Evaluation of dose conversion coefficients for external exposure using Taiwanese reference man and woman

Reference man has been widely used for external and internal dose evaluation of radiation protection. The parameters of the mathematical model of organs suggested by the International Commission of Radiological Protection (ICRP) are adopted from the average data of Caucasians. However, the organ masses of Asians are significantly different from the data of Caucasians, leading to potentially dosimetric errors. In this study, a total of 40 volunteers whose heights and weights corresponded to the statistical average of Taiwanese adults were recruited. Magnetic resonance imaging was performed, and T2-weighted images were acquired. The Taiwanese reference man and woman were constructed according to the measured organ masses. The dose conversion coefficients (DCFs) for anterior-posterior (AP), posterior-anterior (PA), right lateral (RLAT) and left lateral (LLAT) irradiation geometries were simulated. For the Taiwanese reference man, the average differences of the DCFs compared with the results of ICRP-74 were 7.6, 5.1 and 11.1 % for 0.1, 1 and 10 MeV photons irradiated in the AP direction. The maximum difference reached 51.7 % for the testes irradiated by 10 MeV photons. The size of the trunk, the volume and the geometric position of organs can cause a significant impact on the DCFs for external exposure of radiation. The constructed Taiwanese reference man and woman can be used in radiation protection to increase the accuracy of dose evaluation for the Taiwanese population.

Dynamic phase evaluation in sparse-sampled temporal speckle pattern sequence

The rapid progress of modern manufacturing technology has posed stringent requirements for inspecting techniques for vibration characterization and dynamic testing. Because of its simplicity, accuracy, and whole-field character, speckle interferometry has served as one of the major techniques for dynamic measurement, where normally a dense-sampled temporal speckle sequence is captured for phase retrieval using Fourier or wavelet transforms. In this Letter, a method is proposed for phase evaluation of sparse-sampled speckle patterns when the sampling rate is lower than two points per temporal cycle. Dynamic experiments using a high-speed camera demonstrated the effectiveness of the proposed method for complicated wrapped phase retrieval in electronic/digital speckle pattern interferometry.

Combination of multiple mRNA markers (PTTG1, Survivin, UbcH10 and TK1) in the diagnosis of Taiwanese patients with breast cancer by membrane array

OBJECTIVE

Early detection is a prerequisite to the effective reduction of morbidity and mortality from breast cancer. The present study intended to employ a high-throughput membrane array to detect a panel of mRNA markers expressed by circulating tumor cells (CTCs) in the peripheral blood of female patients with breast cancer.

METHODS

Peripheral blood was sampled from 92 breast cancer patients and 100 normal persons. CTCs were detected by using a membrane array technique. The markers used included the pituitary tumor transforming gene 1, survivin, UbcH10 and thymidine kinase 1.

RESULTS

The results showed that the membrane array could positively detect 5 cancer cells per 1 ml of peripheral blood in breast cancer cell dilution experiments. For the panel of 4 mRNA markers, sensitivity and specificity were elevated up to 86 and 88%, respectively. Furthermore, it was found that the patients' clinicopathological characteristics tumor size (p = 0.006), histologic grade (p = 0.012), lymph node metastasis (p = 0.001) and TNM stage (p = 0.006) significantly correlated with the positive detection rate of the multimarker panel.

CONCLUSIONS

These findings demonstrated that our multimarker membrane array method could detect CTCs in the circulation of breast cancer patients with considerably high sensitivity and specificity.

Simultaneous detection of multiple mRNA markers CK19, CEA, c-Met, Her2/neu and hMAM with membrane array, an innovative technique with a great potential for breast cancer diagnosis

The objective of this study was mainly to develop and evaluate a membrane array-based method simultaneously detecting the expression levels of a multiple mRNA marker panel in the peripheral blood for used in complementary breast cancer diagnosis. The mRNA markers employed included cytokeratin 19 (CK-19), carcinoembryonic antigen (CEA), c-Met, Her2/neu, and mammaglobin (hMAM). The specimens of peripheral blood were collected from 80 healthy women and 102 female patients with breast cancer. The expression levels of molecular markers were evaluated by real-time Q-PCR and membrane array. Data obtained from real-time Q-PCR and membrane array were subjected to linear regression analysis, revealing that there was a high degree of correlation between the results of these two methods (r=0.979, P<0.0001). The result of membrane array assay with a combined panel of five mRNA markers was demonstrated to achieve sensitivity of 80.6%, and specificity of 83.8% for breast cancer detection, much higher than those of analysis of single marker. In addition, we demonstrated that the membrane array method could detect circulating cancer cells at a density as low as five cancer cells per 1 ml of blood. The analysis of correlation between the outcome of membrane array and clinicopathological characteristics indicated that overexpression of the multiple marker panel was significantly correlated with tumor size (P=0.030) and TNM stage (0.009). In conclusion, the detection of circulating cancer cells by means of membrane array simultaneously monitoring five mRNA markers could significantly enhance the sensitivity and specificity for cancer cell detection.

High frequency of frameshift mutation on p53 gene in Taiwanese with non small cell lung cancer

Extensive researches have found that the mutation of p53 tumor suppressor gene is the most frequent event in many human cancers and associated with a poor clinical outcome in lung cancer patients. Because the p53 molecular mutation involved in tumorigenesis of patients with lung cancer in Taiwan remains poorly defined, the aim of this study was to assess the p53 mutation spectrum and possible etiological factors of Taiwan's patients with Non-Small Cell Lung Cancer (NSCLC). Cancer specimens were obtained surgically from 61 patients with pathologically proven NSCLC. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and direct sequencing were used to study p53 mutations in exon 4-8. We also performed immunohistochemistry (IHC) to detect p53 protein expression. Our results provided that 34 mutations of p53 gene were found in 27 cases with a mutation rate of 44% (27/61). There were six cases having more than two p53 mutations. Among the 34 mutations, 19 were point mutations (56%, 19/34) consisted of a majority of missense mutations including transversion (13/19, 68%) and transitions (6/19, 32%) with four cases (4/6, 67%) occurring in the CpG sequence. One of the most important finding in our study was the high frequency of frameshift (44%, 15/34) which included 11 insertions and 4 deletions of p53 in NSCLC in Taiwan. Surprisingly, our results disclosed distinct novel mutations at codon 181, 185, 208 (Exon 5-6) of p53. Especially, 4 cases with mutation at codon181 and codon 185 seemed to have more advanced clinical outcome with survival time less than 6 months. In addition, there were two recurring mutations at codon 168 and three at condon193. The different mutation spectrum in our series, including a high frequency of frameshift mutations and distinctly novel hot spots suggested the heterogenous entity of exogenous mutagens in NSCLC in Taiwan.

High-Tc SQUID magnetocardiography imaging system

We set up a high-Tc SQUID system for magnetocardiography (MCG) in a moderately magnetically shielded room. The electronically balanced gradiometer consists of superconducting quantum interference device (SQUID) magnetometer. One reference SQUID was mounted above the sensing SQUID while the sensing SQUID is seated at the bottom of the cryostat. The baseline of the gradiometer is varied from 5 cm to 7 cm. The output of the MCG signal was filtered with the band pass filter (0.5 - 40 Hz) and the power-line filter. The MCG system was used to detect the magnetic signal of the human heart. Equivalent current sources were used to study the inverse problem.

The long-term effects of single peritonitis episodes on peritoneal equilibration test results in continuous ambulatory peritoneal dialysis patients

The present study evaluates the long-term effects of single peritonitis episodes on peritoneal equilibration test (PET) results in continuous ambulatory peritoneal dialysis (CAPD) patients. Twenty-five patients (10 men, 15 women) with a mean age of 37.4 +/- 18.7 years were enrolled in this study because all had uneventful peritoneal dialysis periods for more than one year after a first peritonitis episode. Data from a total of 69 PETs were available [25 from before the first peritonitis episode (initial PET), 23 within 1 year after the episode (1-year PET), and 21 within 1-2 years after the episode (2-year PET)]. The changes in the PET results were evaluated using the dialysate-to-plasma ratio of creatinine (D/PCr) and the dialysate-to-instilled glucose ratio (D4/D0) after a 4-hour dwell. The mean values of D/PCr and D4/D0 showed no statistically significant changes between the initial PETs, 1-year PETs, and 2-year PETs. However, analysis of the results for patients with culture-positive peritonitis (n = 17) revealed significant changes in the mean values of D/PCr and D4/D0 between the initial PET and the 2-year PET (0.63 +/- 0.06 vs 0.70 +/- 0.09, p = 0.01; and 0.41 +/- 0.05 vs 0.37 +/- 0.06, p = 0.04, respectively). The long-term effect of a definite bacterial peritonitis episode seems to be an increase in small-molecule transport. In patients with culture-negative peritonitis, the episode had less impact on peritoneal transport.

Nephrogenic adenoma associated with cytomegalovirus infection of the ureter in a renal transplant patient: presentation as ureteral obstruction

Nephrogenic adenoma (NA), a rare benign lesion of the urinary tract, is widely accepted to be a metaplastic reaction due to urothelial injury. It mainly occurs in the urinary bladder and rarely in the ureter. Renal transplant recipients are prone to the development of NA. However in those patients, NA was diagnosed exclusively in the bladder. Herein, we present the--to our knowledge--first case of NA involving a transplanted ureter. A 42-year-old female kidney transplant recipient suffered hematuria, oliguria, and acute renal failure and presented with ureteral obstruction and hydronephrosis of the renal transplant. To our surprise, evidence of cytomegalovirus (CMV) infection of the NA was demonstrated using special immunohistochemical staining. The findings in this case raise the possibility that CMV infection, as an irritant of the ureteral epithelium, may be an etiological factor of NA.

In vitro migratory responses of swine neutrophils to actinobacillus pleuropneumoniae

Swine neutrophils were quantitatively examined for the direct and indirect migratory responses to Actinobacillus pleuropneumoniae (APP) in vitro and the effects of pseudorabies virus (PrV), frequently co-infecting with APP, were also observed. About 30% of swine neutrophils responded to viable APP, while 3.2% of the neutrophils responded to 0.1% casein which served as the control. The migration of APP was not affected by preincubation of neutrophils with PrV, which inhibited the random migration. When the random migration was normalized to 1, the chemotactic indices for APP, opsonized-APP and casein were 64, 70 and 8.5, respectively. Heat-killed APP or E. coli lipopolysaccharide stimulated the production of interleukin-8 activity by adherent peripheral blood mononuclear cells (PBMC). Preincubation of PBMC with PrV inhibited the production of neutrophil attractant activity when stimulated with heat-killed APP. The results suggested that the direct chemotaxis of neutrophils to viable APP might contribute to early infiltration in Actinobacillus pleuropneumonia, and that PrV might inhibit indirect recruitment of neutrophils to infected lungs by compromising the functions of PBMC.

Common bile duct and pancreatic injury after extracorporeal shock wave lithotripsy for renal stone

Common bile duct and pancreatic injury are rare complications following extracorporeal shock wave lithotripsy. We reported a case of peripancreatic abscess with inflammation change of common bile duct and pancreatic head following extracorporeal shock wave lithotripsy for right renal stone. Its anatomical location and subsequent clinical course suggest it was related to trauma caused by the shock wave. It should be considered a relative contraindication to apply extracorporeal shock wave lithotripsy in cases of right renal stone associated with large gall stones.

Efficacy of surgical treatment in traumatic central cord syndrome

BACKGROUND

Controversy surrounds the treatment of traumatic central cord syndrome (TCCS), as there are strong advocates for nonsurgical treatment for most patients. However, conservative treatment has been shown to yield a longer period of discomfort from pain and weakness in certain cases.

METHODS

In a retrospective review of 114 patients presenting with acute or chronic TCCS from 1988-94, four different age groups were separately observed under different treatments. Motor and sensory recovery were assessed.

RESULTS

Better results were achieved in younger patients, with or without radiographic abnormalities, and in patients with clinically correlated encroaching cord lesions who received early surgical decompression.

CONCLUSIONS

Surgical intervention for TCCS must be addressed with careful clinical and radiographic survey. Removal of offending lesions in the subacute period results in significant motor and sensory improvement in short-term and long-term follow-up.

Early seizures after severe closed head injury

BACKGROUND

We studied the incidence and clinical significance of early post-traumatic seizures after severe closed head injury.

METHODS

This prospective study is based on clinical observation of 3340 adult patients with severe closed head injuries, each of them having a Glasgow Coma Scale (GCS) 3 to 8 after trauma. Anticonvulsant agents were not given to these patients unless there was evidence of seizure.

RESULTS

One hundred and twenty-one patients (3.6%) experienced seizures within 1 week after head injury; 42 of these (1.26% of the series) had seizures within 24 hours after trauma. The incidence of intracerebral parenchymal damage was found to be higher among those patients who developed seizures in the first week (66.1%) than in those who did not (62.7%). However this result did not reach statistical significance. The patients with early seizures had a lower mortality rate (p < 0.01). In patients who survived from the initial injury, the occurrence of early post-traumatic seizures did not appear to influence the neurological recovery at 6 months after injury.

CONCLUSION

Presence of intracerebral parenchymal damage on CT scan after severe closed head injury does not increase the risk of early post-traumatic seizures. With proper treatment, patients presenting with early seizures may have a lower mortality rate. However, the occurrence of early seizures does not influence the neurological recovery in patients who survive the initial severe closed head injury.

C1-C2 fracture-dislocations in children and adolescents

OBJECTIVE

C1-C2 is the predominant level of cervical spine injuries in children and adolescents. Either a fracture of the dens or atlantoaxial dislocation (AAD) without fracture of the dens can occur. We present a number of cases to compare their clinical presentations and discuss the preferred method of treatment.

MATERIAL AND METHODS

There were 12 cases of type II odontoid fracture and 10 cases of AAD without fracture over a 13-year period. There was a male predominance and traffic collisions were the major cause of injury. Two thirds of the dens fractures were in children over 13 years of age and seven out of ten dislocations without fracture were under 13 years of age. Eight patients with fractured dens suffered from spinal cord injuries but six of those with dislocations were neurologically intact. Two patients of fractured dens and one with AAD presented with chronic myelopathies because of undetected injuries.

RESULTS

Three patients expired because of irreversible respiratory failure. Most of the fractured dens achieved bony union after 3 months of halo-vest immobilization but those patients with AAD without fracture usually needed a fusion procedure. Transoral decompression was performed in two cases of dens fracture malunion. All of the survivors of the dens fracture returned to normal or independent daily living. Six of the AAD patients returned to normal, one had a mild neural deficit, and one had persistent spastic quadriparesis.

CONCLUSIONS

There is a higher incidence of atlantoaxial dislocation without fracture in children under 13 years of age and a higher incidence of dens fractures in those over 13 years of age. Those with fractures of the dens are more likely to present with evidence of neural injury while those with AAD are more likely to be neurologically intact; however, a correct diagnosis and proper management are mandatory to prevent chronic myelopathy. Halo-vest immobilization is sufficient for most fractures of the dens in children, with AAD usually requiring a fusion.

Benign osteoblastoma of the spine--report of two cases

Benign osteoblastoma is a rare spinal tumor, with the posterior element mainly involved. Symptoms do vary and there is a long diagnostic delay, especially in young people. We present two cases of benign osteoblastoma. One occurred in the atlas and presented with a painless neck mass. The other occurred in the lumbar spine with symptoms of long-term spinal pain and radicular pain. Preoperative Technetium bone scan and computed tomography (CT) resulted in exact localization and better operative planning. En bloc excision of tumor is indicated for complete pain relief and full return of spinal mobility.

Evasion of host defense by in vivo-produced protoplast-like cells of the insect mycopathogen Beauveria bassiana

In vivo cells (hyphal bodies) of the hyphomycetous insect pathogen Beauveria bassiana collected from host Spodoptera exigua larval hemolymph were osmotically sensitive and lacked a well-defined cell wall. In light and electron microscope studies, a galactose-specific lectin purified from S. exigua hemolymph, concanavalin A (specific for alpha-mannose), and a polyclonal antibody to B. bassiana cell walls all bound to surfaces of in vitro-produced B. bassiana blastospores; however, none of these probes labelled the thin layer of extracellular material covering the plasma membranes of hyphal bodies. These cells were observed freely circulating in S. exigua hemolymph at 36 h postinfection, although immunocompetent hemocytes were known to be present. Additionally, association of hyphal bodies with hemocytes in monolayers was significantly less than for opsonized in vitro blastospores or submerged conidia. The absence of antigenically important galactomannan components on in vivo cells may therefore allow these cells to escape recognition and phagocytosis. Lack of structural components (e.g., chitin, as evidenced by the absence of binding of wheat germ agglutinin) may also be important with respect to evasion of host cellular defense mechanisms. Production of wall material resumed 48 to 60 h postinfection and therefore may coincide with loss of phagocytic capabilities of the hemocytes due to immunosuppressive effects of fungal metabolites. The protoplast-like cells may be formed by the action of hydrolytic enzymes in the hemocytes or by inhibition of fungal cell wall synthetases.

Effect of Beauveria bassiana and Candida albicans on the cellular defense response of Spodoptera exigua

A marked difference in the cellular response of Spodoptera exigua was observed when larvae were challenged with the insect mycopathogen Beauveria bassiana versus the yeast Candida albicans. Both fungi were rapidly phagocytized by circulating hemocytes. The relative growth rate of C. albicans as measured by daughter cell formation was partially suppressed, whereas B. bassiana blastospores produced germ tubes at rates equivalent to those under in vitro conditions. Limited growth by C. albicans within the phagocytic cells stimulated nodulation by hemocytes resulting in the protection of challenged larvae to C. albicans. Alternatively, B. bassiana suppressed the spreading ability of S. exigua hemocytes. These suppressed larvae, while capable of phagocytizing C. albicans, were unable to produce multicellular nodules. Circulating vegetative cells of both C. albicans and B. bassiana were observed to proliferate within these immunosuppressed host larvae.

Bilateral simultaneous transaxillary sympathectomy in treatment of palmar hyperhidrosis: report of 60 cases

Bilateral simultaneous transaxillary sympathectomies (BSTS) were established in order to achieve a one-stage transaxillary sympathectomy in the treatment of palmar hyperhidrosis. The features of the BSTS were the patient's supine operative position, parapectoral incision, and bilateral simultaneous procedures. BSTS were safely performed on 60 patients during a 5-year period. No serious complications or recurrences were encountered. The clinical results suggest that BSTS is the technique of choice for one-stage transaxillary sympathectomy in the treatment of palmar hyperhidrosis.

Bacteriological study in chronic maxillary sinusitis

The bacterial findings of 73 maxillary sinuses in 48 patients with chronic maxillary sinusitis, together with 7 non-inflamed sinuses, are reported. Employing an intraoperative technique and simultaneous collection of 3 different types of specimens in the present investigation made possible comparison of their bacterial characteristics. The results indicated that intraoperative culture of antral mucosa seems to provide the most reliable finding of bacterial flora in chronic maxillary sinusitis. The anaerobic bacteria were never found in the mucosal culture of non-inflamed sinus. The anaerobes appeared to invade the sinus cavity following the sealing of the ostium through the lymphatic or venous system and maintain the inflammatory process. Microbiological analysis of the results between the infected and non-inflamed sinuses established anaerobic bacteria as the most important pathogen in chronic maxillary sinusitis. The predominant anaerobes recovered in descending order of frequency were Veillonella sp., Peptococcus sp., Propionibacterium acne and anaerobic nonspore-forming GPB. Statistical analysis of the results of mucosal culture of inflamed and control materials demonstrated that those aerobic and faculatative bacteria recovered in the inflamed sinus appeared to be the normal inhabitants of non-inflamed sinus mucosa. The presence of normal flora in the normal healthy sinus mucosa may explain the chain of events that follows the occlusion of the ostium. These aerobic bacteria may become pathogenic and play a role in the pathogenesis of sinusitis.