[Stratified application of gene expression in diagnosis of thyroid nodules]

Objective: To investigate the value of BRAF V600E and multigene detection and stratified application for the diagnosis of thyroid nodules. Methods: A total of 1 117 patients with thyroid nodules resection at Nanjing Gulou Hospital from December 2020 to July 2022 were enrolled in the study. Fine needle aspiration (FNA) and core biopsy samplings were performed for cytopathologic examination and genetic testings; the findings were combined with BSRTC classification. The diagnostic performance of BRAF V600E and multigene detection were compared. Results: Among the 1, 117 patients who underwent thyroid nodules resection, 285 were male and 832 were female, with a median age of 46 years (range: 24-76 years). Postoperative histopathologic examination confirmed 1 040 cases of thyroid cancer and 77 cases of benign nodules. The sensitivity (87.0% vs. 80.8%, P<0.01) and diagnostic accuracy (87.9% vs. 82.1%, P<0.01) of multigene detection were significantly higher than those of BRAF V600E detection. The result of multigene detection showed that BRAF V600E mutation was the most common finding, followed by CCDC6-RET (E1-E12) fusion, ETV6-NTRK3 fusion, and KRAS mutation. Multigene detection had a higher sensitivity (81.9% vs. 72.8%, P<0.01) and lower cancer risk in wild-type (47.6% vs. 57.7%, P=0.069) than BRAF V600E detection in BSRTCⅠ-Ⅴ lesions. Compared with BRAF V600E detection, multigene had no significant difference of sensitivity in BSRTC Ⅰ lesions, but significantly higher sensitivity (86.3% vs 74.0%, P<0.01) in BSRTC Ⅲ lesions. Conclusions: Genetic detection can be used as an effective tool for the diagnosis of thyroid nodules. A stratified application of molecular markers in the diagnosis of thyroid nodules is proposed. Combined with FNA, single gene or multigene detection both can effectively assist in the diagnosis of thyroid nodules. Moreover, multigene detection is superior to single gene detection. For BSRTC Ⅲ lesion with wild-type BRAF, multigene detection can be considered with a repeated FNA.

Diagnosis based on electromagnetic navigational bronchoscopy-guided biopsied peripheral lung lesions in a 10-year-old girl: A case report

BACKGROUND

Electromagnetic navigational bronchoscopy (ENB) is an emerging diagnostic tool that enables practitioners to biopsy peripheral lung tissues that were previously only accessible under computed tomography (CT) guidance. However, few studies have investigated ENB use in children. Here, we report a case of a 10-year-old girl with peripheral lung lesions who complained of a 7-d persistent fever. She was diagnosed with Streptococcus parasanguinis infection based on findings obtained using ENB-guided transbronchial lung biopsy (TBLB).

CASE SUMMARY

A 10-year-old girl presented with constitutional symptoms of cough and fever of 7 days’ duration. Chest CT scans detected peripheral lung lesions and no endobronchial lesions. TBLB performed under the guidance of an ENB Lungpro navigation system was safe, well-tolerated, and effective for biopsying peripheral lung lesions. Examination of biopsied samples indicated the patient had a pulmonary Streptococcus parasanguinis infection, which was treated with antibiotics instead of more invasive treatment interventions. The patient’s symptoms resolved after she received a 3-wk course of oral linezolid. Comparisons of pre-treatment and post-treatment CT scans revealed absorption of some lung lesions within 7 mo of hospital discharge.

CONCLUSION

ENB-guided TBLB biopsying of peripheral lung lesions in this child is a safe, well-tolerated, and effective alternative to conventional interventions.

High-frequency monitoring of neonicotinoids dynamics in soil-water systems during hydrological processes

Neonicotinoids pollution poses a serious threat to aquatic ecosystems. However, there is currently little knowledge about how neonicotinoids are transferred from the agricultural environment to the aquatic environment. Here, we conducted in situ high-frequency monitoring of neonicotinoids in soil-water systems along the hydrological flow path during rainfall to explore the horizontal and vertical transport mechanisms of neonicotinoids. The collected samples included 240 surface runoff, 128 subsurface runoff, 60 eroded sediment, 120 soil and 144 soil solution, which were used to analyse neonicotinoids concentrations. Surface runoff, subsurface runoff and eroded sediment were the three main paths for the horizontal migration of neonicotinoids. In the CK (citrus orchards without grass cover) and grass-covered citrus orchards, there are 15.89% and 2.29% of the applied neonicotinoids were transported with surface runoff, respectively. While in the CK and grass-covered citrus orchards, there are only 1.23% and 0.19% of the applied neonicotinoids were transported with eroded sediment and subsurface runoff. Although the amount of neonicotinoids lost along with eroded sediment was small, the concentration of neonicotinoids in eroded sediment was two orders of magnitude higher than the concentration of neonicotinoids in sediments of the surface water. Meanwhile, neonicotinoids migrated vertically in soil due to water infiltration. In the CK and grass-covered citrus orchards, there are 57.64% and 24.36% of the applied neonicotinoids were retained in soil and soil solution, respectively, and their concentration decreased as soil depth increased. Another noteworthy phenomenon is that more neonicotinoids migrated to deeper soil layers under grass cover compared with no grass cover because grass roots promoted the formation of cracks and vertical preferential flow. Our results are expected to improve the accuracy of neonicotinoids pollution prediction by considering migration paths, including surface and subsurface runoff and eroded sediment.

[Mid-term efficacy of sacral nerve stimulation for the treatment of chronic constipation]

Objective: To investigate the mid-term efficacy of sacral nerve stimulation (SNS) for chronic constipation. Methods: A descriptive case series study was conducted. Patients with chronic constipation were treated in Xijing Hospital of Digestive Disease from February 2013 to December 2018 were retrospectively enrolled. The types of constipation were confirmed based on colon slow transit test, anorectal manometry and defecography in Xi'an Mayinglong Coloproctological Hospital. This study has been registered in China clinical trial registry (Registration No.: ChiCTR-ROC-16008945). Case inclusion criteria: (1) constipation was diagnosed according to Rome III criteria; (2) traditional treatment, including education, diet adjustment, laxative, biofeedback treatment, failed for at least 1 year; (3) there were no constipation-related organic diseases. After excluding neurogenic diseases, including spinal cord injury and multiple sclerosis, 21 patients were included in this study. There were 10 males and 11 females, with an average age of 50.9 (14-76) years. After the relevant examination and evaluation of patients, they underwent percutaneous nerve evaluation (PNE). If patient experienced a good response to PNE after 2 or 3 weeks (≥50%), permanent SNS implantation was performed. The improvement of clinical symptoms and quality of life between the baseline, PNE, and latest follow-up time points were compared. Improvement of clinical symptoms, including autonomic stool frequency per week, autonomic stool days per week, defecation time, visual analogue scale (VAS, lower score indicates more serious symptoms) score and Cleveland clinic constipation score (CCCS, higher score indacates more serious symptoms) criteria. The change of quality of life was scored by SF-36 questionnaires (the higher score indicates better quality of life). Results: Of 21 patients, 18 (85.7%) experienced significant improvement in symptoms with PNE, and 2 patients discontinued treatment due to their dissatisfaction. Sixteen patients (76.2%) received permanent SNS implantation, two of whom underwent bilateral PNE implantation. These patients were followed-up for mean 56 (34-72) months. The treatment was continuously effective in 13 patients (61.9%), including 3 of ODS, 1 of STC and 9 of mixed constipation. Compared with baseline, the score of constipation patients receiving permanent SNS implantation at latest follow-up was shown. The median autonomic stool frequency per week increased from 1.0 (0-7) to 7.5 (0-10) (P<0.001), the median autonomic stool days per week increased from 1.0 (0-7) d to 4.5 (0-7) d (P<0.001), the median defecation time decreased from 19.0 (8-40) minutes to 4.0 (3-31) minutes (P<0.001), the median CCCS decreased from 20.0 (13-30) to 9.0 (6-30) (P<0.001), and the median VAS score increased from 9.0 (7-40) to 80.0 (15-90) (P<0.001). The values of the 8 parts of the SF-36 questionnaire increased (all P<0.05). Conclusion: SNS implantation is safe and has obvious effects on severe constipation with stable mid-term efficacy.

Ultrasound volume projection image quality selection by ranking from convolutional RankNet

Periodic inspection and assessment are important for scoliosis patients. 3D ultrasound imaging has become an important means of scoliosis assessment as it is a real-time, cost-effective and radiation-free imaging technique. With the generation of a 3D ultrasound volume projection spine image using our Scolioscan system, a series of 2D coronal ultrasound images are produced at different depths with different qualities. Selecting a high quality image from these 2D images is the crucial task for further scoliosis measurement. However, adjacent images are similar and difficult to distinguish. To learn the nuances between these images, we propose selecting the best image automatically, based on their quality rankings. Here, the ranking algorithm we use is a pairwise learning-to-ranking network, RankNet. Then, to extract more efficient features of input images and to improve the discriminative ability of the model, we adopt the convolutional neural network as the backbone due to its high power of image exploration. Finally, by inputting the images in pairs into the proposed convolutional RankNet, we can select the best images from each case based on the output ranking orders. The experimental result shows that convolutional RankNet achieves better than 95.5% top-3 accuracy, and we prove that this performance is beyond the experience of a human expert.

[Commuting mode specific exposure to PM(2.5) in urban area of Guangzhou]

Objective: To find the differences in PM(2.5) exposure level in the context of four commuting modes (by walk, bicycle, bus and subway) in Guangzhou. Methods: The PM(2.5) exposure assessment was carried out from January to December 2015 in Guangzhou. PM(2.5) was measured by using SidePak individual dust meter (AM510, TSI Inc. USA) with time interval of 1 minute. Our measurement was taken on Monday, Wednesday, Friday and Sunday in the second week of each month and the samples were collected in the morning (07:00-09:00), afternoon (11:00-13:00) and evening (17:00-19:00). Results: A total of 284 air samples during walking, 281 air samples during bicycle riding, 278 air samples in bus, and 280 air samples in subway were collected. The median PM(2.5) concentrations exposed during walking, during bicycle riding, in bus and in subway were 38.4, 38.6, 23.3 and 24.1 μg/m(3), respectively, which were positive correlated with exposure concentration in fixed surveillance sites. The exposure level was lowest in summer, and highest in winter. The median of one-way exposure level to PM(2.5) from high to low were as follows: 21.0 μg for bicycle riding, 20.1 μg for walking, 5.1 μg for taking bus and 2.6 μg for taking subway. The season and time specific one-way exposure levels to PM(2.5) of four commuting modes were consistent. Conclusions: The exposure level to PM(2.5) was obviously higher during walking and bicycle riding than that in bus and subway. The exposure level to PM(2.5) during walking was higher than that during bicycle riding, in bus and in subway.

[Schofield and the first spread of western medicine in Shanxi]

After the Second Opium War, the signing of the Tientsin Treaty and the Peking Treaty legitimized the missionary activities and authorized the missionary the rights to enter inland China for propagating their religious doctrines. In the late 1870s, the"The extraordinary famine of the Ding Wu year"and the subsequent epidemic provided the opportunity for missionaries to enter Shanxi. Dr. Schofield, sent by the China Inland Mission, arrived in Taiyuan in 1880, set up clinics and practised there. He died of typhus after treating a typhus patient in the summer of 1883. Schofield stayed and practised in Taiyuan for 2 years and 8 months. Later, the China Inland Mission and other missionaries donated to establish a Shanxi's first western medicine Hospital to commemorate Schofield. The medical activities of Dr. Schofield enlightened and promoted the Shanxi people's understanding of western medicine.

Mapping QTLs for drought tolerance in an F2:3 population from an inter-specific cross between Gossypium tomentosum and Gossypium hirsutum

Cotton is one of the most important natural fiber crops in the world. Its growth and yield is greatly limited by drought. A quantitative trait locus (QTL) analysis was therefore conducted to investigate the genetic basis of drought tolerance in cotton (Gossypium spp) using 188 F2:3 lines developed from an inter-specific cross between a wild cotton species, G. tomentosum, and an upland cotton, G. hirsutum (CRI-12). A genetic map was constructed using 1295 simple sequence repeat markers, which amplified 1342 loci, distributed on 26 chromosomes, covering 3328.24 cM. A field experiment was conducted in two consecutive years (2014 and 2015) and 11 morphological and physiological traits were recorded under water-limited (W1)/well-watered (W2) regimes at three growth stages (bud, flowering, and full boll). The traits measured included chlorophyll content, plant height, leaf area, leaf number, leaf fresh weight, leaf dry weight, boll weight, number of bolls per plant, and the number of fruiting branches. Sixty-seven and 35 QTLs were found under the W1 and W2 conditions, respectively. Of these, the majority exhibited partial dominance or over-dominance genetic effects for increasing the trait values. Four consistent QTLs were found under the W1 treatment on chromosomes 5, 8, 9, and 16, whereas no consistent QTL was found in W2. Thirteen QTL clusters were also identified on nine chromosomes (2, 3, 5, 6, 9, 14, 15, 16, and 21). These results will help to elucidate the genetic basis of drought tolerance in cotton.

[Transapical transcatheter aortic valve replacement for high risk elderly patients with predominant aortic incompetence]

OBJECTIVES

To introduce the application of the J-Valve™ system in elderly patients with predominant aortic incompetence without significant valve calcification, and to evaluate its feasibility.

METHODS

From April 2014 to July 2015, 33 cases of transapical implantation of J-Valve™ were performed in Department of Cardiac Surgery, Zhongshan Hospital, Fudan University. Sixteen of these patients were diagnosed as predominant aortic incompetence without significant valve calcification. There were 11 male and 5 female patients aged from 61 to 84 years, with a mean age of (76±6) years. All patients had symptoms of left ventricular dysfunction for at least 3 months. They were considered to be prohibitive for surgical valve replacement (logistic European system for cardiac operative risk evaluation: 22.2% to 44.4%, mean 27%±6% after evaluation by an interdisciplinary heart team. The J-Valve™ system was applied in transapical transcatheter aortic valve replacement for patients. The multi-slice CT was performed before discharge. Clinical evaluation including patients' history, symptoms and New York Heart Association classification and echocardiogram evaluation were performed before discharge, 1(st) month, 3(th) month and 12(th) month after the operation respectively.

RESULTS

Implantations were successful in all patients. One patient died from moderate paravalvular leak which led to multi-organ failure during the hospital stay. The mean time of postoperative hospital stay of the other 15 patients was (6.1±1.3) days. The 15 patients were followed by 174 to 410 days, with a median time of 188 days. Only two patients had trivial prosthetic valve incompetence, the other 13 patients had no prosthetic valve incompetence; two patients had no paravavular leak and the other 13 patients had paravavular leak of no more than moderate grade. There were no major complication or mortality during the follow-up.

CONCLUSIONS

The transapical implantation of the J-Valve™ system in high risk elderly patients with predominant aortic incompetence is feasible.The early postoperative outcome is satisfactory.

Successful ABO-incompatible living-related intestinal transplantation: a 2-year follow-up

ABO-incompatible intestinal transplantation has rarely been performed due to poor patient outcomes. Herein we present a case of successful ABO-incompatible intestinal transplantation with a 2-year follow-up. A 16-year-old female with a history of extensive bowel resection received an ABO-incompatible living donor bowel graft from her father (blood type AB graft into a type A recipient). Posttransplant immunosuppression consisted of an initial anti-CD20, plasmapheresis/intravenous immunoglobulin before transplantation, followed by an anti-thymocyte globulin (ATG) induction and splenectomy, and maintenance with tacrolimus and prednisone. Her postoperative course was remarkable for a single episode of rejection on day 14 which responded promptly to treatment with methyprednisolone and ATG. Three months after transplantation, the patient developed an abdominal abscess requiring open surgical drainage. No viral infections were encountered. Posttransplant anti-B antibody titers and anti-B7 donor-specific antibody levels remained low. At a 2-year follow-up, the patient showed a progressive weight gain of 5.0 kg. This case illustrates that ABO-incompatible living-related bowel transplantation is immunologically feasible and is associated with good outcomes for the recipient. The management of blood type antibodies and the use of adequate immunosuppression in the early period of the procedure may be the keys to the success of future cases.

Establishing a conceptual model for photochemical ozone pollution in subtropical Hong Kong

Photochemical ozone (O₃) formation is related to its precursors and meteorological conditions. A conceptual model of O₃ air pollution is developed based on the analysis of data obtained at Tung Chung (TC) in Hong Kong. By comparing meteorological parameters between O₃ and non-O₃ episode days, it was found that high temperatures, strong solar radiation, low wind speeds and relative humidity, northeasterly and/or northwesterly prevailing winds were favorable for the O₃ formation, while tropical cyclones were most conducive to the occurrence of O₃ episodes. Backward trajectories simulation and graphical illustration of O₃ pollution suggested that super-regional (i.e. central and eastern China) and regional (i.e. Pearl River Delta, southern China) transport was another factor that contributed to high O₃ levels in Hong Kong. The photochemical O₃ formation, generally VOC-limited in Hong Kong, was controlled by a small number of volatile organic compounds (VOCs). Furthermore, the positive matrix factorization (PMF) simulation suggested that solvent usage and vehicular emissions are the major contributors to ambient VOCs in Hong Kong. Finally, this paper presents recommendations for further O₃ research and implementation of O₃ control strategies.

Polymorphic microsatellite loci for the genetic analysis of Lycoris radiata (Amaryllidaceae) and cross-amplification in other congeneric species

Lycoris radiata is a perennial herb that has been used in traditional Chinese medicine for a long time and has two main medicinal components in its bulb, lycorine and galanthamine. However, the original microsatellite loci have not been developed for any species of Lycoris. Total genomic DNA was extracted from fresh bulbs using a modified CTAB protocol. We isolated 10 microsatellite loci from 21 L. radiata individuals of a natural population from Yellow Mountain in Anhui Province, China. The number of alleles ranged from two to nine. The observed and expected heterozygosities ranged from 0.238 to 0.952 and from 0.455 to 0.784, respectively. One locus significantly deviated from Hardy-Weinberg equilibrium and no significant linkage disequilibrium was found between pairs of loci. Cross-species amplification of these microsatellite loci was characterized in additional five species (L. sprengeri, L. anhuiensis, L. albiflora, L. longituba, and L. chinensis) of Lycoris. The results suggest that these microsatellite markers would contribute to the population genetic studies of L. radiata and other related species.

Pulmonary peptide delivery: effect of taste-masking excipients on leuprolide suspension metered-dose inhalers

The purpose of this study was to evaluate the effect of taste-masking excipients on in vitro and in vivo performance of a leuprolide metered-dose inhaler (MDI) suspension formulation. Taste-masking excipients (aspartame and menthol) were added to a leuprolide suspension MDI formulation. The leuprolide MDI formulation with the taste-masking excipients was characterized in terms of milling time, particle size distribution, dose delivery and uniformity, and drug absorption in dogs. The data were compared with a formula that did not contain taste-masking excipients. It was found that the longer milling time for the leuprolide suspension with the taste-masking excipients was required to obtain a similar particle size distribution compared with the formula without taste-masking excipients using a fluid energy mill. Although measurable differences in mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) were not observed between the two formulations, the percent of particles < or = 5 microns and the actuator retention for the formula with the taste-masking excipients were significantly different from the formula without taste-masking excipients using the Marple-Miller cascade impactor. Taste-masking excipients did not show a significant effect on valve delivery and through-can dose uniformity. However, the mean ex-actuator dose was 150.4 mg for the formula with the taste-masking excipients and 162.2 mg for the reference formula, respectively, indicating a significant difference. In tracheostomized dogs, both formulations showed comparable pharmacokinetic parameters including Cmax, Tmax, AUC0-12 and bioavailability (F%), indicating that the taste-masking excipients do not have an effect on lung absorption of leuprolide acetate. Therefore, inclusion of taste-masking excipients in the leuprolide MDI suspension formulation showed a significant impact on drug micronization, exactuator dose, and particle deposition pattern. Mechanistically, the unfavorable performance of leuprolide MDI in the presence of taste-masking excipients could be due to modification of the properties of the suspension itself and alteration of propellant evaporation following actuation.

[Cloning of cancer-related genes of Rat6 fibroblasts by using an improved differential display method]

The p53 gene is the most frequently mutated gene identified so far in human cancers. When a mutant p53(135)-val gene was allowed to be over-expressed in Rat6(R6) cells, a high incidence of spontaneous transformation was observed in long-term culture of this cell line(R6 # 13-8). To identify genes involved in cell transformation, parental p53 over-expressing cell, R6 # 13-8, and its spontaneous transformant T2, were analyzed by an improved mRNA differential display technique, which was reproducible, simpler, and was able to clone cDNA longer than 500 bp, and was with less false positives. When 33 10-mer or 12-mer single primers with arbitrary but defined sequence were used for PCR, over 90 discrete cDNAs were obtained from R6 # 13-8 and T2 cells. Three differentially expressed cDNAs were identified, one of them is highly expressed in T2 cells, while the other two, 0.8 kb and 0.9 kb long, are highly expressed in R6 # 13-8 cells. The latter were cloned and confirmed by Northern hybridization. Both cloned fragment were not homologous with any published sequence. Our results suggest that the activation and inactivation of genes are involved in the process of the spontaneous transformation from R6 # 13-8 to T2.

Differentiating normal from abnormal inferior thoracic paravertebral soft tissues on chest radiography in children

OBJECTIVE

The purposes of this investigation were to define the normal appearances, define factors that have the potential to influence appearance, and establish defined criteria to differentiate normal from abnormal appearances of posteroinferior paravertebral soft tissues on chest radiography in children.

SUBJECTS AND METHODS

Paravertebral soft tissues were evaluated on frontal chest radiographs in 23 children with documented abnormalities and 275 children without abnormalities in the region. The frequency of visualization, course, width, and factors (patient positioning, age, and sex) potentially influencing the appearance of paravertebral soft tissues were determined. Inferolateral course and width greater than that of the adjacent pedicle were evaluated as criteria for abnormality.

RESULTS

Only 28% of the children without abnormalities had paravertebral soft tissues visualized, and the frequency of visualization directly increased with age (p = 0.001). For identification of abnormal cases on the left side, width greater than the adjacent pedicle had a sensitivity of 100% and a specificity of 98%, and inferolateral course had a sensitivity of 86% and a specificity of 95%. Visualization on the right side (n = 5) was always abnormal. Six normal cases had a width greater than that of the adjacent pedicle on the left side on initial radiographs obtained with supine positioning and met normal criteria on repeated radiographs with upright positioning.

CONCLUSION

Width greater than the adjacent pedicle is the best radiographic criterion for differentiation of abnormal from normal left-sided paravertebral soft tissues, particularly on radiographs obtained with upright positioning. Identifiable right-sided paravertebral soft tissue is always abnormal. These criteria are useful aids in determining the need for additional imaging, such as CT.

Identification and characterization of genes whose expressions are altered in rat 6 fibroblasts transformed by mutant p53(val135)

The wild-type tumor suppressor gene p53 is known as a transcription factor in activating or suppressing target genes that encode proteins in regulating genome stability, DNA damage, cell arrest, and apoptosis. However, the role of mutant p53 in the process of cell transformation is still unclear. Our recent work indicated that overexpression of mutant p53(val135) induced high incidence of spontaneous transformation in prolonged cultures of Rat 6 fibroblasts. In order to identify genes related to neoplastic transformation induced by the mutant p53, the p53(val135)-overexpressor R6#13-8 and its derived spontaneously transformed cell line T2 were analyzed by mRNA differential display. In a systematic screening with 80 primer sets of RT-PCR reactions, three genes were found to be differentially expressed between R6#13-8 and T2 cells. Two genes, identified as homologues of the growth factor inducible immediate-early gene Cyr61 and the human nonmuscle myosin heavy chain-B, were down-regulated in T2 cells. Interestingly, both genes were also suppressed in Rat 6 cells transformed by c-H-ras and v-myc, but not by v-src genes. The third gene is a homologue of the frizzled related protein, a gene family that acts, in some cases, as an antagonist to the Wnt signaling pathway. It is intriguing that the rat homologue of the frizzled related protein was only expressed in p53(val135)-overexpressing cells, but not in the parental Rat 6 cells. However, the same gene was also highly expressed in ras-transformed Rat 6 cells, and moderately expressed in v-src-transformed Rat 6 cells. This is the first study in which the association of mutant p53 to these three genes is revealed. Our current report may provide new clues to the role of mutant p53 in the process of cell transformation.

Optimizing contrast-enhanced abdominal CT in infants and children using bolus tracking

OBJECTIVE

Manual administration of IV contrast material results in unpredictable injection rates. Our purpose was to determine the effect of bolus tracking on overall abdominal helical CT scan quality, particularly on hepatic enhancement, in children with manually administered contrast media.

MATERIALS AND METHODS

We compared 33 abdominal helical CT scans of 29 children in whom bolus tracking was used with 22 CT scans of a control group of 21 children in whom bolus tracking was not used. All contrast material was administered by manual injection. Qualitative assessment was made of organ and vessel enhancement and overall scan appearance. Quantitative assessment using region-of-interest cursors was performed at three anatomic levels, and the results for the two groups of children were compared.

RESULTS

Qualitative comparison of enhancement parameters between the bolus tracking group (number given first) and the control group (number given second) yielded the following: splenic artifact in 9% versus 23% (p = .24); inferior vena cava flow artifact in 3% versus 27% (p = .01); scanning during the nephrographic phase in 89% versus 59% (p = .02); and good quality grade in 79% versus 64% (p = .23). Significantly greater hepatic enhancement (as measured in mean Hounsfield units) was achieved in the bolus tracking group than in the control group at the superior (48.5 versus 28.6; p < .001), middle (47.9 versus 32.3; p < .001), and inferior (48.2 versus 36.5; p = .01) levels. Hepatic enhancement increased significantly from the superior to the inferior level in the control group (p < .02), whereas enhancement was homogeneous in the bolus tracking group (p > .50).

CONCLUSION

Bolus tracking provides improved contrast enhancement, including significantly greater hepatic enhancement, during abdominal helical CT in children in whom the rate of injection of contrast material is unpredictable.

[Molecular cloning of two Rab family proteins, S2 and S10]

Rab family proteins play important roles in vesicular transport. In mammals, more than 30 members of this family have been reported to date. I report here the cDNA cloning and analysis of the genomic organization of two Rab family proteins, S2 and S10. Mouse S2 cDNA was isolated from a spleen cDNA library. S2 encoded a novel Rab family protein with highest homology to human S10. Mouse S10 cDNA was isolated from a brain cDNA library. Mouse S10 was 92% homologous at the nucleotide level and 98% identical at the amino acid level to human S10. The amino acid sequences of mouse S2 and S10 were 55% identical, and these two proteins shared unique amino acid sequences at the effector domain. Mouse S2 and S10 genes were isolated from a genomic library. The genomic organization of these two genes was essentially identical, having two exons and a single intron. This structure was unique among reported rab family genes. These findings suggest that S2 and S10 would make a subgroup in Rab family. The phylogenetic tree made by a computer program was consistent to this idea. Northern blotting of mouse tissue RNAs indicated that S2 gene was expressed ubiquitously, whereas S10 gene was almost exclusively expressed in the brain. These results suggest that S2 and S10 play similar roles in vesicular transport, whereas S10 has more specialized function in the nervous system.

A novel Rab GTPase, Rab33B, is ubiquitously expressed and localized to the medial Golgi cisternae

Small GTP-binding proteins of the Rab family play important roles at defined steps of vesicular transport in protein secretion and the endocytosis pathway. In mammals, more than 30 proteins belonging to the Rab family have been reported to date. We report here the molecular cloning and characterization of a novel Rab protein, Rab33B. The amino acid sequence of Rab33B shows 55.3% identity to the Rab33A protein (previously called S10), and these two proteins share unique amino acid sequences at the effector domain. The genomic organization of rab33B was the same as rab33A: it consists of two exons. Thus, these two proteins make a subclass within the Rab family. Northern blot analysis showed that rab33B is expressed ubiquitously in mouse tissues, in contrast to rab33A whose expression is restricted to the brain and the immune system. A 26 kDa protein was detected by western blotting using a Rab33B-specific monoclonal antibody. Using immunofluorescence studies, Rab33B was shown to co-localize with (alpha)-mannosidase II, a Golgi-specific marker. Immunoelectron microscopy analysis further defined the localization of Rab33B to the medial Golgi cisternae. These results suggest Rab33B plays a role in intra-Golgi transport.

Structure and expression of the mouse S10 gene

We previously reported the cloning of a human S10 cDNA which encodes a small GTP-binding protein belonging to the Rab subfamily. Here we describe a mouse S10 cDNA and its genomic structure. Mouse S10 is 92.3% homologous at the nucleotide level and 98.3% identical at the amino acid level compared to human S10. The mouse S10 gene is comprised of two exons and a single intron. Northern blotting of tissue RNAs indicates that the S10 gene is predominantly expressed in brain.

Review of pneumatic reduction of intussusception: evolution not revolution

Pneumatic insufflation of the colon for reduction of pediatric intussusception has recently been recognized in the United States as an alternative method for the more traditional hydrostatic reduction with contrast material. The experience with pneumatic reduction in China is extensive; more than 14,000 cases have been reported in the English language literature. In this review, the general technique used in China is summarized, and the international experience with air insufflation is included in a comparison of hydrostatic and pneumatic reduction techniques.

Fluorescent banding pattern analysis of eight taxa of Phaseolus and Vigna in relation to their phylogenetic relationships

Phylogenetic relationships among eight taxa of seven species of Phaseolus and Vigna (Phaseolus angularis, P. aureus, P. calcaratus, P. coccineus, P. vulgaris, Vigna sesquipedalis and V. sinensis; 2n = 22 each) were studied by the fluorescent chromosome banding technique. Preparations of somatic metaphase chromosomes of each taxon were sequentially stained with Giemsa, GC-specific fluorochrome chromomycin A3 (CMA) and AT-specific fluorochrome 4'-6-diamidino-2-phenylindole (DAPI). On the basis of the fluorescent banding patterns of the 22 chromosomes of each taxon, P. angularis, P. coccineus (from China and Korea) and P. vulgaris were grouped into one group ("Phaseolus group"), P. aureus and two Vigna species were grouped into another ("Vigna group") and P. calcaratus was grouped in an independent group.

Status of clinical MR evaluations 1985-1988: baseline and design for further assessments

The authors modified the methods used by Cooper et al (JAMA 1988; 259:3277-3280) to describe magnetic resonance (MR) clinical research during 1985-1988 in an objective manner. To avoid other shortcomings faced by Cooper et al, the authors randomly sampled 500 articles and obtained estimates of probable errors. Excluding case reports, all 40 of the studies with human subjects provided some evidence of prior research planning, which compares favorably with the 22% found by Cooper et al. Use of a standard for truth was similar between the data sets. Observer blinding, random ordering of procedures, and assessment of interobserver variability continued to be uncommon. Most studies provided only minimal statistical information. The work of these authors provides a study design and the baseline needed for future assessments of MR imaging evaluations.

[Functional change of colorectal adenoma and its relation with colorectal adenocarcinoma--application of mucin histochemical and immunohistochemical techniques]

Using HE, AB/PAS, HID/AB, PAT/KOH/PAS stain and CEA monoclonal antibody BA stain techniques, composition of mucin and distribution of CEA in the tumor tissue were detected in 65 cases of colorectal tubular adenoma, 7 adenoma with malignant change and 14 established tubular adenocarcinoma in order to study the functional changes of colorectal adenoma and its relation with the colorectal adenocarcinoma. According to Konishi's criteria, colorectal tubular adenomas were divided into three groups: mild, moderate and severe dysplasia, added with two of ours: adenoma with malignant change and established adenocarcinoma, totalling 5 groups for comparison. The results showed that CEA positive rate increased with the grade of dysplasia in these 5 groups (33%, 57%, 67%, 86% and 100%). Similarly, the percentage of non-acetylated acid and C7 C9 O-acetylated sialomucin also gradually increased with the grade of dysplasia, showing a parallel tendency. Epithelial cells, secreting a heterogeneous mucin, could be taken as a signal of abnormal cellular differentiation. The increase of non-acetylated acid and C7 C9 O-acetylated sialomucin in colorectal adenoma implies a likelihood of malignant change.