A synchrotron radiation beam-position monitor at the Taiwan Light Source

A prototype photon-beam-position monitor has been designed, fabricated and tested at the Taiwan Light Source of the Synchrotron Radiation Research Center. Aluminium was chosen as the material of the blade electrodes due to its low atomic number and high thermal conductivity. The resolution of this photon-beam-position monitor was <+/-1 micro m. The sensitivity of the blade electrode has been measured in situ. Results of measurements for bending-magnet light and undulator light with different gaps are described.

Factors related to adolescents' perceptions of treatment outcomes in an adolescent health clinic

To determine factors related to adolescents' perceived treatment outcomes of their health problems in an adolescent health clinic located at a college hospital, 246 adolescent patients between the ages of 11 and 21 who visited the clinic twice or more during the period January 1994 to December 1995 were included in this study. Information concerning adolescents' sociodemographic characteristics, family function, office visits and health problems of first visits was collected by reviewing subjects' medical and other clinic-related records. In addition, a structured questionnaire was mailed to assess subjects' satisfaction with physicians and the environment and services provided by the clinic as well as their perceived treatment outcomes. 148 patients completed the questionnaire, a response rate of 60.2%. Most of the respondents were in late-stage adolescence (71.0%) and were in school (71.0%). About half of respondents had normal family function, while the other half had moderate or severe family dysfunction. Most of the health problems of respondents were acute (64.2%) and were biological (76.4%) conditions. Most of the respondents were satisfied with the various characteristics of physicians except confidentiality emphasized by the physicians, while many fewer respondents were satisfied with the environment and services provided by the clinic. Family function, physicians' respect toward the adolescents, and the adolescents' satisfaction with the services provided in general were the factors significantly related to adolescents' perceived treatment outcomes based on a stepwise, multiple logistic regression analysis. We conclude that efforts to provided could result in better adolescent perceived treatment outcomes.

Systematic design of full phase compensation microprism-type low-loss bent waveguides

For traditional microprism-type bent waveguides one must take into consideration only the two outer optical paths to compensate for the phase difference between phase fronts in front of and behind the bent region. We propose a systematic design rule to achieve an optimal phase matching condition by taking account of the whole optical paths for full phase compensation. The simulated results obtained with the fast Fourier transform beam propagation method indicate that the normalized transmitted powers are greater than 95% even though the bent angle is as large as 10 degrees .

Bringing mind-body medicine into the mainstream

Centuries-old concepts concerning the mind's influence on the body are being examined with renewed interest. As awareness of the health benefits of being able to voluntarily control vital aspects of the metabolic state increases, and as our understanding of the underlying molecular mechanisms of such control also increases, mind-body medicine may move further into the mainstream of Western medical practices.

Using prostate-specific antigen to eliminate the staging radionuclide bone scan

Traditionally the radionuclide bone scan has been the cornerstone of prostate cancer staging. Previous widespread use of bone-scan imaging was certainly reasonable, even in the asymptomatic patient, as clinicians had no methodology to predict who would or who would not have osseous metastases. Now, in the era of PSA testing, clinicians do have a timely, cost-effective method to determine those patients who are highly unlikely to have osseous metastases. As evidenced by several clinical studies noted previously, a radionuclide bone scan should not be obtained in staging the asymptomatic, newly diagnosed prostate cancer patient with a serum PSA level less than or equal to 10 ng/mL. Incorporation of clinical stage and tumor grade does not significantly improve the predictive value of PSA. Those patients with bone discomfort, however, should undergo bone imaging, regardless of the serum PSA level. Similarly, the serum PSA level may be used to avoid unnecessary bone-scan imaging in the patient with recurrent prostate cancer following definitive treatment. At this time, we do not have enough clinical information to determine the optimal PSA level that will predict precisely which patients will have osseous metastases. From the above reports, however, and the present authors' clinical experience, it would seem reasonable to avoid bone-scan imaging if the post-radical prostatectomy serum PSA level is not more than 2 ng/mL. No absolute data are available about recurrence after radiation therapy or for men being managed with watchful waiting. In an attempt to clarify this issue, there is currently a clinical study underway at the University of Michigan. This study assesses the minimum serum PSA elevation that necessitates bone imaging in restaging the asymptomatic patient with recurrent prostate cancer after radical surgery or definitive radiation therapy. The radionuclide bone scan continues to be the gold standard for the detection of osseous metastases in prostate cancer. Nevertheless, it is unnecessary in the specific situations outlined above. Serum PSA testing allows the physician to refine the use and application of this imaging study, thus providing an opportunity to eliminate expensive and time-consuming studies that ultimately do not contribute additional information. The national economic impact of doing so is tremendous.

Prediction of clinical course in patients with idiopathic erythrocytosis by endogenous erythroid colony assay but not by serum erythropoietin levels

We studied the in vitro culture growth of bone marrow and blood erythroid progenitors and serum erythropoietin (EPO) levels by radioimmunoassay in 24 patients with idiopathic erythrocytosis (IE). All patients had an increased red blood cell (RBC) mass and lacked a cause of secondary polycythemia, but did not fulfill the diagnostic criteria of polycythemia vera (PV). Marrow and blood cultures were obtained simultaneously; the results of endogenous (EPO-independent) erythroid colony (EEC) growth were parallel in both cultures. EECs were present in five patients, all of them developed PV 3 to 48 months later. The EEC number did not correlate with the time to the progression of PV. In contrast, none of the 19 EEC-negative patients had PV evolution during a median follow-up period of 38 months. Three of the five IE patients in whom EECs formed displayed vascular complications during their clinical course compared with three of 19 patients who did not have EEC. The serum EPO levels were variable: low in five, normal in 14, and high in five patients. Serial measurements of serum EPO levels in three of five patients who had high initial levels showed persistently elevated values; the underlying cause of the increased EPO production could not be defined during a follow-up period of more than 36 months. Of the five patients who subsequently developed PV, two had low serum EPO levels and three had normal values at initial evaluation. Serum EPO levels did not correlate with the occurrence of thrombotic complications. Our results show that serum EPO levels have limited value in determining the underlying cause of IE and cannot predict the clinical course of patients with IE, whereas the assessment of EEC in bone marrow or blood can identify IE patients who will have PV evolution.

Genetic immunotherapy of established tumors with adenovirus-murine granulocyte-macrophage colony-stimulating factor

Increased local production of granulocyte-macrophage colony-stimulating factor (GM-CSF) by genetically modified tumor cells can induce specific antitumor cellular immunity. We constructed a recombinant adenovirus expressing murine GM-CSF and tested it for therapeutic efficacy in a syngeneic murine lung cancer model system. In vitro transduction of Lewis lung carcinoma cells with adenovirus-mGM-CSF suppressed tumor formation in syngenic mice (C57BL/6), and transduced and irradiated Lewis lung carcinoma cells induced regression of pre-established wild-type tumors without in vitro selection for transductants. Low, but significant, levels of specific antitumor cytotoxic T lymphocytes (CTL) were observed in mice inoculated with GM-CSF but not with reporter virus-transduced tumor cells. GM-CSF-transduced cells induced the accumulation of dendritic cells at the site of tumor, consistent with a mechanism involving improved tumor antigen presentation. These data suggest that transduction of tumor cells with recombinant GM-CSF adenovirus may be an effective and practical cancer gene therapeutic strategy.

[Clinical experience of automated double filtration plasmapheresis]

Double filtration plasmapheresis, one kind of fractionation plasmapheresis, was developed from membrane type plasmapheresis to remove only the pathogen and return the normal protein back to the patient. We started our automated double filtration plasmapheresis since December 1993. There were 13 patients who received one hundred treatments totally during one year period. And they are myasthenia gravis (8 patients); acute inflammatory demyelinating polyneuropathy (1 patient), multiple myeloma (1 patient); acquired factor VIII inhibitor (1 patient); autoimmune hemolytic anemia (1 patient); systemic lupus erythematous (1 patient). Technically double filtration plasmapheresis is easy to perform and time-saving. It also makes necessity of replacement fluid less frequent. Incidence of complication is rare, and this includes hypotension 2%, palpitation 1%, headache 1%, hemolysis 4%, air emboli 1%, high secondary pressure 2%, and no motality during our treatment. Clinical response is documented in cases of myasthenia gravis; acute inflammatory demyelinating polyneuropathy and acquired factor VIII inhibitor in our study. In conclusion, double filtration plasmapheresis is a time-saving, convenient, and safe therapeutic modality with rare complication. Because its effectiveness on limited kinds of diseases and costs relatively high price, thus plasmapheresis should be used in selected cases and treat aggressively if indicated.

Burns in prisoners: an assessment of problems in handling prisoners in a burns unit

All burns units look after members of the prison population at times. This can cause anxiety among the staff and unique problems with management. Four cases-were reviewed from Her Majesty's Prison (HMP) Perth, Scotland, all of whom required resuscitation, and a survey undertaken of the nursing staff in our unit to assess attitudes to caring for burns prisoners in particular. Despite a careful search of the literature, no reference to the problems of managing prisoners in a burns unit could be found. However, it was found that the handling of violent offenders can be a significant cause of anxiety for nursing staff, and the presence of prison officers a reassurance rather than a hindrance in the management of burned prisoners. It is therefore recommended that prison officers be present at all times while managing burned prisoners.

Increased immunogenicity of tumors bearing mutant p53 and P1A epitopes after transduction of B7-1 via recombinant adenovirus

The majority of human solid tumors are likely to express protein epitopes which can act as targets for cytotoxic T cells, but these are frequently not effectively recognized. We tested whether the introduction of the costimulatory molecule B7-1 using a recombinant adenovirus (Ad-B7) can result in effective induction of epitope-specific immunity in two tumor models that express defined endogenous protein epitopes: D459, a fibroblast-derived cell line transfected with a human missense mutant p53 (C to Y at position 135), and P815, a mastocytoma expressing the endogenous tumor epitope P1A. Under the conditions studied, both of these tumors grow and kill their hosts without evidence of significant immune rejection. However, after transduction with the adenovirus containing B7-1, both of these tumors lose tumorigenicity and elicit specific cellular immunity to the mutant p53 epitope in D459 and P1A in P815. In addition, animals exposed to B7-transduced tumor cells were protected from subsequent challenge with nontransduced tumor. Adenovirus has distinct advantages for this approach, as it has high infectivity not requiring in vitro culture, low lytic potential, and transient expression of sufficient duration for immunologic effectiveness but without significant concern over permanent genetic modification. We conclude that transduction of tumor cells with Ad-B7 can increase the immunogenicity of endogenous protein epitopes and may represent a practical therapeutic approach to system human cancers.

Antitumor effects of an adenovirus expressing antisense insulin-like growth factor I receptor on human lung cancer cell lines

Insulin-like growth factors (IGFs) are often essential for the maintenance of the malignant phenotype, and in lung cancer the IGF-I receptor (IGF-Ir) is often expressed at high levels. Stable transfection of antisense plasmids expressing the first 300 bp of the IGF-Ir reduces the tumorigenicity of a variety of tumor cell lines and has been reported to induce systemic antitumor effects on established, non-gene-modified tumors in animal model systems. We have constructed an adenovirus expressing an antisense IGF-Ir (Ad-IGF-Ir/as) in an attempt to develop these observations into a clinical therapeutic approach. A single transduction by Ad-IGF-Ir/as (at a multiplicity of infection of 10:1) decreased the IGF-Ir number by about 50% in human lung cancer cell lines NCI H460 and SCC5, as measured by an 125I-labeled IGF-I competitive binding assay. After the transduction of these human lung cancer cell lines by Ad-IGF-Ir/as, the soft agar clonogenicity was reduced by 84%. The i.p. treatment of nude mice bearing established i.p. NCI H460 cells resulted in prolonged survival compared to that of nude mice treated with a reporter virus. These results suggest that Ad-IGF-Ir/as has a therapeutic effect on established human lung cancer xenografts and may represent an effective and practical cancer gene therapy strategy.

Risk factors for pancreatic cancer in orientals

In order to assess what the risk factors for patients with pancreatic cancer (PC) in Taiwan are, a retrospective study was undertaken among 282 consecutively enrolled inpatients with confirmed pancreatic cancer within the past 5 years. For comparison, 282 age- and sex-matched controls were consecutively enrolled. A history of smoking, consumption of alcohol, diabetes mellitus, cholecystectomy and gastric surgery were thoroughly reviewed. Smoking and diabetes mellitus were very common among patients with pancreatic cancer compared with controls (P < 0.01). A significant linear trend towards an increased odds ratios (OR) for the development of PC with a higher level of smoking was seen (P < 0.001). Diabetes mellitus (DM) also exhibited an increased risk (OR: 2.84; P < 0.01), while the risk still existed among those patients who had a diabetic history of more than 3 years. Among 129 histologically established PC patients, smoking remained as a risk factor for PC, while the linear trend with an increasing OR with increasing levels of smoking was confirmed again (P < 0.01). DM, particularly over the long-term, was also a risk factor for those histologically established PC patients. In summary, cigarette smoking and existing diabetes mellitus are probable risk factors for the development of pancreatic cancer in Taiwan.

An assembled electrogastrographic device to examine the meal effect on gastric slow wave

We have assembled an electrogastrographic device based on the main components of amplifiers, a band-pass filter, an analogue/digital converter, low band-pass digital filters and a personal computer. The analysis software uses autoregressive moving average modelling to compute the frequency of slow waves and uses fast Fourier transformation for power spectral computation. Twenty healthy young male volunteers were enrolled in the study to test meal-elicited responses of the slow wave. Subjects underwent a 15 min recording while fasting and then a standard breakfast, which included 250 mL milk and a cake with a total of 1.45 kj, was ingested within 5 min. The post-prandial 15 min recording was immediately resumed after the meal. A slight but significant increase in the frequency of slow waves was seen in post-prandial measurement (mean +/- s.d., 0.0506 +/- 0.0005 vs 0.0497 +/- 0.0005 Hz; P < 0.0001). Moreover, a significant enhancement of the power of slow waves was elicited following the meal (36.0 +/- 3.1 vs 27.6 +/- 3.1 dB; P < 0.0001). We conclude that this assembled electrogastrographic device is a reliable means of monitoring gastric myoelectrical activity because the phenomenon of post-prandial responses of slow waves in either frequency or power is well demonstrated.

Alteration of distal esophageal motor functions on different body positions

BACKGROUND/AIMS

This study tried to resolve whether changed body position influences esophageal manometric parameters.

MATERIAL AND METHODS

A pneumohydraulic infusion system was employed to measure esophageal parameters for 32 healthy volunteers. They underwent two consecutive manometries on both supine and sitting positions in a random order. These motility measurements included lower esophageal sphincter pressure, dry/wet swallow induced contractile amplitude and interval of distal esophageal body, and its peristaltic speed.

RESULTS

Sitting position evoked a higher lower esophageal sphincter pressure than the supine measurement (Mean +/- SD: 14.6 +/- 4.0 mmHg vs. 11.9 +/- 4.2 mmHg, p < 0.01). At the distal esophagus, a swallow led to a stronger contractile amplitude and longer interval on supine measurement.

CONCLUSIONS

Recorded peristaltic speeds in various esophageal segments resulted in a difference while this result was mainly due to the different recorded body positions (p < 0.01). Partial esophageal manometric parameters recorded on sitting position are different from the supine measurement. Hence altered body position may modulate some distal esophageal motor functions.

The effect of cimetidine on serum acidic markers and Helicobacter pylori in gastric ulcer subjects

BACKGROUND

This study was conducted to investigate the influence of cimetidine on the Helicobacter [correction of Helilcobacter] pylori(HP) colonization and serum acidic markers in gastric ulcer patients.

METHODS

Forty-eight patients with gastric ulcer confirmed by endoscopy were consecutively enrolled. HP colonization was confirmed by either urease test or histological examination. Fasting serum gastrin and pepsinogen I (PGI) levels were measured before and after 8 weeks of cimetidine treatment.

RESULTS

Healing of ulcer at the end of treatment was 75%. Initially, the infection rate of HP was 87.5% (42/48). After 8 weeks of treatment, HP clearance rate was only 7.1% (3/42). A significant elevation of serum gastrin level was seen in HP positive subjects after treatment (86.3 +/- 22.2 pg/ml vs. 103.1 +/- 44.36 pg/ml, p <0.05) while HP negative patients did not show the effect. There was no significant change in the mean serum PGI concentration before and after cimetidine treatment (91.5 +/- 36.6 ng/ml vs. 95.6 +/- 43.8 ng/ml, NS).

CONCLUSIONS

Cimetidine is not able to clear HP despite its good efficacy in healing gastric ulcers. HP should play an important role in the elevation of serum gastrin levels during cimetidine therapy while serum PGI levels are not influenced by the antisecretory ability of cimetidine.

Polycystic ovary syndrome: pathophysiology and outcome with in vitro fertilization

OBJECTIVE

To assess the efficacy of IVP-ET in infertile women with the polycystic ovary syndrome (PCOS) and to provide a comprehensive review of contemporary therapeutic options and their complications as reflected in the current literature.

DESIGN

Pertinent studies in medical literature identified through computerized bibliographic search and via manual review of relevant scientific publications.

RESULTS

In vitro fertilization and ET is an effective therapy for PCOS patients who are refractory to ovulation induction in vivo or who have coexisting infertility factors. The use of GnRH agonist (GnRH-a) is associated with significant reductions in the incidence of pregnancy loss and may improve fertilization and cleavage rates. In the PCOS patient, the use of purified FSH preparations does not appear to improve pregnancy rates nor other clinical parameters when compared with hMG. Severe ovarian hyperstimulation syndrome (OHSS) is an important consideration when PCOS patients undergo superovulation protocols. Strategies for OHSS prevention include the use of intravenous albumin immediately after oocyte retrieval, triggering of ovulation with a GnRH-a, or withholding menotropin therapy for several days before hCG administration. Cryopreservation of all embryos for future transfer in an artificial cycle has also proven to be an effective alternative in PCOS patients at high risk for severe OHSS.

CONCLUSIONS

Pregnancy rates for PCOS patients undergoing IVF-ET are comparable with those for women with tubal factor infertility. Therefore, IVF-ET should be offered to patients with PCOS who are refractory to conventional infertility modalities.

[Community-based cervical cancer screening in seven townships in Taiwan]

Cervical cancer is the leading malignant neoplasm in women in Taiwan. In order to compare the validity of various cervical neoplasia screening methods, estimate the prevalence of low- and high-grade squamous intraepithelial lesions (LSIL and HSIL), and identify risk factors for LSIL and HSIL, a community-based cervical neoplasia screening program was implemented in Sanchi, Chutung, Potzu, Kaohsu, Makung, Huhsi, and Paihsa townships, Taiwan. Both cervical smears and cervicograms were used for the screening of cervical neoplasia. Subjects who had positive cervical smears, cervicogram, or both, were further confirmed by colposcopy-guided biopsy. A total of 10,628 married women aged 30 to 64 years were recruited from seven study townships which gave a response rate of 25.2%. Among 667 subjects who screened positive, 555 (82%) underwent colposcopy-guided biopsy. The age-adjusted prevalence was 3.4% for LSIL and 1.7% for HSIL. The biopsy-confirmed rates for cervical smear-detected LSIL and HSIL were 62.8% and 80.6%, respectively; while 56.6% of minor lesions and 22.2% of major lesions identified by cervicogram were biopsy-confirmed as LSIL and HSIL, respectively. The sensitivity of detecting LSIL was higher for cervicograms (79.3%) than for cervical smears (16.7%), and cervicograms had a lower sensitivity in detecting HSIL (48.4%) than cervical smears (90.0%). Multiple logistic regression analysis showed a striking geographical variation in prevalence of LSIL and HSIL. The prevalence of LSIL decreased with the increase in age, and increased with the duration of taking oral contraceptives. The prevalence of HSIL increased with the parity and the duration of taking oral contraceptives and was also significantly associated with the history of cervical cancer among mother and sisters. It is suggested that improvements in the participation rate of cervical neoplasia screening would promote women's health in Taiwan.

Pseudomelanosis duodeni: report of eight cases

Pseudomelanosis duodeni is an uncommon endoscopic sign characterized by diffuse small black spots on the first and second portions of the duodenum. It occurs predominantly in female and elderly patients and is linked to chronic illnesses and related medications. Between 1988 and 1994, the authors saw eight patients with pseudomelanosis duodeni. To evaluate the nature of the pigments, special staining was performed in seven cases. Iron stain was strongly positive in three cases. Electron microscopy was performed in two cases. This revealed amorphous bodies within macrophage lysosomes in one case and angular crystals in another case. These tests suggest that in pseudomelanosis duodeni iron metabolism may be impaired and iron is pooled within macrophages.

Gene therapy for lung cancer

Lung cancer is a leading cause of cancer death and standard chemotherapies are resulting in only marginal improvements in outcome. Experimental approaches involving gene therapy are attractive in this clinical setting. There are two basic types of genes utilized, either those intended to induce immunity or those that are directly tumoricidal. Immunity-inducing genes that have been used in model (and some human) systems include MHC molecules, costimulatory molecules, and cytokines such as IL-2, IL-4, IL-6, GM-CSF. These are intended to induce effective systemic immune responses against tumor antigens which would not otherwise develop. Direct toxic approaches include the reintroduction of tumor suppressor genes or enzymes which convert non-toxic drugs to toxic ones, such as herpes thymidine kinase. As a means for gene delivery, retroviruses are the most common vehicle, although Adenovirus vectors and direct DNA delivery have specific advantages.

Diagnostic markers of prostate cancer: utility of prostate-specific antigen in diagnosis and staging

The optimal tumor marker for prostate cancer would be effective for early detection, staging, and monitoring patients after definitive treatment. This marker would have a high sensitivity, specificity, and positive predictive value for distinguishing men with benign prostatic hyperplasia (BPH) from men with early prostate cancer. Such a marker would consistently detect biologically significant disease, correlate with clinical and pathologic staging, and predict prognosis. In addition, this marker would be accurate at indicating cure or progression of disease after treatment. Certainly, the ideal marker also would be reproducible, inexpensive, generate results rapidly, be easy to perform, be accessible to clinicians, and tolerable to patients. Unfortunately, such a "super" marker does not exist at this time. However, prostate-specific antigen (PSA) has many of the aforementioned capabilities. This article will describe the current utility of PSA in the diagnosis and staging of prostate cancer.