Spatiotemporal characterization of PM2.5, O3, and trace gases associated with East Asian continental outflows via drone sounding

East Asian continental outflows with PM2.5, O3, and other species may determine the baseline conditions and affect the air quality in downwind areas via long-range transport (LRT). To gain insight into the impact and spatiotemporal characteristics of airborne pollutants in East Asian continental outflows, a versatile multicopter drone sounding platform was used to simultaneously observe PM2.5, O3, CO2, and meteorological variables (temperature, specific humidity, pressure, and wind vector) above the northern tip of Taiwan, Cape Fuiguei, which often encounters continental outflows during winter monsoon periods. By coordinating hourly high-spatial-resolution profiles provided by drone soundings, WRF/CMAQ model air quality predictions, HYSPLIT-simulated backward trajectories, and MERRA-2 reanalysis data, we analyzed two prominent phenomena of airborne pollutants in continental outflows to better understand their physical/chemical characteristics. First, we found that pollutants were well mixed within a sounding height of 500 m when continental outflows passed through and completely enveloped Cape Fuiguei. Eddies induced by significant fluctuations in wind speeds coupled with minimal temperature inversion and LRT facilitated vertical mixing, possibly resulting in high homogeneity of pollutants within the outflow layer. Second, the drone soundings indicated exceptionally high O3 concentrations (70-100 ppbv) but relatively low concentrations of PM2.5 (10-20 μg/m3), CO2 (420-425 ppmv), and VOCs in some air masses. The low levels of PM2.5, CO2, and VOCs ruled out photochemistry as the cause of the formation of high-level O3. Further coordination of spatiotemporal data with air mass trajectories and O3 cross sections provided by MERRA-2 suggested that the high O3 concentrations could be attributed to stratospheric intrusion and advection via continental outflows. High-level O3 concentrations persisted in the lower troposphere, even reaching the surface, suggesting that stratospheric intrusion O3 may be involved in the rising trend in O3 concentrations in parts of East Asia in recent years in addition to surface photochemical factors.

INPP5E regulates CD3ζ enrichment at the immune synapse by phosphoinositide distribution control

The immune synapse, a highly organized structure formed at the interface between T lymphocytes and antigen-presenting cells (APCs), is essential for T cell activation and the adaptive immune response. It has been shown that this interface shares similarities with the primary cilium, a sensory organelle in eukaryotic cells, although the roles of ciliary proteins on the immune synapse remain elusive. Here, we find that inositol polyphosphate-5-phosphatase E (INPP5E), a cilium-enriched protein responsible for regulating phosphoinositide localization, is enriched at the immune synapse in Jurkat T-cells during superantigen-mediated conjugation or antibody-mediated crosslinking of TCR complexes, and forms a complex with CD3ζ, ZAP-70, and Lck. Silencing INPP5E in Jurkat T-cells impairs the polarized distribution of CD3ζ at the immune synapse and correlates with a failure of PI(4,5)P2 clearance at the center of the synapse. Moreover, INPP5E silencing decreases proximal TCR signaling, including phosphorylation of CD3ζ and ZAP-70, and ultimately attenuates IL-2 secretion. Our results suggest that INPP5E is a new player in phosphoinositide manipulation at the synapse, controlling the TCR signaling cascade.

TRABID inhibition activates cGAS/STING-mediated anti-tumor immunity through mitosis and autophagy dysregulation

Activation of tumor-intrinsic innate immunity has been a major strategy for improving immunotherapy. Previously, we reported an autophagy-promoting function of the deubiquitinating enzyme TRABID. Here, we identify a critical role of TRABID in suppressing anti-tumor immunity. Mechanistically, TRABID is upregulated in mitosis and governs mitotic cell division by removing K29-linked polyubiquitin chain from Aurora B and Survivin, thereby stabilizing the entire chromosomal passenger complex. TRABID inhibition causes micronuclei through a combinatory defect in mitosis and autophagy and protects cGAS from autophagic degradation, thereby activating the cGAS/STING innate immunity pathway. Genetic or pharmacological inhibition of TRABID promotes anti-tumor immune surveillance and sensitizes tumors to anti-PD-1 therapy in preclinical cancer models in male mice. Clinically, TRABID expression in most solid cancer types correlates inversely with an interferon signature and infiltration of anti-tumor immune cells. Our study identifies a suppressive role of tumor-intrinsic TRABID in anti-tumor immunity and highlights TRABID as a promising target for sensitizing solid tumors to immunotherapy.

TFEB- and TFE3-dependent autophagy activation supports cancer proliferation in the absence of centrosomes

Centrosome amplification is a phenomenon frequently observed in human cancers, so centrosome depletion has been proposed as a therapeutic strategy. However, despite being afflicted with a lack of centrosomes, many cancer cells can still proliferate, implying there are impediments to adopting centrosome depletion as a treatment strategy. Here, we show that TFEB- and TFE3-dependent autophagy activation contributes to acentrosomal cancer proliferation. Our biochemical analyses uncover that both TFEB and TFE3 are novel PLK4 (polo like kinase 4) substrates. Centrosome depletion inactivates PLK4, resulting in TFEB and TFE3 dephosphorylation and subsequent promotion of TFEB and TFE3 nuclear translocation and transcriptional activation of autophagy- and lysosome-related genes. A combination of centrosome depletion and inhibition of the TFEB-TFE3 autophagy-lysosome pathway induced strongly anti-proliferative effects in cancer cells. Thus, our findings point to a new strategy for combating cancer.Abbreviations: AdCre: adenoviral Cre recombinase; AdLuc: adenoviral luciferase; ATG5: autophagy related 5; CQ: chloroquine; DAPI: 4',6-diamidino-2-phenylindole; DKO: double knockout; GFP: green fluorescent protein; KO: knockout; LAMP1: lysosomal associated membrane protein 1; LAMP2: lysosomal associated membrane protein 2; LTR: LysoTracker Red; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MITF: melanocyte inducing transcription factor; PLK4: polo like kinase 4; RFP: red fluorescent protein; SASS6: SAS-6 centriolar assembly protein; STIL: STIL centriolar assembly protein; TFEB: transcription factor EB; TFEBΔNLS: TFEB lacking a nuclear localization signal; TFE3: transcription factor binding to IGHM enhancer 3; TP53/p53: tumor protein p53.

Distinct transport mechanisms of East Asian dust and the impact on downwind marine and atmospheric environments

East Asian dust episodes have a multitude of impacts, including on human health, environment, and climate over near-source and receptor regions. However, the mechanistic understanding of the synoptic conditions of these outbreaks at different altitude layers, and their eventual environmental impacts are less studied. The present study analyzed the synoptic transport patterns of East Asian dust during multiple dust generation episodes that occurred over only a few days apart in northern China, and which eventually delivered high PM₁₀ concentrations to surface level and high-altitude locations in Taiwan. Whether the dust plume was uplifted ahead of or behind the 700 hPa trough over East Asia determined its trajectory and eventual impact on the environment downwind. The total dust (iron) deposition over the ocean surface preceding arrival to Taiwan was 2.4 mg m^-2 (0.95 μg m^-2) for the episode impacting the surface level and 5.0 mg m^-2 (4.6 μg m^-2) for the episode impacting high-altitude Taiwan. Dust deposition in marine areas east of China was more intense for the higher altitude transport event that was uplifted behind the 700 hPa trough and resulted in twice higher marine Chl-a concentrations. Furthermore, we estimated a dust-induced direct radiative effect over a high mountainous region in Taiwan of -6.2 to -8.2 W m^-2 at the surface, -1.9 to -2.9 W m^-2 at the top of the atmosphere and +3.9 to +5.3 W m^-2 in the atmosphere. This dust-induced atmospheric warming and surface cooling are non-negligible influences on the atmospheric thermal structure and biogeochemical cycle over the western North Pacific. Overall, this study highlights the significant impacts of dust particles on the marine ecosystem and atmospheric radiation budget over the downwind region, thus lays the foundation for linking these impacts to the initial synoptic conditions in the source area.

[Efficacy and safety of anti-PD-1 monoclonal antibody in advanced hepatocellular carcinoma after TACE combined with TKI therapy]

Objective: To evaluate the efficacy and safety of anti-programmed cell death 1 (PD-1) receptor monoclonal antibody (MoAb) in patients with advanced hepatocellular carcinoma (HCC) after treatment of transcatheter arterial chemoembolization (TACE) combined with tyrosine kinase inhibitor (TKI). Methods: From February 2019 to February 2020, 56 HCC patients who relapsed after TACE-TKI treatment in Department of Interventional Radiology, The Second Affiliated Hospital of Guangzhou Medical University were enrolled. All patients received anti-PD-1 MoAb (sintilimab injection) and followed up every 6 weeks. According to mRECIST, the curative effect was evaluated as complete response (CR), partial response (PR), stable disease (SD) or progressive disease (PD). Objective response rate (ORR) and disease control rate (DCR), progression-free survival (PFS) and treatment-related adverse events (TRAEs) were recorded. Univariate analysis by Chi-square test and binary logistic regression model was used to determine the influencing factors of DCR. The Kaplan-Meier method and Cox proportional hazard regression model were used to analyze the survival data. Results: A total of 48 patients were enrolled in this study including 42 males and 6 females, with a median age of 55 years (29-71 years). ECOG scores comprised of 0 in 24 cases, 1-2 in 24 cases. Thirty-six patients were in Child-Pugh grade A of liver function and 12 cases were grade B. The median follow-up time was 4.5 months. There were 2 patients achieved CR, 12 patients with PR and 16 with SD. ORR was 29.2%, DCR was 62.5%. The independent influencing factors of DCR was ECOG score and AFP level (P=0.031, P=0.012). Median PFS was 4.1 months (95%CI 2.7-5.4 months), and ECOG score was the independent influencing factor of PFS (P=0.042). Treatment-related adverse events were reported in 70.8% (34/48) patients. Incidence of grade Ⅲ-Ⅳ TRAEs was 22.9% (11/48). Conclusion: In patients with HCC who relapse from TACE and TKI treatment, anti-PD-1 monoclonal antibody is efficacious safe especially in those with ECOG 0 score.

Long-range air pollution transport in East Asia during the first week of the COVID-19 lockdown in China

Long-range transport (LRT) of air pollutants from East Asia during the northeast monsoon season impacts several downwind locations. In 2020, the initial COVID-19 lockdowns in China overlapped with Week 3 of the Chinese New Year (CNY) holiday, and an Asian outflow event. Thus, movement of the Chinese populace from city to city was already greatly reduced by the time of the LRT episode, although the reductions in industrial output are less clear. We found NO₂ column concentrations were reduced by 24% during the CNY Week 3 this year compared to previous years. The attenuated transport event arrived to northern Taiwan with a PM_2.5 concentration <45 μg m^-3 and most often <35 μg m^-3, which is 2-3 times lower than LRT episodes of similar back-trajectory and synoptic patterns. The whole episode persisted for about 60 h, longer than most LRT episodes from China to Taiwan. CMAQ v5.2.1 modeling of the LRT event with 100% emission and reduced emission scenarios, revealed emissions in China were approximately 50% less than normal periods. Due to the length of the episode and the significant reduction in emissions, Taiwan avoided a PM_2.5 surplus of 19.2 μg m^-3 on average during the episode, equivalent to a 0.5 μg m^-3 reduction for the whole 3-month winter season. Employing the 100% emission model scenario and scaling up to the average episode hours each winter, the PM_2.5 surplus delivered via plumes on the northeast monsoon is equivalent to a 0.5 μg m^-3 surplus for the whole year.

Lamin A-mediated nuclear lamina integrity is required for proper ciliogenesis

The primary cilium is a sensory organelle that receives specific signals from the extracellular environment important for vertebrate development and tissue homeostasis. Lamins, the major components of the nuclear lamina, are required to maintain the nuclear structure and are involved in most nuclear activities. In this study, we show that deficiency in lamin A/C causes defective ciliogenesis, accompanied by increased cytoplasmic accumulation of actin monomers and increased formation of actin filaments. Disruption of actin filaments by cytochalasin D rescues the defective ciliogenesis in lamin A/C-depleted cells. Moreover, lamin A/C-deficient cells display lower levels of nesprin 2 and defects in recruiting Arp2, myosin Va, and tau tubulin kinase 2 to the basal body during ciliogenesis. Collectively, our results uncover a functional link between nuclear lamina integrity and ciliogenesis and implicate the malfunction of primary cilia in the pathogenesis of laminopathy.

Identification of a novel splice variant isoform of interferon regulatory factor 10, IRF10, in orange spotted grouper Epinephelus coioides

Interferon regulatory factors (IRFs) are a family of transcription factors essential to the control of antiviral immune response, cell growth, differentiation and apoptosis. IRF10 was originally found in chicken, which was induced by the v-Rel oncoprotein in lymphoid cell lines and involved in the upregulation of major histocompatibility complex (MHC) class I and guanylate-binding protein. In fish, IRF10 plays negative roles in regulation of the interferon (IFN) response. Here, we identified a splice variant of IRF10, named as EcIRF10-SF in orange spotted grouper, which shares the first three exons with the long form (EcIRF10-LF) and retains part of intron 3, creating a premature termination codon. Furthermore, we observed that the EcIRF10-SF exhibits similar expression pattern compared to its native counterparts. Functional studies demonstrate that the two EcIRF10 isoforms repress DrIFNϕ1 and DrIFNϕ3 promoter activity and negatively regulate fish antiviral gene expression. Subcellular localization analysis shows that the amino acids from 57 to 86 within DBD are required for IRF10 nuclear import. Overall, our description of transcript diversification of IRF10 in the grouper provides a coherent framework to further dissect its roles in immune response.

Identification of a novel RIG-I isoform and its truncating variant in Japanese eel, Anguilla japonica

Retinoic acid-inducible gene-I (RIG-I) is a cytoplasmic viral RNA sensor that triggers the production of type I interferons (IFNs) and proinflammatory cytokines during viral infection. RIG-I gene has been identified previously in Japanese eel, Anguilla japonica. In the present study, we have characterized a novel isoform of RIG-I (designated as AjRIG-Ib) and its truncated variant (AjRIG-Ibv). The AjRIG-Ib encodes 940 amino acids (aa) consisting of two N-terminal caspase activation and recruitment domains (CARDs), a DEX(D/H) box RNA helicase domain, and a C-terminal regulatory domain (CTD). The AjRIG-Ibv encodes a protein of 843 aa, that shares similar structural organization with AjRIG-Ib, but lacking CTD. The gene expression analyses showed that AjRIG-Ib and AjRIG-Ibv were detectable in all tissues/organs examined, and AjRIG-Ib was the predominant form. The mRNA level of AjRIG-Ibv was upregulated rapidly at 8 h after the Poly I:C injection, and the significant increase of AjRIG-Ib was observed at 16 and 24 h post-injection (hpi). Laser confocal microscopy showed that AjRIG-Ib and AjRIG-Ibv were both located in cytoplasm. In addition, the overexpression of AjRIG-Ib or AjRIG-Ibv led to the increased activity of IFN promoter in transient transfection assay. Taken together, our results indicated that AjRIG-Ib and AjRIG-Ibv may play cooperative or somewhat complementary roles in coordinating the antiviral response in fish.

Analysis of 4 Cases of Electrocution due to Direct Current Electronic Hunter

Abstract

Objective To summarize the characteristics of cases of electrocution due to direct current （DC） electronic hunter, and to provide references for forensic identification. Methods Four cases of electrocution due to DC electronic hunter were collected. Statistical analysis was carried out from the perspective of the scene and electric marks distribution, damage characteristics and histopathological changes. Results All the 4 cases of electrocution were accidental events. There were multiple electric marks, most of which were located in the lower limbs with serious damage. Some strip type electric marks were visible. Conclusion The distribution, morphological characteristics and severity of the electric marks caused by DC electronic hunter are different from those of the ordinary low-voltage alternating current damage. It is alerting that there would be actions of destroying the scene and abandoning the corpse in such cases.

[Etiological analysis and establishment of a discriminant model for lower respiratory tract infections in hospitalized patients]

Objective: To analyze the pathogens of lower respiratory tract infection(LRTI) including bacterial, viral and mixed infection, and to establish a discriminant model based on clinical features in order to predict the pathogens. Methods: A total of 243 hospitalized patients with lower respiratory tract infections were enrolled in Fujian Provincial Hospital from April 2012 to September 2015. The clinical data and airway (sputum and/or bronchoalveolar lavage) samples were collected. Microbes were identified by traditional culture (for bacteria), loop-mediated isothermal amplification(LAMP) and gene sequencing (for bacteria and atypical pathogen), or Real-time quantitative polymerase chain reaction (Real-time PCR)for viruses. Finally, a discriminant model was established by using the discriminant analysis methods to help to predict bacterial, viral and mixed infections. Results: Pathogens were detected in 53.9% (131/243) of the 243 cases.Bacteria accounted for 23.5%(57/243, of which 17 cases with the virus, 1 case with Mycoplasma pneumoniae and virus), mainly Pseudomonas Aeruginosa and Klebsiella Pneumonia. Atypical pathogens for 4.9% (12/243, of which 3 cases with the virus, 1 case of bacteria and viruses), all were mycoplasma pneumonia. Viruses for 34.6% (84/243, of which 17 cases of bacteria, 3 cases with Mycoplasma pneumoniae, 1 case with Mycoplasma pneumoniae and bacteria) of the cases, mainly Influenza A virus and Human Cytomegalovirus, and other virus like adenovirus, human parainfluenza virus, respiratory syncytial virus, human metapneumovirus, human boca virus were also detected fewly. Seven parameters including mental status, using antibiotics prior to admission, complications, abnormal breath sounds, neutrophil alkaline phosphatase (NAP) score, pneumonia severity index (PSI) score and CRUB-65 score were enrolled after univariate analysis, and discriminant analysis was used to establish the discriminant model by applying the identified pathogens as the dependent variable. The total positive predictive value was 64.7%(77/119), with 66.7% for bacterial infection, 78.0% for viral infection and 33.3% for the mixed infection. Conclusions: The mostly detected pathogens were Pseudomonas aeruginosa, atypitcal pathogens, Klebsiella pneumoniae, influenza A virus and human cytomegalovirus in hospitalized patients with LRTI in this hospital. The discriminant diagnostic model established by clinical features may contribute to predict the pathogens of LRTI.

Identification of four type I IFNs from Japanese eel with differential expression properties and Mx promoter inducibility

Type I IFNs are a family of cytokines with antiviral, anti-proliferative and immune-modulatory functions. In this study, four type I IFNs (termed AjIFN1-4) have been cloned from the Japanese eel, Anguilla japonica. The open reading frames of AjIFN1-4 are 552, 534, 546 and 561 bp in length, encoding 183, 177, 181, and 186 amino acids (aa), respectively. Sequence comparison and phylogenetic analysis results revealed that AjIFN1 and AjIFN2 belong to group one (2C-containing) IFNs, while AjIFN3 and AjIFN4 belong to group two (4C-containing) IFNs. Syntenic comparison showed that chromosome block duplication and rearrangement events might have occurred at IFN loci in different teleost lineages. Expression analysis revealed the rapid induction of AjIFNl and AjIFN2 in response to poly I:C stimulation, while AjIFN3 and AjIFN4 were predominantly expressed at later time points. Two Mx promoter reporter assays were conducted to assess the Mx-inducing capability of AjIFN1-4. It is shown that the overexpression of AjIFN1-4 all promoted the luciferase activity of MxB reporter, but the activity of MxC reporter increased only in cells transfected with AjIFN1. Collectively, it is suggested that teleost IFNs were evolved independently in different lineages of fish and may function differently in teleost antiviral immunity.

Characterization of MyD88 in Japanese eel, Anguilla japonica

Myeloid differentiation factor 88 (MyD88) is a key adaptor protein required for the signaling of all Toll-like receptors except TLR3, which results to the interaction of activated TLR complexes via C-terminal TIR domain and the binding of downstream kinase via N-terminal death domain. In this study, the MyD88 gene from the Japanese eel (Anguilla japonica) was identified. The open reading frame of AjMyD88 was 918 bp in length, encoding a protein composed of conserved N-terminal death domain and C-terminal TIR domain, respectively. Multiple alignment revealed highly conserved sites across all examined vertebrate lineages in death and TIR domains. Site-directed mutagenesis and luciferase analysis revealed that the W78A, L91A and L95A mutations in death domain had modest impairment of their ability in activating NF-κB promoter. The expression level of AjMyD88 was investigated by real-time PCR in response to poly I:C stimulation and Edwardsiella tarda infection. Significantly increased MyD88 expression was observed at early phase in all tested tissues/organs in response to E. tarda infection and slight increase was detected in intestine and gill at 16 hpi and in head kidney, spleen and liver at 24 hpi after poly I:C stimulation. Immunofluorescence staining revealed that AjMyD88 is present as condensed forms in the cytoplasm. Taken together, sequence characterization, gene expression and cellular distribution data obtained in this study suggest that AjMyD88, similar to its mammalian ortholog, plays an important role in eel immune response against bacteria.

FlgN plays important roles in the adhesion of Aeromonas hydrophila to host mucus

Adhesion to the host mucus is a crucial step in the early infection stage of pathogenic bacteria. To investigate the mechanisms of the adhesion of Aeromonas hydrophila to its host mucus, a mutant library was constructed using the mini-Tn10 transposon mutagenesis system. Of 276 individual colonies, the mutant strain with the most attenuated adhesion ability in this study was screened out and designated A77. Molecular analysis showed that a 414-bp sequence flanking mini-Tn10 in A77 had the highest identity (97%) with the bacterial flagellar protein gene flgN. A complemented strain flgN+ was constructed and the biological characteristics of the wild-type, mutant A77, and complemented flgN+ strains were investigated. The results showed that the decreased abilities of motility, adhesion to mucus, and biofilm formation in the mutant strain were partially recovered in the complemented flgN+ strain, which suggested that flgN plays an important role in the adhesion of A. hydrophila to its host.

Persistent sterile pyuria in children? Don't forget tuberculosis!

Genitourinary tuberculosis (GUTB) is exceptionally uncommon among the local paediatric population. A 10-year-old Chinese girl with no risk factors for tuberculosis presented with recurrent sterile pyuria. Despite extensive renal investigations, no apparent cause could be ascertained for her obstructed left drainage system. The diagnosis was eventually confirmed with urine acid-fast bacilli culture, after a computed tomography scan suggested possible renal tuberculosis. Left nephroureterectomy had to be performed owing to deteriorating left kidney function. This report discusses the importance of considering tuberculosis when assessing a local paediatric patient with an atypical urinary tract infection. Early diagnosis of renal tuberculosis can prevent the sequelae of GUTB, including renal impairment.

Thallium-201 SPECT predicts response to intensity-modulated radiation therapy for recurrent oral squamous cell carcinoma

The aim of this study was designed to investigate the usefulness of thallium-201 single photon emission computed tomography (SPECT) in predicting response of intensity-modulated radiation therapy (IMRT) for recurrent oral squamous cell carcinoma (OSCC).

PATIENTS, METHODS

Thirty-one patients with histologically proven recurrent OSCC were recruited. Before IMRT, all patients underwent SPECT at 15 min and 120 min after intravenous injection 111 MBq of thallous chloride ((201)Tl). Tumour uptake was measured with the semiquantitative early ratio (ER), delayed ratio (DR), and retention index (RI). The patients were classified into responder (complete response and partial response) and non-responder (stable disease and progressive disease) groups according to the tumour response evaluated by the Response Evaluation Criteria in Solid Tumors guidelines.

RESULTS

As comparing DR and RI between the two groups, both parameters were significantly higher in the responder group. When a DR of 1.75 was used as a cutoff value for the responders, the receiver operating characteristic (ROC) analyses revealed sensitivity and specificity of 79% and 75%, respectively. At a cutoff value for the responders of a RI of 78.5%, the ROC analyses showed sensitivity and specificity of 95% and 83%, respectively.

CONCLUSION

Our results suggest that (201)Tl-SPECT, as measured by the DR or RI has clinical potential in predicting response of IMRT for patients with recurrent OSCC. The ROC curve analyses further suggest that RI may be superior to DR in distinguishing responders from non-responders.

Five years' experience of the modified Meek technique in the management of extensive burns

BACKGROUND

The Meek technique of skin expansion is useful for covering a large open wound with a small piece of skin graft, but requires a carefully followed protocol.

METHODS

Over the past 5 years, a skin graft expansion technique following the Meek principle was used to treat 37 individuals who had sustained third degree burns involving more than 40% of the body surface. A scheme was devised whereby the body was divided into six areas, in order to clarify the optimal order of wound debridements and skin grafting procedures as well as the regimen of aftercare.

RESULTS

The mean body surface involvement was 72.9% and the mean area of third degree burns was 41%. The average number of operations required was 1.84. There were four deaths among in this group of patients.

CONCLUSIONS

The Meek technique of skin expansion and the suggested protocol are together efficient and effective in covering an open wound, particularly where there is a paucity of skin graft donor sites.

Thallium-201 scan in evaluating thyroid nodules following equivocal fine-needle aspiration cytology

The AIM of this prospective study was to evaluate the usefulness of the thallium-201 ( (201) Tl) thyroid scan in the detection of malignancy in cold thyroid nodules whose status was equivocal following palpation fine-needle aspiration cytology (FNAC).

PATIENTS, METHODS

Fifty-one patients with clinically palpable solitary cold thyroid nodules classified as non-diagnostic or suspicious following biopsy underwent (201) Tl thyroid scans. Each scan was performed 15 min (early scan) and 3 h (delayed scan) after an intravenous administration of 74 MBq (201) Tl. Thallium uptake in the nodules was visually assessed and scored on a three point scale, with a grade of three defining malignancy. All patients underwent surgery and the histopathology of nodule tissues were compared with results of the scans.

RESULTS

Fifty-one nodules were examined. Forty were benign and 11 were malignant. For early scans, the diagnostically relevant parameters were: sensitivity (100%), specificity (75%), and accuracy (80%). Corresponding findings for the delayed scan were: 91%, 98%, and 96%.

CONCLUSION

The (201) Tl scan is useful for detecting malignancy in cold thyroid nodules classified as nondiagnostic or suspicious lesions by FNAC.

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.

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.

Detecting abnormal regional cerebral blood flow in patients with primary Sjögren's syndrome by technetium-99m ethyl cysteinate dimer single photon emission computed tomography of the brain--a preliminary report

Technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) was used to detect abnormal regional cerebral blood flow (rCBF) in 32 female patients with primary Sjögren's syndrome (PSS) showing definite neuropsychiatric symptoms/signs and normal brain magnetic resonance imaging (MRI) findings. It demonstrated hypoperfusion brain lesions in 18 (56.3%) of the patients, most frequently in the parietal lobes, and appears to be a sensitive tool for this clinical application.

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.

Abnormal 201Tl myocardial single photon emission computed tomography in energetic male patients with myocardial bridge

Myocardial bridge is a relatively benign condition where a major coronary artery is bridged by a band of muscle and narrows during systole, particularly during rapid heart rates. Its clinical presentation and electrocardiogram (ECG) changes overlap with that of coronary artery disease. 201Tl myocardial perfusion imaging is thus frequently prescribed for further evaluation. This retrospective study was carried out to determine the 201Tl image patterns in patients with myocardial bridge. A total of 17 male patients (aged from 30 to 63 years) who had a positive exercise ECG and angiographic evidence of myocardial bridge in the mid-third of the left anterior descending coronary artery were recruited. Most of them were robust and received routine physical check-ups. They had no known heart disease or medication that affected cardiac function. The patients' clinical presentations, echocardiograph and exercise ECG findings were analysed. 201Tl single photon emission computed tomography (SPECT) was performed by intravenous injection of 201Tl (111 MBq) immediately following stress (treadmill or dipyridamole induced) and 4 h after stress, using a fixed, right angle camera equipped with a low energy, general purpose collimator. The images were interpreted independently by two experienced nuclear medicine physicians. Nine of the 17 patients had anterior chest pain during exercise. All patients had an abnormal ECG during exercise, including ST-T wave depression in leads II, III and aVF, and v4-6. Except for eight patients revealing reversible perfusion defect (R), 16 of the 17 patients also exhibited a partial reversible perfusion defect (PR) or a significant reverse redistribution (RR) scan pattern in the anterior or inferior walls of the left ventricle. Myocardial bridge should be taken into consideration in energetic male patients who had abnormal exercise ECGs and the corresponding patterns of Tl SPECT abnormalities including R, PR and RR.

Objective evidence of abnormal regional cerebral blood flow in patients with systemic lupus erythematosus on Tc-99m ECD brain SPECT

Technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) was used to detect abnormal regional cerebral blood flow (rCBF) in 78 SLE patients with neuropsychiatric manifestations. These patients were separated into two subgroups: group 1 including 48 cases with definite neuropsychiatric symptoms/signs and group 2 with 30 cases having no neuropsychiatric symptoms/signs. Tc-99m ECD brain SPECT demonstrated hypoperfusion brain lesions in 90% and 20% of patients in groups 1 and 2, respectively. In both groups, parietal lobe and cerebellum are the most and least common areas with hypoperfusion lesions, respectively. This study suggests that Tc-99m ECD brain SPECT may provide objective information for detection of hypoperfusion brain lesions in SLE patients.

The role of dopamine transporter imaging agent [99mTc]TRODAT-1 in hemi-parkinsonism rat brain

This study aims to investigate the relationship between the determination of dopamine level by high performance liquid chromatography (HPLC) with electrochemical detection (ECD) and the detection of dopamine transporter (DAT) counts using autoradiography with DAT image agent [99mTc]TRODAT-1. For striatal lesions, pretreatment of 6-hydroxydopamine (6-OHDA) in the medial forebrain bundle shows that autoradiogaphic labeling of striatum region is reduced to near-background level. Using HPLC with ECD, unilateral 6-OHDA treatment is associated with significant (p < 0. 0002) reductions of dopamine levels. For the striatum of the 6-OHDA-lesioned side, dopamine content and DAT counts are reduced to 97% and 90%, respectively. Thus, our observation indicates a potential of using [99mTc]TRODAT-1 for the evaluation of animal DAT.

Evaluation of early-stage Parkinson's disease with 99mTc-TRODAT-1 imaging

Parkinson's disease is a progressive neurodegenerative disorder characterized by a selective loss of dopamine in the striatum. Problems remain in the accurate diagnosis of Parkinson's disease. A 99mTc-labeled tropane derivative that binds to dopamine transporter with high selectivity is [2-[[2-[[[3-(4-chlorophenyl)-8-methyl-8-azabicyclo[3,2,1]oct-2-yl]methyl](2-mercaptoethyl)amino]ethyl]amino]ethanethiolato(3-)-N2,N2',S2,S2']oxo-[1R-(exo-exo)] (TRODAT-1). The purpose of this study was to investigate the potential usefulness of 99mTc-TRODAT-1 imaging in the evaluation of patients with early-stage Parkinson's disease.

METHODS

Thirty-four patients with early-stage idiopathic Parkinson's disease were recruited. For all patients, the Parkinson's disease was stage 2 or less as assessed by the Hoehn and Yahr scale. Seventeen age-matched healthy volunteers (8 men, 9 women) served as controls. 99mTc-TRODAT-1 was prepared from a lyophilized kit. Brain SPECT imaging was performed between 165 and 195 min after injection, using a double-head camera equipped with fanbeam collimators. Specific uptake in the striatum and its subregions, including the putamen and caudate nucleus, was calculated and compared with that of the other sides and of healthy volunteers.

RESULTS

A continuous reduction in specific striatal uptake of 99mTc-TRODAT-1 with increasing disease severity was found in Parkinson's disease patients (control vs. stage I vs. stage II, 1.98 vs. 1.62 vs. 1.22, respectively, P < 0.01). The changes were magnified by measurement of specific putaminal uptake (control vs. stage I vs. stage II, 1.81 vs. 1.27 vs. 0.94, respectively, P < 0.01). The mean values of specific putaminal uptake contralateral to the more affected limbs were significantly decreased compared with the ipsilateral sides in both stage I and stage II groups (1.02 vs. 1.49 for stage I and 0.73 vs. 1.14 for stage II, P < 0.01). Moreover, a significant loss of putaminal uptake ipsilateral to the symptoms was found in the stage I group compared with the healthy volunteers (1.49 vs. 1.81, P < 0.01). The difference became greater when the posterior putaminal uptakes were compared. No remarkable adverse reactions were found in either healthy volunteers or Parkinson's disease patients during or after imaging.

CONCLUSION

For clinical practice, 99mTc-TRODAT-1 may serve as a useful imaging agent for the early detection of Parkinson's disease.

3,3'-Diiodothyronine sulfate excretion in maternal urine reflects fetal thyroid function in sheep

We have shown that there is significant fetal-to-maternal transfer of sulfated metabolites of thyroid hormone after fetal infusion of a pharmacologic amount of 3,3',5-triiodothyronine (T(3)) or sulfated T(3) in late pregnancy in sheep (Am J Physiol 277:E915, 1999). The transferred iodothyronine sulfoconjugate, i.e. 3,3'-diiodothyronine sulfate (T(2)S), of fetal origin appears in maternal sheep urine. The present study was carried out to assess the contribution of T(2)S of fetal origin to the urinary pool in ewes. Eighteen date-bred ewes (mean gestational age of 115 d) and their twin fetuses were divided into four groups. In group I (control, n = 5), both ewes (M) and their fetuses (F) were sham operated for thyroidectomy (Tx). In group II, the ewes (MTx, n = 4) and, in group III, the fetuses (FTx, n = 4) were subjected to Tx. In group IV (MTx.FTx, n = 5), both the ewe and fetus had Tx. After 10-12 d, fetal and/or maternal hypothyroidism were confirmed by serum thyroxine (<15 nmol/L) measurements. In addition, we infused radioactive T(3) without disturbing the T(3) pool in three singleton near-term fetuses and assessed the amount of radioactive iodothyronine that appeared in maternal urine (MU). After infusing [(125)I-3'],3,5-T(3) via fetal vein to the near-term normal fetuses, radioactive T(2)S was identified as the major metabolite in MU by HPLC and T(2)S-specific antibody. MU T(2)S excretion (pmol/mmol creatinine) was significantly reduced by FTx and MTx.FTx but not by MTx. In addition, positive correlations (p < 0.01) were found between MU T(2)S excretion and fetal serum thyroxine and T(3) concentrations but not with maternal serum thyroxine or T(3) levels. T(2)S of fetal origin contributes significantly to the MU pool.

The effect of fasting on the pulse spectrum

Nutrition is the major source of bioenergy. The present study investigated the physiological response to fasting by analyzing the effect of fasting on the pulse spectrum of the radial artery. Sixteen subjects were allowed to take only mineral water for 24 hours, and the pulse was measured at intervals during fasting and after eating resumed. Data were analyzed using one-way analysis of variance (ANOVA) with Scheffe's test for pairwise comparisons. The results indicate the second harmonic of the radial pulse increased and the sixth harmonic decreased significantly after 24 hours of fasting. The proportions of the second harmonic then decreased significantly and those of the sixth harmonic increased significantly 12 hours after eating resumed. These findings suggest that a rhythm exists in physiological changes and the distribution of bioenergy, which ensures that the overall heart load will remain unchanged during the fasting and re-feeding periods, maintaining a stable overall balance in body function.

Biaryl-based macrocyclic and polymeric chiral (salophen)Ni(II) complexes: synthesis and spectroscopic study

Polymeric/oligomeric and macrocyclic (salophen)Ni(II) complexes have been synthesized starting from both an achiral biphenol dialdehyde and an optically active BINOL dialdehyde. It was found that these polysalophens contain nonplanar coordination of Ni(II) units that are paramagnetic. This is different from the previously reported (salophen)Ni(II) complexes which are square planar and diamagnetic. The nonplanar (salophen)Ni(II) units make the new polymeric Ni(II) complexes different from the helical structure proposed for chiral biaryl-based polymers containing square-planar (salophen)Ni(II) units. The copolymerization of the chiral binaphthyl monomer with the achiral biphenyl monomer demonstrates that the chirality of the binaphthyl unit is not propagated along the biphenyl polymer chain.

Iliofemoral vein thrombosis and pulmonary embolism associated with a transient ischemic attack in a patient with antiphospholipid syndrome

Several clinical conditions, such as deep vein thrombosis, cerebral infarct, pulmonary infarct, skin ulcers, renal failure, and habitual abortion, are thought to be associated with the antiphospholipid syndrome. The authors describe a 32-year-old woman who had characteristics of the antiphospholipid syndrome including increased immunoglobulin G-cardiolipin antibody titers, iliofemoral vein thrombosis, pulmonary embolism, headache, visual disturbances, and habitual abortion. During hospitalization, she suddenly experienced right-sided weakness. A Tc-99m HMPAO brain scan showed the probability of a transient ischemic attack in the left frontotemporal cortex.

Iodothyronine sulfotransferase activity in rat uterus during gestation

In developing mammals, we and others demonstrated that sulfation is an important pathway in the metabolism of thyroid hormone, and there is significant fetal-maternal transfer of sulfated iodothyronine. In the present study, we characterized a novel iodothyronine sulfotransferase (IST) in pregnant rat uterus. (125)I-labeled 3,3'-diiodothyronine (T(2)), T(3), rT(3), and T(4) were used as substrates with unlabeled 3'-phosphoadenosine-5'-phosphosulfate (PAPS) as the sulfate donor. Sulfated iodothyronine products were separated by Sephadex LH-20 column and further identified on reverse phase HPLC. We measured IST activity in pregnant rat uterus by incubating 1 microM substrate, 50 microM PAPS, and 50 microg cytosol protein, pH 7.2, 30 min at 37 degrees C. The results show that the substrate preference of the uterine IST activity is: T(2 )> rT(3 )> T(3)> T(4); the pH optimum is 6.0 for T(2). The K(m) and V:(max) (for gestational day 21 uterus) for T(2) are 0.62 microM and 3466 pmol/mg protein/h, respectively; for PAPS the values are 2.6 microM and 1523 pmol/mg protein/h, respectively. During pregnancy, the total activities exhibit a U-shaped curve with minimum activity at day 13 of gestation; while a thermostable activity increases significantly near term. In summary, there is significant uterine IST that varies during pregnancy. The role of this uterine sulfotransferase activities in regulating the bioavailability of thyroid hormone in the developing fetus remains to be elucidated.

Krypton-81m ventilation and technetium-99m macroaggregated albumin perfusion scintigraphy for detection of pulmonary embolism: the first experience in Taiwan

BACKGROUND

This study was designed to assess whether the self-made (Institute of Nuclear Energy Research, Taiwan) krypton (Kr)-81m could be used as a ventilation agent to detect patients with suspected pulmonary embolism (PE). In addition, xenon (Xe)-133 ventilation scintigraphy was also performed for comparison.

METHODS

Forty patients with suspected PE were studied. Each patient received Kr-81m ventilation, Xe-133 ventilation and technetium (Tc)-99m macroaggregated albumin (MAA) perfusion studies on the same day. Images were judged using the criteria of the modified Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED). For those with a high or intermediate probability of PE on lung scans and normal pulmonary function tests, anticoagulants were given and patients were monitored with Tc-99m MAA perfusion studies after treatment. The final diagnosis was based on chest radiography, pulmonary function tests and lung scans.

RESULTS

All 40 patients successfully underwent lung scans. Of these, 11 had PE. Ten of the 11 cases were detected using Kr-81m ventilation and Tc-99m MAA perfusion studies, resulting in a sensitivity of 91%. Seven of 11 cases were detected using Xe-133 ventilation and Tc-99m MAA perfusion studies, resulting in a sensitivity of 64%. Of the 11 patients with PE, four had PE alone; Kr-81m and Xe-133 results agreed in three patients, but Kr-81m detected PE in the remaining patient. Of the remaining seven patients who suffered from PE with obstructive airway disease, Kr-81m and Xe-133 agreed in four, but Kr-81m detected PE in another two patients and one case was missed by both studies.

CONCLUSIONS

Self-made Kr-81m was safe and effective for ventilation scintigraphy in humans. When Kr-81m was used for the detection of PE, it was particularly advantageous when PE occurred in small areas of the lungs or when the patient with PE had concurrent obstructive airway disease.

Effects of temperature on radiochemical purity and immunoreactivity of radiolabeled monoclonal antibody 1H10

OBJECTIVE

This study was undertaken to investigate the effects of temperature on preserving the radiochemical purity and immunoreactivity of 125I- and 131I-labeled monoclonal antibody (MAb) 1H10--an antibody against human cervical carcinoma cell-surface antigen.

METHODS

An antibody-irrelevant human melanoma cell line, H2269, served as the control group. Iodine-125 and 131I radiolabeling of MAbs 1H10 and H2669 was performed by the chloramine-T method. All the prepared MAbs were divided into aliquots and stored at 4, -20, and -70 degrees C for 2-14 d. The radiochemical purity and immunoreactivity of the labeled antibodies in set conditions were measured by thin-layer chromatography and a modified index, respectively, after a single freeze-and-thaw cycle.

RESULTS

Reduced release of free radioiodide and better preservation of immunoreactivity were observed in the radiolabeled MAbs stored at -70 degrees C than in those stored at -20 degrees C or 4 degrees C. The extent of free iodide dissociation and immunologic binding degradation of 125I-labeled MAb 1H10 appeared milder than that of 131I-labeled MAb under the same conditions. However, both 125I- and 131I-labeled MAb stored at -70 degrees C or -20 degrees C retained more than 90% radiochemical purity for at least 3d.

CONCLUSION

Freezing provides an appropriate alternative for reducing radiolysis and preserving immunoreactivity of radioiodinated MAbs. MAb 1H10, labeled with either 125I or 131I and stored at temperatures of -20 degrees C or below for 3 d after labeling, appeared stable in both radiolabeling and binding studies in vitro and was still acceptable for in vivo use.

Adult intussusception: a 12-year experience, with emphasis on etiology and analysis of risk factors

BACKGROUND

To determine the incidence, causes, and associated risk factors of adult intussusception.

METHODS

Forty-five cases of adult intussusception proven by surgery were collected from 58,000 surgeries performed from December 1986 through December 1998. The condition leading to intussusception, imaging studies, and clinical risk factors were analyzed.

RESULTS

Nineteen men and 26 women, 18 to 83 years of age (mean, 52.6 years), experienced intussusception. The incidence of adult intussusception was 0.08% of abdominal surgeries and 3.0% of intestinal obstructions. A benign process was diagnosed in 25 cases (55.6%), malignancy in 16 cases (35.6%), surgery-related intussusception in 1 case (2.2%), and an idiopathic condition existed in 3 cases (6.6%). The major cause of adult intussusception due to benign lesions was polyps (12/25) and for malignancy, it was colonic adenocarcinoma (14/16). The diagnostic imaging rates were 52% for computed tomography, 41% for barium studies and 32% for abdominal ultrasound. There was no mortality due to intussusception; 4 patients (8.9%) died of colon cancer with liver metastasis. No definite risk factor was identified, but leukocytosis and a shorter preoperative duration tended to increase the risk of complications (p = 0.084, 0.082 respectively).

CONCLUSION

Malignancy was the major cause of colonic intussusception, as was a benign process the primary cause of intestinal intussusception. These adult patients with intussusception received adequate surgical care and had a good prognosis except for those with colon cancer and liver metastasis.

The role of lung scintigraphy in the diagnosis of nephrotic syndrome with pulmonary embolism

PURPOSE

Patients with nephrotic syndrome (NS) have an increased tendency to develop thrombosis and even to progress to pulmonary embolism (PE). This study was performed to determine the incidence of PE in NS with severe hypoalbuminemia and to investigate the possible role of ventilation-perfusion (V/Q) lung scans to evaluate these patients.

METHODS

Eighty-nine patients with NS (serum albumin concentration < 2 g/dl) and risk factors for PE were studied. In all patients, the probability that PE would develop was assessed based on the results of V/Q lung scans (Xe-133 for ventilation and Tc-99m MAA for perfusion imaging). The lung scans were judged using the modified Prospective Investigation of Pulmonary Embolism Diagnosis criteria. In 25 (28%) patients whose lung scans showed an intermediate or low probability, but for whom there was a strong clinical indication of PE, pulmonary angiography was performed. The patients' clinical symptoms and signs on initial examination were observed. Additional examinations included electrocardiograms, chest radiography, and hematochemical tests such as albumin, blood urea nitrogen, creatinine, cholesterol, triglycerides, fibrinogen, antithrombin III, prothrombin time, and activated partial thromboplastin time.

RESULTS

Based on the findings of lung scans, 19 (21%) of the patients were categorized as having a high probability of PE. However, pulmonary angiography found that 10 (11%) other patients had PE despite having lung scan findings categorized as intermediate or low probability of PE. Except for plasma fibrinogen and antithrombin III levels, neither the clinical symptoms and signs, electrocardiogram findings, chest radiograph results, nor values of hematochemical testing were consistent with the occurrence of PE in these 29 patients.

CONCLUSION

The results of this study suggest that PE is not a rare complication in patients with NS, and is usually clinically silent. In this series, the occurrence of PE did not appear to be always correlated with the clinical or hematochemical severity of NS, except for the association with elevated levels of fibrinogen and antithrombin III. When treating the clinical symptoms of patients with NS, physicians should be alert to the possible complication of PE. Serial V/Q lung scans may provide valuable clues in the evaluation of these patients.

Aortoduodenal fistula presenting as acute massive gastrointestinal bleeding and recurrent syncope: case report

Aortoenteric fistula is a rare condition that may cause death in patients due to gastrointestinal bleeding. The duodenum is the most frequently involved site, at 78.5% of 191 cases by Nagy and Marshall's meta-analysis. It is characterized by the clinical triad of abdominal pain, gastrointestinal bleeding, and an abdominal mass. Abdominal computed tomography is the most useful tool in detecting an aortoenteric fistula. To prevent a high mortality rate, early diagnosis is necessary. Exploratory laparotomy is required for patients who are highly suspected of having an aortoduodenal fistula. Herein, we report a 60-year-old man who suffered from acute gastrointestinal bleeding, recurrent syncope, and impending shock. Abdominal computed tomography revealed a 6 cm longitudinal aneurysm in the infrarenal aorta. Emergency laparotomy was performed and revealed an aortoduodenal fistula in the fourth portion of the duodenum causing acute duodenal bleeding. The patient survived and has undergone 2 years worth of regular follow-up in our outpatient department.

Synthesis and cytostatic properties of structure-simplified analogs of dolastatin 15

The linear peptide dolastatin 15 (1), a potent antineoplastic constituent from the shell-less mollusk Dolabella auricularia, has been selected as the lead compound for developing novel antitumor drugs. Recently LU103793 (2), a synthetic and structure-simplified analog of dolastatin 15, has been demonstrated to be highly cytotoxic [IC50 = 0.1 nM; M. De Arruda, C.A. Cocchiaro, C.M. Nelson, C. M. Grinnel, B. Janssen, A. Haupt & T. Barlozzari (1995) Cancer Res. 55, 3085-3092]. Both compounds have been undergoing human cancer clinical trials in Europe and North America. Based on the novel structure of LU103793, a series of analogs modified at the N-terminal dolavalyl moiety and -Pro-Pro-benzylamide unit was developed. These synthesized analogs were tested using a sulforhodamine B (SRB) assay for the drug-screening program at NCI on a variety of human cancer cell lines. As expected, most analogs exhibited potent and selective growth inhibition against leukemia. Analog 18 was specifically active against HL-60 and K-562 cell lines (GI50s: 0.05 microM and 0.07 microM, respectively) while analogs 14 and 17 were selectively potent against prostate and breast cancer cell lines (GI50s at micromolar levels). However, all analogs were less potent than 2 as growth inhibitors of some breast and colon cancer cell lines (e.g. MDA-MB-435 and HT-29). We believe that modification of novel marine natural products as synthetic analogs might show particular promise for developing novel anticancer candidates with moderate specificity.

Fetal-to-maternal transfer of 3,3',5-triiodothyronine sulfate and its metabolite in sheep

Earlier studies have shown that sulfoconjugation is a major pathway of thyroid hormone metabolism in fetal mammals. To assess the placental transfer of sulfoconjugates in the pregnant sheep model, we measured 3,3',5-triiodothyronine (T(3)) sulfate (T(3)S), 3, 3'-diiodothyronine sulfate (T(2)S), and T(3) concentrations in fetal serum and in maternal serum and urine after T(3)S infusion to the fetus (n = 5) or the ewe (n = 6). Maternal infusion of T(3)S did not increase fetal serum T(2)S, T(3)S, or T(3) concentrations. In contrast, fetal infusion of T(3)S produced significant increases in maternal serum T(2)S and T(3)S but not T(3) concentrations. Fetal T(3)S infusion also increased maternal urine excretion of T(3)S. However, the 4-h cumulative maternal urinary excretion of T(2)S and T(3)S after fetal T(3)S infusion was less than the excretion observed after fetal infusion of equimolar amounts of T(3) in our previous study. It is concluded that fetal serum T(2)S and T(3)S can be transferred to maternal compartments. However, compared with T(3), these sulfoconjugates may be less readily transferred.

A T2S cross-reactive material (compound W) in hyperthyroid patients with trophoblastic disease

In a previous study we observed increased serum levels of a 3,3'-diiodothyronine sulfate (T2S)-like material (compound W) in women who received human chorionic gonadotropin (hCG) treatment. In the present study we assessed serum compound W values in 113 women (total serum sample: 190) with trophoblastic disease, in 7 normal nonpregnant women during the menstrual cycle and 7 women given hCG treatment in the course of in vitro fertilization. Fifty-three women with trophoblastic disease had serum free thyroxine (FT4) concentrations greater than 3.0 ng/dL with suppressed serum thyrotropin (TSH) levels; 61 had FT4 values less than 3.0 ng/dL with a mean TSH of 0.83 mU/L. Mean (+/- SE) compound W concentrations in the high FT4 group were significantly higher than in the low FT4 group (76 +/- 8.1 vs. 21 +/- 1.7 ng T2S equivalent, p < 0.001) There were significant correlations between serum hCG and compound W concentrations (r = 0.472, p < 0.001), serum FT4 and hCG (r = 0.503, p < 0.0001) and serum FT4 and compound W (r = 0.585, p < 0.0001). In nonpregnant women serum compound W levels increased from 7.5 +/- 8 ng/dL at the end of the menstrual period to 15 +/- 1.7 ng/dL 21 days after the last menstrual period. Finally, a single dose of hCG (10,000 USP units, intramuscularly) increased mean (+/- SE) serum compound W levels from 12.8 +/- 2.3 to 64 +/- 9.7 ng/dL and 54 +/- 12 ng/dL at 9 and 16 days, respectively. These results indicate that hCG and perhaps luteinizing hormone (LH) increase serum compound W concentrations in women. The mechanism and significance presently are unclear.

Ileal aberrant pancreas induces intussusception and gastrointestinal bleeding in an adult woman--case report

Aberrant pancreas is a congenital anomaly. In surgical series, its incidence varied from 0.2 to 0.8%. About 70% of aberrant pancreas occur in the gastrointestinal tract. Eighty percent of them locate in the stomach and duodenum, and only 0.2% in the ileum. We report on a 25-year-old woman with ileal aberrant pancreas who suffered from ileal intussusception and recurrent gastrointestinal bleeding. The diagnosis was confirmed by surgery and histology. She is symptom-free after surgery.

Retrospective analysis of 196 patients with suspected pulmonary thromboembolism

BACKGROUND

There has not been a statistical analysis reporting on patients with pulmonary thromboembolism (PE) in Taiwan. To identify the most common manifestations in patients with PE in Taiwan, we conducted this retrospective study.

METHODS

We collected and analyzed the medical records of 196 patients (53 men, mean age, 60 years; 143 women, mean age, 46 years) whose clinical symptoms and signs, chest radiographs and lung scan findings were suggestive of PE. Conventional chest radiography was performed 24 hours to 48 hours before lung scans. The radiopharmaceuticals used in lung scans were 133Xenon for ventilation studies and 99mTechnetium macroaggregated albumin for perfusion studies. All patients had received anticoagulant therapy (heparin and coumadin) to improve PE.

RESULTS

The two most common symptoms and signs of PE in the 196 patients were dyspnea (172/196, 87.8%) and tachypnea (176/196, 89.8%). The most common abnormal finding on chest radiography was increased lung markings, which were present in about 36.7% (72/196) of patients. Lung scans showed two or more, large, mismatched, segmental defects (high probability of PE) in both lungs in about 88.8% (174/196) of patients. After anticoagulant therapy, PE, as seen on lung scans, was resolved within four weeks in approximately 93.9% (184/196) of patients.

CONCLUSIONS

In Taiwan, a woman aged 40 to 50 years, with no prior history of other medical problems or surgical procedures, with sudden onset of dyspnea or tachypnea, normal or increased lung markings on chest radiography and two or more large mismatched segmental defects on lung scans, is at greatest risk of developing PE. Most patients with PE showed a good response to anticoagulant therapy within four weeks.

Hepatocellular carcinoma presenting with acquired porphyria: a case report and review of the literature

Hepatocellular carcinoma (HCC) with acquired porphyria is a very rare condition. It is characterized variably by hyperpigmentation, skin fragility and photodistributed subepidermal vesicles. The serum, urine and/or stool porphyrin levels, usually markedly elevated, can change according to the clinical course. We report here a case of hepatocellular carcinoma presenting with a paraneoplastic syndrome of acquired porphyria. A 73-year-old Chinese woman had the characteristic facial pigmentation of cutaneous porphyria and histologically proven hepatocellular carcinoma. Her serum zinc protoporphyrin was elevated and her urine tested positive for coproporphyrin. Her protoporphyrin and alpha-fetoprotein levels dropped after transarterial chemoembolization treatment. Acquired porphyria in hepatocellular carcinoma occurs exclusively in older persons with huge hepatocellular carcinoma and/or cirrhosis. Before diagnosis, it must be carefully differentiated from inherent porphyrias with HCC, and porphyrias induced by drugs or heavy metal intoxication must be ruled out.

Urinary compound W in pregnant women is a potential marker for fetal thyroid function

OBJECTIVE

Previously we reported 3,3'-diiodothyronine sulfate-like material (compound W) in maternal serum, and studies suggest that compound W is derived from thyroid hormones of fetal origin. In this study we characterized gestational changes of urinary compound W concentrations to correlate with changes in serum concentrations.

STUDY DESIGN

Urinary samples were collected from 94 women at various gestational ages ranging from 3 to 40 weeks. Urinary compound W was first identified biochemically. The concentrations of compound W (adjusted for creatinine levels) were assessed by a 3,3'-diiodothyronine sulfate radioimmunoassay in ethanol extracts of urine samples.

RESULTS

Compound W increased to 88 +/- 1.4 pmol (of 3,3'-diiodothyronine sulfate equivalent)/mmol creatinine in urinary samples obtained from 26 women in the first trimester of pregnancy compared with 40 +/- 6.9 pmol/mmol creatinine in 10 nonpregnant women. Excretion of compound W increased further during the second and third trimesters: 171 +/- 17 (n = 18) and 434 +/- 26 (n = 50) respectively. In contrast, urinary 3,3',5-triiodothyronine sulfate concentrations measured by radioimmunoassay were similar during pregnancy to values in nonpregnant women.

CONCLUSIONS

Urinary compound W concentrations increase with the progression of normal pregnancy and correlate with the increase in serum levels. Random spot urine compound W concentrations, adjusted for creatinine levels, may be used in place of serum levels in conditions in which obtaining serum samples may be technically difficult, especially during population screening.