[Efficacy of different regimens and prognostic factors in patients with first relapsed multiple myeloma treated after front-line bortezomib, cyclophosphamide, and dexamethasone]

Objective: To analyze the efficacy of second-line regimens and prognostic factors in patients with first-relapsed multiple myeloma (MM) treated with bortezomib, cyclophosphamide, and dexamethasone (BCD). Methods: A retrospective cohort study. Clinical data were collected in first-relapsed MM patients after BCD treatment from three tertiary hospitals in north China from July 2009 to October 2022. Patients were classified according to the second-line regimen into the immunotherapy group, single novel agent group [either proteasome inhibitor (PI) or immunomodulatory drug (IMiD)], combination treatment group (both PI+IMiD), and traditional treatment group. Responses to second-line regimens and survival data were analyzed. The Kaplan-Meier method was used for survival analysis and the Cox proportional risk model was used for univariate and multivariate analyses. Results: A total of 217 patients were enrolled including 8.8% (19/217) in the immunotherapy group, 48.4% (105/217) in the PI/IMiD group, 29.9% (65/217) in the PI+IMiD group, and 12.9% (28/217) in the traditional treatment group. The median age was 62 years (range 31-83 years) and 56.2% (122/217) were males. The overall response rates (ORRs) in the four groups were 94.7% (18/19) vs. 56.2% (59/105) vs. 73.8% (48/65) vs. 32.1% (9/28) (χ2=24.55; P<0.001), respectively. The progression-free survival (PFS) of the second-line regimens (2ndPFS) was 17.7 vs. 9.0 vs. 9.2 vs. 4.6 months (χ2=22.74; P<0.001), respectively, among which patients in the PI/IMiD and PI+IMiD groups had comparable 2ndPFS (χ2=1.76; P=0.923). Patients with high-risk cytogenetic abnormalities (HRCAs) achieved the longest 2ndPFS of 22.0 months in the immunotherapy group (χ2=15.03; P=0.002). Multivariate analysis suggested that immunotherapy (HR=0.11, 95%CI 0.05-0.27), achievement of efficacy of partial response or better (HR=0.47, 95%CI 0.34-0.66), and non-aggressive relapse (HR=0.25, 95%CI 0.17-0.37) were independent prognostic factors of 2ndPFS. Conclusion: In this real-world study, immunotherapy was associated with a more favorable efficacy and PFS for first-relapsed MM patients after BCD treatment, with similar outcomes in patients with HRCAs.

[Analysis of the efficacy and influencing factors of sodium channel blockers in the treatment of focal epilepsy in infants under 6 months of age]

Objective: To analyze the efficacy and safety of the sodium channel blockers (SCB) antiseizure medication in the treatment of focal epilepsy in infants under 6 months of age. Methods: This was a case series study. Infants with focal epilepsy with onset within 6 months of age and treated with SCB attending the Department of Neurology of Beijing Children's Hospital from June 2016 to April 2022 were collected. The clinical data, auxiliary examinations, SCB application, efficacy, adverse reactions, and prognosis were analyzed retrospectively. Patients were grouped according to type of seizure and epileptic syndrome, age of onset and etiology. Chi square test and Fisher exact test were used to analyze the differences between groups statistically. Results: A total of 118 infants were enrolled, 65 males and 53 females, with an age of epilepsy onset of 56 (4, 114) days. Developmental and epileptic encephalopathy was diagnosed in 60 infants, 39 had self-limited neonatal and (or) infantile epilepsy, and 19 had non-syndromic focal epilepsy. Application of SCB: 106 used oxcarbazepine, 2 used lacosamide, 9 switched from oxcarbazepine to lacosamide or a combination of 2 SCB, and 1 used oxcarbazepine, lacosamide, and lamotrigine successively; oxcarbazepine was the first choice in 46 cases. The age at which SCB was applied was 103 (53, 144) days. The children were followed up for 6 months to 6 years. SCB was effective in 89 cases (75.4%), including 70 cases (59.3%) who achieved seizure freedom. The seizure-free rate was higher in the focal epilepsy only group than in the group with other seizure types (64.4% (65/101) vs. 4/17, χ²=9.99, P<0.05). The responder and seizure-free rates were all higher in the group with the onset age of >3-6 months than the group >1-3 months (84.4% (38/45) vs. 62.5% (20/32), 73.3% (33/45) vs. 46.9% (15/32), χ²=4.85 and 5.58, both P<0.05). With the exception of variants in the PRRT2 gene, those with variants in sodium or potassium channels had higher responder and seizure-free rates than those with variants in other genes(86.2% (25/29) vs. 45.5% (10/22), 62.1% (18/29) vs. 22.7% (5/22), χ²=9.65 and 7.82,both P<0.05). The most common adverse event was transient hyponatremia, which happened in 66 cases (55.9%). There were 9 cases of rash, which subsided in 6 cases after discontinuing oxcarbazepine and switching to lacosamide, and 7 cases of electrocardiogram abnormalities, which improved after withdrawing oxcarbazepine and changing to lacosamide in 1 case. Conclusion: SCB are effective and tolerable in the treatment of focal epilepsy in infants under 6 months of age, with better efficacy in patients with genetic variants of the sodium or potassium channel, focal seizures only, and seizure onset >3-6 months of age.

Estimating potassium in potato plants based on multispectral images acquired from unmanned aerial vehicles

Plant potassium content (PKC) is a crucial indicator of crop potassium nutrient status and is vital in making informed fertilization decisions in the field. This study aims to enhance the accuracy of PKC estimation during key potato growth stages by using vegetation indices (VIs) and spatial structure features derived from UAV-based multispectral sensors. Specifically, the fraction of vegetation coverage (FVC), gray-level co-occurrence matrix texture, and multispectral VIs were extracted from multispectral images acquired at the potato tuber formation, tuber growth, and starch accumulation stages. Linear regression and stepwise multiple linear regression analyses were conducted to investigate how VIs, both individually and in combination with spatial structure features, affect potato PKC estimation. The findings lead to the following conclusions: (1) Estimating potato PKC using multispectral VIs is feasible but necessitates further enhancements in accuracy. (2) Augmenting VIs with either the FVC or texture features makes potato PKC estimation more accurate than when using single VIs. (3) Finally, integrating VIs with both the FVC and texture features improves the accuracy of potato PKC estimation, resulting in notable R 2 values of 0.63, 0.84, and 0.80 for the three fertility periods, respectively, with corresponding root mean square errors of 0.44%, 0.29%, and 0.25%. Overall, these results highlight the potential of integrating canopy spectral information and spatial-structure information obtained from multispectral sensors mounted on unmanned aerial vehicles for monitoring crop growth and assessing potassium nutrient status. These findings thus have significant implications for agricultural management.

Features of gastric cancer by anatomic subsite in northern China: A multi-center Health Science Report database study

BACKGROUND

The features of gastric cancer based on the anatomic site remain unknown in northern China patients.

AIM

To analyze gastric cancer features and associated trends based on the anatomical site in northern China patients.

METHODS

This cross-sectional study used incident gastric cancer case data from 10 Peking University-affiliated hospitals (2014 to 2018). The clinical and prevailing local features were analyzed.

RESULTS

A total of 10709 patients were enrolled, including antral (42.97%), cardia (34.30%), and stomach body (18.41%) gastric cancer cases. Cancer in the cardia had the highest male:female ratio, proportion of elderly patients, and patients with complications, including hypertension, diabetes, cerebrovascular, and coronary diseases (P < 0.001). gastric cancer involving the antrum showed the lowest proportion of patients from rural areas and accounted for the highest hospitalization rate and cost (each P < 0.001). The proportion of patients with cancer involving the cardia increased with an increase in the number of gastroesophageal reflux disease cases during the same period (P < 0.001). Multivariate analysis revealed that tumor location in the cardia increased the risk of in-hospital mortality (P = 0.046). Anatomical subsite was not linked to postoperative complications.

CONCLUSION

The features of gastric cancer based on the anatomical site differ between northern China and other regions, both globally and within the country. Social factors may account for these differences and should affect policy-making and clinical practice.

[Pathogen distribution and antimicrobial resistance among lower respiratory tract infections in patients with hematological malignancies]

Objective: To investigate the pathogen distribution and antimicrobial resistance among lower respiratory tract infections in patients with hematological malignancies. Methods: Sputum samples were collected from 967 patients with hematological malignancies and lower respiratory tract infections in Department of Hematology,the Second Hospital of Shanxi Medical University from January 2017 to July 2020. The pathogens and drug sensitivity reports were carried out by automatic bacterial identification instruments. WHONET 5.6 and SPSS 20.0 softwares were used for statistical analysis. Results: A total of 961 strains of pathogens were isolated, 516 (53.7%) pathogens were Gram-negative bacteria, mainly 118 strains of Klebsiella pneumonia (12.3%), 68 strains of Pseudomonas aeruginosa (7.1%), 67 strains of Acinetobacter baumannii (7.0%),52 strains of Stenotrophomonas maltophilia (5.4%), 43 strains of Escherichia coli (4.5%), and 42 strains of Enterbacter cloacae (4.4%). There were 171 (17.8%) strains of Gram-positive bacteria and 274 (28.5%) fungi. The drug resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannii to carbapenem were 22.1%-31.3%. Stenotrophomonas maltophilia was sensitive to levofloxacin, compound sulfamethoxazole and minocycline. The antimicrobial resistance rates of these three enterobacteria to carbapenems, cefoperazone/sulbactam, piperacillin/tazobactam were low (<10%). The resistant Gram-positive bacteria to ticoplanin, vancomycin and linazolamide were not detected. Conclusion: The major pathogens related to lower respiratory tract infections in patients with hematological malignancies are gram-negative bacteria in our centre. Different pathogens appear different characteristics of antimicrobial resistance.

[Clinical characteristics of patients with ankylosing spondylitis and inflammatory bowel disease]

Objective: To analyze the clinical characteristics of patients with ankylosing spondylitis (AS) with inflammation bowel disease (IBD). Methods: AS patients fulfilling the 1984 modified New York diagnostic criteria were recruited in Chinese AS Prospective Imaging Cohort (CASPIC) consecutively from April 2016 to June 2017 in Chinese People's Liberation Army General Hospital by using smart management system for spondyloarthritis (SpAMS). The diagnosis of IBD was confirmed by tissue pathology via ileocolonoscopy. Demographic, clinical and biochemical data were collected. Results: In total, 893 patients with AS were recruited with the mean age 30.8 years. The majority were men (739, 82.8%). There were 64 (7.2%) patients concomitant with IBD. The mean age [(34.5±7.5) years vs. (30.5±8.8) years, P<0.001] was older and the disease duration [(10.8±6.9) years vs. (8.1±5.9) years, P=0.001] was longer in patients with IBD than patients without. Compared with patients without IBD, patients with IBD had more frequent involvement of the cervical spine [(21.9% (14/64) vs. 10.5% (87/829), P=0.006) and thoracic spine [29.7% (19/64) vs. 12.3% (102/829), P<0.001]. Uveitis [28.1% (18/64) vs. 16.4% (136/829), P=0.017] and psoriasis [7.8% (5/64) vs. 2.3% (19/829), P=0.009] were also more common in patients concomitant with IBD. In addition, patients with IBD had significantly higher scores in BASDAI (3.3±2.1 vs. 2.4±1.8, P<0.001), BASFI [2.2 (1.0,3.3) vs. 1.1(0.2,2.4), P<0.001)] and ASAS HI (7.1±4.3 vs. 5.3±3.7, P= 0.001) than patients without IBD. Conclusions: Compared with patients without IBD, AS patients concomitant with IBD have more severe disease activity and organ dysfunction. Furthermore, the uveitis and psoriasis are more frequently accompanied in AS patients with IBD.

Recognizing basal cell carcinoma on smartphone-captured digital histopathology images with a deep neural network

BACKGROUND

Pioneering effort has been made to facilitate the recognition of pathology in malignancies based on whole-slide images (WSIs) through deep learning approaches. It remains unclear whether we can accurately detect and locate basal cell carcinoma (BCC) using smartphone-captured images.

OBJECTIVES

To develop deep neural network frameworks for accurate BCC recognition and segmentation based on smartphone-captured microscopic ocular images (MOIs).

METHODS

We collected a total of 8046 MOIs, 6610 of which had binary classification labels and the other 1436 had pixelwise annotations. Meanwhile, 128 WSIs were collected for comparison. Two deep learning frameworks were created. The 'cascade' framework had a classification model for identifying hard cases (images with low prediction confidence) and a segmentation model for further in-depth analysis of the hard cases. The 'segmentation' framework directly segmented and classified all images. Sensitivity, specificity and area under the curve (AUC) were used to evaluate the overall performance of BCC recognition.

RESULTS

The MOI- and WSI-based models achieved comparable AUCs around 0·95. The 'cascade' framework achieved 0·93 sensitivity and 0·91 specificity. The 'segmentation' framework was more accurate but required more computational resources, achieving 0·97 sensitivity, 0·94 specificity and 0·987 AUC. The runtime of the 'segmentation' framework was 15·3 ± 3·9 s per image, whereas the 'cascade' framework took 4·1 ± 1·4 s. Additionally, the 'segmentation' framework achieved 0·863 mean intersection over union.

CONCLUSIONS

Based on the accessible MOIs via smartphone photography, we developed two deep learning frameworks for recognizing BCC pathology with high sensitivity and specificity. This work opens a new avenue for automatic BCC diagnosis in different clinical scenarios. What's already known about this topic? The diagnosis of basal cell carcinoma (BCC) is labour intensive due to the large number of images to be examined, especially when consecutive slide reading is needed in Mohs surgery. Deep learning approaches have demonstrated promising results on pathological image-related diagnostic tasks. Previous studies have focused on whole-slide images (WSIs) and leveraged classification on image patches for detecting and localizing breast cancer metastases. What does this study add? Instead of WSIs, microscopic ocular images (MOIs) photographed from microscope eyepieces using smartphone cameras were used to develop neural network models for recognizing BCC automatically. The MOI- and WSI-based models achieved comparable areas under the curve around 0·95. Two deep learning frameworks for recognizing BCC pathology were developed with high sensitivity and specificity. Recognizing BCC through a smartphone could be considered a future clinical choice.

[Comparison of clinical manifestations according to HLA-B(27) genotype in ankylosing spondylitis patients: real-world evidence from smart management system for spondyloarthritis]

Objective: The aim of this study was to set up a large, longitudinal and prospective database to compare the clinical manifestations in human leucocyte antigen (HLA)-B(27) positive and negative patients with ankylosing spondylitis(AS) based on real-world evidence in Chinese population. Methods: A total of 897 outpatients with confirmed AS were recruited consecutively by smart management system for spondyloarthritis (SMSP) from April 13, 2016 to June 6, 2017 in Chinese PLA General Hospital from 30 provinces and autonomous regions. 801 patients with HLA-B(27) data were included in the analysis. Demographic and clinical parameters including Bath ankylosing spondylitis disease activity index (BASDAI), Bath ankylosing spondylitis functional index (BASFI), ankylosing spondylitis disease activity score (ASDAS), arthritis, enthesitis, Bath ankylosing spondylitis metrology index (BASMI), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were compared between HLA-B(27) positive and negative groups. Results: A total of 801 patients were included in the analysis with an average age of (30.7±8.8) years. There were 659 males and 142 females and HLA-B(27) was present in 88.0%(705/801). Males were significantly more in HLA-B(27) positive patients [83.3%(587/705) vs. 75.0%(72/96); P=0.047].The average age at disease onset was (22.3±7.6)years in HLA-B(27) positive patients and (24.4±8.7) years in HLA-B(2)7 negative ones (P=0.028).There was significant difference in diagnose delay between two groups [14.3(2.5,43.6)months in HLA-B(27) positive patients vs. 20.3(5.0,67.4) months in HLA-B(27) negative ones, P=0.041]. Anterior uveitis was found to be significantly more common in HLA-B(27) positive patients [18.9% (133/705)vs.7.3%(7/96),P=0.005], and knee involvement less common in HLA-B(27) positive patients [4.0%(27/682) vs.10.0%(9/90), P=0.010], conversely. CRP[6.5(3.0, 16.4)mg/L vs. 3.5(1.6, 12.3)mg/L] and ESR[11.0(4.0, 24.0)mm/1h vs. 7.0(3.0, 16.0)mm/1h] were significantly higher in HLA-B(27) positive patients(P=0.005,0.013, respectively).But no differences in BASDAI,ASDAS,BASFI and BASMI were obtained between two groups. Conclusions: HLA-B(27) positive patients had a higher proportion of males, a younger age of onset and a greater risk for occurrence of anterior uveitis, suggesting a poorer prognosis.

[Dynamin-1-related infantile spasms: a case report and review of literature]

Objective: To analyze the clinical and gene mutation characteristics of dynamin-1 (DNM1)-related infantile spasms. Method: Clinical, laboratory and genetic data of one case of DNM1-related infantile spasms diagnosed by Xiangya Hospital in September 2015 were analyzed.Through taking "Dynamin-1" "DNM1" as key words to search at CNKI, Wanfang, PubMed and OMIM to date (April 2016), the clinical characteristics of 9 reported cases of DNM1-related epileptic encephalopathy in international literature with our case were reviewed. Result: The boy is the second child of healthy and nonconsanguineous parents.At 7 months, he started to have seizures with head dropping, and he was brought for the first time to our hospital at the age of 17 months.The patient presented with severe psychomotor retardation, epilepsy, muscular hypotonia, and electroencephalography showed hypsarhythmia.He received 28 days of adrenocorticotropic hormone (ACTH) therapy.After that, his seizures were improved with valproic acid and levetiracetam, and disappeared between 3 years and 5 months to 5 years and 5 months of age on treatment with valproic acid only.Exome-sequencing study (trios) identified novel heterozygous mutation c. 443A>G (p.Glu148Arg) in DNM1. Up to now, 9 cases of epileptic encephalopathy (infantile spasms or Lennox-Gastaut syndrome) associated with de novo DNM1 gene mutations have been reported. Conclusion: The main clinical features of DNM1 mutations include intractable seizures, intellectual disability, developmental delay, hypotonia, and developmental delay before the onset of seizures.

Analysing codon usage bias of cyprinid herpesvirus 3 and adaptation of this virus to the hosts

The codon usage patterns of open reading frames (ORFs) in cyprinid herpesvirus 3 (CyHV-3) have been investigated in this study. The high correlation between GC12 % and GC3 % suggests that mutational pressure rather than natural selection is the main factor that determines the codon usage and base component in the CyHV-3, while mutational pressure effect results from the high correlation between GC3 % and the first principal axis of principle component analysis (Axis 1) on the relative synonymous codon usage (RSCU) value of the viral functional genes. However, the interaction between the absolute codon usage bias and GC3 % suggests that other selections take part in the formation of codon usage, except for the mutational pressure. It is noted that the similarity degree of codon usage between the CyHV-3 and goldfish, Carassius auratus (L.), is higher than that between the virus and common carp, Cyprinus carpio L., suggesting that the goldfish plays a more important role than the common carp in codon usage pattern of the CyHV-3. The study of codon usage in CyHV-3 can provide some evidence about the molecular evolution of the virus. It can also enrich our understanding about the relationship between the CyHV-3 and its hosts by analysing their codon usage patterns.

miR-21 expression predicts prognosis in hepatocellular carcinoma

PURPOSE

The aim was to investigate the expression level of miR-21 in HCC tissues and its prognostic value among Asian population.

METHODS

In the present study, expression of miR-21 was evaluated by qRT- PCR in tumor and adjacent non-neoplastic tissues in 119 HCC patients. The association of miR-21 expression with clinicopathological factors and the prognosis of HCC patients was also analyzed. Survival analysis was performed using the Kaplan-Meier method and Cox's proportional hazards model.

RESULTS

We found that miR-21 expression was significantly higher in HCC tissues compared with normal adjacent liver tissues (P<0.0001). The 5-year overall survival (OS) of high miR-21 expression group was significantly shorter than that of low miR-21 expression group (40.2% vs. 70.7%; P=0.007). Moreover, the 5-year disease-free survival (DFS) of high miR-21 expression group was also significantly shorter than that of low miR-21 expression group (17.4% vs. 57.3%; P=0.001). Furthermore, in a multivariate Cox model, we found that miR-21 expression was an independent poor prognostic factor for both 5-year OS (hazards ratio [HR]=3.189, 95% confidence interval [CI]=1.911-10.012, P=0.03) and 5-year DFS (HR=5.897, CI=3.009-13.763, P<0.001) in HCC.

CONCLUSIONS

The results of the present study suggested miR-21 expression level could be a novel potential biomarker for HCC prognosis.

High expression of microRNA-130b correlates with poor prognosis of patients with hepatocellular carcinoma

Background

Whether microRNA-130b(miR-130b) can serve as a prognostic biomarker of hepatocellular carcinoma (HCC) has not been investigated. In the present study, we investigated the feasibility of miR-130b as a novel prognostic biomarker for HCC.

Methods

We retrospectively investigated 97 patients diagnosed with HCC who underwent routine curative surgery between May 2007 and July 2012. miR-130b expression in HCC tissues and paired normal adjacent liver tissues was measured by reverse transcription and real-time PCR (RT-PCR). Survival curves were plotted using the Kaplan-Meier method and differences in survival rates were analyzed using the log-rank test.

Results

miR-130b expression level was significantly higher in HCC tissues compared with normal adjacent liver tissues (P < 0.0001). The 5-year overall survival (OS) of high miR-130b expression group was significantly shorter than that of low miR-130b expression group (43.6% vs. 71.5%; P = 0.022). Moreover, the 5-year disease-free survival (DFS) of high miR-130b expression group was also significantly shorter than that of low miR-130b expression group (25.9% vs. 63.9%; P = 0.012). In a multivariate Cox model, we found that miR-130b expression was an independent prognostic factor for both 5-year OS (hazards ratio [HR] = 2.523, 95% confidence interval [CI] = 1.024-7.901, P = 0.011) and 5-year DFS (HR = 4.003, CI = 1.578-7.899, P = 0.005) in HCC.

Conclusion

The results indicated that high expression of microRNA-130b was correlated with significant characteristics of patients with HCC, and it might be useful as a novel prognostic biomarker for HCC.

Virtual Slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_160

Characterization of Bacterial Susceptibility Isolates in Sixteen Dairy Farms in Taiwan

Bacteria were isolated from dairy cows, dairy farm environments, and dairy workers in 2 geographically different areas of eastern and northern Taiwan. Isolates were evaluated for antimicrobial susceptibility and the phylogenetics of isolated Escherichia coli O157:H7 were characterized. A total of 1,346 bacteria were identified, including 226 E. coli, 30 Pseudomonas spp. (7 Pseudomonas aeruginosa), 259 other gram-negative bacteria, 271 Enterococcus spp., 314 Staphylococcus spp., 195 Streptococcus spp., and 51 other gram-positive bacteria. Among them, 88% (1,184/1,346) of the isolates were resistant to sulfadimethoxine. The percentages of gram-negative bacteria resistant to oxy-tetracycline and streptomycin were 48% (249/515) and 78% (404/515), respectively. Gram-positive bacteria isolated from eastern Taiwan, the least polluted region of Taiwan, were found to have greater antimicrobial resistance than those isolated from northern Taiwan. Two E. coli O157:H7 from 2 different geographical areas were isolated. Both were vt2-positive but vt1-negative and had phylogenetic similarities of 82 and 67%, respectively, compared with previous isolates. Information on antimicrobial susceptibility revealed from this dairy farm survey may serve as a baseline for future studies and may also highlight the need to formulate better regulation strategies for the safe use of antimicrobials on food-producing farms.

[Bepridil inhibition on the delayed rectifier K+ currents in thyroxine induced hypertrophied guinea pig ventricular myocytes]

AIM

To study the effects of bepridil on the rapidly activating component (IKr), the slowly activating component (IKs) of the delayed rectifier potassium current and the inward rectifier potassium current (IK1) in hypertrophied guinea pig ventricular myocytes.

METHODS

The whole cell patch clamp techniques were used.

RESULTS

In hypertrophied guinea pig ventricular myocytes, bepridil 30 mumol.L-1 markedly inhibited IKr and IKs (by 20.9% and 27.2% at 0 mV and mV, respectively). The effect of bepridil on IKs was larger than on IKr. Bepridil 30 mumol.L-1 also significantly inhibited the inward component of IK1 (by 15.1% at +100 mV), but the reverse potential of IK1 was unaffected. Bepridil (1-100 mumol.L-1) was shown to inhibit IKr and IKs in a concentration-dependent manner. Their IC50 were 46.7 mumol.L-1 and 23.8 mumol.L-1, respectively.

CONCLUSION

Bepridil inhibit IKr, IKs and IK1 in hypertrophied guinea pig ventricular myocytes, which may be important in understanding the antiarrhythmic effects of this drug.

Identification of a mouse brain beta-spectrin cDNA and distribution of its mRNA in adult tissues

A mouse brain beta-spectrin of cDNA was identified within a lambda Gt11 expression library using an antibody which specifically binds with the 235 kDa spectrin beta-subunit. Restriction mapping and DNA sequencing analyses of the brain cDNA revealed that this clone contained 1185 bp of sequence, of which a 999 bp single open reading frame encoding 333 amino acids was determined. The deduced amino acid sequence exhibited homology with beta-spectrins, demonstrating the characteristic 106 amino acid repeating unit. The homology between our mouse brain sequence and human RBC beta-spectrin was approximately 56% beginning at the beta 15 repeat unit and extending to the C-terminus of sequence elucidated for human RBC sequence. An additional 62 amino acids were found at the C-terminus of the 235 kDa brain beta-spectrin subunit not seen in the human RBC sequence. The approximately 1.2 Kb brain spectrin cDNA insert hybridized with a single 9 Kb mRNA transcript in various adult mouse tissues, with the most abundant hybridization demonstrated in RNA isolated from brain tissue. This mRNA was found to be present at high levels in heart tissue and at lower levels in spleen and skeletal muscle tissue. The 9 Kb mRNA was different in content and in size to mRNAs which hybridized with a cDNA encoding the mouse erythroid beta-spectrin subunit, demonstrating that the brain spectrin cDNA is a distinct gene product and represents the first known sequence of a nonerythroid beta-spectrin subunit.

Automatic end-expiratory air sampling device for breath hydrogen test in infants

An automatic electronically operated end-expiratory air sampler has been developed for use in small infants. Upon expiration, which is detected by a hot-wire sensor, a small portion of the end-expiratory air is automatically collected into a syringe mounted on a syringe driver. The sampler obtained 87% of the end-expiratory air sample. Additionally, highly reproducible and consistent results were obtained for the respiratory gases (O2, N2, CO2). The sampler has been applied for studying breath hydrogen excretion to detect lactose malabsorption. It may also be applicable to study other expiratory gases in infants.

[Interaction of component (E) with tumor cellular DNA]

Some antitumor activities of component (E), extracted from the root of Fagopynum Cymosum (TreV) meisn (FCTM), have recently been discovered in vitro and in vivo. The component (E)'s pattern of action with tumor cellular DNA at the molecular pharmacological level was investigated by macromolecular synthesis experiment (MSE) and human DNA interaction HDI system established in our laboratory. The experiments demonstrated that, in vitro, the agent could markedly inhibit incorporation of H3-TdR into the cellular DNA, and the IC50 in P388 and SGC-7901 was 17.86 micrograms/ml and 110.4 micrograms/ml, respectively. The agent, at level of mg/ml, could produce an intercalation reversion pattern with DNA within a short time (2 hours). But when the interval was prolonged for over 4 hours, the pattern of action changed to intercalation irreversible pattern. According to these observations, the authors infer that component (E) interacts with DNA in two ways-directly and indirectly. The indirect action, especially in low concentrations, probably plays the major role. The authors have also compared the interaction of component (E) with those of components (CD1) and (CB3) extracted from FCTM by the same method and found that component (E) is the most active agent against the DNA of cancer cells among the extracts from FCTM.

Pseudo-on-line fast response microvessel dimensions video graphic recorder with electrical signal output

The present article describes a new method of microvessel dimensions measurement in which a writing oscilloscope is used to continuously and graphically record the microvessel video signal from television microscopy at a fast rate of 50 records per second. Dimensions of interest, such as the microvessel red blood cell flux diameter, are then easily marked out manually from the graphic records and a dynamic electrical signal proportional to the dimensions is generated. The signal is then recorded on one channel of a multichannel voltage recorder and is synchronised with other experimental signals which have previously been recorded on-line during the experiment. The result is that the dimension signal appears to have been recorded on-line during the experiment as well. This is desirable for electronic signal correlation and processing. This method is useful when poor experimental conditions, commonly encountered, make automatic recording of microvessel dimension unsatisfactory and manual inspection and processing become necessary.