The role of APOBEC3B in lung tumor evolution and targeted cancer therapy resistance

In this study, the impact of the apolipoprotein B mRNA-editing catalytic subunit-like (APOBEC) enzyme APOBEC3B (A3B) on epidermal growth factor receptor (EGFR)-driven lung cancer was assessed. A3B expression in EGFR mutant (EGFRmut) non-small-cell lung cancer (NSCLC) mouse models constrained tumorigenesis, while A3B expression in tumors treated with EGFR-targeted cancer therapy was associated with treatment resistance. Analyses of human NSCLC models treated with EGFR-targeted therapy showed upregulation of A3B and revealed therapy-induced activation of nuclear factor kappa B (NF-κB) as an inducer of A3B expression. Significantly reduced viability was observed with A3B deficiency, and A3B was required for the enrichment of APOBEC mutation signatures, in targeted therapy-treated human NSCLC preclinical models. Upregulation of A3B was confirmed in patients with NSCLC treated with EGFR-targeted therapy. This study uncovers the multifaceted roles of A3B in NSCLC and identifies A3B as a potential target for more durable responses to targeted cancer therapy.

[Bioinformatics analysis of primary biliary cholangitis key genes and molecular mechanisms]

Objective: To extract the differentially expressed key genes of primary biliary cholangitis (PBC) using bioinformatics methods, so as to provide information for further study into the mechanism. Methods: The GSE119600 dataset was downloaded from the GEO database to obtain differentially expressed genes. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed for differentially expressed genes. Protein-protein interaction (PPI) network reconstruction, Cytoscape software visualization, and core gene screening were performed. The area under the receiver operating characteristic curve (ROC AUC) was used to assess the diagnostic effectiveness of genes and plot the pROC software package. The x-Cell software was used to calculate the enrichment score of 34 immune cells in each sample. Finally, four key genes (PSMA4, PSMA1, PSMB1, and PSMA3) were selected. Blood samples were analyzed using the qPCR method. Results:: A total of 373 immune-related differentially expressed genes were identified. Eight genes (PSMC6, PSMB2, PSMB1, PSMA3, PSMA4, PSMA1, PSMD7, and PSMB5) were screened from the 178 nodes and 596 edges as hub genes of the PPI network, which were significantly related to amino acid metabolism, hematopoietic stem cell differentiation, cell cycle, and immune processes. PSMA4, PSMA1, PSMB1, and PSMA3 were defined as immunological biomarkers for PBC with an AUC value of the ROC curve > 0.7. Immunoinfiltrating cell analysis showed that the proportion of eosinophils was significantly higher in PBC patients compared to the control group, whereas the proportion of CD4+ memory T cells, plasma cells, Th2 cells, and cDC cells was significantly lower in PBC patients than the control group. Plasma cells were associated with all four immunological biomarkers. Seven PBC patients and seven healthy subjects were selected for peripheral blood qPCR validation, which demonstrates that PSMB1, PSMA3, PSMA1, and PSMA4 levels were significantly lower in PBC patients than healthy subjects, with a statistically significant difference. Conclusion:: Bioinformatics screened eight key genes, of which four were key immunological markers and may serve as a basis for clinical diagnosis and mechanism exploration.

DDX17 is required for efficient DSB repair at DNA:RNA hybrid deficient loci

Proteins with RNA-binding activity are increasingly being implicated in DNA damage responses (DDR). Additionally, DNA:RNA-hybrids are rapidly generated around DNA double-strand breaks (DSBs), and are essential for effective repair. Here, using a meta-analysis of proteomic data, we identify novel DNA repair proteins and characterise a novel role for DDX17 in DNA repair. We found DDX17 to be required for both cell survival and DNA repair in response to numerous agents that induce DSBs. Analysis of DSB repair factor recruitment to damage sites suggested a role for DDX17 early in the DSB ubiquitin cascade. Genome-wide mapping of R-loops revealed that while DDX17 promotes the formation of DNA:RNA-hybrids around DSB sites, this role is specific to loci that have low levels of pre-existing hybrids. We propose that DDX17 facilitates DSB repair at loci that are inefficient at forming DNA:RNA-hybrids by catalysing the formation of DSB-induced hybrids, thereby allowing propagation of the damage response.

Comparison of portal and capsular microscopic vascular invasion in the outcomes of early HCC after curative resection

Microscopic vascular invasion (MVI) is a strong risk factor associated with tumor recurrence and poor overall survival (OS) among hepatocellular carcinoma (HCC) patients after resection. Two types of MVI are identified: portal vein and capsular vein invasion. However, little is known about the impact of different types of MVI on HCC recurrence. The present study aimed to compare HCC recurrence and OS between the portal vein and capsule vein MVI. Patients with Barcelona Clinic Liver Cancer (BCLC) stage 0 or A HCC who underwent primary resection between January 2001 and June 2016 were consecutively recruited. Factors that influenced OS and recurrence-free survival (RFS) were analyzed using Cox proportional hazards models. Of the 857 eligible patients, 327 (38.2%) had MVI, and 530 (61.8%) were without MVI. Of the 327 patients with MVI, 85 (26.0%) were with portal vein, 178 (54.4%) with capsular vein, and 64 (19.6%) with both-MVI type. Patients with both-MVI type suffered from a higher proportion of BCLC stage A (P < 0.001), capsular invasion (P = 0.002), and satellite nodules (P < 0.001). Both-MVI type is an independent risk factor for HCC recurrence (hazard ratio [HR]: 1.69; 95% CI, 1.22-2.36, P = 0.002) and mortality (HR: 2.29; 95% CI, 1.59-3.29, P < 0.001) compared with non-MVI. We further found that both-MVI type was significantly associated with a higher risk of extrahepatic recurrence (EHR) (HR: 8.74; 95% CI, 2.38-32.03, P = 0.001). Among HCC patients after curative resection, concurrent portal and capsular MVI is a risk factor for HCC recurrence, especially for EHR, in comparison with non-MVI or only portal or capsular MVI alone.

Induction of APOBEC3 Exacerbates DNA Replication Stress and Chromosomal Instability in Early Breast and Lung Cancer Evolution

APOBEC3 enzymes are cytosine deaminases implicated in cancer. Precisely when APOBEC3 expression is induced during cancer development remains to be defined. Here we show that specific APOBEC3 genes are upregulated in breast ductal carcinoma in situ, and in preinvasive lung cancer lesions coincident with cellular proliferation. We observe evidence of APOBEC3-mediated subclonal mutagenesis propagated from TRACERx preinvasive to invasive non-small cell lung cancer (NSCLC) lesions. We find that APOBEC3B exacerbates DNA replication stress and chromosomal instability through incomplete replication of genomic DNA, manifested by accumulation of mitotic ultrafine bridges and 53BP1 nuclear bodies in the G1 phase of the cell cycle. Analysis of TRACERx NSCLC clinical samples and mouse lung cancer models revealed APOBEC3B expression driving replication stress and chromosome missegregation. We propose that APOBEC3 is functionally implicated in the onset of chromosomal instability and somatic mutational heterogeneity in preinvasive disease, providing fuel for selection early in cancer evolution. SIGNIFICANCE: This study reveals the dynamics and drivers of APOBEC3 gene expression in preinvasive disease and the exacerbation of cellular diversity by APOBEC3B through DNA replication stress to promote chromosomal instability early in cancer evolution.This article is highlighted in the In This Issue feature, p. 2355.

SARS-CoV-2 detection by a clinical diagnostic RT-LAMP assay

The ongoing pandemic of SARS-CoV-2 calls for rapid and cost-effective methods to accurately identify infected individuals. The vast majority of patient samples is assessed for viral RNA presence by RT-qPCR. Our biomedical research institute, in collaboration between partner hospitals and an accredited clinical diagnostic laboratory, established a diagnostic testing pipeline that has reported on more than 252,000 RT-qPCR results since its commencement at the beginning of April 2020. However, due to ongoing demand and competition for critical resources, alternative testing strategies were sought. In this work, we present a clinically-validated procedure for high-throughput SARS-CoV-2 detection by RT-LAMP that is robust, reliable, repeatable, specific, and inexpensive.

SARS-CoV-2 detection by a clinical diagnostic RT-LAMP assay

The ongoing pandemic of SARS-CoV-2 calls for rapid and cost-effective methods to accurately identify infected individuals. The vast majority of patient samples is assessed for viral RNA presence by RT-qPCR. Our biomedical research institute, in collaboration between partner hospitals and an accredited clinical diagnostic laboratory, established a diagnostic testing pipeline that has reported on more than 252,000 RT-qPCR results since its commencement at the beginning of April 2020. However, due to ongoing demand and competition for critical resources, alternative testing strategies were sought. In this work, we present a clinically-validated procedure for high-throughput SARS-CoV-2 detection by RT-LAMP in 25 minutes that is robust, reliable, repeatable, sensitive, specific, and inexpensive.

Author Correction: Scalable and robust SARS-CoV-2 testing in an academic center

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Assessing adaptation measures on agricultural water productivity under climate change: A case study of Huai River Basin, China

This study explored an integrated framework to assess the effectiveness of adaptation measures on the water productivity (WP) of the agricultural water management (AWM) system in the Huai river basin of China considering climate change impact. The adaptation measures include optimization of cropping pattern (OCP) and upgradation of irrigation techniques (UIT). The delta change method was used to downscale the climate variables from RCP4.5 and RCP8.5 of general circulation models (GCMs) during 2021-2050, the water footprint theory was used to estimate the spatial distribution of blue water to calculate the WP, and the nonlinear optimization model was used to seek optimal cropping pattern aiming at maximizing the system's WP. The changes in WP due to climate change and adaptation measures (e.g. combinations of OCP and UIT) were compared. Results indicated that WP under RCP4.5 and RCP8.5 would be 4.56% and 6.51% lower than those under the benchmark scenario, respectively. The mitigation rates to the negative impact of climate change on WP under RCP4.5 and RCP8.5 would be (1) 3.05% and 3.37% for the combination of spay irrigation technique and OCP, and (2) 4.34% and 4.59% for the combination of drip irrigation technique and OCP, respectively. It was revealed that the combination of drip irrigation and cropping pattern optimization could largely offset the adverse effect from climate change on WP under RCP4.5. Under such a scenario, the total plant areas of wheat and maize would reduce over the basin and so would the net export of crops in the basin; this would lead to a decrease in the crop trade benefit of 7.07 × 10⁹ $ and a relief of 7.50 × 10⁹ m³ of blue water loss. This study results could offer strategic decision support for long-term sustainable AWM of Huai river basin in a changing environment.

Controllable valley filter in graphene topological line defect with magnetic field

The extended line defect of graphene is an extraordinary candidate in valleytronics while the high valley polarization can only occur for electrons with high incidence angles which brings about tremendous challenges to experimental realization. In this paper, we propose a novel quantum mechanism to filter one conical valley state in the line defect of graphene by applying a local magnetic field. It is found that due to the movement of the Dirac points, the transmission profiles of the two valleys are shifted along the injection-angle axis at the same pace, resulting in the peak transmission of one valley state being reduced drastically while remaining unaffected for the other valley state, which induces nearly perfect valley polarization. The valley polarization effect can occur for all the incident angle and plays a key role in graphene valleytronics.

eIF4A2 drives repression of translation at initiation by Ccr4-Not through purine-rich motifs in the 5'UTR

BACKGROUND

Regulation of the mRNA life cycle is central to gene expression control and determination of cell fate. miRNAs represent a critical mRNA regulatory mechanism, but despite decades of research, their mode of action is still not fully understood.

RESULTS

Here, we show that eIF4A2 is a major effector of the repressive miRNA pathway functioning via the Ccr4-Not complex. We demonstrate that while DDX6 interacts with Ccr4-Not, its effects in the mechanism are not as pronounced. Through its interaction with the Ccr4-Not complex, eIF4A2 represses mRNAs at translation initiation. We show evidence that native eIF4A2 has similar RNA selectivity to chemically inhibited eIF4A1. eIF4A2 exerts its repressive effect by binding purine-rich motifs which are enriched in the 5'UTR of target mRNAs directly upstream of the AUG start codon.

CONCLUSIONS

Our data support a model whereby purine motifs towards the 3' end of the 5'UTR are associated with increased ribosome occupancy and possible uORF activation upon eIF4A2 binding.

Drosha drives the formation of DNA:RNA hybrids around DNA break sites to facilitate DNA repair

The error-free and efficient repair of DNA double-stranded breaks (DSBs) is extremely important for cell survival. RNA has been implicated in the resolution of DNA damage but the mechanism remains poorly understood. Here, we show that miRNA biogenesis enzymes, Drosha and Dicer, control the recruitment of repair factors from multiple pathways to sites of damage. Depletion of Drosha significantly reduces DNA repair by both homologous recombination (HR) and non-homologous end joining (NHEJ). Drosha is required within minutes of break induction, suggesting a central and early role for RNA processing in DNA repair. Sequencing of DNA:RNA hybrids reveals RNA invasion around DNA break sites in a Drosha-dependent manner. Removal of the RNA component of these structures results in impaired repair. These results show how RNA can be a direct and critical mediator of DNA damage repair in human cells.

Human 4E-T represses translation of bound mRNAs and enhances microRNA-mediated silencing

A key player in translation initiation is eIF4E, the mRNA 5' cap-binding protein. 4E-Transporter (4E-T) is a recently characterized eIF4E-binding protein, which regulates specific mRNAs in several developmental model systems. Here, we first investigated the role of its enrichment in P-bodies and eIF4E-binding in translational regulation in mammalian cells. Identification of the conserved C-terminal sequences that target 4E-T to P-bodies was enabled by comparison of vertebrate proteins with homologues in Drosophila (Cup and CG32016) and Caenorhabditis elegans by sequence and cellular distribution. In tether function assays, 4E-T represses bound mRNA translation, in a manner independent of these localization sequences, or of endogenous P-bodies. Quantitative polymerase chain reaction and northern blot analysis verified that bound mRNA remained intact and polyadenylated. Ectopic 4E-T reduces translation globally in a manner dependent on eIF4E binding its consensus Y30X4L site. In contrast, tethered 4E-T continued to repress translation when eIF4E-binding was prevented by mutagenesis of YX4L, and modestly enhanced the decay of bound mRNA, compared with wild-type 4E-T, mediated by increased binding of CNOT1/7 deadenylase subunits. As depleting 4E-T from HeLa cells increased steady-state translation, in part due to relief of microRNA-mediated silencing, this work demonstrates the conserved yet unconventional mechanism of 4E-T silencing of particular subsets of mRNAs.

Translational repression and eIF4A2 activity are critical for microRNA-mediated gene regulation

MicroRNAs (miRNAs) control gene expression through both translational repression and degradation of target messenger RNAs (mRNAs). However, the interplay between these processes and the precise molecular mechanisms involved remain unclear. Here, we show that translational inhibition is the primary event required for mRNA degradation. Translational inhibition depends on miRNAs impairing the function of the eIF4F initiation complex. We define the RNA helicase eIF4A2 as the key factor of eIF4F through which miRNAs function. We uncover a correlation between the presence of miRNA target sites in the 3' untranslated region (3'UTR) of mRNAs and secondary structure in the 5'UTR and show that mRNAs with unstructured 5'UTRs are refractory to miRNA repression. These data support a linear model for miRNA-mediated gene regulation in which translational repression via eIF4A2 is required first, followed by mRNA destabilization.

Imaging with subwavelength resolution by a generalized superlens at infrared wavelengths

We demonstrate experimentally negative refraction by a photonic crystal prism and imaging of a point source by a photonic crystal slab at 1.5 microm wavelength. The photonic crystal structures were nanofabricated in a InGaAsP/InP heterostructure platform, and optical characterization was performed using a near-field scanning optical microscope. By designing a suitable lens surface termination, an image spot size of 0.12lambda2 was achieved, demonstrating superlens imaging with subwavelength resolution well below Abbe's diffraction limit (0.5lambda2).

Efficacy of Shuanghu liver-clearing granule in prevention and treatment of carbon tetrachloride-induced hepatic fibrosis in rats

AIM: To investigate the effects of Shuanghu liver-clearing granule on prevention and treatment of carbon tetrachloride-induced hepatic fibrosis in rats.

METHODS: Sixty Sprague-Dawley rats were divided into 6 groups, namely normal control group (group A), model group (group B), Shuanghu liver-clearing granule small-, middle-, large-dose groups (group C1, C2, C3) and silymarin control group (group D). The rats in group B, group C1, C2, C3 and group D were subcutaneously administrated with carbon tetrachloride for 8 wk. Then the rats in group C1, C2, C3 were administered with Shuanghu liver-clearing granule at different doses for 8 wk. The rats in group D were then administered with silymarin. The levels of serum HA, ⅣC, PⅢP of all rats were measured respectively under the same condition and at the same time. The pathological changes of hepatic fibrosis and the density of collagen in liver specimens of all rats were assessed using HE and Masson staining.

RESULTS: Compared with group B, lipid vacuoles and liver necrosis were significantly reduced, and false lobular formation of collagen deposition was significantly decreased in group C3 and D. There was fibrosis difference between group C1, C2, C3 and group D (12.6 ± 4.6, 10.7 ± 3.9, 6.4 ± 3.4, 6.5 ± 3.3 vs 16.1 ± 5.5, all P < 0.05). Serum HA and PⅢP levels were lower in group C3, D than in group B (161.50 ± 37.38, 185.30 ± 9.76 vs 292.25 ± 72.99; 18.55 ± 2.27, 17.60 ± 2.54 vs 33.42 ± 6.49; 19.49 ± 3.26, 25.84 ± 4.69 vs 36.58 ± 8.13, P < 0.001 or 0.05).

CONCLUSION: Shuanghu liver-clearing granule has obvious therapeutic and preventive effects on carbon tetrachloride-induced hepatic fibrosis with a dose-effect relationship in rats.

A new mechanism for negative refraction and focusing using selective diffraction from surface corrugation

Refraction at a smooth interface is accompanied by momentum transfer normal to the interface. We show that corrugating an initially smooth, totally reflecting, non-metallic interface provides a momentum kick parallel to the surface, which can be used to refract light negatively or positively. This new mechanism of negative refraction is demonstrated by visible light and microwave experiments on grisms (grating-prisms). Single-beam all-angle-negative-refraction is achieved by incorporating a surface grating on a flat multilayered material. This negative refraction mechanism is used to create a new optical device, a grating lens. A planoconcave grating lens is demonstrated to focus plane microwaves to a point image. These results show that customized surface engineering can be used to achieve negative refraction even though the bulk material has positive refractive index. The surface periodicity provides a tunable parameter to control beam propagation leading to novel optical and microwave devices.

Duality between quantum and classical dynamics for integrable billiards

We establish a duality between the quantum wave vector spectrum and the eigenmodes of the classical Liouvillian dynamics for integrable billiards. Signatures of the classical eigenmodes appear as peaks in the correlation function of the quantum wave vector spectrum. A semiclassical derivation and numerical calculations are presented in support of the results. These classical eigenmodes can be observed in physical experiments through the autocorrelation of the transmission coefficient of waves in quantum billiards. Exact classical trace formulas of the resolvent are derived for the rectangle, equilateral triangle, and circle billiards. We also establish a correspondence between the classical periodic orbit length spectrum and the quantum spectrum for integrable polygonal billiards.

Soluble kagome Ising model in a magnetic field

An Ising model on the kagome lattice with super-exchange interactions is solved exactly under the presence of a nonzero external magnetic field. The model generalizes the super-exchange model introduced by Fisher in 1960 and is analyzed in light of a free-fermion model. We deduce the critical condition and present detailed analyses of its thermodynamic and magnetic properties. The system is found to exhibit a second-order transition with logarithmic singularities at criticality.

Negative refraction and left-handed electromagnetism in microwave photonic crystals

We demonstrate the negative refraction of microwaves in a metallic photonic crystal prism. The spectral response of the photonic crystal prism, which manifests both positive and negative refraction, is in complete agreement with band-structure calculations and numerical simulations. The validity of Snell's law with a negative refractive index is confirmed experimentally and theoretically. The negative refraction observed corresponds to left-handed electromagnetism that arises due to the dispersion characteristics of waves in a periodic medium. This mechanism for negative refraction is different from that in metamaterials.

Refraction of electromagnetic energy for wave packets incident on a negative-index medium is always negative

We analyze refraction of electromagnetic wave packets on passing from an isotropic positive to an isotropic negative-refractive-index medium. We definitively show that in all cases the energy is always refracted negatively. For localized wave packets, the group refraction is also always negative.

Fractal Weyl laws for chaotic open systems

We present a conjecture relating the density of quantum resonances for an open chaotic system to the fractal dimension of the associated classical repeller. Mathematical arguments justifying this conjecture are discussed. Numerical evidence based on computation of resonances of systems of n disks on a plane are presented supporting this conjecture. The result generalizes the Weyl law for the density of states of a closed system to chaotic open systems.

Reduction in primary nonfunction of syngeneic islet transplants with nordihydroguaiaretic acid, a lipoxygenase inhibitor

To study the effectiveness of a lipoxygenase inhibitor, nordihydroguaiaretic acid (NDGA), in the reduction of primary nonfunction, an insufficient number of syngeneic islets were transplanted underneath the renal capsule with NDGA administered daily for 4 weeks. After transplantation of the 150 islets, the decrement of blood glucose levels was significantly faster in the mice that had received NDGA than in the mice that had received no drug at all or dimethyl sulfoxide (DMSO) (p < 0.005, p < 0.05). The mean duration of temporary posttransplant hyperglycemia was 22.3 +/- 3.2 (n = 10), 35.9 +/- 2.3 (n = 14), and 33.7 +/- 4.1 (n = 6) days for the respective groups. The diabetic mice that received 300 islets had their blood glucose levels decrease faster than those that received 150 islets (19.7 +/- 1.6 vs. 35.9 +/- 2.3 days, n = 14. p < 0.0001). There was no significant difference in the blood glucose reducing effect between the mice that received 150 islets with NDGA and the mice that received 300 islets [22.3 +/- 3.2 (n = 10) vs. 19.7 +/- 1.6 (n = 14) days, p > 0.05]. The insulin content of the graft from the mice treated with 150 islets and NDGA (3.02 +/- 0.24 microg, n = 4) was higher than that from the mice that received 150 islets but no treatment (1.10 +/- 0.26 microg, n = 15, p < 0.005) or that had been treated with DMSO (1.21 +/- 0.30 microg, n = 4, p <0.05). The insulin content of the pancreas remnant had no significant differences among the three groups. The net glucose-stimulated insulin secretion was 0.82 +/- 0.14 vs. 0.20 +/- 0.10 microIU/islet x 60 min (n = 8, p < 0.005) and 0.59 +/- 0.08 vs. 0.04 +/- 0.02 microIU/islet x 60 min (n = 8, p < 0.0001) for islets cultured without NDGA vs. with NDGA at 1 and 2 weeks, respectively. However, the insulin content of the cultured islets was similar between the two groups for up to 2 weeks of incubation (at 1 week: 0.71 +/- 0.01 vs. 0.67 +/- 0.04 ng/islet, n = 8, p > 0.05; at 2 weeks: 0.71 +/- 0.02 vs. 0.80 +/- 0.07 ng/islet, n = 8, p > 0.05). Serum leukotriene B4 (LTB4) concentrations before and between the fifth and seventh days after transplantation were determined. For diabetic mice that received 150 islets, serum LTB4 levels were 25,835 +/- 3,335 and 27,631 +/- 3,136 pg/ml (n = 4, p > 0.05). For diabetic mice that received 150 islets and NDGA, the corresponding figures were 22,401 +/- 2,706 pg/ml and 27,530 +/- 2,190 pg/ml (n = 8, p > 0.05). The graft histology revealed viable islet cells and networks of close vascular structures around the islets and did not reveal microscopic differences among the samples of all four groups. In conclusion, our data revealed that daily administration of NDGA for 4 weeks enhanced isoislet engraftment and preserved three times more mass of the islet beta cells in the isografts. This result indicates that NDGA reduces primary nonfunction of islet syngeneic grafts in diabetic mice.

Ising model on nonorientable surfaces: exact solution for the Möbius strip and the Klein bottle

Closed-form expressions are obtained for the partition function of the Ising model on an MxN simple-quartic lattice embedded on a Möbius strip and a Klein bottle. The solutions all lead to the same bulk free energy, but for finite M and N the expressions are different depending on whether the strip width M is odd or even. Finite-size corrections at criticality are analyzed and compared with those under cylindrical and toroidal boundary conditions. Our results are consistent with the conformal field prediction of a central charge c=1/2, provided that the twisted Möbius boundary condition is regarded as a free or fixed boundary.

Identification of familial hypercholesterolemia in Taiwan: report of eleven cases

BACKGROUND

Familial hypercholesterolemia is associated with a very high risk of premature coronary heart disease. In order to identify cases of familial hypercholesterolemia in Taiwan, we screened the hyperlipidemic patients in our metabolic clinics.

METHODS

Hyperlipidemic patients were screened in the metabolic outpatient department and the cases which fulfilled the clinical criteria of definitive or possible familial hypercholesterolemia were further analyzed. Their clinical characteristics, including age, gender, physical findings, past history of coronary heart disease or cerebrovascular accident (CVA), family history, and lipid profiles before and after medical treatment, were reviewed.

RESULTS

Eight women and 3 men fulfilled the diagnostic criteria. The mean age at diagnosis was 51.1 +/- 11.9 years old. Tendon xanthomas were found in 5 patients with definitive familial hypercholesterolemia. Coronary heart disease was confirmed in one patient and old CVA was noted in another 2 patients. The mean total cholesterol level was 390.3 +/- 88.9 mg/dl and the mean low density lipoprotein-cholesterol (LDL-cholesterol) level was 309.6 +/- 89.9 mg/dl before treatment. After a mean treatment duration of 45.2 months, the mean total cholesterol level and LDL-cholesterol level were 326.8 +/- 87.8 mg/dl and 249.1 +/- 91.1 mg/dl, respectively.

CONCLUSION

Clinically diagnosed familial hypercholesterolemia indeed exists in Taiwan. As compared to other reports, the mean age at diagnosis in our series was older and the majority of patients were women. Most patients were not vigorously treated and the family members were not thoroughly screened. Adequate treatment of patients with familial hypercholesterolemia in clinical practice and screening their family members are crucial in preventing new or recurrent coronary heart disease.

Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma

Radioactive iodine (131I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. 201Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative 131I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of 201Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of 131I and 201Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative 201Tl and 131I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. 201Tl imaging was performed before the 131I studies. Of the 62 patients who underwent 201Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the 201Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic 131I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by 201Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative 201Tl scans, 11 had positive findings on 131I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on 131I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative 201Tl and 131I scans, 15 had elevated serum Tg levels. Among these, local recurrence followed by lung metastases was manifested in a 49-year-old male with papillary thyroid carcinoma. In conclusion, both 131I and 201Tl scans are useful in the detection of recurrence or distant metastasis of well differentiated thyroid cancers. 201Tl scan could in particular be used in patients with a negative 131I scan in conjunction with an elevated Tg level.

Does surgery improve the survival of patients with advanced anaplastic thyroid carcinoma?

Anaplastic thyroid carcinoma is one of the most lethal neoplasms, with poor prognosis being reported by most authors. The benefits of surgery for most cases of advanced disease remain controversial. In this study we asked the following question: Does surgical intervention alter outcomes for patients with advanced anaplastic thyroid carcinoma? Forty-six patients with advanced anaplastic thyroid carcinoma were analyzed. There were 20 patients with advanced localized disease (group 1), 15 of whom received surgery. Of the other 26 patients with evidence of distant metastases (group 2), 13 received surgery. For group 1 patients, the mean survival was 12.8 months versus 8.6 months in the surgical and nonsurgical subgroups (p = 0.46). For group 2 patients, the mean survival was 3.5 months versus 2.8 months in the surgical and nonsurgical subgroups (p = 0.72). These data suggest that surgery does not improve survival for patients with advanced anaplastic thyroid carcinoma. In conclusion, the mean survival showed no significant differences between surgical and nonsurgical patients (p = 0.43). This study suggests that surgical resection does not improve the survival of patients with advanced anaplastic thyroid carcinoma.

Factors affecting postoperative fecal soiling in Hirschsprung's disease

We retrospectively assessed the factors that may contribute to fecal soiling after surgery for Hirschsprung's disease. Fifty-eight patients underwent surgery for Hirschsprung's disease and returned for follow up. The patients were divided into two groups based on the presence or absence of fecal soiling. The postoperative period, level of bowel pulled through, stool frequency, stool character, presence or absence of anorectal surgical complications, and manometric findings of the two groups were compared. Forty-three patients (40 boys, 3 girls, mean age 9.5 yr) had soiling and 15 (10 boys, 5 girls, mean age 10.2 yr) did not. Patients with soiling had significantly higher rates of anorectal surgical complications (60% vs 7%), abnormal stool character (75% vs 7%), stool frequency greater than three times per day (63% vs 20%), absence of rectoanal inhibitory reflex (33% vs 2%), and narrow anorectal pressure gradient (60% vs 13%) than those without. The results of manometric study suggested that a damaged internal sphincter or irritable neorectum might have contributed to fecal soiling. In conclusion, although anorectal surgical complications might result in both irritable neorectum and damaged internal sphincter, their effect on the neorectum (significantly increased rate of high resting rectal pressure) seemed to outweigh that on the internal sphincter. A competent anal sphincter and a less irritable neorectum after operation may therefore lower the likelihood of fecal soiling.

Anorectal function and endopelvic dissection in patients with repaired imperforate anus

Fifty-eight patients with anorectal malformations were closely followed up for postoperative anorectal function. Constipation was noted shortly after anorectoplasty in 10 of 28 low anomalies (35.7%) treated with limited sagittal anorectoplasty (LSARP), in 18 of 25 high or intermediate anomalies (72.0%) treated with posterior sagittal anorectoplasty (PSARP), but in none of 5 high or intermediate anomalies treated with Rehbein's mucosa-stripping endorectal pull-through and anterior sagittal perineal anorectoplasty (R-ASAP). The constipation resolved mostly within 1-2 years after repair under conservative management, but persisted beyond 2 years after repair in 3/25 children with LSARP and 10/25 with PSARP. Anal soiling was noted in 1/23 (4.3%) LSARP and 6/22 (27.3%) PSARP patients, but normal anorectal function was attained in 20/23 LSARP (86.9%) and 11/12 PSARP patients (50.0%) by the time of toilet training. Manometric studies disclosed that the resting rectal pressure (RRP) was lower and the anorectal pressure gradient (ARPG) higher in the constipated than the non-constipated children, while the RRP was higher and the ARPG lower in the soiled than the non-soiled patients. The ARPG after R-ASPA was close to that of non-constipated and in between that of the constipated and soiled patients. The rectoanal sphincter inhibitory reflex was not related to defecation status or surgical procedures, but showed a tendency toward positive conversion with time or after exclusion of esctatic terminal bowel in the severely constipated. It is concluded that anorectal function in patients with repaired imperforate anus seems to be more affected by the extent of endopelvic dissection than by preservation of the terminal bowel or sphincter muscles.

A giant retroperitoneal ganglioneuroma with intraspinal involvement: report of one case

A 9-year-old girl was discovered to have had a huge retroperitoneal mass causing moderate hydronephrosis and anterior displacement of the right kidney and which was found on a renal ultrasonographic examination. A series of examinations including (1)IVP, (2) abdominal computed tomography, (3) MRI and(4) incisional biopsy revealed a giant dumb-bell shaped retroperitoneal ganglioneuroma with intraspinal involvement. Secondary scoliosis was also noticed. We successfully resected the huge ganglioneuroma of the right retroperitoneum in a two stage procedure: her postoperative course was uneventful.

Ketoacidosis with hyperglycemia in heavy drinkers: a report of 12 cases

BACKGROUND

Heavy alcohol intake (> 45 g daily) might be a cause of diabetes. The short-term risks of heavy alcohol intake include ketoacidosis, glucose intolerance and pancreatitis. Alcoholic ketoacidosis (AKA) in combination with hyperglycemia mimics diabetic ketoacidosis (DKA). We described the characteristics of heavy drinkers with ketoacidosis and hyperglycemia but without a prior history of diabetes.

METHODS

Twelve habitually heavy drinkers who had not been previously diagnosed as diabetes were identified by reviewing the records of diabetic patients admitted to Chang Gung Memorial Hospital from 1989 to 1992. All of them met DKA criteria.

RESULTS

Elevated glycohemoglobulin (HbAlc) level is an indicator for the diagnosis of diabetes. Among these 12 patients, 10 had elevated levels of HbAlc and 2 had normal HbAlc levels. Of these 2 patients, 1 had an elevated level of HbAlc 6 months later; the other who was a female who after observation, had normal levels of HbAlc and glucose for the follow-up of two years.

CONCLUSION

We found that most heavy drinkers with both ketoacidosis and hyperglycemia also had diabetes as indicated by high levels of HbAlc. The only female patient had normal HbAlc and was diagnosed as AKA rather than DKA.

Splenic cysts in children

Splenic cysts were found, incidentally, in eight children during the past nine years (1987-1995) in Taipei Municipal Women's and Children's Hospital. Five of the children were boys and three were girls. The age at diagnosis ranged from 8 to 15 years. Evidence of possible splenic cyst development was found initially by ultrasonography; six patients received further evaluation with computerized tomography (CT); one patient received radionuclide scanning. The cysts ranged from 2 cm to 14 cm in diameter. Four of the patients received surgical treatment (three partial splenectomy and one total splenectomy) because of huge splenic cysts (diameter > 10 cm). Subsequent pathological examination revealed that all cysts had epithelial cell lining in the cyst wall, meaning they were all congenital in origin. The remaining four cases were followed up at the Out-patient Clinic here. All cases had a benign clinical course.

Mediastinal lymphangioma in an infant

Lymphangioma confined exclusively to the mediastinum occurs rarely in patients under 2 years of age. A 17-month-old girl presented with recurrent respiratory symptoms and signs. Chest radiographs taken at 9 and 17 months of age showed a large mediastinal mass, which had increased in size during the interval. Sonography revealed the mass to be cystic and multiloculated. Magnetic resonance imaging demonstrated a heterogeneous mass lying in the anterior and superior mediastinum and enveloping the great vessels. The child underwent a left thoracotomy and the tumor was almost completely removed. The pathologic diagnosis was cavernous lymphangioma. The postoperative course was uneventful. Lymphangioma, though rare, should be considered in the differential list of mediastinal tumors and cysts in infants.

T-tube drainage for the treatment of high jejunal atresia

Since 1976, the authors have used T-tube drainage for the treatment of diaphragmatic type, high jejunal atresia. Twelve cases were operated on. All cases survived the operation. On the fourteenth to thirtieth postoperative day, T-tubes were removed when the dilated proximal intestine returned to normal size.

Serial ultrasonic changes of the bladder diverticulum during urination: report of one case

A seven-year-old boy with a retrovesical diverticulum and ipsilateral renal dysplasia is reported. He had had a history of frequent urination and dysuria for four years. According to sonography, the volume of bladder diverticulum obviously changed during urination. The diverticulum presented as a temporary large reservoir of the bladder. In this case, serial ultrasonic changes assisted understanding of the role of the diverticulum during urination.

Renal hypoplasia, Gartner's duct cyst and imperforated hemivagina: report of a case

A girl with unilateral renal hypoplasia, ipsilateral Gartner's duct cyst and ipsilateral imperforate hemivagina is reported. She had a history of urinary drib-bling since early childhood. Recently, a foul bloody vaginal discharge was noted. Diagnosis was highly suspected on pelvic sonography, computerized tomography and magnetic resonance imaging, and was confirmed by punctures in the genitourinary tract with contrast study during surgery. This anomaly is extremely rare. Although three patients with similar conditions have been previously reported, different clinical presentations were noted in this patient.