitis, 4 (1.26%) had carcinoid tumors of the appendix, 2 (0.63%) had a large mucocele, and 1 (0.9%) each had Enterobius vermicularis infection, benign neuroma, and mucinous cystadenoma. Seventy-eight women (24.6%) had obliteration of the appendiceal lumen and 22 (6.93%) had entrapping fibrous adhesions. Thirty-two patients (10%) reported relief of chronic pelvic pain in the absence of other pathology just by having diagnostic laparoscopy with appendectomy.

CONCLUSION

The appendix is a key organ in the evaluation of undiagnosed chronic pelvic pain.

Minimally invasive management of urinary incontinence

Stress urinary incontinence is defined as the loss of urine at the time of an increase in abdominal pressure in the absence of a detrusor contraction. A nearly 50% prevalence of urinary incontinence in women and estimated treatment costs of more than 10 billion US dollars annually in the United States warrant an effective, successful and minimally invasive treatment. Nearly 200 different operations have been described in the literature, with cure rates reported ranging from 40% to 95%, clearly suggesting that the optimal surgical procedure has yet to be developed. Genuine stress urinary incontinence can result from either hypermobility of the bladder neck and proximal urethra or intrinsic sphincteric deficiency, which may occur alone or in combination with anatomic defects. In reviewing the recent literature and surgical modalities we present our opinion on minimally invasive surgical management of urinary incontinence.

Clinical characteristics of Group G streptococcal bacteremia in Taiwan

The results of this retrospective study showed that Group G streptococcal bacteremia was an acute febrile disease with low mortality. Most patients were > 60 y old but there was a strong association between age < 60 y and malignancy. Cases clustered in summer and the most common port of entry was the skin.

Complementary signaling pathways regulate the unfolded protein response and are required for C. elegans development

The unfolded protein response (UPR) is a transcriptional and translational intracellular signaling pathway activated by the accumulation of unfolded proteins in the lumen of the endoplasmic reticulum (ER). We have used C. elegans as a genetic model system to dissect UPR signaling in a multicellular organism. C. elegans requires ire-1-mediated splicing of xbp-1 mRNA for UPR gene transcription and survival upon ER stress. In addition, ire-1/xbp-1 acts with pek-1, a protein kinase that mediates translation attenuation, in complementary pathways that are essential for worm development and survival. We propose that UPR transcriptional activation by ire-1 as well as translational attenuation by pek-1 maintain ER homeostasis. The results demonstrate that the UPR and ER homeostasis are essential for metazoan development.

TGFbeta2 in corneal morphogenesis during mouse embryonic development

To examine the roles of TGFbeta isoforms on corneal morphogenesis, the eyes of mice that lack TGFbetas were analyzed at different developmental stages for cell proliferation, migration and apoptosis, and for expression patterns of keratin 12, lumican, keratocan and collagen I. Among the three Tgfb(-/-) mice, only Tgfb2(-/-) mice have abnormal ocular morphogenesis characterized by thin corneal stroma, absence of corneal endothelium, fusion of cornea to lens (a Peters'-like anomaly phenotype), and accumulation of hyaline cells in vitreous. In Tgfb2(-/-) mice, fewer keratocytes were found in stroma that has a decreased accumulation of ECM; for example, lumican, keratocan and collagen I were greatly diminished. The absence of TGFbeta2 did not compromise cell proliferation, nor enhance apoptosis. The thinner stroma resulting from decreased ECM synthesis may account for the decreased cell number in the stroma of Tgfb2 null mice. Keratin 12 expression was not altered in Tgfb2(-/-) mice, implicating normal corneal type epithelial differentiation. Delayed appearance of macrophages in ocular tissues was observed in Tgfb2(-/-) mice. Malfunctioning macrophages may account for accumulation of cell mass in vitreous of Tgfb2 null mice.

Phenomenology of obsessive-compulsive disorder in Taiwan

This study was designed to assess the phenomenology, comorbidities, correlation with depressive disorders, and gender differences in obsessive-compulsive disorder (OCD) in Taiwan. Two hundred outpatients who fulfilled the diagnostic criteria of OCD according to DSM-IV were included. Patient characteristics, age at onset, symptom profile, and Axis I comorbidity were recorded. Gender differences, age at onset, and comorbidity of depressive disorders among different subtypes of OCD were compared. The most common obsession was contamination, followed by pathological doubt, and need for symmetry. The most common compulsion was checking, followed by washing, and orderliness compulsions. More men than women presented with the obsession of need for symmetry. Eighty-three (41.5%) subjects had comorbid depressive disorders. Women had more major depressive disorder. Patients with somatic obsessions were more likely to have major depressive disorder. Most clinical characteristics of OCD in Taiwan were similar to that of previous studies in other countries.

Comparison and evaluation of copper complex-containing siloxane polymers as stationary phases for capillary gas chromatography

Two metallomesogenic polymers. P-C11CuC18 and P-C11CuC12 consisting of flexible aliphatic side chains with copper carboxylate complexes have been synthesized on the basis of addition reactions with polysiloxane. The applicability of the prepared columns to the analysis of phthalate esters that are of environmental concern was assessed. For preparation of the capillary column with its wall coated with the metallomesogenic polymer, both static and dynamic methods were employed. Factors affecting the retention and the sample selectivity on both columns were examined. A better separation of phthalates was achieved with P-C11CuC18 than P-C11CuC12. The former phase showed a higher solute-solvent interaction than the latter. With static coating, the wall-coated P-C11CuC18 capillary column (15 m x 250 microm I.D.) showed that the baseline separation of all 14 phthalates could be achieved within 38 min with high reproducibility. The calibration graphs for phthalate ester determination were linear over the range of 10-625 microg ml(-1). The mass detection limits were lower than the ng range based on three times the standard deviation of seven measurements of the lowest peak that could be detected.

A point mutation in the cysteine-rich domain of glycoprotein (GP) IIIa results in the expression of a GPIIb-IIIa (alphaIIbbeta3) integrin receptor locked in a high-affinity state and a Glanzmann thrombasthenia-like phenotype

This article reports a Glanzmann thrombasthenia (GT) patient, N.M., with a point mutation in the third cysteine-rich repeat of beta3-integrin or platelet glycoprotein (GP) IIIa, leading to the expression of a constitutively activated fibrinogen receptor. The diagnosis of GT was based on a severely reduced platelet-aggregation response to a series of agonists and approximately 20% of surface-expressed GPIIb-IIIa. The patient's GPIIb-IIIa constitutively expressed epitopes recognized by antibodies to ligand-induced binding sites (LIBS) and also spontaneously bound the fibrinogen-mimetic antibody, PAC-1. Furthermore, significant amounts of bound fibrinogen were detected on his platelets ex vivo. No signs of platelet activation were observed on sections of unstimulated platelets from N.M. by electron microscopy. Immunogold labeling highlighted the presence of surface-bound fibrinogen but revealed platelet heterogeneity with regard to the surface density. When the patient's platelets were stimulated by thrombin-receptor activating peptide, amounts of surface-expressed GPIIb-IIIa increased and the aggregation response improved, although it failed to normalize. Platelets from N.M. were able to adhere and spread on immobilized fibrinogen. Sequence analysis of genomic DNA from N.M. revealed a homozygous g1776T>C mutation in GPIIIa, leading to a Cys560Arg amino acid substitution. A stable Chinese hamster ovary (CHO) cell line was prepared expressing surface GPIIb-Arg560IIIa. Like platelets from the patient, GPIIb-Arg560IIIa-transfected CHO cells constitutively bound LIBS antibodies and PAC-1. They also showed an enhanced ability to adhere on surface-bound fibrinogen. Overall, these data demonstrate that a gain-of-function mutation can still be associated with a thrombasthenic phenotype even though platelets show spontaneous fibrinogen binding.

Up-regulation of Fas ligand expression by human cytomegalovirus immediate-early gene product 2: a novel mechanism in cytomegalovirus-induced apoptosis in human retina

Human CMV (HCMV) is an important pathogen that causes widespread diseases in immunocompromised individuals. Among the opportunistic HCMV infections, HCMV retinitis is most common in transplant recipients and AIDS patients. It often leads to blindness if left untreated. The question as to how HCMV infection causes retinal pathogenesis remains unresolved. Here, we report that viral immediate-early gene product 2 (IE2), but not IE1, up-regulates the Fas ligand (FasL) expression in HCMV-infected human retinal pigment epithelium cells. Increased secretion of FasL from virally infected cells into cultured medium was observed upon HCMV infection. The capability of such cell-free medium to induce apoptosis of Fas (CD95)-expressing Jurkat cells further implies that Fas-FasL interaction might mediate cell death in the lesion of HCMV retinitis. To support this idea, we observed augmented soluble FasL levels in vitreous from AIDS patients with HCMV retinitis as compared with that from AIDS patients without HCMV infection. In addition, by in situ hybridization and immunohistochemistry, we detected enhanced signals of FasL, the existence of viral IE Ags and apoptotic cells at the same sites in the lesion of HCMV-infected retina. These results strongly suggest that IE2 induction of FasL expression in human retina might be an important event that takes place in the early stage of infection and finally leads to visual loss in individuals affiliated with HCMV retinitis.

2001: Things to come

THIS ARTICLE DISCUSSES elements in the definition of modernity and emerging futurism in neurological surgery. In particular, it describes evolution, discovery, and paradigm shifts in the field and forces responsible for their realization. It analyzes the cyclical reinvention of the discipline experienced during the past generation and attempts to identify apertures to the near and more remote future. Subsequently, it focuses on forces and discovery in computational science, imaging, molecular science, biomedical engineering, and information processing as they relate to the theme of minimalism that is evident in the field. These areas are explained in the light of future possibilities offered by the emerging field of nanotechnology with molecular engineering.

Comparative study of ceftibuten and cefixime in the treatment of complicated urinary tract infections

Between August 1996 and May 1998, a total of 62 patients who had complicated urinary tract infections treated at the Taipei Veterans General Hospital were enrolled into this study. This prospective, randomized, open-labeled trial aimed at comparing the efficacy and safety of ceftibuten and cefixime, prescribed each at a dose of 200 mg twice daily, in treating complicated urinary tract infection. Seventeen patients were later excluded from the analysis because of resistant pathogens (7 patients), uncomplicated urinary tract infection (6), initial culture negative for bacteria (3), and infective endocarditis (1). The remaining 45 patients were categorized into ceftibuten (n=23; mean age, 71.3 years) and cefixime (n=22; mean age, 62.8 years) treatment groups. No significant difference in demographic data and clinical characteristics was found between the 2 groups. The clinical efficacy rate (78.3% vs 77.3%, p=0.9) and bacteriological eradication rate (52.2% vs 63.6%, p=0.08) were similar between the ceftibuten and the cefixime group. Adverse effects caused by ceftibuten treatment included diarrhea and slight elevation of the serum level of liver transaminase in 2 (6.5%) patients. Those caused by cefixime treatment included slight elevation of serum level of liver transaminase in 2 (6.5%) patients and skin rash in 1 (3.2%) patient. All of these adverse effects resolved quickly after the regimen had been completed, and no patient discontinued the regimen because of the adverse effects. The results suggest that oral administration of ceftibuten 200 mg twice daily is as effective and safe as oral administration of cefixime 200 mg twice daily in the treatment of complicated urinary tract infections.

Characteristics of patients with Burkholderia cepacia bacteremia

Burkholderia cepacia has become an important pathogen of infections in immunocompromised and nosocomial patients. The characteristics of 42 episodes of B. cepacia bacteremia in 40 patients admitted to the Taipei Veterans General Hospital between January 1997 and December 1999 were retrospectively analyzed. Factors that adversely influenced the mortality rate included respiratory failure, an unknown infection source, a period in an intensive care unit, and shock. Most of the patients had serious underlying diseases, such as diabetes mellitus, malignancy, congestive heart failure, and chronic obstructive pulmonary disease. The mean time for a positive blood culture was 45 days after admission. The overall mortality rate was 28.6% (12/42), and 44.4% (12/27) of all deaths were directly related to B. cepacia bacteremia. Polymicrobial bacteremia was found in 5 patients. Ceftazidime was the most effective antimicrobial agent in vitro, whereas chloramphenicol, imipenem, and trimethoprim/sulfamethoxazole were less effective alternatives. Appropriate antibiotic therapy was given to 30 patients, most of whom responded to the therapy except for 5 who died despite receiving appropriate treatment. Although B. cepacia infection develops in a relatively small proportion of hospitalized individuals, it has a major impact on morbidity and mortality. In view of the fact that B. cepacia develops resistance to a wide range of antimicrobial agents, ceftazidime and/or trimethoprim/sulfamethoxazole should be the drug of choice for empiric therapy.

Remediation of TCE contaminated soils by in situ EK-Fenton process

The treatment performance and cost analysis of in situ electrokinetic (EK)-Fenton process for oxidation of trichloroethylene (TCE) in soils were evaluated in this work. In all experiments, an electric gradient of 1V/cm, de-ionized water as the cathode reservoir fluid and a treatment time of 10 days were employed. Treatment efficiencies of TCE were evaluated in terms of the electrode material, soil type, catalyst type, and catalyst dosage and granular size if applicable. Test results show that graphite electrodes are superior to stainless steel electrodes. It was found that the soil with a higher content of organic matter would result in a lower treatment efficiency (e.g. a sandy loam is less efficient than a loamy sand). Experimental results show that the type of catalyst and its dosage would markedly affect the reaction mechanisms (i.e. "destruction" and "removal") and the treatment efficiency. Aside from FeSO4, scrap iron powder (SIP) in the form of a permeable reactive wall was also found to be an effective catalyst for Fenton reaction to oxidize TCE. In general, the smaller the granular size of SIP, the lower the overall treatment efficiency and the greater the destruction efficiency. When a greater quantity of SIP was used, a decrease of the overall treatment efficiency and an increase of percent destruction of TCE were found. Experimental results have shown that the quantity of electro-osmotic (EO) flow decreased as the quantity of SIP increased. It has been verified that the treatment performances are closely related to the corresponding EO permeability. Results of the cost analysis have indicated that the EK-Fenton process employed in this work is very cost-effective with respect to TCE destruction.

Association analysis of the 5-HT6 receptor polymorphism C267T with depression in patients with Alzheimer's disease

A significant increase of 267C allele of the 5-HT(6) receptor gene has been reported in patients with Alzheimer's disease (AD). Because a deficit in serotonergic neurotransmission is involved in major depression, we tried to find out whether 267C allele is associated with depressive disorders in AD. A psychiatrist interviewed all AD patients and their caregivers for evidence of depression using a Chinese version of the Standard Clinical Interview for DSM-III-R. The difference in the 5-HT(6) genotype or allele distributions between the AD patients with depressive disorders (n = 25) and those without (n = 120) was not significant.

Laparoscopic ureteroureteral anastomosis on the distal ureter

Repair of ureteral injury involving the distal ureter traditionally required laparotomy. Ureteroureteral anastomosis is not usually advocated due to technical difficulties and poor outcomes. Laparoscopy overcomes these difficulties and allows correction of distal ureteral injuries.

Histidine-functionalized silica and its copper complex as stationary phases for capillary electrochromatography

A histidine-functionalized silica was prepared by covalent bonding of the functional groups to silane-treated silica gel. Conversion of functional groups was confirmed by infrared (IR) spectra, elemental analysis, and potentiometry. The functionality of the silica gel is 0.293 mmol g(-1). The coordination behavior of the histidine-functionalized silica was investigated by metal capacity and electron paramagnetic resonance (EPR). EPR measurements at different copper loadings were made. The results showed that the copper histidine complex might be distorted tetragonal. Both histidine-functionalized silica and its copper complex were employed as stationary phases for packed capillary electrochromatography (CEC). Electrical current was found helpful for evaluating the properties of frit construction and the stationary phase packing. Test samples include neutral compounds, inorganic anions and organic anions. Factors influencing the separation behavior have been studied. With copper-histidine functionalized silica under the condition of citrate buffer (10 mM, pH 4.0) and applied voltage of -20 kV, the separation of benzoic acid, D- and L-mandelic acid, phthalic acid and salicylic acid could be achieved within 12 min. The column efficiency for these acids was more than 1.2 x 10(5) plates m(-1), except salicylic acid.

Correlation of panic attacks and hostility in chronic schizophrenia

The aim of this study was to investigate the relationship between panic attacks and hostility in patients with chronic schizophrenia. Thirty-two patients with a minimum 2-year history of treatment for schizophrenia were interviewed. The patients took mood stablizers lithium, carbamazepine and valproate adjunctively for hostility and anger attacks. Panic attacks were defined by Structure Clinical Interview of DSM-IV. Severity of psychopathology was assessed by the Hamilton Depression Rating Scale (HDRS) and Brief Psychiatric Rating Scale (BPRS). Functional level was assessed by the Global Assessment of Functioning Scale (GAF). Eight (25%) patients met the diagnostic criteria for panic attacks (DSM-IV) with affective symptoms including hostility and sudden spells of anger. Their HDRS scores were significantly higher (P < 0.01), and GAF scores were significantly lower (P < 0.05) than those of patients without panic attacks. Patients with panic attacks displayed significantly higher hostility in the score of the BPRS (P = 0.01). Those who received higher doses of neuroleptics were more likely to be considered hostile. Multivariate analysis revealed that panic attacks were correlated with more severe depression, greater hostility and lower GAF scores. The results suggest that increased hostility and anger spells may be symptoms of panic attacks, which are overlooked by psychiatrists.

Stationary phases for capillary electrophoresis and capillary electrochromatography

An overview of the most recent developments in column technology employed in capillary electrophoresis (CE) and capillary electrochromatography (CEC), mainly for the separation of small molecules and ions, is presented. Particular emphasis is laid on permanent coating. The wall modification methods in CE include covalent modification, adsorbed coatings and polymeric coatings, while those in CEC include packed columns, open-tubular columns and fritless columns. A short discussion on the characterization and selectivity of the bonded phases is also given.

[Effect of nucleus raphe obscurus on myoelectric activity of sphincter of Oddi in rabbits]

The aim of the present study was to investigate the role of nucleus raphe obscurus (NRO) in regulating the motility of sphincter of Oddi (SO). After fasting about l8~24 h, the rabbits were anesthetized with urethane (1.0 g/kg), and the myoelectric signals of SO were induced by a pair of copper electrodes inserted into the subsera. The results of microinjection of various drugs into NRO are as follows. After glutamate (340 mmol/L, 0.1 microl) was injected, activity of SO was excited. With microinjection of GABA (1 mol/L,0.1 microl), the spike burst of SO was inhibited. Following microinjection of ketamine (180 mmol/L, 0.1 microl), a kind of N-methyl-D-aspartate (NMDA) receptor antagonist, SO motility was inhibited and the effect of glutamate was abolished. Injection of 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) (2 mmol/L, 0.1 microl), a non-NMDA receptor antagonist, also excited the myoelectric activity of SO, but did not inhibit the effect of glutamate. The effect of glutamate was abolished by intravenous injection of atropine (0.2 mg/kg) or bilateral vagotomy, but not by injection of phentolamine (1.5 mg/kg) or propronalol (1.5 mg/kg), or by transection of the spinal cord. The above results indicate that NRO mediation of SO activity is due to the effect of glutamate on the NMDA receptors in the nucleus, the output of which is sent through vagal nerve and peripheral M cholinergic receptor to exert excitation of gallbladder motility.

Cross-cultural implementation of a Chinese version of the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) in Taiwan

BACKGROUND

There are no published reports of cross-cultural equivalence and interrater reliability at the level of individual symptom items assessed by a semi-structured clinical interview employing operationalised clinician ratings.

AIMS

To assess the cross-cultural clinical equivalence and reliability of a Chinese version of the World Health Organization Schedules for Clinical Assessment in Neuropsychiatry (SCAN).

METHOD

UK-US and Taiwanese groups of psychiatrists used Chinese and English transcripts of videotape interviews of Taiwanese patients to discuss cross-cultural issues and ratings of SCAN items. Item ratings were compared quantitatively individually and pooled by SCAN section.

RESULTS

Chinese equivalents were found for all SCAN items. No between-group differences were found for most individual items, but there were differences for some scaled items. Average agreement between the two groups was 69-100%.

CONCLUSIONS

Cross-cultural implementation based on SCAN in Taiwan appears valid.

Investigation of an outbreak caused by methicillin-resistant Staphylococcus aureus in a cardiovascular surgery unit by ribotyping, randomly amplifed polymorphic DNA and pulsed-field gel electrophoresis

An outbreak caused by rapid spread of methicillin-resistant Staphylococcus aureus (MRSA) in an intensive care unit for cardiovascular surgery was investigated by phenotypic and genotypic methods. Fourteen isolates were collected during a 2-month period from clinical and environmental specimens in the unit recently re-opened after reconstruction. The isolates were tested for antibiotic susceptibility patterns and genotyped by automated ribotyping, randomly amplified polymorphic DNA-PCR (RAPD) analysis and pulsed-field gel electrophoresis (PFGE). Automated ribotyping applying EcoRI digestion proved to be of no value in separating the isolates. In contrast, PFGE grouped the isolates into four clusters different from the reference strain. These results fully correlated with the antibiograms. Twelve of the isolates were grouped into two clonally related clusters. RAPD analyses grouped the isolates into five clusters. Except for two isolates of one patient, which had different RAPD patterns, PFGE and RAPD analyses presented very similar results. The results verified the usefulness of PFGE in studies of MRSA epidemics. A combination of these two methods reduces the time to identification of an outbreak and increases the accuracy in detection of intraspecies differences.

MK/T-1, an immortalized fibroblast cell line derived using cultures of mouse corneal stroma

PURPOSE

Immortalized cell lines representing fibroblast cells from corneal stroma would facilitate studies of corneal cell biology and injury response.

METHODS

Primary cultures of cells derived from mouse corneal stroma were transfected with a human telomerase reverse transcriptase (hTERT) expression construct to maximize chances of cellular immortalization. A resulting cell line was analyzed for telomerase activity, cell growth characteristics, senescence and gene expression patterns. Specific responses to transforming growth factor beta (TGF-beta) were also analyzed.

RESULTS

An immortalized cell line was derived and was named MK/T-1. MK/T-1 cells show no signs of cellular senescence or transformation at over 100 passages. Telomerase activity was significantly higher in MK/T-1 cells as compared to the parental cell cultures. However, relative telomere length (RTL) in the MK/T-1 and parental cells was not significantly different. Senescence associated beta-galactosidase (SA-beta-Gal) activity was not detected in late passage MK/T-1 cells while the parental cells had already upregulated SA-beta-Gal at high levels by passage 9. The MK/T-1 cells express vimentin, tubulin, lumican, mimecan, decorin and collagen I, but not keratocan. Exposure of the MK/T-1 cells to TGF-beta induces the expression of smooth muscle alpha-actin (ASMA), the activation of MAP Kinase (p38-MAPK) and morphological changes consistent with cytoskeletal reorganization.

CONCLUSIONS

MK/T-1 cells represent an immortalized fibroblast cell line derived using cultures from corneal stroma cell preparations. Expression of hTERT may contribute to immortalization of the MK/T-1 cells by a mechanism other than increases in RTL. MK/T-1 cells may be a useful model in which to study the responses of corneal fibroblast cells to cytokines and other diverse environmental factors in vitro.

Kinetics of methyl t-butyl ether cometabolism at low concentrations by pure cultures of butane-degrading bacteria

Butane-oxidizing Arthrobacter (ATCC 27778) bacteria were shown to degrade low concentrations of methyl t-butyl ether (MTBE; range, 100 to 800 microg/liter) with an apparent half-saturation concentration (K(s)) of 2.14 mg/liter and a maximum substrate utilization rate (k(c)) of 0.43 mg/mg of total suspended solids per day. Arthrobacter bacteria demonstrated MTBE degradation activity when grown on butane but not when grown on glucose, butanol, or tryptose phosphate broth. The presence of butane, tert-butyl alcohol, or acetylene had a negative impact on the MTBE degradation rate. Neither Methylosinus trichosporium OB3b nor Streptomyces griseus was able to cometabolize MTBE.

Occurrence of fumonisin B1 in maize imported into Taiwan

Samples of maize imported into Taiwan during 1997-1998 were collected and analyzed for the presence of fumonisin B1 (FB1) using high performance liquid chromatography. Eight (6.8%) of 118 samples were found to contain FB1 (334-1614 microg kg(-1)). The frequency of FB1 found in maize samples imported from Australia was 20%, followed by Thailand (10%), and USA (5.1%). In analyzing the distribution pattern, it was found that 93.2% of the samples had FB1 concentrations below 100 microg kg(-1), and only 3.4% (or four samples) were in excess of 300 microg kg(-1).

Risk factors of catheter-related infections in total parenteral nutrition catheterization

BACKGROUND

The use of central venous catheter for administration of total parenteral nutrition (TPN) is a risk factor of catheter-related infections (CRIs) that are associated with increased morbidity and mortality, prolonged hospitalization, and increased medical costs. The purpose of this study is to evaluate the risk factors of CRIs in patients with administration of TPN.

METHODS

A total of 1134 patients receiving TPN between January, 1996 and December, 1998 were studied. The category of infection included definite catheter-related bloodstream infection (CR-BSI), probable CR-BSI, and insertion site infection. Statistical analysis of risk factors was performed.

RESULTS

A total of 131 episodes of CRI occurred, representing an infection rate of 11.46%. Ninety-three episodes (8.1%) had probable CR-BSI, 13 episodes (1.1%) had definite CR-BSI, and 25 episodes (2.2%) had insertion site infection. Duration of TPN infusion and frequency of catheter insertion showed statistically significant difference by logistic regression multivariate analysis. The isolated organisms were in sequence of coagulase-negative Staphylococci (19.4%), Staphylococcus aureus (17.2%) and Candida albicans (14.4%).

CONCLUSIONS

Risk factors influencing the occurrence of CRI in TPN administration were multifactorial; however, duration of TPN infusion and frequency of catheter insertion were the main factors in our study.

Incineration of paper sludge in a prototype vortexing fluidized bed combustor

All experiments were carried out in a prototype vortexing fluidized bed combustor (VFBC). The dimension of the combustion chamber is 0.7 x 1.4 x 2 m, and the freeboard section is 1 m i.d. and 4 m in height. Paper sludge was used as the feeding material. Two types of coal particles were employed as the supplementary fuel. In order to understand the characteristics of the VFBC system for paper sludge incineration, the effect of various operating parameters, such as the primary airflow, excess air ratio, and secondary airflow rates, on temperature distribution, ash elutriation, combustion efficiency, and pollutant emissions were investigated.

Upregulation of inducible nitric oxide synthase and cytokine secretion in peripheral blood monocytes from pulmonary tuberculosis patients

SETTING

Peripheral blood monocytes (PBM) are the main source of alveolar macrophages, which have an upregulation of inducible nitric oxide synthase (iNOS) in pulmonary tuberculosis (TB). TNF-alpha and IL-1 beta are thought to be involved in the immune response to mycobacterial infection.

OBJECTIVE

To identify whether iNOS expression and cytokine release of PBM are upregulated and have a connection in TB infection.

DESIGN

The expression of iNOS immunoreactivity on PBM from TB patients and normal subjects was measured by loading with anti-macrophage iNOS polyclonal primary antibody analyzed by flow cytometry. Expression of iNOS mRNA in PBM was detected by RT-PCR. The spontaneous generation of nitrite and cytokines (IL-1 beta and TNF-alpha) by cultured monocytes was also determined.

RESULTS

Compared to normal subjects, iNOS immuno-reactivity, the capacity for spontaneous nitrite generation and the level of TNF-alpha or IL-1 beta secretion of PBM were significantly higher in TB patients. The amount of nitrite, TNF-alpha and IL-1 beta released from PBM of TB patients was inhibited by NG-monomethyl-L-arginine (L-NMMA), a competitive inhibitor of NOS. The level of iNOS immunoreactivity on PBM was highly correlated with nitrite generation both in all the subjects studied and in TB patients alone. Spontaneous TNF-alpha production showed a stronger correlation with nitrite production than with IL-1 beta.

CONCLUSION

The NO and cytokine synthase activities of monocytes appear to be concomitantly upregulated in response to mycobacterial infection. The enhanced NO generation by monocytes in TB patients may play an autoregulatory role in amplifying the synthesis of pro-inflammatory cytokines.

Comparison of aerobic denitrification under high oxygen atmosphere by Thiosphaera pantotropha ATCC 35512 and Pseudomonas stutzeri SU2 newly isolated from the activated sludge of a piggery wastewater treatment system

AIMS

This study compares the ability of Thiosphaera pantotropha ATCC 35512 and the newly isolated Pseudomonas stutzeri SU2 to perform aerobic denitrification.

METHODS AND RESULTS

Nitrate-supplemented basal medium in airtight crimp-sealed serum bottles containing an atmosphere of 92% oxygen was inoculated with Ps. stutzeri SU2 or T. pantotropha and incubated at 30 degrees C. During the 92-h incubation period, aerobic denitrification by Ps. stutzeri SU2 (NO3(-) - N removal 99.24%) was more efficient than that by T. pantotropha (NO3(-) - N removal 27.29%).

CONCLUSION

Pseudomonas stutzeri SU2, which was isolated from the activated sludge of a sequencing batch reactor treating piggery wastewater, rapidly reduced the nitrate to nitrogen gas without nitrite accumulation. The nitrate removal rate of SU2 was 0.032 mmol NO3(-) - N g cell-1 h-1 after 44 h incubation.

SIGNIFICANCE AND IMPACT OF THE STUDY

Pseudomonas stutzeri SU2 can be used in a full-scale sequencing batch system for efficient in situ aerobic nitrate removal from piggery wastewater.

Anticoagulation therapy for radiation-induced myelopathy

OBJECTIVE

To report the use of heparin and enoxaparin for radiation-induced myelopathy.

CASE SUMMARY

A 48-year-old White woman with presumed metastatic lung cancer presented with worsening numbness and weakness of both legs. The neuro-oncology service was consulted and determined that the symptoms were consistent with radiation-induced myelopathy. The patient briefly responded to steroid treatment. A trial of intravenous heparin therapy was initiated by the primary team and managed by the clinical pharmacy services. Her symptoms improved when heparin was begun. She was able to walk and was subsequently discharged home on enoxaparin.

DISCUSSION

Spinal cord injury is one of the known adverse effects of radiation. The onset of symptoms can be acute or delayed. The clinical signs and symptoms of delayed neurologic injury are related to the narrowing and occlusion of the vessel lumen, ischemia, edema, and cell death in the surrounding nervous tissue. Treatment often consists of corticosteroids and/or hyperbaric oxygen; however, the outcomes are often disappointing. In addition to the inhibition of serum protein-mediated coagulation, heparin inactivates or prevents the release of mediators of vascular injury inflammation, permeability, and edema. Therefore, patients with radiation-induced spinal cord injury may benefit from anticoagulant therapy.

CONCLUSIONS

Heparin and/or enoxaparin may be considered as potential treatments for patients with radiation-induced myelopathy.

[Clinical study on treatment of exogenous infection caused fever by infantile umbilical paste]

OBJECTIVE

To observe the effect of infantile umbilical paste (IUP) in abating infantile fever.

METHODS

Two hundred and twenty cases were randomly divided into two groups, the 120 cases in Group A were treated with IUP and the 100 cases in Group B treated with compound Aspirin (APC). The effect in abating fever and side-effects were observed.

RESULTS

The total effective rate of the two groups were not statistically different (P > 0.05). But a better effect in abating fever was shown in Group A 4 hrs later (P < 0.01). The effect in patients of age under 1 year was the best.

CONCLUSION

IUP has good effect in abating infantile fever, and it shows no influence on white blood cells, liver and kidney functions.

Meperidine addiction or treatment frustration?

There have been few studies of the psychiatric characteristics of analgesics addiction. The physician's perceptions that patients were addicted to analgesics might be partially attributable to frustration with poor response to treatment. In this retrospective study, we evaluated the medical records of 20 subjects (15 male and 5 female) who were perceived as having addiction to meperidine by general physicians. The most common medical diagnosis among these patients was chronic pancreatitis (7/20). Among them, five had a past history of suicide attempt and three had self-injury behavior during the index admission. The fact that subjects were perceived as being addicted might be attributable to a vicious cycle of the following factors: 1) chronic intractable pain; 2) poor staff-patient relationship; 3) lower pain threshold or tolerance due to anxiety or depression; 4) patients with a history or tendency of substance abuse; 5) placebo use and inadequate analgesics regimen. The findings of this study suggest that the importance of the following diagnostic and treatment procedures in these patients: 1) suicide risk should be evaluated; 2) comorbid psychiatric diseases should be treated; 3) factors that cause a vicious cycle in pain control should be identified; 4) misconceptions of opiate analgesics among medical staff should be discussed; 5) poor staff-patient relationship should be managed aggressively; and 6) "addiction" is a critical diagnosis that should be avoided if possible.

Effects of the type of sintering atmosphere on the chromium leachability of thermal-treated municipal solid waste incinerator fly ash

The sintering process offers an opportunity to combine detoxification and resource recovery for the treatment of municipal solid waste (MSW) incinerator fly ash. However, the chromium (Cr) in the sintered fly ash becomes more readily leachable with increasing sintering time and temperature, thus posing severe threats to the environment and human health when the sintered ash is recycled or reused. This study investigated the enhanced leachability of fly ash containing Cr, by heating the chromium (III) oxide (Cr2O3)-spiked fly ash to 800 degrees C in atmospheres containing air, nitrogen gas (N2), and 5% H2 + 95% N2, respectively. The results indicated that trivalent chromium was converted to its soluble hexavalent form during sintering in the air atmosphere; whereas sintering in a nitrogen atmosphere significantly reduced the leachability of Cr due to lack of oxygen (O2) to oxidize. The effects of the sintering temperature on the total chromium content and the leaching concentration in the toxicity characteristic leaching procedure (TCLP) extract are also discussed.

Analysis of the human lumican gene promoter

The human lumican gene was shown to possess one major transcription start site, resulting in exon 1 of the gene giving rise to the first 74 base pairs (bp) of the 5'-untranslated region. About 1.6 kilobase pairs of upstream promoter sequence were sequenced and analyzed to identify elements responsible for gene expression. No typical TATAA sequence was identified in the vacinity of the transcription start site, but an atypical TATCA sequence residing 41 bp upstream was shown to be necessary for transcription, although it was incapable of supporting transcription by itself. A GC box residing 74 bp upstream of the transcription start site also was essential for the initiation of transcription. Sp3 was identified as the transcriptional activator binding to the GC box. No additional elements that significantly modulated transcription were noted in the promoter sequence analyzed, when using human adult chondrocytes as the cell source for transfection in reporter assays. In contrast, reporter assays carried out in human fetal lung fibroblasts, where lumican expression is deplete, revealed the presence of a repressor element located between 384 and 598 bp upstream of the transcription start site. A GATA-binding site located between bp -386 and -391 was identified as being necessary for repression of transcription. The mouse lumican promoter does not possess an equivalent site, and this may explain why the lumican gene is expressed in fetal murine cartilage but not in fetal human cartilage.

Using buffy coat for reverse transcriptase-polymerase chain reaction in the diagnosis of dengue virus infection: preliminary study

Using reverse transcriptase-polymerase chain reaction (RT-PCR) to detect and type from viremic human serum samples for dengue virus infection is widely used today. However, a few false-negative results were reported due to very low titers of the virus particle in serum samples. As mononuclear cells, macrophages or monocytes are target cells for dengue virus infection, and the replication of virions can be observed in peripheral leukocytes frequently, the amount of virus particle in buffy coat should be higher than those in serum samples. Here, we describe a procedure in which RNA extraction from the buffy coat of a patient with a false-negative serum sample yielded specific viral RNA amplifiable by RT-PCR, thereby providing an alternative choice for the accurate diagnosis of dengue infection.

Preparation and evaluation of an imidazole-coated capillary column for the electrophoretic separation of aromatic acids

An imidazole-coated capillary column for electrophoresis has been prepared by means of organosilanization. With mesityl oxide as neutral marker, the results indicated that the electroosmotic flow of the bonded phase displays a dramatic difference in pH dependence in comparison with that of the bare fused-silica column. The presence of positive charges on the coating surface and the anionic exchange property, due to the cationic property of the imidazole group at pH values below 6, allows the separation of geometric isomers that are very similar in ionic mobility. Separation parameters including buffer composition and concentration, pH, applied voltage, and the influence of other additives were investigated. By using acetate buffer (100 mM, pH 5.2) and an applied voltage of -15 kV with UV detection at 212 nm, the separation of 11 aromatic acids including mono-, di-, tri- and tetra-carboxylic acids could be achieved in less than 14 min. The average plate number was 3 x 10(5)/m. With acetate buffer (25 mM, pH 5.5) and an applied voltage of -25 kV, the addition of silver nitrate or beta-cyclodextrin significantly improved the resolution of some more highly charged carboxylic acids.