Decoding the genome of bloodsucking midge Forcipomyia taiwana (Diptera: Ceratopogonidae): Insights into odorant receptor expansion

Biting midges, notably those within the Ceratopogonidae family, have long been recognized for their epidemiological significance, both as nuisances and vectors for disease transmission in vertebrates. Despite their impact, genomic insights into these insects, particularly beyond the Culicoides genus, remain limited. In this study, we assembled the Forcipomyia taiwana (Shiraki) genome, comprising 113 scaffolds covering 130.4 Mbps-with the longest scaffold reaching 7.6 Mbps and an N50 value of 2.6 Mbps-marking a pivotal advancement in understanding the genetic architecture of ceratopogonid biting midges. Phylogenomic analyses reveal a shared ancestry between F. taiwana and Culicoides sonorensis Wirth & Jones, dating back approximately 124 million years, and highlight a dynamic history of gene family expansions and contractions within the Ceratopogonidae family. Notably, a substantial expansion of the odorant receptor (OR) gene family was observed, which is crucial for the chemosensory capabilities that govern biting midges' interactions with their environment, including host seeking and oviposition behaviors. The distribution of OR genes across the F. taiwana genome displays notable clusters on scaffolds, indicating localized tandem gene duplication events. Additionally, several collinear regions were identified, hinting at segmental duplications, inversions, and translocations, contributing to the olfactory system's evolutionary complexity. Among the 156 ORs identified in F. taiwana, 134 are biting midge-specific ORs, distributed across three distinct clades, each exhibiting unique motif features that distinguish them from the others. Through weighted gene co-expression network analysis, we correlated distinct gene modules with sex and reproductive status, laying the groundwork for future investigations into the interplay between gene expression and adaptive behaviors in F. taiwana. In conclusion, our study not only highlights the unique olfactory repertoire of ceratopogonid biting midges but also sets the stage for future studies into the genetic underpinnings of their unique biological traits and ecological strategies.

Identification of the chitinase genes from the diamondback moth, Plutella xylostella

Chitinases have an indispensable function in chitin metabolism and are well characterized in numerous insect species. Although the diamondback moth (DBM) Plutella xylostella, which has a high reproductive potential, short generation time, and characteristic adaptation to adverse environments, has become one of the most serious pests of cruciferous plants worldwide, the information on the chitinases of the moth is presently limited. In the present study, using degenerated polymerase chain reaction (PCR) and rapid amplification of cDNA ends-PCR strategies, four chitinase genes of P. xylostella were cloned, and an exhaustive search was conducted for chitinase-like sequences from the P. xylostella genome and transcriptomic database. Based on the domain analysis of the deduced amino acid sequences and the phylogenetic analysis of the catalytic domain sequences, we identified 15 chitinase genes from P. xylostella. Two of the gut-specific chitinases did not cluster with any of the known phylogenetic groups of chitinases and might be in a new group of the chitinase family. Moreover, in our study, group VIII chitinase was not identified. The structures, classifications and expression patterns of the chitinases of P. xylostella were further delineated, and with this information, further investigations on the functions of chitinase genes in DBM could be facilitated.

Dental diagnostic X-ray exposure and risk of benign and malignant brain tumors

BACKGROUND

This study evaluates the risk of benign brain tumors (BBTs) and malignant brain tumors (MBTs) associated with dental diagnostic X-ray, using a large population-based case-control study.

MATERIALS AND METHODS

We identified 4123 BBT cases and 16 492 controls without BBT (study 1) and 197 MBT cases and 788 controls without MBT (study 2) from Taiwan National Health Insurance claim data. The risks of both types of tumor were estimated in association with the frequency of received dental diagnostic X-ray.

RESULTS

The mean ages were ~44.2 years in study 1 and 40.6 years in study 2. Multivariable unconditional logistic regression analysis showed that the risk of BBT increases as the frequency of received dental diagnostic X-ray increases. The BBT odds ratio increased from 1.33 [95% confidence interval (CI) 1.22-1.44] for those with annual mean X-ray examination of less than one to 1.65 (95% CI 1.37-1.98) for those with three or more X-ray examinations, after controlling for comorbidities. No significant association was found between MBTs and dental diagnostic X-ray exposure.

CONCLUSIONS

Exposure to dental diagnostic X-rays in oral and maxillofacial care increases the risk of BBTs, but not MBTs.

Regional cerebral blood flow between primary and concomitant fibromyalgia patients: a possible way to differentiate concomitant fibromyalgia from the primary disease

OBJECTIVES

Technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) has been used to detect abnormal regional cerebral blood flow (rCBF) in women with primary fibromyalgia (FM). The main aim of this study was to investigate the rCBF deficit in concomitant FM patients and compare it with primary FM.

METHODS

An observational study was designed to analyse the SPECT findings in 92 female patients recruited from January 2002 to January 2004. Differences in the rCBF hypoperfusive areas between 49 primary and 29 concomitant FM patients were assessed in different areas of the brain using the chi(2)-test for statistical significance.

RESULTS

Tc-99m ECD brain SPECT in 71 FM patients revealed heterogeneous rCBF in comparison to the homogeneous scan in 14 control patients. The most prominent rCBF hypoperfusive region in both primary and concomitant FM groups was the left temporoparietal area, followed by the thalamus, right temporoparietal, frontal, and basal ganglia areas. Differences in rCBF hypoperfusion in these areas for both FM groups were not significant (all p>0.5).

CONCLUSIONS

Reduced rCBF at cortical regions, in addition to previously reported areas at the thalamus and the subcortical nucleus, in FM patients was demonstrated in this study. The perfusion deficit areas were similar between primary and concomitant FM when the underlying disease activity was quiescent. The feasibility of using this neuroimaging study to differentiate FM from the primary disease, such as rheumatoid arthritis (RA)-associated depression and neuropsychiatric lupus, should be considered.

Fever of Unknown Origin in Taiwan

BACKGROUND

Fever of unknown origin (FUO) is a challenging problem worldwide. There was no prospective study of FUO in the past two decades in Taiwan. A prospective study was conducted.

MATERIALS AND METHODS

The prospective study was undertaken from March 2001 to May 2002. All patients fulfilling the modified criteria for FUO, either admitted, referred or consulted in a medical center in southern Taiwan, were enrolled for analysis.

RESULTS

A total of 94 cases met the criteria of FUO. The final diagnoses of FUO consisted of 54 infectious diseases (57.4%), 8 hematologic/neoplastic (8.5%), 7 noninfectious inflammatory (7.4%), 8 miscellaneous (8.5%) and 17 undiagnosed (18.1%) cases. The single most common cause of FUO was tuberculosis. Some infectious diseases, such as rickettsiosis and melioidosis, were rarely reported in western countries. Three patients with hemophagocytotic syndrome without ascertainable etiologies were present with FUO in this study. Between the patients with and those without a final diagnosis, the short-term survival (3 months) was compared by the Kaplan-Meier analysis, which revealed no difference.

CONCLUSIONS

Mycobacteriosis is still the leading cause of FUO in Taiwan and it is important to identify this treatable disease from all causes of FUO. This study has showed geographical variation among the studies of FUO.

Adjoint acceleration of Monte Carlo simulations using TORT/MCNP coupling approach: a case study on the shielding improvement for the cyclotron room of the Buddhist Tzu Chi General Hospital

Full-scale Monte Carlo simulations of the cyclotron room of the Buddhist Tzu Chi General Hospital were carried out to improve the original inadequate maze design. Variance reduction techniques are indispensable in this study to facilitate the simulations for testing a variety of configurations of shielding modification. The TORT/MCNP manual coupling approach based on the Consistent Adjoint Driven Importance Sampling (CADIS) methodology has been used throughout this study. The CADIS utilises the source and transport biasing in a consistent manner. With this method, the computational efficiency was increased significantly by more than two orders of magnitude and the statistical convergence was also improved compared to the unbiased Monte Carlo run. This paper describes the shielding problem encountered, the procedure for coupling the TORT and MCNP codes to accelerate the calculations and the calculation results for the original and improved shielding designs. In order to verify the calculation results and seek additional accelerations, sensitivity studies on the space-dependent and energy-dependent parameters were also conducted.

Usefulness of 99mTc ethyl cysteinate dimer brain SPECT to detect abnormal regional cerebral blood flow in patients with acute carbon monoxide poisoning

99mTc ethyl cysteinate dimer (99mTc-ECD) brain single photon emission computed tomography (SPECT) was used to detect abnormal regional cerebral blood flow (rCBF) in patients with acute carbon monoxide (CO) poisoning. Ten patients with acute CO poisoning and no past histories of psychoneurological disorders were enrolled in this study. After oxygen treatment, all of the 10 patients were investigated using 99mTc-ECD brain SPECT and brain computed tomography (CT) scan. Brain CT scan findings were normal in all of the 10 patients. 99mTc-ECD brain SPECT showed the hypoperfusion lesions of the basal ganglia and brain cortex in five and seven patients, respectively. Only three of the 10 patients had normal 99mTc-ECD brain SPECT findings. This study suggests that, in comparison with brain CT scan, 99mTc-ECD brain SPECT is a better tool for the early detection of hypoperfusion brain lesions in acute CO poisoning in patients with normal brain CT findings.

The refined shielding design for the cyclotron room of the Buddhist Tzu Chi General Hospital

Full-scale Monte Carlo simulations of the cyclotron room of the Buddhist Tzu Chi General Hospital were carried out to improve the inadequate maze design. The double differential neutron source from the 18O(p,n)18F reaction was adopted for the calculation. The weight window variance reduction technique, where the weight window was set by applying the adjoint flux, has been implemented in the MCNP run to facilitate the calculation of the dose rates outside the cyclotron room. Dose rates including neutron and gamma-ray components were calculated for some maze shielding modifications.

Usefulness of thallium-201 muscle scan to investigate perfusion reserve in the lower limbs of patients with systemic lupus erythematusus

Patients with systemic lupus erythematosus (SLE) may develop premature atherosclerosis, notably peripheral vascular disease presenting with intermittent claudication or gangrene. This study evaluates the usefulness of thallium-201 muscle perfusion scan (Tl-201 muscle scan) for investigating perfusion reserve in the lower limbs of 25 asymptomatic, female SLE patients without peripheral ischemia findings. The patients showed no evidence of peripheral arterial disease in history, physical examination, or Doppler ultrasonography. A control group consisted of 24 healthy, age-matched women. Each subject flexed her right foot maximally both dorsally and plantarly 60 times. In the middle of this exercise, 2 mCi of Tl-201 was injected intravenously. Three minutes after the injection, a posterior image of both calves was obtained using a gamma camera. Rectangular regions of interest were symmetrically drawn over both calves. The total count in the resting calf was subtracted from the total count in the exercising calf, and the percentage of increase, termed the perfusion reserve, was determined. A significant difference was found between the perfusion reserves of the SLE patients and control groups (75.3+/-8.9% and 99.6+/-9.0%, respectively, P <0.05). In conclusion, perfusion reserve in the lower limb muscles of SLE patients may be measured by Tl-201 muscle perfusion scan.

Simultaneously evaluating the effects of one-week fluticasone propionate inhalation therapy on lung ventilation and permeability in children with asthma

This study evaluated the effects of fluticasone propionate inhalation therapy on lung ventilation and alveolar permeability by quantitative Tc-99m DTPA radioaerosol inhalation lung scintigraphy in 15 children with asthma. Lung ventilation was evaluated as the distribution percentage (D%) of Tc-99m DTPA radioaerosols in the central, intermediate and peripheral regions of the right lung. Alveolar permeability was measured by the rate of Tc-99m DTPA radioaerosol clearance curve from the peripheral alveoli of the right lung and represented as slope. The D% and slopes were calculated before and after one-week inhalation therapy (100 microg fluticasone propionate two times daily for one-week) to evaluate the effects of inhalation therapy on lung ventilation and alveolar permeability. The preliminary results revealed statistically significantly improved lung ventilation but no significant change of alveolar permeability in the right lung after one-week fluticasone propionate inhalation therapy in children with asthma. We suggest that the widely available and noninvasive Tc-99m DTPA radioaerosol inhalation lung scintigraphy can simultaneously evaluate lung ventilation and alveolar permeability in one study and should contribute to any disorder involving both alveoli and airways.

Evaluation of alveolar permeability and lung ventilation in patients with chronic renal failure using Tc-99m DTPA radioaerosol inhalation lung scintigraphy

Lung ventilation (LV) and alveolar permeability (AP) were measured in 24 male chronic renal failure (CRF) patients on regular hemodialysis (HD). LV and AP were determined by Tc-99m DTPA aerosol inhalation lung scintigraphy using commercial lung radioaerosol delivery units. The equilibrium LV images were visually interpreted by two independent and experienced nuclear medicine physicians. The degree of AP damage to the total right lung was presented as the clearance rate (k value; %/min) of the time-activity curve from dynamic total right lung images. The results showed 10/24 (42%) cases with inhomogeneous distribution and 8/24 (33%) cases with hypoventilation on equilibrium LV images. In comparison with 10 male normal controls, the k value of the CRF patient group was larger (1.14 +/- 0.36%/min vs 0.75 +/- 0.14%/min, p value < 0.05). In addition, there was no significant correlation for k value and albumin level (r2 = 0.008) or for k value and HD duration (r2 = 0.228). In conclusion, CRF can predispose patients to LV change and AP damage. However, the degree of AP damage is not related to serum albumin level or HD duration.

Evaluation of the effects of methylprednisolone pulse therapy in patients with systemic lupus erythematosus with brain involvement by Tc-99m HMPAO brain SPECT

Methylprednisolone pulse therapy (MPT) was introduced to avoid life-threatening complications in patients with systemic lupus erythematosus (SLE) with brain manifestations; however, the efficacy of MPT in SLE patients with brain involvement is still uncertain and needs to be objectively evaluated. We enrolled 15 female SLE patients with neuropsychiatric manifestations in this study. All patients had normal brain MRI and abnormal brain HMPAO-SPECT findings. Follow-up HMPAO-SPECT studies were conducted 2 weeks after MPT. Serum levels of anticardiolipin antibodies (ACA) and anti-ribosomal P antibodies (anti-P) were measured before and after MPT. Before MPT, 7 patients were positive for ACA and 7 patients were positive for anti-P. After MPT, none of the 15 patients demonstrated positive serologic findings or neuropsychiatric manifestations. Based on the follow up brain HMPAO-SPECT images following MPT, 13 patients showed disappearance of the perfusion defects and 2 patients showed partial recovery of rCBF. Brain HMPAO-SPECT imaging is a logical and objective tool for measuring the effects of MPT in SLE patients with brain involvement by determining of changes in rCBF.

Using 99mTc HMPAO brain SPECT to evaluate the effects of anticoagulant therapy on regional cerebral blood flow in primary antiphospholipid antibody syndrome patients with brain involvement-a preliminary report

Technetium-99m hexamethylpropylene amine oxime ((99m)Tc HMPAO) brain single photon emission computed tomography (SPECT) was used to evaluate the effects of anticoagulant therapy (ACT) on regional cerebral blood flow (rCBF) in patients with primary antiphospholipid antibody syndrome (PAPS). Sixteen female PAPS patients with neuropsychiatric manifestations and hypoperfusion lesions demonstrated on initial (99m)Tc HMPAO brain SPECT images were enrolled in this study. Follow-up (99m)Tc HMPAO brain SPECT images were performed 1 month after ACT. Meanwhile, serum anticardiolipin antibodies (ACA) were measured before and after ACT. Before ACT, 14 (87.5%) patients had positive ACA. After ACT, all 16 PAPS patients showed decreased serologic findings, and their neuropsychiatric manifestations subsided. After ACT, 11 (68.8%) patients showed complete recovery of regional cerebral blood flow (rCBF) and five (31.2%) patients showed partial recovery in the follow-up (99m)Tc HMPAO brain SPECT images. This type of imaging is a logical and objective tool for measuring the effects of ACT in PAPS patients with brain involvement by determining changes in rCBF.

Usefulness of technetium-99m methoxyisobutylisonitrile liver single photon emission computed tomography to detect hepatocellular carcinoma

Technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI) has been shown to be useful in identifying several types of tumors, such as breast, lung and thyroid cancers. The usefulness of Tc-99m MIBI liver imaging in detecting hepatocellular carcinoma (HCC) is still controversial. In this study, 22 patients with HCC performed Tc-99m MIBI liver single photon emission computed tomography (SPECT). Twenty of 22 patients (90.9%) showed negative liver SPECT findings without significant Tc-99m MIBI uptake in HCC, and only 2 patients (9.1%) showed positive liver SPECT findings with significant Tc-99m MIBI uptake in HCC. In addition, no significant correlation between liver SPECT findings with sex, age, alpha feto-protein serum level, HCC differentiation, and virus hepatitis status was found. We concluded that Tc-99m MIBI liver SPECT is not a sensitive tool to detect HCC.

Usefulness of Tc-99m ECD brain SPECT to evaluate the effects of methylprednisolone pulse therapy in lupus erythematosus with brain involvement: a preliminary report

Methylprednisolone pulse therapy (MPT) was introduced to avoid life-threatening complications in systemic lupus erythematosus (SLE) with brain manifestations. However, its efficacy in SLE patients remains uncertain and needs to be objectively evaluated. In this study, technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) was used to detect regional cerebral blood flow (rCBF) in SLE patients with normal brain magnetic resonance imaging (MRI) findings. Twelve female SLE patients with neuropsychiatric symptoms were enrolled in this study. All patients had normal brain MRI and abnormal Tc-99m ECD brain SPECT findings. The Tc-99m ECD brain SPECT studies were performed 2 weeks after MPT. Pre- and post-MPT serum levels of anticardiolipin antibodies (ACA) and antiribosomal P antibodies (anti-P) were also measured. Before MPT, four patients had positive ACA and seven had positive anti-P. After MPT, all 12 patients demonstrated negative serologic findings and no neuropsychiatric symptoms. After MPT, ten patients showed complete recovery and two showed partial recovery of rCBF in the follow-up Tc-99m ECD brain SPECT images. This imaging is a logical and objective tool for measuring the effects of MPT in SLE patients with brain involvement by the determination of rCBF changes.

Usefulness of whole body positron emission tomography (PET) with 18F-fluoro-2-deoxyglucose (FDG) to detect recurrent ovarian cancer based on asymptomatically elevated serum levels of tumor marker

The aim of this study was to evaluate practice usefulness of whole body positron emission tomography (PET) with 18F-fluoro-2-deoxyglucose (FDG) to detect recurrent ovarian cancer based on asymptomatically elevated tumor marker (CA-125) serum levels. Whole-body FDG-PET was performed in 28 patients with suspected recurrent ovarian cancers and asymptomatically increased serum levels of tumor marker (CA-125 antigen) but negative or equivocal other imaging modality results. All of these 28 asymptomatic patients had serum levels of CA-125 antigen >35 U/ml. The final diagnosis of recurrent ovarian cancer was established by operation/biopsy histopathological findings or clinical follow-up longer than 1 year by additional morphologic imaging techniques. Among the 28 patients, the final diagnoses of recurrent ovarian cancers and benign lesions were established in 20 and 8 patients, respectively. FDG-PET accurately diagnosed recurrent ovarian cancers in 19 patients and benign lesions in 7 patients. When asymptomatically elevated serum levels of CA-125 antigen, the diagnostic sensitivity, specificity, and accuracy of FDG-PET to detect recurrent ovarian cancers were 95.0%, 87.5%, and 92.9%, respectively. FDG-PET is a useful technique to detect recurrent ovarian cancers for patients suspected of recurrent ovarian cancers due to asymptomatically elevated serum levels of CA-125 antigen.

Early predicting recurrent cervical cancer with combination of tissue polypeptide specific antigen (TPS) and squamous cell carcinoma antigen (SCC)

The establishment of new tumor marker combinations including strong lead-time effects in detecting recurrent cervical cancer appears to be warranted. This retrospective study includes 50 patients with recurrent squamous cell cervical cancer after operation or radiotherapy. The serial serum levels of the tumor markers tissue polypeptide specific antigen (TPS) and squamous cell carcinoma antigen (SCC) were determined. Cutoff values of 78.5 U/L for TPS and 1.5 microg/L for SCC were selected according to the 95th percentile of serum concentrations measured in healthy control patients. Comparing with other monitoring modalities, SCC and TPS showed lead-time effective in 27 and 30 cases, respectively. This difference was not statistically significant. The combination of SCC and TPS provided lead-time effects in 42 cases. Our data indicate that combination of TPS and SCC is a valuable tool in the early predicting recurrent cervical cancer.

Comparing whole body 18F-2-deoxyglucose positron emission tomography and technetium-99m methylene diophosphate bone scan to detect bone metastases in patients with non-small cell lung cancer

Despite advances in morphological imaging, some patients with non-small cell lung cancer (NSCLC) are found to have non-resectable disease at surgery or die of recurrence within a year of surgery. At present, metastatic bone involvement is usually assessed using conventional technetium-99m methylene diophosphate (Tc-99m MDP) whole body bone scan (bone scan), which has a high sensitivity but a poor specificity. We have attempted to evaluate the usefulness of whole body positron emission tomography with 18F-2-deoxyglucose (FDG-PET) for the detection of malignant bone metastases of NSCLC, and to compare FDG-PET results with Bone Scan findings. Forty-eight patients with biopsy-proven NSCLC and suspected to have stage IV disease underwent whole body bone scan and FDG-PET to detect bone metastases. The final diagnoses of bone metastases were established by operative, histopathological findings or clinical follow-up longer than 1 year by additional radiographs or following FDG-PET/Tc-99m MDP bone scan findings showing progressively and extensively widespread bone lesions. A total of 138 bone lesions found on either FDG-PET or Tc-99m MDP bone scan were evaluated. Among the 106 metastatic and 32 benign bone lesions, FDG-PET and Tc-99m MDP bone scan could accurately diagnose 99 and 98, as well as 30 and 2 metastatic and benign bone lesions, respectively. Diagnostic sensitivity and accuracy of FDG-PET and Tc-99m MDP bone scan were 93.4% and 92.5%, as well as 93.5% and 72.5%, respectively. In conclusion, our data suggest that FDG-PET with the same sensitivity and a better accuracy than those of Tc-99m MDP bone scan to detect metastatic bone lesions in patients with biopsy-proven NSCLC and suspected to have stage IV disease.

Detection of cervical lymph node metastases in nasopharyngeal carcinomas: comparison between technetium-99m methoxyisobutylisonitrile single photon emission computed tomography and magnetic resonance imaging

We compared the effectiveness technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI) single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) of head and neck in evaluating cervical lymph node (LN) metastasis in nasopharyngeal carcinomas (NPC). Forty NPC patients with cervical LN metastases confirmed histopathologically underwent Te-99m MIBI SPECT and MRI of the head and neck to evaluate cervical LN metastases. For 16 LN lesions with discordant results between Tc-99m MIBI SPECT and MRI, Tc-99m MIBI SPECT could correctly detect 1 metastatic and 10 benign LN lesions as well as MRI could correctly detect 3 metastatic and 2 benign LN lesions. Agreement positive results of Tc-99m MIBI SPECT and MRI could correctly detect all of the remaining 24 metastatic LN lesions. Tc-99m MIBI SPECT has a better specificity but a lower sensitivity for detecting cervical LN metastases in NPC when compared with MRI. The combined use of Tc-99m MIBI SPECT and MRI could increase the accuracy compared with the single use of either Te-99m MIBI SPECT or MRI to detect cervical LN metastases in NPC.

Comparing whole body 18F-2-deoxyglucose positron emission tomography and technetium-99m methylene diphosphate bone scan to detect bone metastases in patients with renal cell carcinomas - a preliminary report

PURPOSE

Conventional technetium-99m methylene diphosphate whole body bone scan (bone scan) has a high sensitivity but a poor specificity to detect bone metastases. However, positron emission tomography with 18F-2-deoxyglucose (FDG-PET) can offer superior spatial resolution and improved specificity. We have attempted to evaluate the usefulness of FDG-PET for detecting bone metastases in renal cell carcinomas (RCC) and to compare FDG-PET results with bone scan findings.

METHODS

Eighteen patients were selected for this study with biopsy-proven RCC. They were suspected of having bone metastases and were undergoing bone scan and FDG-PET to detect bone metastases. The final diagnoses of bone metastases were established by operative, histopathological findings or clinical follow-up longer than 1 year by additional radiographs or following FDG-PET/bone scan findings showing progressive and extensive widespread bone lesions.

RESULTS

A total of 52 bone lesions including 40 metastatic and 12 benign bone lesions found on either FDG-PET or bone scan were evaluated. FDG-PET could accurately diagnose all 40 metastatic and 12 benign bone lesions. Bone scan could accurately diagnose only 31 metastatic bone lesions. Diagnostic sensitivity and accuracy of FDG-PET were 100% and 100%, respectively,and bone scan were 77.5% and 59.6%, respectively.

CONCLUSIONS

Our data suggest that FDG-PET has a higher sensitivity and a better accuracy than that of bone scan to detect bone metastases in patients with RCC.

Comparing whole body (18)F-2-deoxyglucose positron emission tomography and technetium-99m methylene diphosphonate bone scan to detect bone metastases in patients with breast cancer

PURPOSE

At present, bone metastases are usually assessed using conventional technetium-99m methylene diphosphonate whole-body bone scan, which has a high sensitivity but a poor specificity. However, positron emission tomography with (18)F-2-deoxyglucose (FDG-PET) can offer superior spatial resolution and improved specificity. We attempted to evaluate the usefulness of FDG-PET for detecting bone metastases in breast cancer and to compare FDG-PET results with bone scan findings.

PATIENTS

The study group comprised 48 patients with biopsy-proven breast cancer and suspected of having bone metastases who underwent bone scan and FDG-PET to detect the bone metastases. The final diagnosis of bone metastases was established by operative, histopathological findings or during a clinical follow-up longer than 1 year by additional radiographs or following FDG-PET/bone scan findings showing progressive widespread bone lesions.

RESULTS

A total of 127 bone lesions including 105 metastatic and 22 benign bone lesions found by either FDG-PET or bone scan were evaluated. Using FDG-PET, 100 metastatic and 20 benign bone lesions were accurately diagnosed, and using bone scan 98 metastatic and 2 benign bone lesions were accurately diagnosed. The diagnostic sensitivity and accuracy of FDG-PET were 95.2% and 94.5%, and of bone scan were 93.3% and 78.7%, respectively.

CONCLUSIONS

Our findings suggest that FDG-PET shows a similar sensitivity and a better accuracy than bone scan for detecting bone metastases in patients with breast cancer.

Detection of recurrent nasopharyngeal carcinomas with positron emission tomography using 18-fluoro-2-deoxyglucose in patients with indeterminate magnetic resonance imaging findings after radiotherapy

PURPOSE

The aim of this study was to evaluate the effectiveness of positron emission tomography (PET) using 18-fluoro-2-deoxyglucose (FDG) to detect recurrent nasopharyngeal carcinomas (NPC) when magnetic resonance imaging (MRI) findings are indeterminate.

PATIENTS AND METHODS

After radiotherapy, 28 NPC patients with indeterminate MRI findings were included. MRI, FDG-PET, and biopsy were performed at least 4 months after radiotherapy and within 1 week. The final results were based on histopathologic findings and a clinical follow-up of at least 6 months.

RESULTS

For detecting recurrent NPC in indeterminate MRI findings, the sensitivity, specificity and accuracy of FDG-PET were 100.0%, 92.9% and 96.4%, respectively.

CONCLUSIONS

Based on these results, we can recommend FDG-PET for detecting recurrent NPC when MRI findings are indeterminate.

Technetium-99m tetrofosmin chest imaging related to p-glycoprotein expression for predicting the response with paclitaxel-based chemotherapy for non-small cell lung cancer

Our aim was to use technetium-99m tetrofosmin (Tc-TF) uptake in non-small cell lung cancer (NSCLC) for predicting the chemotherapeutic response of NSCLC to paclitaxel and to compare the results with the expression of multidrug resistance (MDR) - P-glycoprotein (Pgp). Twenty patients with advanced NSCLC were enrolled in this study before chemotherapy with paclitaxel. Tc-TF chest imaging was performed to calculate early and delayed tumor-to-normal lung (T/NL) count-density ratios, as well as washout indexes (WIs). Immunohistochemical analyses were performed on multiple nonconsecutive sections of the biopsy specimens to detect Pgp expression. The response to chemotherapy was evaluated by clinical and radiological methods in the third month after completion of treatment. The early and delayed T/NL count-density ratios of patients with good response were significantly higher than those of patients with poor response (p <0.05). However, no significant difference in WI between the two groups of patients was found (p > 0.05). A significantly higher incidence of good response was found in patients with negative Pgp expression (100%) than in patients with positive Pgp expression (40%) (p <0.05). Significantly higher early and delayed T/NL count-density ratios as well as decreased WIs were found in patients with negative Pgp expression than in patients with positive Pgp expression. However, other prognostic factors (age, sex, body weight loss, performance status, tumor stage, and tumor cell type) were not significantly different between the patients with good response and those with poor response. Because Tc-TF chest images can correctly represent the expression of Pgp in NSCLC, it can accurately predict the chemotherapeutic response to paclitaxel.

Detection of esophageal carcinoma using single-photon emission computed tomography of thallium-201: a preliminary report

The aim of this preliminary study was to evaluate the potential usefulness of thallium-201 (Tl-201) in detecting esophageal carcinoma. A total of 15 patients with esophageal carcinoma were arranged for Tl-201 single-photon emission computed tomography (SPECT) of the chest. Thirteen of the patients had epidermoid carcinoma and two had adenocarcinoma. Meanwhile, 7 normal controls without any history of esophageal disease also accepted Tl-201 SPECT of the chest for comparison. From the 15 patients, Tl-201 chest SPECT detected esophageal carcinoma in 13 (86.7%) but not in 2 (13.3%) patients with epidermoid carcinoma. In contrast, all 7 normal controls (100.0%) had negative results of Tl-201 chest SPECT. Our study showed that the Tl-201 chest SPECT scan could be considered as a non-invasive useful imaging method in detection of esophageal carcinoma.

Differentiating benign and malignant pulmonary lesions with FDG-PET

The purpose of this retrospective study was to evaluate the efficacy of positron emission tomography (PET) with 18F-fluoro-2-deoxyglucose (FDG) to differentiate benign from malignant pulmonary lesions. Fifty-five patients, suspected of having primary pulmonary neoplasm based on chest radiographic findings, underwent FDG-PET scanning. Pathological diagnoses were obtained in 41 patients with a total of 43 pulmonary lesions. The other 14 patients (14 lesions) were followed-up clinically for at least four months. The standard uptake value (SUV) was determined in each patient. The SUV of the 15 benign and 40 malignant pulmonary lesions were 1.60+/-0.42 and 6.14+/-2.67, respectively. If SUV was > 2.50, the pulmonary lesion was considered as a malignant pulmonary lesion. FDG-PET could correctly detect 34 true-positive and 15 true-negative pulmonary lesions. However, 6 false-positive and one-false negative pulmonary lesions were misdiagnosed by FDG-PET. The sensitivity, specificity and accuracy of FDG-PET to differentiate between benign and malignant pulmonary lesions were 94%, 71% and 86%, respectively. FDG-PET can accurately detect malignant pulmonary lesions with a high sensitivity. However, false-positive FDG-PET findings caused by some inflammatory processes may decrease its specificity.

Comparison of the uptake and clearance of Tc-99m MIBI, Tl-201 and Ga-67 in drug-resistant lymphoma cell lines

Tc-99m sestamibi (MIBI) has been used as a tumor-seeking agent. However, its role in detecting lymphomas has not been widely investigated. The aim of the present study was to determine the uptake and clearance characteristics of Tc-99m MIBI in vincristine-resistant lymphoma cell lines. In addition, thallium-201 (Tl-201) and gallium-67 (Ga-67) uptake and clearance characteristics were evaluated for comparison with Tc-99m MIBI. Drug-resistant lymphoma cell lines (monocyte-like, histiocytic lymphoma, human; B-lymphoma cell line, American Burkitt lymphoma, lymphoblastoid, human; Hodgkin's disease, lymphoid, human) were selected by multistep vincristine treatment up to 50 nM. After incubation of the radiotracers, Tc-99m MIBI, Tl-201 and Ga-67, in medium for 0, 10, 20, 30, 60 or 120 min, the uptake and clearance of each radiotracer were measured in the drug-resistant lymphoma cell lines. In addition, P-glycoprotein expression was determined by immunohistochemical study. In a comparison of the three radiotracers, the uptake of Tc-99m MIBI was the greatest in the studied wild-type lymphoma cell lines. Tc-99m MIBI uptake was much lower in drug-resistant tumor cell lines than in non-resistant cell lines. On the other hand, the uptake characteristics of Tl-201 did not differ between drug-resistant and non-resistant cells. Immunohistochemistry analyses of Ab-1 or JSB indicated that tumor cells expressed MDR-1 protein in all three cell lines. Tc-99m MIBI is a good radiotracer for detecting drug resistance in lymphoma cell lines.

Predicting chemotherapy response and comparing with P-glycoprotein expression using technetium-99m tetrofosmin scan in untreated malignant lymphomas

The purposes of this study were to predict the chemotherapy response of untreated malignant lymphomas (ML) using a technetium-99m tetrofosmin (Tc-TF) scan and to compare Tc-TF results with P-glycoprotein (Pgp) expression. Before undergoing chemotherapy, 25 patients with ML were enrolled in this study. Tc-TF scan was performed 10 min after intravenous injection of Tc-TF. Immunohistochemical analyses were performed on multiple sections of ML specimens to evaluate Pgp expression. The chemotherapy response was evaluated in the first 1-2 years after the completion of treatment. The mean tumor-to-background ratio of the 15 patients with good responses (3.23+/-0.56) was significantly higher than that of the ten patients with poor responses (1.18+/-0.11). All of the 15 patients with good responses had positive Tc-TF scan results, but negative Pgp expression. Among the ten patients with poor responses, all had negative Tc-TF scan results, but six had positive Pgp expression and four had negative Pgp expression. Significant differences in the incidences of good and poor responses were found between patients with positive Tc-TF scan results and patients with negative Tc-TF scan results and between patients with positive Pgp expression and patients with negative Pgp expression. No significant differences in the incidences of good and poor responses were found between Hodgkin's disease patients and non-Hodgkin's lymphoma patients, stage I-II patients and III-IV patients, patients aged >40 and patients aged < or =40 years, and patients with and without B symptoms. Compared with other prognostic factors, Tc-TF scan results and Pgp expression more accurately predict the chemotherapy response in patients with ML.

The role of 18F-fluorodeoxyglucose positron emission tomography in cancer screening - a preliminary report

Positron emission tomography (PET) with 18F-fluoro-2 deoxy-D-glucose (FDG) is a non-invasive method for surveying the whole body and detecting various malignancy. A total of 299 subjects underwent whole-body FDG PET studies in our PET center over an 18-month period. FDG PET accurately detected malignant tumors in 7 (2.34%) subjects. False positive FDG PET studies in 3 (1%) subjects and false negative FDG PET studies in 2 (0.6%) subjects were found. Because of the high cost of FDG PET examination, it might not be suitable as a cancer screening test for the general population. However, it is a valuable supplemented tool for routine check-up, particularly for those at high-risk of developing cancer.

Comparison of technetium-99m tetrofosmin and gallium-67 citrate scintigraphy for detecting malignant lymphoma

The aim of this study was to compare the value of technetium-99m tetrofosmin (Tc-TF) scintigraphy with that of gallium-67 citrate (Ga-67) scintigraphy for detecting malignant lymphoma. In this study, 50 patients with malignant lymphoma underwent Tc-TF and Ga-67 scintigraphy before receiving any therapy. Tc-TF scintigraphy detected malignant lymphoma in 44 (88%) patients, but was false-negative in 4 cases of infradiaphragmatic malignant lymphoma and in 2 cases of malignant lymphoma with chemotherapy resistance. Ga-67 scintigraphy detected malignant lymphoma in 45 (90%) patients, but was false-negative in 3 cases of low-grade non-Hodgkin's lymphoma and in 2 cases of malignant lymphoma with bone marrow involvement. There was no significant difference in sensitivity between Tc-TF and Ga scintigraphy. However, a combination of Tc-TF and Ga-67 scintigraphy detected malignant lymphoma in all 50 patients (100%). We conclude that it is necessary to combine Tc-TF and Ga-67 scintigraphy to accurately detect malignant lymphoma.

To predict chemotherapy response using technetium-99m tetrofosmin and compare with p-glycoprotein and multidrug resistance related protein-1 expression in patients with untreated small cell lung cancer

The aim of this study was to investigate the relationships among technetium-99m tetrofosmin (Tc-TF) accumulation in untreated small cell lung cancer (SCLC), the expression of P-glycoprotein (Pgp) and multidrug resistance related protein-1 (MRP1), and the response to chemotherapy in patients with untreated SCLC. Thirty patients with SCLC were studied with chest scintigraphy 15 to 30 min after intravenous injection of Tc-TF before chemotherapeutic induction. Tc-TF chest scans were interpreted both visually and quantitatively. The response to chemotherapy was evaluated upon completion of chemotherapy. Immunohistochemical analyses were performed on multiple non-consecutive sections of biopsy specimens to detect Pgp and MRP1 expression. Fifteen patients with good response to chemotherapy had a significantly higher incidence (100.0%) of positive Tc-TF chest single photon emission computed tomography (SPECT) findings and negative Pgp or MPR expression than 15 patients with poor response (20%) (P<0.05). The tumor/background (T/B) ratios were 1.8+/-0.3 and 1.2+/-0.3 for patients with good response and poor response, respectively (P<0.05). However, other prognostic factors (performance status, tumor size and stage) were not significantly related to Tc-TF chest scan findings and response to chemotherapy. Tc-TF chest scintigraphy correlated well with Pgp or MRP1 expression and accurately predicted the response to chemotherapy in patients with SCLC.

Changes in the levels of nitric oxide synthase and protein kinase C gamma following kainic acid receptor activation in the rat spinal cord

In this study, we evaluated the levels of nitric oxide synthase, both neuronal and induced (nNOS and iNOS, respectively), cyclooxygenase-1 and 2 (COX-1 and COX-2) and protein kinase C gamma (PKCgamma) and correlated these with algogenic behavior following spinal kainic acid (KA) receptor activation in rats. Thirty adult male Sprague-Dawley rats were randomly assigned into six groups (n=5). Groups A, B, and C received 0.5 g kainic acid intrathecally and were analyzed at 3, 6, 24 h after injection, respectively. Groups D, E, and F received saline and were analyzed at 3, 6, 24 h after injection, respectively. We observed for behavioral changes in the rats following intrathecal KA injection and analyzed the protein levels of NOS, COX and PKCgamma by Western blotting techniques. Importantly, we clarified the potential roles of PKCgamma in the regulation of nNOS and COX-2 following intrathecal injection with KA in the rat spinal cord. COX-2 protein was detected but not significantly changed in the lumbosacral spinal cord at 3, 6, and 24 h following intrathecal KA injection (P>0.05). In contrast, nNOS protein was detected at higher levels in comparison with normal spinal cord at 6 and 24 h after intrathecal administration of KA (P<0.05). PKCgamma also increased significantly at 3, 6, and 24 h after intrathecal KA injection when compared with the baseline level (P<0.05). On the other hand, COX-1 and iNOS were not detected in either normal or KA treated spinal cords. These results provide strong in vivo evidence to support the idea that nNOS but not COX-2, plays an important role in spinal KA receptor activation. Furthermore, up-regulation of PKCgamma is involved in KA induced algogenic behavior in rats.

The higher likelihood of developing cardiomegaly during follow-up in patients with syndrome X and abnormal thallium-201 myocardial perfusion SPECT

'Syndrome X' describes patients with exertional chest pain and a normal coronary arteriogram. In some patients, acute myocardial ischemia can be demonstrated by regional myocardial perfusion defects on thallium-201 exercise test. However, some patients with typical angina have normal perfusion on thallium-201 heart scintigraphy. It is not clear whether there are different prognoses for patients with normal and abnormal thallium studies. In this study, the clinical features, long term follow-up and clinical results of syndrome X patients with normal and abnormal thallium studies were evaluated to determine the differences between these two groups. Fifty-nine patients (52 males, seven females, mean age 62+/-6 years) with syndrome X were enrolled and divided into two groups on the basis of results of thallium-201 heart scintigraphy. Group I was comprised of 22 patients with normal thallium-201 perfusion scan and group II was comprised of 37 patients with abnormal thallium-201 heart scan. All subjects received coronary arteriography, exercise test, thallium-201 myocardial SPECT, ejection fraction of left ventricle, echocardiography, blood analysis and long term follow-up with questionnaire for 10 years. Lower maximal rate-pressure product and higher angina scores were found in group II. More patients developed cardiomegaly (nine of 33 patients) in group II than in group I (one of 21 patients). Both groups, however, were at low risk for cardiac events (cardiac death or myocardial infarction).

Comparison of CYFRA 21-1 and squamous cell carcinoma antigen in detecting nasopharyngeal carcinoma

CYFRA 21-1 is a newly developed tumor marker that is especially useful for detecting squamous cell carcinoma (SCC) of the lung. Squamous cell carcinoma antigen is a proven tumor marker that is especially useful for detecting SCC of the cervix. Our aim in this study was to compare the clinical value of CYFRA 21-1 and SCC antigen in the detection of nasopharyngeal carcinoma (NPC). Serum levels of CYFRA 21-1 and SCC antigen were measured in 80 untreated NPC patients and 77 healthy controls. The cutoff values of CYFRA 21-1 and SCC antigen, determined at the 95th percentile of the 77 healthy controls, were 2.48 ng/mL and 1.49 ng/mL, respectively. The results revealed that the mean serum value of only CYFRA 21-1 was significantly higher in the 80 NPC patients than in the 77 healthy controls, and the detection sensitivity of CYFRA 21-1 for NPC was significantly higher than that of SCC antigen. In conclusion, our results suggest that CYFRA 21-1 is a better tumor marker than SCC antigen for detection of NPC.

Evaluation of chemotherapy response using technetium-99M-sestamibi scintigraphy in untreated adult malignant lymphomas and comparison with other prognosis factors: a preliminary report

The purpose of this study was to predict chemotherapy response using technetium-99m methoxyisobutylisonitrile (Tc-MIBI) scintigraphy in untreated adult malignant lymphomas (ML) and compare the response with other prognosis factors. Before chemotherapy, 25 adult patients with ML were enrolled in this study. Tc-MIBI scintigraphy was performed 10 min after intravenous injection of Tc-MIBI to calculate tumor-to-background (T/B) uptake ratio and interpret the results visually. Chemotherapy response was evaluated in the first 1 to 2 years after completion of treatment by clinical and radiological methods. The mean T/B uptake ratio of the 15 patients with good response (3.3 +/- 0.6) was significantly higher than that of the 10 patients with poor response (1.2 +/- 0.1). All of the 15 patients with good response had positive Tc-MIBI scintigraphic results. All of the 10 patients with poor response had negative Tc-MIBI scintigraphic results. However, there were no significant differences in the incidences of good and poor responses for other prognosis factors. In our preliminary study, when compared with other prognosis factors, Tc-MIBI scintigraphy was the best tool to predict chemotherapy response in adult patients with ML.

Comparing 18-fluoro-2-deoxyglucose positron emission tomography with a combination of technetium 99m tetrofosmin single photon emission computed tomography and computed tomography to detect recurrent or persistent nasopharyngeal carcinomas after radiotherapy

BACKGROUND

The diagnostic accuracy of combined computed tomography (CT) and technetium 99m tetrofosmin (Tc-TF) single photon emission computed tomography (SPECT) of head and neck to differentiate recurrent or residual nasopharyngeal carcinomas (NPCs) from benign lesions after radiotherapy was evaluated and compared with positron emission tomography (PET) with 18-fluoro-2-deoxyglucose (FDG).

METHODS

Four months after radiotherapy, 36 patients with NPC underwent Tc-TF SPECT and CT of head and neck to differentiate recurrent or residual NPC from benign lesions. Histopathologic examinations were performed on nasopharyngeal biopsies of all 36 patients.

RESULTS

Based on the biopsy results, the sensitivity, specificity, and accuracy of Tc-TF SPECT were 64%, 96%, and 86%, respectively, for differentiation of recurrent or persistent NPC from benign lesions. For CT and FDG-PET, the sensitivity, specificity, and accuracy were 73%, 88%, and 83% and 100%, 96%, 97%, respectively. For the 27 patients with NPC whose Tc-TF SPECT and CT results were congruent, the combination of Tc-TF SPECT and CT had the same sensitivity, specificity, and accuracy (100%, 96%, and 96%) as FDG-PET. For the nine patients with NPC with incongruent Tc-TF SPECT and CT results, FDG-PET correctly differentiated two benign lesions from seven recurrent/residual NPCs.

CONCLUSIONS

Although, FDG-PET is the best tool for detecting recurrent or residual NPC, combined congruent Tc-TF SPECT and CT results achieved the same accuracy as FDG-PET. Therefore, we concluded that FDG-PET could be considered only when Tc-TF SPECT and CT give incongruent results.

Using radionuclide esophageal emptying test to evaluate pneumatic dilatation effects for achalasia

BACKGROUND/AIMS

Radionuclide esophageal emptying test using a solid meal is a simple, noninvasive, and physiologic test of esophageal function.

METHODOLOGY

In this study, we evaluated esophageal emptying using an isotope-labeled solid meal (an egg salad sandwich labeled with 99mTc-MAA) in the assessment of pneumatic dilatation treatment in achalasia. Twenty achalasic patients (12 males, 8 females, age: 51.4 +/- 13.0 years) underwent esophageal emptying measurement before and after pneumatic dilatation. After treatment, the dysphagic symptoms of all patients improved.

RESULTS

In comparison with the pretreatment test, the posttreatment retention fraction at 1, 5, 10, and 15 min were significantly lower (P < 0.001).

CONCLUSIONS

The results suggest that radionuclide esophageal emptying test using a solid meal remains a useful objective study of esophageal function and may have an important future role in the follow-up evaluation of treatment for achalasia.

[The development of a competency-based clinical performance examination model in maternity nursing for BSN graduates]

The purpose of the study was to establish a competency-based clinical performance examination model in maternity nursing for baccalaureate students. Action research was the main research methodology used in the study. A committee, consisting of nursing faculty, students and experienced obstetric nurses, was established to develop the model. Based on intensive literature reviews and standards of nursing practice in Taiwan, the first draft of the model, including the content and process, was created by the committee. The draft then was revised twice after expert review and pilot testing. The revised version of the model was formally implemented into the curriculum to examine the competencies of forty-one BSN students at the end of the perinatal nursing course. Responses from students, clinical examiners, clinical staff and clients were all gathered and integrated to refine the model. The model has content, expert and discriminative validity. The reliability of the model was proven by the high consistency in administration and scoring of the model among clinical examiners.