Radiosensitizing Effects of CDK4/6 Inhibitors in Hormone Receptor-Positive and HER2-Negative Breast Cancer are through Downregulating DNA Repair Mechanism and NF-κB-Signaling Pathway

PURPOSE/OBJECTIVE(S)

CDK4/6 inhibitors combined with endocrine therapy are demonstrated to prolong survival for hormone receptor (HR)-positive and HER2-negative advanced breast cancer. We sought to assess whether cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitors can enhance the radiosensitivity and their underlying mechanisms in this subtype of breast cancer through both in vitro and in vivo approaches.

MATERIALS/METHODS

We used MCF-7 and T-47D (HR-positive and HER2-negative) breast cancer cell lines, and different doses of CDK4/6 inhibitors (ribociclib and palbociclib) and radiotherapy (RT) to assess the biological functions and mechanisms through in vitro study. The radiation enhancing effect was assessed by clonogenic assay, numbers of the DNA damage response-related molecules, γH2AX and 53BP1, were assessed by immunofluorescence. The p-ERK, c-Myc, and DNA-double strand break (DNA-DSB)-related molecules, p-DNA-PKcs, and p-ATM, were assessed by western blotting. We used NF-κB p65 Transcription Factor Assay Kit to evaluate the transcriptional activity of NF-κB. We evaluated the antitumor effect of combined RT (2 Gy every other day for total 6 Gy) and ribociclib through the MCF-7 orthotopic xenograft model.

RESULTS

The synergistic effects of combining RT with different concentrations of ribociclib and palbociclib pretreatment were demonstrated by colonogenic assay. We revealed that CDK4/6 inhibitors synergistically increased the numbers of RT-induced γH2AX and 53BP1, downregulated the expression of p-DNA-PKcs and p-ATM activated by RT, and diminished the expression of RT-triggering p-ERK expression, and NF-κB activation and its down-streaming gene, c-Myc. When compared with control, ribociclib, and RT group, combined ribociclib and RT significantly shrunk the tumor growth of MCF-7 cell xenograft tumors, and downregulated the immunohistochemical expression of p-ERK, p-NF-κB p65, and c-Myc than control group.

CONCLUSION

Our results demonstrated that combining CDK4/6 inhibitors enhanced the radiosensitivity in HR-positive and HER2-negative breast cancer cells, and conceivably radioenhancing mechanisms of CDK4/6 inhibitors are at least through lessening DNA-DSB repairing processes and weakening the activation of ERK signaling and NF-κB signaling by RT.

Using Digital Technology to Design a Simple Interactive System for Nostalgic Gaming to Promote the Health of Slightly Disabled Elderly People

An interactive digital gaming system with simple tangible interfaces is proposed for use by slightly disabled elderly people to promote their health and enjoyment of playful aging. The system simulates a rice threshing machine with nostalgic and entertaining functions expected to bring better life quality to older adults. Initially, pieces of literature were reviewed to derive relevant design principles. A prototype system was constructed accordingly and refined according to the invited older users' comments. The refined system was performed subsequently by slightly disabled elderly people, followed by a questionnaire survey conducted to collect their opinions. The opinion data were analyzed statistically by SPSS and AMOS to be reliable and valid. In addition, interviews were conducted with the users and experts were invited to collect comments on the system's usability, which were then evaluated to reveal several findings about the system's effectiveness: (1) digital products related to life experiences are more acceptable to slightly disabled elderly people, promoting their willingness to play games to achieve active aging; (2) simple system interfaces requiring no complicated limb functions are appropriate for the slightly disabled elderly people; and (3) digital gaming has the effects of training slightly disabled elderly peoples' cognitive and motor abilities as well as strengthening their body and mind.

[Clinical features and prognostic factors of severe hemophagocytic syndrome in children]

Objective: To explore the clinical characteristics, prognostic risk factors and effective treatment of severe hemophagocytic syndrome (HPS) in children, so as to provide reference for the clinical diagnosis and treatment of the disease. Methods: The clinical data of 83 children with severe HPS admitted in Affiliated Hospital of Zunyi Medical University from January 2014 to April 2021 were collected, and their clinical characteristics, prognosis and prognostic risk factors were analyzed. The children were divided into central nervous system (CNS) dysfunction group and non-CNS dysfunction group according to whether they were accompanied with CNS dysfunction, and were divided into blood purification group and non-blood purification group according to whether they received blood purification, then the survival differences were compared. Results: Among the 83 children, there were 43 males and 40 females, aged[M(Q₁,Q₃)] 36(15,27)months. A total of 51 children were induced by infection, among which 41 children (80.4%) were infected with EB virus. All the children were accompanied by multiple organ dysfunction (MODS), and dysfunction of the blood system (72.3%), liver (71.1%), respiratory system (53.0%) and CNS (37.3%) were common. By the end of follow-up, 40 cases (48.2%) survived, 38 cases (45.8%) died, and 5 cases (6.0%) were lost to follow-up. CNS dysfunction was a risk factor (HR=3.358, 95%CI: 1.445-7.803, P=0.005) and blood purification was a protective factor (HR=0.362, 95%CI: 0.179-0.730, P=0.005) affecting the prognosis of children. The mortality of CNS dysfunction group was statistically higher than that of non-CNS dysfunction group (74.2% vs 28.8%) (P<0.001); The mortality of blood purification group was statistically lower than that of non-blood purification group (31.0% vs 61.0%) (P=0.010). Conclusions: Severe HPS in children was dangerous and had a poor overall prognosis. CNS dysfunction was a risk factor for death. Blood purification could significantly improve the prognosis and improve the survival rate of children.

Pathologic complete response (pCR) to neoadjuvant treatment with or without atezolizumab in triple negative, early high-risk and locally advanced breast cancer. NeoTRIP Michelangelo randomized study

BACKGROUND

High-risk triple negative breast cancers (TNBC) are characterized by poor prognosis, rapid progression to metastatic stage and onset of resistance to chemotherapy, thus representing an area in need of new therapeutic approaches. PD-L1 expression is an adaptive mechanism of tumour resistance to tumour infiltrating lymphocytes, which in turn are needed for response to chemotherapy. Overall, available data support the concept that blockade of PD-L1/PD-1 check-point may improve efficacy of classical chemotherapy.

PATIENTS AND METHODS

Two-hundred-eighty patients with TNBC were enrolled in this multicentre study (NCT002620280) and randomized to neoadjuvant carboplatin AUC 2 and nab-paclitaxel 125 mg/m² iv on days 1 and 8, without (N = 142) or with (N = 138) atezolizumab 1200 mg iv on day 1. Both regimens were given q3 weeks for 8 cycles before surgery and 4 cycles of an adjuvant anthracycline regimen. The primary aim of the study is to compare event-free survival, an important secondary aim was the rate of pathological complete remission (pCR defined as absence of invasive cells in breast and lymph nodes). The primary population for all efficacy endpoints is the intention-to-treat population.

RESULTS

The intention-to-treat analysis revealed that pCR rate after treatment with atezolizumab (48.6%) did not reach statistical significance compared to no atezolizumab [44.4%: odds ratio (OR) 1.18; 95% CI 0.74-1.89; P = 0.48]. Treatment-related adverse events were similar with either regimen except for a significantly higher overall incidence of serious adverse events and liver transaminases abnormalities with atezolizumab.

CONCLUSIONS

The addition of atezolizumab to nab-paclitaxel and carboplatin did not significantly increase the rate of pCR in women with TNBC. In multivariate analysis the presence of PD-L1 expression was the most significant factor influencing rate of pCR (OR 2.08). Continuing follow up for the event-free survival is ongoing, and molecular studies are under way.

Adjuvant abemaciclib combined with endocrine therapy for high-risk early breast cancer: updated efficacy and Ki-67 analysis from the monarchE study

BACKGROUND

Adjuvant abemaciclib combined with endocrine therapy (ET) previously demonstrated clinically meaningful improvement in invasive disease-free survival (IDFS) and distant relapse-free survival (DRFS) in hormone receptor-positive, human epidermal growth factor receptor 2-negative, node-positive, high-risk early breast cancer at the second interim analysis, however follow-up was limited. Here, we present results of the prespecified primary outcome analysis and an additional follow-up analysis.

PATIENTS AND METHODS

This global, phase III, open-label trial randomized (1 : 1) 5637 patients to adjuvant ET for ≥5 years ± abemaciclib for 2 years. Cohort 1 enrolled patients with ≥4 positive axillary lymph nodes (ALNs), or 1-3 positive ALNs and either grade 3 disease or tumor ≥5 cm. Cohort 2 enrolled patients with 1-3 positive ALNs and centrally determined high Ki-67 index (≥20%). The primary endpoint was IDFS in the intent-to-treat population (cohorts 1 and 2). Secondary endpoints were IDFS in patients with high Ki-67, DRFS, overall survival, and safety.

RESULTS

At the primary outcome analysis, with 19 months median follow-up time, abemaciclib + ET resulted in a 29% reduction in the risk of developing an IDFS event [hazard ratio (HR) = 0.71, 95% confidence interval (CI) 0.58-0.87; nominal P = 0.0009]. At the additional follow-up analysis, with 27 months median follow-up and 90% of patients off treatment, IDFS (HR = 0.70, 95% CI 0.59-0.82; nominal P < 0.0001) and DRFS (HR = 0.69, 95% CI 0.57-0.83; nominal P < 0.0001) benefit was maintained. The absolute improvements in 3-year IDFS and DRFS rates were 5.4% and 4.2%, respectively. Whereas Ki-67 index was prognostic, abemaciclib benefit was consistent regardless of Ki-67 index. Safety data were consistent with the known abemaciclib risk profile.

CONCLUSION

Abemaciclib + ET significantly improved IDFS in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative, node-positive, high-risk early breast cancer, with an acceptable safety profile. Ki-67 index was prognostic, but abemaciclib benefit was observed regardless of Ki-67 index. Overall, the robust treatment benefit of abemaciclib extended beyond the 2-year treatment period.

[A multicenter prospective randomized controlled clinical study of 5-fluorouracil in different mass concentrations combined with triamcinolone in the treatment of keloids]

Objective: To evaluate the clinical effects of 5-fluorouracil in different mass concentrations combined with triamcinolone in the treatment of keloids. Methods: From March 2018 to March 2019, 29 patients with 31 keloids receipted in the Department of Plastic Surgery of Fujian Medical University Union Hospital, 11 patients with 20 keloids receipted in the Department of Dermatology of Pingtan Comprehensive Experimental Area Hospital, and 9 patients with 9 keloids receipted in the Fuzhou Heisey-Dea Aesthetic Clinic were included in this prospectively randomized control study, with 27 males and 22 females, aged (30±9) years. According to the random number table, the keloids were divided into low mass concentration group (19 keloids, 17 patients), medium mass concentration group (21 keloids, 19 patients), and high mass concentration group (20 keloids, 17 patients). Then 5-fluorouracil at mass concentrations of 0.5, 5.0, and 12.5 mg/mL combined with triamcinolone acetonide were injected respectively, once every 4 weeks, for a total of 3 times. Before the first treatment and in 3 months after the last treatment, the appearance of keloids was evaluated by Vancouver Scar Scale (VSS) and pain and pruritus of keloids were evaluated by Visual Analogue Scale (VAS). Then the score differences before and after the treatment were calculated. In 6 months after the last treatment, the patients' efficacy satisfaction was evaluated by efficacy satisfaction rating scale. Adverse reactions during the treatment were recorded. In the follow-up of one year after the last treatment, the recurrence rates of keloids were counted. Data were statistically analyzed with chi-square test, one-way analysis of variance, paired sample t test, least significant difference t test, Wilcoxon rank sum test, Kruskal-Wallis rank sum test, or Fisher's exact probability test. Results: Before the first treatment, the appearance VSS scores of appearance of keloids in the three groups were similar (F=0.039, P>0.05). In 3 months after the last treatment, the appearance VSS scores of keloids in low mass concentration group were significantly higher than those in medium mass concentration group and high mass concentration group (t=2.267, 4.086, P<0.05 or P<0.01). In 3 months after the last treatment, the appearance VSS scores of keloids in low mass concentration group, medium mass concentration group, and high mass concentration group were significantly decreased compared with those before the first treatment (t=18.222, 44.272, 22.523, P<0.01). The differences of appearance VSS scores of keloids in low mass concentration group before and after treatment were significantly lower than those in medium mass concentration group and high mass concentration group (t=-4.096, -6.357, P<0.01), and the differences of appearance VSS scores of keloids in medium mass concentration group before and after treatment were significantly lower than those in high mass concentration group (t=-2.368, P<0.05). Before the first treatment, the pain and pruritus VAS scores of keloids in the three groups were similar (χ²=0.149, P>0.05). In 3 months after the last treatment, the pain and pruritus VAS scores of keloids in low mass concentration group were significantly higher than those in medium mass concentration group and high mass concentration group (Z=2.191, 4.386, P<0.05 or P<0.01), and the pain and pruritus VAS scores of keloids in medium mass concentration group were significantly higher than those in high mass concentration group (Z=2.276, P<0.05). In 3 months after the last treatment, the pain and pruritus VAS scores of keloids in medium mass concentration group and high mass concentration group were significantly decreased compared with those before the first treatment (Z=-3.904, -3.844, P<0.01). The differences of pain and pruritus VAS scores of keloids in low mass concentration group before and after treatment were significantly lower than those in medium mass concentration group and high mass concentration group (Z=-4.265, -6.104, P<0.01). In 6 months after the last treatment, the efficacy satisfaction scores of the corresponding patients of keloids were (88±8) points in high mass concentration group, which were significantly higher than (76±8) points in medium mass concentration group and (60±8) points in low mass concentration group (t=-3.820, -6.675, P<0.01), and the efficacy satisfaction scores of the corresponding patients of keloids in medium mass concentration group were significantly higher than those in high mass concentration group (t=-2.984, P<0.05). There was only statistically significant difference in pain within the 3 groups (P<0.01). In the follow-up of one year after the last treatment, the recurrence rate of keloids in high mass concentration group was significantly lower than that in low mass concentration group (χ²=8.313, P<0.01), and the recurrence rate of keloids in medium mass concentration group was similar to the recurrence rates in low mass concentration group and high mass concentration group (P>0.05). Conclusions: After treating keloids with high mass concentration of 5-fluorouracil combined with triamcinolone acetonide, the symptoms were significantly improved, the efficacy satisfaction of patients was increased, with no obvious adverse reactions but long lasting efficacy. Their overall effects are better than treatment using medium and low mass concentrations of 5-fluorouracil, which is worthy of clinical promotion.

Penetration of inferior alveolar nerve canal increased by bicortical fixation after bilateral sagittal split osteotomy in mandibular prognathism

The purpose of this three-dimensional cone beam computed tomography (CBCT) study was to identify the difference between monocortical fixation (MCF) and bicortical fixation (BCF) in mandibular canal penetration after bilateral sagittal split osteotomy (BSSO) to correct mandibular prognathism, where interosseous fixation was done by BCF or MCF. CBCT was performed 1 week postoperatively and Dolphin 3D software was used to assess direct penetration of the mandibular canal by either type of screw. The primary outcome variable was the presence or absence of mandibular canal penetration and was categorized as a binary coded variable. The BCF and MCF groups were compared by χ² test, and the odds ratio for canal penetration was estimated. Multiple logistic regression was performed to identify factors related to canal penetration. A total of 118 patients were included. The MCF group had only 6% canal penetrations (3/50 patients) and the BCF group had 58.8% canal penetrations (40/68 patients). The regression model showed that BCF was the only factor causing mandibular canal penetration, with an adjusted odds ratio of 52.5. Awareness of the increased risk of canal penetration with BCF and potential nerve injury might influence case selection.

The impact of a surgery-first approach on oral health-related quality of life

Orthognathic surgery using a surgery-first approach (SFA) has been shown to result in better quality of life (QoL) throughout the treatment duration; however, the effects of gender, age and type of dentofacial deformity on SFA-related QoL remain unknown. In total, 228 consecutive patients underwent SFA for correction of dentofacial deformities (skeletal class III, bimaxillary protrusion and facial asymmetry). We assessed their QoL before surgery and at 1, 6 and 12 months after surgery using the Orthognathic Quality of Life Questionnaire (OQLQ). The results indicated a significant decrease in the total OQLQ, facial aesthetics and social aspect domain scores 1, 6 and 12 months after surgery. Among all domains, the greatest improvement was noted in the facial aesthetics domain. The oral function scores declined significantly immediately after surgery, but improved significantly 6 and 12 months after surgery; however, the awareness scores remained relatively stable. At each time point, women and the bimaxillary protrusion group exhibited a significantly higher total and specific domain scores. Patients aged 18-22 years exhibited lower total and four specific domain scores than older patients. Thus, QoL improves in all aspects, except awareness domain, by 12 months after SFA, but gender, age, and type of dentofacial deformity affect this improvement.

Design of an Interactive Nostalgic Amusement Device with User-Friendly Tangible Interfaces for Improving the Health of Older Adults

To help older adults achieve active aging, an interactive device with tangible interfaces is proposed, which combines human-machine interaction techniques and older adults' life experiences to provide three functions: nostalgia, leisure, and entertainment. Firstly, by a review of related theories and studies, principles for designing a desirable interactive device were established. Accordingly, a prototype device with an interactive game was constructed, which was then tested in a field experiment and improved according to the users' opinions collected by interviews. Subsequently, in a second experiment the users' and some experts' feedback about the system's usability and user interaction satisfaction was collected and analyzed, and found to be reliable and valid for further evaluations of the effectiveness of the proposed system, resulting in the following findings about the older adults who have played the game: the participants become more willing to use technological devices; involving them in the game creates positive aging effects; participants become more receptive to technology products; the participating older adults' cognitive abilities are trained and their body exercises increased, creating sensory stimulation and health promotion effects; and considering users with cognitive impairments who have stress and difficulty operating the device, the system needs to be improved in the future.

Toxicity profile differences of adjuvant docetaxel/cyclophosphamide (TC) between Asian and Caucasian breast cancer patients

AIM

For early-stage breast cancer, four cycles of docetaxel and cyclophosphamide (TC) was proven superior to doxorubicin plus cyclophosphamide in the US Oncology 9375 trial. Given primary prophylactic antibiotics, 5% febrile neutropenia was recorded in a population comprising 75.5% Caucasians. Smaller trials and retrospective studies reviewing TC use in Asian patients did not produce similar incidence rates. This study aims to discover the variable hematological toxicities with TC use in Caucasian and Asian patients.

METHODS

Breast cancer data was retrospectively reviewed for patients receiving adjuvant docetaxel 60-75 mg/m² plus cyclophosphamide 600 mg/m² from six countries (China, Hong Kong, Japan, Taiwan, Italy, and United States). Similar number of patients with relatively balanced baseline characteristics were chosen for analysis of hematological and nonhematological toxicities and survival data.

RESULTS

From March 2004 to July 2013, data of 227 patients (127 Asians and 100 Caucasian) patients were analyzed for treatment-related toxicities. During the four cycles of TC, Asians had a significantly higher rate of grade ≥2 neutropenia than Caucasians (45.7% vs 6.0%; P <0.001) and significantly more grade ≥3 neutropenia events were documented (respectively 30.7% vs 4.0%, P <0.001). The prophylactic use of G-CSF was similar; 26.0% in Asians and 28.0% in Caucasian (P = 0.764). There were no differences in nonhematological toxicities. No significant difference in disease-free survival was observed between Asians and Caucasians (log-rank P = 0.910).

CONCLUSIONS

Ethnic differences in toxicity profile exist between Asian and Caucasian patients given adjuvant TC. Over 30% Asians but less than 5% Caucasians experienced grade ≥3 neutropenia.

Nephrolithiasis among male patients with newly diagnosed gout

INTRODUCTION

An elevated serum urate level is recognised as a cause of gouty arthritis and uric acid stone. The level of serum uric acid that accelerates kidney stone formation, however, has not yet been clarified. This study aimed to find out if a high serum urate level is associated with nephrolithiasis.

METHODS

Patients were recruited from the rheumatology clinic of Taipei City Hospital (Renai and Zhongxing branches) in Taiwan from March 2015 to February 2016. A total of 120 Chinese male patients with newly diagnosed gout and serum urate concentration of >7 mg/dL and no history of kidney stones were divided into two groups according to their serum urate level: <10 mg/dL (group 1, n=80) and ≥10 mg/dL (group 2, n=40). The mean body mass index, blood urea nitrogen level, creatinine level, urinary pH, and kidney ultrasonography were compared between the two groups.

RESULTS

There were no significant differences in blood urea nitrogen or creatinine level between the two groups. The urine pH in both groups was similar and not statistically significant. Kidney stone formation was detected via ultrasonography in 6.3% (5/80) and 82.5% (33/40) of patients in groups 1 and 2, respectively (P<0.05).

CONCLUSION

A serum urate level of ≥10 mg/dL may precipitate nephrolithiasis. Further studies are warranted to substantiate the relationship between serum urate level and kidney stone formation.

Swimming exercise ameliorates neurocognitive impairment induced by neonatal exposure to isoflurane and enhances hippocampal histone acetylation in mice

Isoflurane-induced neurocognitive impairment in the developing rodent brain is well documented, and regular physical exercise has been demonstrated to be a viable intervention for some types of neurocognitive impairment. This study was designed to investigate the potential protective effect of swimming exercise on both neurocognitive impairment caused by repeated neonatal exposure to isoflurane and the underlying molecular mechanism. Mice received 0.75% isoflurane exposures for 4h on postnatal days 7, 8, and 9. From the third month after anesthesia, the mice were subjected to regular swimming exercise for 4weeks, followed by a contextual fear condition (CFC) trial. We found that repeated neonatal exposure to isoflurane reduced freezing behavior during CFC testing and deregulated hippocampal histone H4K12 acetylation. Conversely, mice subjected to regular swimming exercise showed enhanced hippocampal H3K9, H4K5, and H4K12 acetylation levels, increased numbers of c-Fos-positive cells 1h after CFC training, and less isoflurane-induced memory impairment. We also observed increases in histone acetylation and of cAMP-response element-binding protein (CREB)-binding protein (CBP) during the swimming exercise program. The results suggest that neonatal isoflurane exposure-induced memory impairment was associated with dysregulation of H4K12 acetylation, which may lead to less hippocampal activation following learning tasks. Swimming exercise was associated with enhanced hippocampal histone acetylation and CBP expression. Exercise most likely ameliorated isoflurane-induced memory impairment by enhancing hippocampal histone acetylation and activating more neuron cells during memory formation.

Evaluation of a pilot volunteer feeding assistance program: influences on the dietary intakes of elderly hospitalised patients and lessons learnt

OBJECTIVES

Malnutrition is a serious concern in hospitals and is known to be associated with increased complications for patients, increased hospital costs and length of stay. Trained volunteers that assist 'at risk' and malnourished patients at lunch meals have been shown to effectively increase nutritional intake in a suburban hospital in Sydney. The pilot study reported here aimed to evaluate and share learnings from a similar, newly implemented program, comparing energy and macronutrient intakes on days with no volunteer assistance, to days with volunteers.

DESIGN

Dietary intakes were determined by visual estimation of meal trays before and after meals, for two days without volunteers, and two days with volunteer assistance at lunch. Macronutrient and energy intakes were compared and data such as weight, height, diet type and medical history were obtained from medical records. Questionnaires were completed by nurses and volunteers in regards to their views and experiences with the program.

SETTING

Hospital based.

RESULTS

Eight patients (83±4.5 years) participated in the study. When volunteers were present at lunch, the average macronutrient and energy intakes increased, though not statistically significantly. The mean increases were 316 kJ (p=0.175) for energy, 3.1 g (p=0.468) for protein, 1.4 g (p=0.418) for fat and 11.6 g (p=0.084) for carbohydrates. Non-significant increases in macronutrients were also noted for the average daily intakes.

CONCLUSION

Although not statistically significant, energy and macronutrient intakes increased when volunteers were present. The implementation of a volunteer feeding assistance program is one strategy to assist dietary intakes but requires a ready team of volunteers, training, acceptance and significant time to develop.

Lack of efficacy to systemic chemotherapy for treatment of metaplastic carcinoma of the breast in the modern era

Metaplastic carcinoma of the breast (MCB) is a rare subtype of breast cancer. Anecdotal reports are available regarding its response to systemic chemotherapy. We reviewed the records of patients diagnosed with MCB at National Taiwan University Hospital between 1988 and 2009. A total of 46 MCB cases were identified from 8,695 breast tumor patients who underwent biopsy or resection. About 11 of 25 patients with initial bulky disease (T3-4) received neoadjuvant chemotherapy before surgery, and 2 (18.2%) exhibited a partial response. About 12 of 18 patients who developed distant metastasis received palliative systemic chemotherapy. Of them, only 1 (8.3%), 1 (10%), and none (0%) responded to first-, second-, or third- and beyond line chemotherapy, respectively. None of the patients who received anthracyline- (n = 13), vinorelbine- (n = 7), or cyclophosphamide-based (n = 18) chemotherapy responded, whereas 3 (17.6%) of 17 patients who received taxane-based chemotherapy exhibited a partial response. Tumor response to systemic chemotherapy remains generally poor for MCB patients. Taxanes may have modest activity, but need to be validated in further studies.

Surgery-first accelerated orthognathic surgery: postoperative rapid orthodontic tooth movement

PURPOSE

Clinically, we have observed the phenomenon of postoperatively accelerated orthodontic tooth movement in patients who had orthognathic surgery. This phenomenon lasts for a period of 3 to 4 months. However, the underlying mechanisms of this phenomenon have not been well studied yet. The purpose of this prospective clinical pilot study was to study the postoperative changes in bone physiology and metabolism and the corresponding responses in the dentoalveolus, such as the changes in tooth mobility.

MATERIALS AND METHODS

Twenty-two consecutive adult patients who had 2-jaw orthognathic surgery were included in this study. The levels of serum alkaline phosphatase and C-terminal telopeptide of type I collagen (ICTP), as well as the tooth mobility of the maxillary and mandibular incisors based on the Periotest method (Siemens AG, Bensheim, Germany), were examined preoperatively and 1 week, 1 month, 2 months, 3 months, and 4 months postoperatively. The data were analyzed statistically.

RESULTS

Both tooth mobility of the maxillary and mandibular incisors and ICTP significantly increased from 1 week to 3 months postoperatively and then decreased to their preoperative levels in the fourth month postoperatively. The changes in tooth mobility were significantly in correspondence with the changes in ICTP. The alkaline phosphatase level significantly increased from the first to fourth month postoperatively, but it was not significantly correlated to the changes in tooth mobility.

CONCLUSION

The orthognathic surgery triggers a 3- to 4-month period of higher osteoclastic activities and metabolic changes in the dentoalveolus postoperatively, which possibly accelerates postoperative orthodontic tooth movement.

Multicolor fluorescence enhancement from a photonics crystal surface

A photonic crystal substrate exhibiting resonant enhancement of multiple fluorophores has been demonstrated. The device, fabricated uniformly from plastic materials over a ∼3×5 in.(2) surface area by nanoreplica molding, utilizes two distinct resonant modes to enhance electric field stimulation of a dye excited by a λ=632.8 nm laser (cyanine-5) and a dye excited by a λ=532 nm laser (cyanine-3). Resonant coupling of the laser excitation to the photonic crystal surface is obtained for each wavelength at a distinct incident angle. Compared to detection of a dye-labeled protein on an ordinary glass surface, the photonic crystal surface exhibited a 32× increase in fluorescent signal intensity for cyanine-5 conjugated streptavidin labeling, while a 25× increase was obtained for cyanine-3 conjugated streptavidin labeling. The photonic crystal is capable of amplifying the output of any fluorescent dye with an excitation wavelength in the 532 nm<λ<633 nm range by selection of an appropriate incident angle. The device is designed for biological assays that utilize multiple fluorescent dyes within a single imaged area, such as gene expression microarrays.

Dynamic seizure-related changes in extracellular signal-regulated kinase activation in a mouse model of temporal lobe epilepsy

Extracellular signal-regulated kinase (ERK) is highly sensitive to regulation by neuronal activity and is critically involved in several forms of synaptic plasticity. These features suggested that alterations in ERK signaling might occur in epilepsy. Previous studies have described increased ERK phosphorylation immediately after the induction of severe seizures, but patterns of ERK activation in epileptic animals during the chronic period have not been determined. Thus, the localization and abundance of phosphorylated extracellular signal-regulated kinase (pERK) were examined in a pilocarpine model of recurrent seizures in C57BL/6 mice during the seizure-free period and at short intervals after spontaneous seizures. Immunolabeling of pERK in control animals revealed an abundance of distinctly-labeled neurons within the hippocampal formation. However, in pilocarpine-treated mice during the seizure-free period, the numbers of pERK-labeled neurons were substantially decreased throughout much of the hippocampal formation. Double labeling with a general neuronal marker suggested that the decrease in pERK-labeled neurons was not due primarily to cell loss. The decreased ERK phosphorylation in seizure-prone animals was interpreted as a compensatory response to increased neuronal excitability within the network. Nevertheless, striking increases in pERK labeling occurred at the time of spontaneous seizures and were evident in large populations of neurons at very short intervals (as early as 2 min) after detection of a behavioral seizure. These findings suggest that increased pERK labeling could be one of the earliest immunohistochemical indicators of neurons that are activated at the time of a spontaneous seizure.

Antioxidant and pro-oxidant properties of chlorhexidine and its interaction with calcium hydroxide solutions

AIM

To evaluate the antioxidant and pro-oxidant properties of chlorhexidine (CHX).

METHODOLOGY

The scavenging and generation of reactive oxygen species (ROS) by CHX in the presence or absence of saturated Ca(OH)(2) solutions was evaluated. The reaction emitted chemiluminescence in the presence of lucigenin thus was determined by a luminometer to evaluate the levels of ROS production. Changes in DNA conformation were analysed by agarose gel electrophoresis. Paired Student's t-test was used to compare the difference between groups.

RESULTS

Chlorhexidine (0.00002-0.02%) effectively scavenged 56-88% of the superoxide radicals generated by the xanthine/xanthine oxidase reaction. Through analysis of PUC18 DNA conformation changes, CHX was shown to be a mild scavenger of hydroxyl radicals generated by H(2)O(2) plus FeCl(2). However, CHX (>0.083%) decreased the mobility of PUC18 plasmid DNA with potential production of DNA-DNA cross-link and severe DNA breaks (presence of DNA smear) at further higher concentrations. Furthermore, CHX induced ROS production including H(2)O(2) and superoxide radicals in 0.1N NaOH (pH = 12.76) or Ca(OH)(2) (pH = 12.5) solutions.

CONCLUSION

Chlorhexidine exhibited both antioxidant and pro-oxidant properties under different conditions. These events are possibly involved in the killing of root canal and periodontal microorganisms when CHX and Ca(OH)(2) were used in combination or separately. Potential genotoxicity and tissue damage when extruded into the periradicular tissue and at higher concentrations should be considered during periodontal and endodontic practice.

B-group vitamins, MTHFR C677T polymorphism and carotid intima-media thickness in clinically healthy subjects

OBJECTIVE

Plasma B-group vitamins and age may affect the carotid intima-media thickness (IMT) in subjects with different 677TT genotype of the methylenetetrahydrofolate reductase (MTHFR) gene.

DESIGN

A hospital-based cross-study.

SETTING

Genomic and Vascular Center, Changhua Christian Hospital, Changhua, Taiwan.

SUBJECTS

Five hundred and forty-one clinically healthy subjects.

INTERVENTION

Fasting plasma, homocysteine (Hcy), vitamin B(6), vitamin B(12), folate and B-mode carotid ultrasound.

RESULTS

MTHFR genotype, plasma concentrations of folate, vitamin B(6) and vitamin B(12) and age were significantly correlated to the plasma Hcy concentration. MTHFR 677TT carriers had higher concentrations of Hcy than did subjects with the CC and CT genotypes. Age, sex, body mass index and plasma Hcy were independent contributors to increase carotid IMT. However, with stratification by mean value of age and B-group vitamins concentrations, we found that at advanced age, lower plasma folate and vitamin B(12) were three risk factors involved in the enhancing effect of the MTHFR 677TT genotype on the increase of plasma Hcy and carotid IMT.

CONCLUSION

MTHFR 677TT-related carotid atherosclerosis was only identified in healthy elderly subjects with lower level of plasma folate and vitamin B(12).

SPONSORSHIP

Changhua Christian Hospital.

Non-traumatic colon perforation in children: a 10-year review

Colon perforation is an abdominal surgical emergency in the pediatric population, but is seldom reported when occurring from non-traumatic causes in children beyond the neonate. The goal of this study was to identify the clinical characteristics, management, and outcomes of non-traumatic colon perforation in children. Medical records for the 10-year period from September 1994 to September 2004 were reviewed for children beyond the neonate with non-traumatic colon perforation. Data gathered included age, gender, symptoms, duration of symptoms, physical findings, and length of postoperative hospital stay. Diagnostic information included laboratory data, radiographic imaging, and operative findings. Forty-four patients with non-traumatic colon perforation were recruited into this study. The mean age was 2.22 +/- 1.87 years; 91.4% of cases were younger than 5 years old. The most common presenting symptom was fever (97.7%); the most common sign was abdominal distention (93.1%). The mean duration of symptoms prior to admission was 6.19 days. Pneumoperitoneum was presented in 86.3% of patients by plain abdominal radiograph. Ascending and transverse colon were the most common perforation sites. Non-typhoid salmonella was the leading pathogen isolated, causing 20.4% of episodes. One case died due to Clostridium speticum infection. Non-traumatic colon perforation most commonly affects children younger than 5 years of age. It may be secondary to infection, especially non-typhoid salmonella. Plain abdominal radiograph can be an adjuvant tool for the high index of suspicion for colon perforation in children with abdominal distention and history of fever or diarrhea for more than 5 days.

Prolene hernia system compared with mesh plug technique: a prospective study of short- to mid-term outcomes in primary groin hernia repair

Two types of anterior tension-free hernioplasty, prolene hernia system (PHS) repair and mesh plug technique (MPT), were introduced to Taiwan in 2001. This study compared the short- to mid-term outcomes following primary groin hernia repair with PHS and MPT. From January 2001 to December 2003, 393 patients with 426 primary groin hernias were operated on by a single surgeon using MPT (n=192) and PHS (n=234). Baseline perioperative details and follow-up information were compared. Demographic characteristics of both groups were similar. The laterality, types of anesthesia, postoperative stay, postoperative wound pain scores, wound complications and days to return to activities of daily life were equally distributed between the two groups. However, the distribution of Gilbert types in the PHS group was shifted a little to the right compared with that of the MPT group. PHS repair had longer operative time (34+/-17 vs 25+/-9 minutes, p<0.01). No recurrence was noted in both groups during the follow-up from 5 to 41 months. Chronic non-disabling groin pains were noted in 2.8% (6/218) of patients in the PHS group and 8.9% (14/175) in the MPT group (p=0.01). Our results show that both PHS and MPT repairs can be performed with short operation time, minor wound pain and quick return to activities of daily life without short- to mid-term recurrences, but postoperatively the MPT group had higher incidence of chronic non-disabling groin pain. Although the MPT is less invasive, the additional protective patch in the preperitoneal space of the PHS may provide a further safeguard against recurrences, especially for those patients with attenuated inguinal floor. Long-term follow-up is needed.

Long-term results of major bile duct injury associated with laparoscopic cholecystectomy

BACKGROUND

Major bile duct injury (MBDI) is the most serious complication associated with laparoscopic cholecystectomy (LC). This study reports on long-term outcomes and clinical factors which predicted the outcome of 25 patients with LC-associated MBDI.

METHODS

Twenty-five consecutive patients receiving either primary (n = 11) or redo (n = 14) biliary reconstructive surgery at Cathay General Hospital for LC-associated MBDI were prospectively followed for 2 to 10 (mean, 4.5) years to assess their long-term outcomes. Twelve clinical factors relevant to their outcomes were analyzed.

RESULTS

There was no mortality. Although the 1-year postoperative results were successful in 23 patients (92%), the mid- to long-term outcomes were successful in only 17 patients (68%). Eight patients (32%) developed biliary strictures at an average of 3.3 years postoperatively and required subsequent reoperation or biliary stenting. Statistical comparison of 12 risk factors between the successful and unsuccessful groups revealed that two were significant, namely, repair performed by a nonreferral surgeon (p = 0.02) and repair at a stage with recent active inflammation (p = 0.04). A serum alkaline phosphatase level greater than 400 IU in the sixth postoperative month was highly correlated with long-term nonsuccess (p = 0.01).

CONCLUSIONS

Only 68% of patients with LC-associated MBDI who underwent reconstructive surgery at our institution had long-term success. A serum alkaline phosphatase level above 400 IU in the sixth postoperative month was predictive of nonsuccess. For better long-term results, repair should be performed by the referral surgeon at a stage without coexisting active inflammation.

Scavenging property of three cresol isomers against H2O2, hypochlorite, superoxide and hydroxyl radicals

Formocresol has long been used for pulpotomy of primary teeth and as an intracanal medicament. Little is known, however, about the pharmacological effect of tricresols. This study showed that three cresol isomers, o-cresol, m-cresol and p-cresol, are H2O2 scavengers with a 50% inhibitory concentration (IC50) of 502, 6.7 and 10.16 microM, respectively. o-, m- and p-cresol were also shown to be effective scavengers of superoxide radicals generated by xanthine/xanthine oxidase with an IC50 of 282, 153 and > 4000 microM, respectively, as analyzed by luminometer. o-, m- and p-cresol showed protective effects on the DNA breaks generated by H2O2/FeCl2 and FeCl3/ascorbate/H2O2 systems at concentrations ranging from 70 microM to 1.43 mM, o-, m- and p-cresol also showed differential protective effects against DNA breaks induced by 0.17% NaOCl with 100% inhibitory concentration (IC100) of about 10, 1 and 10 mM, respectively. In addition, reaction with 3% H2O2 and 0.17% NaOCl completely prevented NaOCl-induced DNA breaks. The results indicate that the three cresol isomers are effective ROS scavengers and may prevent ROS induced damage when used as pulpotomy agents or as intracanal medicaments. Owing to the difference in the position of the functional hydroxyl group in the three cresol isomers, m-cresol is the most effective ROS scavenger. Concomitant use of H2O2 for root canal irrigation may diminish both the tissue dissolving capacity of NaOCl and NaOCl-induced DNA damage.

Cooperative binding of gamma-glutamyl substrate to human glutathione synthetase

Human glutathione synthetase is responsible for catalyzing the final step in glutathione biosynthesis. It is a homodimer with a monomer subunit MW of 52 kDa. Kinetic analysis reveals a departure from linearity of the Lineweaver-Burk double reciprocal plot for the binding of gamma-glutamyl substrate, indicating cooperative binding. The measured apparent K(m) values for gamma-glutamyl-alpha-aminobutyrate (an analog of gamma-glutamyl-alpha-aminobutyrate) are 63 and 164 microM, respectively. Neither ATP (K(m) of 248 microM) nor glycine (K(m) of 452 microM) exhibits such cooperative binding behavior. Although ATP is proposed to play a key role in the sequential binding of gamma-glutamyl substrate to the enzyme, the cooperative binding of the gamma-glutamyl substrate is not affected by alterations of ATP concentration. Quantitative analysis of the kinetic results for gamma-glutamyl substrate binding gives a Hill coefficient (h) of 0.75, indicating negative cooperativity. Our studies, for the first time, show that human glutathione synthetase is an allosteric enzyme with cooperative binding for gamma-glutamyl substrate.

Congenital diaphragmatic hernia diagnosed by magnetic resonance imagine in late infancy: Report of one case

We report the magnetic resonance imagine (MRI) findings of an 11-month-old baby with delay onset of congenital diaphragmatic hernia (CDH). The capability of visualizing diaphragmatic discontinuity, connecting bowel segments between abdomen and chest are clearly demonstrated. The various techniques of diagnosing diaphragmatic hernia are described and we emphasize the potential usefulness of MRI in CDH.

Role of laparoscopic cholecystectomy in the management of polypoid lesions of the gallbladder

This retrospective clinicohistopathologic study was performed to delineate the role of laparoscopic cholecystectomy in the management of polypoid lesions of the gallbladder. One hundred forty-three consecutive patients who had a preoperative sonographic diagnosis of polypoid lesions of the gallbladder with a diameter less than 1.5 cm and who underwent laparoscopic cholecystectomy at Cathay General Hospital were included in the analysis. Histopathologic study showed that 22 (15.4%) patients had true tumors, including adenoma (16), adenoma with focal adenocarcinoma (2), adenocarcinoma (3), and carcinoid tumor (1). Tumorlike lesions were found in 121 (84.6%) patients and included cholesterol polyp (106), adenomyomatous hyperplasia (10), inflammatory polyp (3), and papillary hyperplasia (2). The mean diameter of malignant polypoid lesions of the gallbladder was 1.35 +/- 0.42 cm, which was significantly larger than that of cholesterol polyps (0.66 +/- 0.40 cm, P = 0.0001) but not significantly larger than that of adenomyomatous hyperplasias (1.12 +/- 0.42 cm) and adenomas (1.08 +/- 0.47 cm). The mean age of patients with malignant polypoid lesions of the gallbladder (61.2 +/- 13.3 years old) was significantly older than that of patients with adenomyomatous hyperplasia (46.6 +/- 13.4 years, P = 0.03), cholesterol polyps (44.5 +/- 10.5 years, P = 0.0003), and adenomas (41.4 +/- 9.4 years, P = 0.0008). Clinical follow-up showed that most (98.6%) patients benefited from the minimal invasiveness of laparoscopic cholecystectomy with satisfactory surgical results. We conclude that laparoscopic cholecystectomy is a reliable, safe, and minimally invasive biopsy procedure and definite management of polypoid lesions of the gallbladder with a diameter less than 1.5 cm.

Congenital varicella syndrome as an unusual cause of congenital malformation: report of one case

Intrauterine infections with varicella-zoster virus following maternal varicella in early pregnancy and resulting in congenital malformations are rare. Herein we report a child with congenital varicella syndrome characterized by low birth weight, cicatricial scarring, hypoplasia of both lower extremities with joint contracture, congenital hip dislocation, corneal opacity, atresia of the sigmoid colon and a rarely associated cloaca anomaly. The varicella IgG remained positive after she was seven months old. Her mother developed chickenpox at the 14th week of gestation. The purpose of this article is to raise pediatricians' index of suspicion for congenital varicella syndrome when an infant is born with multiple congenital malformations with an apparent history of maternal varicella infection.

Mechanisms of inactivation of E-cadherin in breast carcinoma: modification of the two-hit hypothesis of tumor suppressor gene

Loss of heterozygosity (LOH) allows the expression of recessive mutation in tumor suppressor genes (TSG). Therefore, on the basis of Knudson's 'two-hit' hypothesis for TSG inactivation, the detection of a high LOH frequency in a chromosomal region is considered critical for TSG localization. One of these LOH regions in breast cancer is 16q22.1, which has been suggested to reflect the involvement of E-cadherin (E-cad), a cell-cell adhesion molecule. To confirm the tumorigenic role of E-cad, 81 sporadic invasive ductal carcinomas (IDCs) of the breast were tested for the 'two hits' required to inactivate this gene. A high frequency (37.3%) of LOH was detected in 67 informative tumors, but no mutation was found. To examine the possibility that transcriptional mechanisms serve as the second hit in tumors with LOH, specific pathways, including genetic variant and hypermethylation at the promoter region and abnormal expression of positive (WT1) and negative (Snail) transcription factors, were identified. Of these, promoter hypermethylation and increased expression of Snail were found to be common (>35%), and to be strongly associated with reduced/negative E-cad expression (P<0.05). However, unexpectedly, a significantly negative association was found between the existence of LOH and promoter hypermethylation (P<0.05), which contradicts the 'two-hit' model. Instead, since they coexisted in a high frequency of tumors, hypermethylation may work in concert with increased Snail to inactivate E-cad expression. Given that E-cad is involved in diverse mechanisms, loss of which is beneficial for tumors to invade but may also trigger apoptosis, this study suggests that maintaining a reversible mechanism, either by controlling the gene at the transcriptional level or by retaining an intact allele subsequent to LOH, might be important for E-cad in IDC and may also be common in TSGs possessing diverse functions. These findings provide clues to explain why certain TSGs identified by LOH cannot fulfil the two-hit hypothesis.

Surgical implications of pseudomonas aeruginosa necrotizing fasciitis in a child with acute lymphoblastic leukemia

Necrotizing fasciitis caused by Pseudomonas aeruginosa is extremely rare. Only 4 cases were reported in the literature. The authors report the occurrence of P aeruginosa necrotizing fasciitis starting out as a vulval abscess in a girl before induction chemotherapy for acute lymphoblastic leukemia. To our knowledge, this is the second case described in association with leukemia. In this case, the outcome was favorable because of early surgical intervention, confirming the diagnosis. J Pediatr Surg 36:948-950.

Distinguishing two types of gray mullet, Mugil cephalus L. (Mugiliformes: Mugilidae), by using glucose-6-phosphate isomerase (GPI) allozymes with special reference to enzyme activities

The resident and migratory types of gray mullet, Mugil cephalus, on the coast of Taiwan can not be separated morphologically. Allozyme analysis was applied to estimate genetic variation between the two types of gray mullet and to test whether they belong to different populations. After starch gel electrophoresis, different allelic frequency spectra of glucose-6-phosphate isomerase-A (GPI-A) between stocks was observed. The resident stock contained Gpi-A(135) and Gpi-A(100), whereas the migratory type contained Gpi-A(100) only. In addition, GPI activities of locus A showed two distinct profiles between the two alleles. The results broadly revealed that Gpi-A allelic frequency was not regulated by temperature changes even after 6 months of thermal acclimation. This suggests that natural selection may play a role in shaping the allelic frequency change during the migratory journey. These findings suggest that the Gpi-A allelic difference can be used for population discrimination.

Use of pulsed-field gel electrophoresis to investigate an outbreak of Serratia marcescens infection in a neonatal intensive care unit

Serratia marcescens is a well-recognized hospital-acquired pathogen, which has been associated with a number of specific outbreaks, particularly in critically ill neonates. We used pulsed-field gel electrophoresis (PEGE) typing to analyse an outbreak in a neonatal intensive care unit (NICU). We included samples from nine patients, three handwashes and ten environmental isolates from an outbreak (February to August 1999) in addition to four patient isolates from different wards of our hospital during the same time period. The clinical presentations of the outbreak included bacteraemia (four cases), pneumonia (three cases), umbilical wound infection (one case) and conjunctivitis (one case). Nine outbreak isolates exhibited an identical PFGE fingerprint, while the epidemiologically unrelated strains demonstrated distinct patterns. Epidemiological investigation failed to reveal a common source of the outbreak, although the epidemic S. marcescens strain was isolated from hand-washes and doors of incubators. We concluded that cross-transmission via transient contamination of hands was the major route for this outbreak. Strict handwashing practices, the cohorting and isolation of colonized and infected patients, and the regular dis-infection of incubators are crucial steps for preventing the transmission of S. marcescens in an NICU. This PFGE method is highly discriminatory for the thorough epidemiological investigation of an outbreak of S. marcescens.

Nickel-titanium mandibular bonded lingual 3-3 retainer: for permanent retention and solving relapse of mandibular anterior crowding

An innovative technique that involves a nickel-titanium mandibular bonded lingual 3-3 retainer was used to treat relapse of mandibular anterior crowding. The purpose of this study was to demonstrate clinical procedures and to study the effects of a new mandibular bonded lingual 3-3 retainer on the mandibular dental arch. In 18 patients, changes in the irregularity index and in arch dimensions (intercanine width, arch length, and arch depth) were measured against the patients' mandibular dental casts, which were obtained at completion of the previous orthodontic treatment (T(0)). These measurements were taken at the beginning of retreatment (T(1)), and 2 (T(2)), 4 (T(3)), and 6 (T(4)) months after initiation of retreatment. During the period of relapse (T(0)-T(1)), the irregularity index increased from 1.3 to 3.5 mm and the mandibular arch dimensions decreased. Four months after a segment of.018-in nickel-titanium archwire was bonded lingually from canine to canine, the irregularity index decreased from 3.5 to 1.0 mm and the arch dimensions increased and recovered their original posttreatment dimensions. The nickel-titanium archwire was left in place for permanent retention after the period of retreatment. This simple technique effectively solved relapse of mandibular anterior crowding in 4 months. This mandibular bonded lingual 3-3 retainer could be used both actively, to re-treat mandibular anterior crowding without the use of lingual brackets, and passively, for maintenance as a bonded lingual retainer.

Breast cancer screening in Taiwan and China

In contrast to incidence rates prevailing in women in Western countries, Chinese women in Taiwan and China are considered to have the lowest incidence of breast cancer in the world. However, in the past 20 years, breast cancer incidence in Chinese women has seen a dramatic increase of 50-100%, which strongly supports the need for breast cancer prevention and screening programs. It is also important to indicate that breast cancer in Chinese women is characterized by younger age at tumor onset. More than 50% of the total breast cancer diagnosed annually is found in premenopausal patients, creating the need to initiate breast cancer screening programs in this population. Initially, the breast cancer screening program depended on breast self-examination. Since Chinese women have relatively small breasts, it was assumed that breast cancer was easier to detect by self-examination. However, this strategy has failed. The dilemma of breast cancer screening can be summarized by the fact that Chinese have a rapidly increasing incidence of premenopausal breast cancer, while the overall incidence is still low. Therefore, since premenopausal women have denser breasts than postmenopausal women, and Chinese women have smaller breasts and a higher percentage of dense breasts, increased mammography screening frequency may be not the sole solution to increase detection in this age group. In our experience in Taiwan, the addition of breast ultrasound may be helpful. Nearly all the nonpalpable cancers detected by mammography in our women are due to microcalcifications, and ultrasound is more sensitive in detecting nonpalpable cancers; Therefore, we suggest that a screening program, based on ultrasound to detect nonpalpable cancers not associated with microcalcifications, along with mammography within a long period, may provide more effective protection for Taiwanese and Chinese women against breast cancer.

A second deciduous molar impacted in right maxillary sinus: a long-term follow-up

Primary tooth impaction is quite rare during the development of primary dentition. Various factors contribute to the impaction of a deciduous tooth, including malposition and malformation of the tooth bud, dentomaxillofacial disharmony, tumors, and cysts. This case was a 6-year-old female with complete left cleft lip/palate. A maxillary right second deciduous molar impacting at a high level approximate to the maxillary sinus was noted on the initial visit. To prevent surgical trauma to the surrounding tissue and succedaneous teeth, regular follow-up with radiographic examination was taken every 2 years. After a 7-year long-term follow-up, the impacted second primary molar in the right maxillary sinus had almost completely been resorbed with only about 10% of the original structure left. To the present, the resorption of the impacted deciduous molar seemed to have continued with no major pathological changes. Periodic radiographic examination is strongly advised until the total resorption process is completed.

Hirschsprung's disease presenting with diffuse intestinal pneumatosis in a neonate

In the neonate, pneumatosis intestinalis is almost always associated with necrotizing enterocolitis. The manifestation of diffuse intestinal pneumatosis in Hirschsprung's disease has been reported rarely. It may occur as a result of Hirschsprung's disease complicated with enterocolitis. We report a two-day-old female baby born at term with the problems of failure to pass meconium, progressive abdominal distension and bile stained vomiting. There was an early roentgenographic presentation of pneumatosis intestinalis which might have led to a diagnosis of necrotizing enterocolitis. However, the intestinal pneumatosis resolved within 48 hours. After anorectal manometry and contrast enema examination, an ileostomy was performed at the age of 23 days, and multiple biopsies of intestine showed aganglionosis up to the ileum at the level of 85 cm above the ileocecal valve. Unfortunately, the patient developed short bowel syndrome after operation and died suddenly after an accidental choking at the age of three months. This case suggests that Hirschsprung's disease may have an unusual early roentgenographic presentation with diffuse intestinal pneumatosis in the first few days of life. Anorectal manometries and suction biopsies are crucial for further diagnosis.

Utility assessment for different clinical phases of breast cancer in Taiwan

BACKGROUND AND PURPOSE

Utility is an important index of health-related quality of life (HRQoL). The purpose of this study was to assess utility in different clinical phases of breast cancer in patients in Taiwan.

METHODS

Based on a review of HRQoL literature pertaining to breast cancer and medical records of 979 breast cancer patients admitted to National Taiwan University Hospital from 1991 to 1995, a semi-open checklist describing the diagnosis and treatment activities and impacts of different clinical phases of breast cancer was constructed. The checklist was then reviewed and revised in consultation with surgeons, medical oncologists, radiation oncologists, nurses, and breast cancer patients. Thirty-one clinical and public health experts were invited to assess the utility of each phase with the visual analog scale (VAS), standard gamble (SG), and time trade-off (TTO) methods, according to the description of the average patient's life in the checklist. The Delphi technique was used to reach expert consensus.

RESULTS

The VAS utility scores were highest during screening phases (100 or 90), lower in phases of incidental finding of a tumor (75) and diagnosis (70), and lower still in the initial treatment phases, especially during adjuvant chemotherapy (50). The scores improved during the follow-up phases. There was a higher score for breast-conserving surgery (65) than modified radical mastectomy (60) only in the early follow-up phase. The scores for recurrence or metastasis (30) and terminal stage were considerably lower and reached the lowest level (10 in a general ward and 12.5 at home or in a hospice) among all phases. The utility scores assessed by SG and TTO were higher than those assessed by VAS.

CONCLUSIONS

In this study, we established a consensus among clinical and public health experts on the impact of different clinical phases of breast cancer on utility. The results of this study may be useful in cross-cultural comparisons and cost-utility analyses for breast cancer.

Novel kinetics of mammalian glutathione synthetase: characterization of gamma-glutamyl substrate cooperative binding

Glutathione (GSH) synthetase [L-gamma-glutamyl-L-cysteinyl:glycine ligase (ADP-forming), EC 6.3.2.3] catalyzes the final step in GSH biosynthesis. Mammalian glutathione synthetase is a homodimer with each subunit containing an active site. We report the detailed kinetic data for purified recombinant rat glutathione synthetase. It has the highest specific activity (11 micromol/min/mg) reported for any mammalian glutathione synthetase. The apparent K(m) values for ATP and glycine are 37 and 913 microM, respectively. The Lineweaver-Burk double reciprocal plot for gamma-glutamyl substrate binding revealed a departure from linearity indicating cooperative binding. Quantitative analysis of the kinetic results for gamma-glutamyl substrate binding gives a Hill coefficient (h) of 0. 576, which shows the negative cooperativity. Neither ATP, the other substrate involved in forming the enzyme-bound gamma-glutamyl phosphate intermediate, nor glycine, which attacks this intermediate to form GSH, exhibit any cooperativity. The cooperative binding of gamma-glutamyl substrate is not affected by ATP concentration. Thus, mammalian glutathione synthetase is an allosteric enzyme.

Variations of the bilirubin uridine-diphosphoglucuronosyl transferase 1A1 gene in healthy Taiwanese

The activity of uridine-diphosphoglucuronosyl transferase 1 (UGT1) may influence the concentration of serum bilirubin. Because UGT1 is too labile to be measured with classical biochemical methods, we analysed the whole UGT1A1 gene in 290 healthy Taiwanese adults by using the polymerase chain reaction method, and investigated the relationship between UGT1A1 genotypes and serum bilirubin levels. The results showed that slightly more than 50% of the subjects had one or more variant sites in UGT1A1 gene. The most common variant was A(TA)6TAA/A(TA)7TAA (6/7) in the promoter area, followed by heterozygous variation within the coding region, compound heterozygous and homozygous variations. Among the four variant sites within the coding region, 211 G to A was the predominate one, 1091 C to T was a novel variation, and 686 C to A was associated with 6/7. Subjects with 6/7 or heterozygous variation within the coding region or compound heterozygous (plus one homozygous) variation had significantly higher bilirubin levels than those with wild UGT1A1 gene. When the 290 subjects were stratified into six groups according to their serum bilirubin concentrations, the bilirubin levels were correlated well to the frequencies of variant UGT1A1 gene. Our results show that there is a strong association between UGT1A1 gene and bilirubin levels in healthy Taiwanese adults. The occurrence of A(TA)7TAA allele was relatively rare and the variation rate within the coding region was much higher in Taiwanese compared to that in Caucasians.

Prolonged neuromuscular block with mivacurium in a patient with cholinesterase deficiency

Mivacurium is a short-acting, nondepolarizing neuromuscular blocking agent hydrolyzed by plasma cholinesterase. Because it allows fast recovery, it is a commonly used muscle relaxant for patients undergoing short surgical procedures. We report the case of a 5-year-old boy who underwent outpatient inguinal herniorraphy and developed unexpected prolonged neuromuscular block after the use of mivacurium. He required mechanical ventilation support in the intensive care unit because he could not attain adequate muscle power 1 hour after termination of anesthesia; the muscular paralysis persisted for 5 hours after the bolus dose of 0.3 mg/kg mivacurium. Subsequent investigation revealed an extremely low plasma cholinesterase concentration (115 U/L), and this was later determined to be a congenital condition. This is the first reported case of cholinesterase deficiency diagnosed as a result of general anesthesia in Taiwan.

Genome-wide search for loss of heterozygosity using laser capture microdissected tissue of breast carcinoma: an implication for mutator phenotype and breast cancer pathogenesis

Breast cancer is considered to display a high degree of intratumor heterogeneity, without any obvious morphological and pathological steps to define sequential evolution, and its progression may vary among individual tumors. In an attempt to elucidate these etiological and phenotypic complexities, the present study, based on the fundamental concept that genomic instability is the engine of both tumor progression and tumor heterogeneity, was conducted to test the hypothesis that breast cancer pathogenesis is driven by double-strand break (DSB)-initiated chromosome instability (CIN). The rationale underlying this hypothesis is derived from the clues provided by family breast cancer syndromes, in which susceptibility genes, including p53, ATM, BRCA1 and BRCA2, are involved within the common functional pathway of DSB-related checkpoint/ repair. Because genomic deletion caused by DSB is reflected in the genetic mechanism of loss of heterozygosity (LOH), this genome-wide LOH study was conducted, using 100 tumors and 400 microsatellite markers. To minimize the effect of heterogeneity within tumors, the experimental technique of laser capture microdissection was used to ensure that genetic and phenotypic examinations were based on the same tumor cells. Support for our hypothesis comes from the observations that: (a) the extent of DSB-initiated CIN in tumors significantly increased as tumors progressed to poorer grades or later stages; (b) in the sequential steps toward CIN, the loci of p53 and ATM, the key checkpoint genes against DSB, were lost at the earliest stage; and (c) many loci identified to be important in breast tumorigenesis were the genomic sites possibly harboring the genes involved in DSB-related checkpoint/repair (including RAD51, RAD52, and BRCA1) or CIN (including FA-A, FA-D, and WRN), and a higher number of these loci showing LOH was significantly associated with increased level of DSB-initiated CIN (P < 0.0001). Breast cancers are thus considered to be sequentially progressive with CIN. However, CIN might also cause genetic heterogeneity, which was revealed by the findings that LOH at some markers was observed only in the component of ductal carcinoma in situ but not in the invasive component of the same tumors. In addition, some markers were found to preferentially lose at specific tumor grades, implying their contribution to genetic heterogeneity during tumor development. Therefore, this study suggests that breast cancer progression is clonal with regard to CIN, but different breast cancers would present distinct molecular profiles resulting from genetic heterogeneity caused by CIN.

Metaplastic carcinoma of the breast: analysis of eight Asian patients with special emphasis on two unusual cases presenting with inflammatory-type breast cancer

Metaplastic carcinoma of the breast is a rare form of breast cancer and has an uncertain prognostic significance. Cases from Asian countries have never been reported in the English literature. Between 1983 and 1998, we encountered 8 cases in our institution. There were 7 women and one man with a median age of 52.5 (37-73) years. Pathologic diagnosis included three poorly-differentiated adenosquamous carcinomas, two adenocarcinomas with spindle cell metaplasia, two matrix-producing carcinomas and one carcinosarcoma. Estrogen receptor was positive in 2 (25%) patients. Local recurrence or distant metastasis developed in 3 patients within one year of initial treatment. With a mean follow-up of 81 months (range, 19-183 months), 5 patients were disease-free at the time of this report. Interestingly, two of our patients had presented with huge-sized inflammatory breast cancer and were refractory to neo-adjuvant chemotherapy, but enjoyed an unexpected long disease-free survival after mastectomy. Although the clinical course of our patients appeared in general similar to that of the Western series, the two patients with inflammatory breast carcinoma ran a very unusual course, which may deserve further characterization.

Activity of p44/42 MAP kinase in the caudal subnucleus of trigeminal spinal nucleus is increased following perioral noxious stimulation in the mouse

The extracellular signal-regulated protein kinase-1 and -2 (ERK1 and ERK2), also referred to as the p44/42 mitogen-activated protein kinase (p44/42 MAP kinase), plays an essential role in neuronal signal transduction, but its function involved in nociceptive response has not been deeply studied yet. Here we report immunohistochemical evidence that p44/42 MAPK might be critical in nociceptive response. We found that after formalin was injected into the perioral skin of the upper lip of mice, the number of activated p44/42 MAPK-like immunoreactive neurons was significantly increased in the laminae I and II of the caudal subnucleus of the trigeminal spinal nucleus (Sp5C). The positive neurons and fibers were mostly concentrated in the middle portion of Sp5C dorsoventrally, where the afferent fibers innervating the skin of the upper lip are terminated. The reactive products were localized in perikarya, dendrites, nuclei, and diffusely in the neuropil. The present result suggests that p44/42 MAPK may be important in the transmission and modulation of noxious information in Sp5C.

Interdental distraction osteogenesis and rapid orthodontic tooth movement: a novel approach to approximate a wide alveolar cleft or bony defect

The closure of a wide alveolar cleft and fistula in cleft patients and the reconstruction of a maxillary dentoalveolar defect in traumatic patients are challenging for both orthodontists and surgeons. This is due to the difficulty in achieving complete closure by using local attached gingiva and the great volume of bone required for the graft. In this article, the authors propose using interdental distraction osteogenesis to create a segment of new alveolar bone and attached gingiva for the complete approximation of a wide alveolar cleft/fistula and the reconstruction of a maxillary dentoalveolar defect. They performed this procedure on one patient with a traumatic maxillary dentoalveolar defect and 10 patients with unilateral or bilateral cleft lips and palates who had varied dentoalveolar clefts/fistulas. Interdental and maxillary osteotomies were performed on one side of the dental arch by the cleft or defect. After a latency period of 3 days, the osteotomized distal segment of the dental arch was then distracted and transported toward the cleft or defect by using a toothborne intraoral distraction device. The alveoli and gingivae on both ends of the cleft or defect were approximated after distraction osteogenesis. The need for extensive alveolar bone grafting was eliminated. A segment of new edentulous alveolus and attached gingiva was created interdentally at a site distant to the cleft or defect. In the cleft patients, teeth were moved orthodontically into the regenerate (newly formed alveolar bone) dental crowding 1 week after distraction. The orthodontic tooth movement was rapidly completed in 3 months, and the edentulous space was eliminated. Interdental distraction osteogenesis minimizes an alveolar cleft/fistula and helps reconstruct a maxillary dentoalveolar defect by approximating the native alveoli and gingivae; it also creates new alveolar bone and gingiva for rapid orthodontic tooth movement.

Ion channel modulation as the basis for neuroprotective action of MS-153

MS-153, (R)-(-)-5-methyl-1-nicotinoyl-2-pyrazoline, is a new neuroprotective drug. Recent data in the literature suggest that it inhibits glutamate accumulation occurring during ischemia and the translocation of protein kinase C gamma (PKC gamma). The present study was undertaken to prove the hypothesis that MS-153 blocks neuroreceptors and ion channels involved in glutamate accumulation. Neurons isolated from rat dorsal root ganglia and frontal cortex were used for recording channel currents by the whole-cell patch clamp technique. The effects of bath-applied MS-153 were examined on tetrodotoxin-sensitive and tetrodotoxin-resistant sodium channels and high voltage-gated calcium channels of dorsal root ganglion neurons, and channels activated by glutamate, N-methyl-D-aspartate (NMDA), kainate, alpha-amino-3-hydroxy-5-methyl-4-isoxarole propionic acid (AMPA), gamma-aminobutyric acid (GABA) and acetylcholine (ACh) in cortical neurons. MS-153 at a concentration of 300 microM had no effect on either tetrodotoxin-sensitive or tetrodotoxin-resistant sodium channels. High voltage-gated calcium channels were either suppressed or not affected by 1-300 microM MS-153. The variable blocking effect of MS-153 was due to the variable activity of intracellular components in individual neurons, especially that of PKC, whose translocation is known to be inhibited by MS-153. When 100 nM phorbol 12-myristate-13-acetate (PMA) was applied to neurons, MS-153 suppressed the calcium channel current more frequently. Calphostin C (0.5 microM), a specific PKC inhibitor, applied intracellularly via recording patch pipette, completely abolished MS-153 suppression of the calcium channel current. Currents induced by glutamate, NMDA, kainate, AMPA, GABA or ACh were not affected by MS-153 at 300 microM. It was concluded that MS-153 inhibited high voltage-gated calcium channels through interactions with PKC, thereby preventing massive release of glutamate from nerve terminals in ischemic conditions.

Characterization of an allelic variant in the nifedipine-specific element of CYP3A4: ethnic distribution and implications for prostate cancer risk. Mutations in brief no. 191. Online

CYP3A4 is involved in the metabolism of numerous biologically active compounds, including testosterone. A genetic variant located in the P450NF (nifedipine) specific element (NFSE) has been identified that disrupts a transciptional regulatory element located in the 5' regulatory region of CYP3A4. The CYP3A4 variant (CYP3A4-V) is associated with the clinical presentation of prostate cancer. There are significant differences in CYP3A4 metabolism and rates of prostate cancer across ethnic groups that may be associated with CYP3A4 genotypes. Therefore, we estimated the frequency of the CYP3A4 variant in three ethnic groups with different prostate cancer incidence rates. The frequency (q) of CYP3A4-V was significantly different (p<0.0001) in African Americans (q=0.53), U.S. Caucasians (q=0.09), and Taiwanese (q=0.0). CYP3A4-V segregated in a Mendelian manner in one large African American family, and 7 of 16 (44%) biologically unrelated "marry-ins" carried a CYP3A4 variant allele. Reflecting population-specific prostate cancer incidence rates, our results suggest a high frequency of this variant in African Americans compared with U.S. Caucasians and Taiwanese.

Changes in portal venous hemodynamics in patients with severe acute hepatitis over one year

PURPOSE

A wide range of portal vein blood flow velocity (PVV) values can be found in acute hepatitis. We studied course and medical significance of PVV changes in patients with severe acute hepatitis over a 1-year period.

METHODS

Portal venous hemodynamics were studied by Doppler sonography in 90 patients at study enrollment and 3, 6, and 12 months following an episode of severe acute hepatitis.

RESULTS

Forty-one survivors who had a maximum PVV at enrollment greater than or equal to the value measured at the third month were classified as the "declining PVV" group. Thirty-six survivors who had a maximum PVV at enrollment less than the value measured at the third month were classified as the "rising PVV" group. Thirteen patients died of acute hepatic failure and were classified as the fatality group. The fatality group had significantly lower maximum PVV, worse liver biochemical test results, and a higher prevalence of ascites at enrollment. In contrast, the declining PVV group showed significantly better liver biochemical test results and a lower prevalence of ascites. There was no significant difference in portal vein blood flow between the rising and declining PVV groups since portal vein diameter increased while PVV decreased.

CONCLUSIONS

An initially decreased PVV can be found in some patients with severe acute hepatitis and is inversely correlated with the severity of liver damage.

Nerve growth factor signaling in caveolae-like domains at the plasma membrane

Nerve growth factor (NGF) binding to its receptors TrkA and p75(NTR) enhances the survival, differentiation, and maintenance of neurons. Recent studies have suggested that NGF receptor activation may occur in caveolae or caveolae-like membranes (CLM). This is an intriguing possibility because caveolae have been shown to contain many of the signaling intermediates in the TrkA signaling cascade. To examine the membrane localization of TrkA and p75(NTR), we isolated caveolae from 3T3-TrkA-p75 cells and CLM from PC12 cells. Immunoblot analysis showed that TrkA and p75(NTR) were enriched about 13- and 25-fold, respectively, in caveolae and CLM. Binding and cross-linking studies demonstrated that the NGF binding to both TrkA and p75(NTR) was considerably enriched in CLM and that about 90% of high affinity binding to TrkA was present in CLM. When PC12 cells were treated with NGF, virtually all activated (i.e. tyrosine phosphorylated) TrkA was found in the CLM. Remarkably, in NGF-treated cells, it was only in CLM that activated TrkA was coimmunoprecipitated with phosphorylated Shc and PLCgamma. These results document a signaling role for TrkA in CLM and suggest that both TrkA and p75(NTR) signaling are initiated from these membranes.

Breast cancer risk associated with genotype polymorphism of the estrogen-metabolizing genes CYP17, CYP1A1, and COMT: a multigenic study on cancer susceptibility

Estrogen has been proposed to trigger breast cancer development via an initiating mechanism involving its metabolite, catechol estrogen (CE). To examine this hypothesis, we conducted a multigenic case-control study to determine whether polymorphisms of the genes responsible for CE formation via estrogen biosynthesis (CYP17) and hydroxylation (CYP1A1) and CE inactivation (COMT) are associated with an elevated risk for breast cancer in Taiwanese women, and whether the association between genotype and risk may be modified by estrogen exposure. One hundred and fifty breast cancer patients and 150 healthy controls were recruited. PCR-based RFLP assays were used to determine the genotypes of estrogen-metabolizing genes. The breast cancer risk associated with individual susceptibility genotypes varied among the three genes and was highest for COMT, followed by CYP1A1 and CYP17. After simultaneous consideration of all three genes and other well-established risk factors of breast cancer, the COMT genotype remained the most significant determinant for breast cancer development and was associated with a 4-fold increase in risk (95% confidence interval, 1.12-19.08). Furthermore, a trend of increasing risk for developing breast cancer was found in women harboring higher numbers of high-risk genotypes (P = 0.006), including the high activity CYP17 (CYP17 A2/A2), high inducibility CYP1A1 (CYP1A1 MspI vt/vt), and low activity COMT (COMT L/L) genotypes. The association of risk with the number of susceptibility genotypes was stronger in women with prolonged estrogen exposure (indicated by a higher number of estrogen exposure years or a higher number of estrogen exposure years between menarche and first full-term pregnancy), women with higher estrogen levels (implied by early menarche), and women with a higher body mass index (> or = 22.5). On the basis of comprehensive profiles of estrogen metabolism, this study supports the possibility that breast cancer can be initiated by estrogen exposure.