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Purpose: The study aimed to establish a mouse model of Graves' disease (GD) with Graves' orbitopathy (GO; GD + GO) that can represent the clinical disease characteristics., Methods: A eukaryotic expression plasmid of insulin-like growth factor 1 receptor (IGF-1R) α subunit (pcDNA3.1/IGF-1Rα) and a thyrotropin receptor (TSHR) A subunit plasmid (pcDNA3.1/TSHR-289) were injected in female BALB/c mice followed by immediate electroporation to induce a GD + GO model. Grouping was performed according to the frequency of injection (2- to 4-week intervals) and type of injected plasmids: T: pcDNA3.1/TSHR-289( +), I: pcDNA3.1/IGF-1Rα( +), or co-injection T + I: pcDNA3.1/TSHR-289( +) and pcDNA3.1/IGF-1Rα( +). Serum TSH, T4, TSAb, TSBAb, body weight, and blood glucose levels were evaluated. Thyroid 99m TcO 4- imaging and retrobulbar magnetic resonance imaging (MRI) were performed, and bilateral eye muscle volumes were measured. Immunohistochemistry and hematoxylin-eosin staining were performed on the relevant tissues, and semi-quantitative analysis was performed., Results: A total of 60% of mice (3/5, one mouse died) in the T group developed GD + GO. In the T + I group, 83.3% of mice (5/6) developed GD + GO. Mice in the I group did not develop GD. Compared with the control group, serum T4, TSAb, and TSBAb of the mice in the GD + GO model groups were increased to varying degrees (P < 0.05), and serum TSH and body weight were significantly lower compared to the control group (P < 0.05). The thyroid uptake capacity of 99m TcO 4- and the volume of eye muscle of mice in the GD + GO group were significantly higher compared to the control group (P < 0.05). The thyroid and retrobulbar muscles of these mice showed varying inflammatory infiltration and interstitial muscle edema. The severity of GD + GO in the co-injection group was not related to injection frequency; however, GD and ocular signs in co-injection mice were more severe compared to the T group., Conclusions: We successfully induced a GD + GO mouse model by a repeated co-injection of pcDNA3.1/IGF-1Rα and pcDNA3.1/TSHR-289 plasmids. Injection of pcDNA3.1/IGF-1Rα alone failed to induce GD. Co-injection of two plasmids induced more severe GD + GO than pcDNA3.1/TSHR-289( +) alone., (© 2024. The Author(s), under exclusive licence to Italian Society of Endocrinology (SIE).)

Purpose: Incisional hernia (IH) is one of the most common complications after abdominal surgeries and may bring great suffering to patients. This study aims to evaluate the global trends in IH research from 2003 to 2023 and visualize the frontiers using bibliometric analysis., Methods: The literature search was conducted on the Web of Science for IH studies published from 2003 to 2023 and sorted by citation frequency. The top 100 most-cited articles were analyzed by the annual publication number, prolific countries and institutions, influential author and journal, and the number of citations through descriptive statistics and visualization., Results: The top paper was cited 1075 times and the median number of citations was 146. All studies were published between 2003 and 2019 and the most prolific year was 2003 with 14 articles. Jeekel J and Rosen M were regarded as the most productive authors with ten articles each and acquired 2738 and 2391 citations, respectively. The top three institutions with the most productive articles were Erasmus Mc, Carolinas Med Ctr, and Univ Utah, while the top three countries were the United States, Netherlands and Germany. The most frequent keyword was "incisional hernia" with 55 occurrences, followed by "mesh repair", "randomized controlled trial", and "polypropylene"., Conclusion: The 100 most-cited papers related to IH were published predominantly by USA and European countries, with randomized controlled trial (RCT) and observational study designs, addressing topics related to risk factors, complications, mesh repair, and mesh components., (© 2023. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Purpose: Obesity and a high body mass index (BMI) are considered as risk factors for abdominal wall hernia (AWH). However, anthropometric measures of body fat distribution (BFD) seem to be better indicators in the hernia field. This Mendelian randomization analysis aimed to generate more robust evidence for the impact of waist circumstance (WC), body, trunk, arm, and leg fat percentages (BFP, TFP, AFP, LFP) on AWH., Methods: A univariable MR design was employed and the summary statistics allowing for assessment were obtained from the genome-wide association studies (GWASs). An inverse variance weighted (IVW) method was applied as the primary analysis, and the odds ratio value was used to evaluate the causal relationship between BFD and AWH., Results: None of the MR-Egger regression intercepts deviated from null, indicating no evidence of horizontal pleiotropy (p > 0.05). The Cochran Q test showed heterogeneity between the genetic IVs for WC (p = 0.005; p = 0.005), TFP (p < 0.001; p < 0.001), AFP-L (p = 0.016; p = 0.015), LFP-R (p = 0.012; p = 0.009), and LFP-L (p < 0.001; p < 0.001). Taking the IVW random-effects model as gold standard, each standard deviation increment in genetically determined WC, BFP, TFP, AFP-R, AFP-L, LFP-R, and LFP-L raised the risk of AWH by 70.9%, 70.7%, 56.5%, 69.7%, 78.3%, 87.7%, and 72.5%, respectively., Conclusions: This study proves the causal relationship between AWH and BFD, attracting more attention from BMI to BFD. It provides evidence-based medical evidence that healthy figure management can prevent AWH., (© 2024. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Purpose: Incisional hernia (IH) is a common secondary ventral hernia after abdominal incisions and there is still little reliable evidence to predict and prevent IH. This study aimed to estimate risk factors of its incidence, especially concentrating on blood results., Methods: 96 patients received midline laparotomy for gastrointestinal benign diseases and suffered from IH were enrolled in the IH group. A control group of 192 patients were randomly selected from patients underwent midline laparotomy for gastrointestinal benign diseases without IH., Results: Patients in the IH group exhibited higher age (P < 0.001), BMI (P < 0.001), hernia history (P = 0.001) and laparotomy history (P < 0.001). Rate of coronary heart disease (P = 0.046), hypertension (P < 0.001), diabetes (P = 0.008), incisional infection (P = 0.004) and emergency surgery (P = 0.041) were also higher in the IH group. Patients with IH had lower levels of Hb (P = 0.002), TP (P = 0.013), ALB (P < 0.001), A/G (P = 0.019), PA (P < 0.001), HDL-C (P = 0.008) and ApoA1 (P = 0.005). Meanwhile, patients in the control group bore lower levels of LDH (P = 0.008), GLU (P = 0.007), BUN (P = 0.048), UA (P = 0.021), TG (P = 0.011), TG/HDL-C (P = 0.002), TC/HDL-C (P = 0.013), ApoB/ApoA1 (P = 0.001) and Lp(a) (P = 0.001). A multivariate logistic regression revealed that high BMI, laparotomy history, incisional infection, decreased PA, elevated levels of UA, Lp(a) and ApoB/ApoA1 were independent risk factors of IH., Conclusion: This is the first study to reveal the relationship between IH and serum biochemical levels, and give a prediction through the nomograph model. These results will help surgeons identify high-risk patients, and take measures to prevent IH during the perioperative period., (© 2023. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

This study aimed to explore the biological role and mechanism underlying the effects of colon cancer-associated transcript 2 (CCAT2), a long noncoding RNA (lncRNA) in human laryngeal squamous cell carcinoma (LSCC). CCAT2 expression levels in clinical LSCC samples and TU-212 cell line were evaluated by quantitative real-time PCR. The correlation of CCAT2 expression level with clinical-pathological characteristics of patients and their prognosis was analyzed. The functional role of CCAT2 in human LSCC was assessed by Cell Counting Kit-8, Transwell assay, flow cytometric analysis, and LSCC xenograft experiment in vivo. The expression of potential targeted proteins was detected by Western blotting and immunohistochemistry. We found that expression of CCAT2 was significantly elevated in LSCC tissues and TU-212 cells (p<0.05). Survival analysis showed that LSCC patients with high expression of CCAT2 had a shorter 5-year overall survival rate than those with low expression (p<0.05). In addition, CCAT2 silencing with short hairpin RNA significantly decreased the proliferative and invasive potential of TU-212 cells (p<0.05) and promoted their apoptosis. In Nude mice, CCAT2 knockdown suppressed the growth of tumor and decreased its volume and weight in comparison with the controls (p<0.05). In TU-212 cells, CCAT2 silencing with short hairpin RNA significantly down-regulated the expression of β-catenin and CDK8 (p<0.05). Thus, knockdown of CCAT2 suppresses proliferation and invasion of the cells and inhibits Wnt/β-catenin signaling pathway in LSCC, which indicates novel therapeutic targets and prognostic indicators in patients with LSCC., (© 2023. Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: To determine the association between serum periostin and the presence of diabetic retinopathy (DR)., Methods: Serum periostin was detected in 114 healthy subjects, 122 patients with type 2 diabetes mellitus (T2DM) and 159 patients with DR and compared among groups. Clinical data and other laboratory measurements such as glycated hemoglobin (HbA1c), lipid profiles, serum creatinine (Cr) and high-sensitivity CRP (hsCRP) were also collected and compared among groups. For subgroup analysis, patients with DR were divided into a non-proliferated diabetic retinopathy (NPDR) group and a proliferated diabetic retinopathy (PDR) group. Multivariate analysis was performed using logistic regression models., Results: The serum periostin level was significantly higher in patients with diabetic retinopathy compared with healthy subjects and patients with T2DM (both P < 0.001, respectively). Also, the periostin level was significantly higher in the PDR group compared to the NPDR group (P = 0.044). Multivariate logistic regression revealed that serum periostin was independently associated with the presence of DR in patients with T2DM (P < 0.001). The receiver operating characteristic (ROC) curves for DR development using serum periostin showed that the area under the receiver operating characteristic curves (AUC) was 0.838 (P < 0.001)., Conclusions: The current study demonstrated that serum periostin is significantly associated with the presence of DR in patients with T2DM and is an independent risk factor of DR.

Background: The development of laparoscopic processus vaginalis repair has provided an alternative approach to the management of inguinal hernia and hydroceles in children. Here we describe our new technique for laparoscopic extraperitoneal ligation of processus vaginalis with subumbilical single-port using a modified Kirschner pin., Methods: A 5-mm trocar for an operative laparoscope was placed through an infraumbilical incision. A Kirschner pin with a hole in one flat terminal was inserted at the point of the internal inguinal ring. The processus vaginalis was closed extracorporeally by a non-absorbable suture, which was introduced into the abdomen through the Kirschner pin performing dissection within the extraperitoneal space in a series of movements. When a contralateral patent processus vaginalis is present, laparoscopic-assisted extracorporeal ligation is performed during the same operation., Results: Between September 2010 and September 2012, 211 children (130 cases of inguinal hernia and 81 cases of hydrocele) underwent processus vaginalis repair using this novel technique. A contralateral patent processus vaginalis was present and thus simultaneously closed in 20 patients with unilateral inguinal hernias and 12 patients with unilateral hydroceles. The mean operative time was 18 min (8-35 min). The mean follow-up period is 12 months (range 5-24 months), and no recurrence and complications has been observed to date., Conclusions: This article describes a unique technique of extracorporeal circuit ligation of processus vaginalis using a minimally invasive technique as afforded by a reused modified Kirschner pin. Single-port laparoscopic processus vaginalis repair using this instrument is feasible and seems to be safe.

To analyze immunodominant regions of leukotoxin protein of Fusobacterium necrophorum strain H05, a series of truncated forms of leukotoxin gene were expressed in Escherichia coli using the vector pGEX-6p-1 or pPROEX HTa. The results of SDS-PAGE showed the truncated forms PL1, PL2, PL4, and PL5 were expressed in Escherichia coli using the vector pGEX-6p-1, and the truncated forms PL3 was expressed in Escherichia coli using the vector pPROEX HTa. These recombinant proteins were able to react with antisera against Fusobacterium necrophorum strain A25. In five recombinant proteins, the recombinant proteins PL1, PL3 and PL4 as vaccine were able to elicit formation of the better protective effects on mice against infection of Fusobacterium necrophorum strain A25.

Genetic instability could be provoked as an unintended consequence of genetic engineering in plants. Here, we report that the rice endogenous long terminal repeat (LTR) retrotransposon Tos17 was transpositionally activated only in transgenic calli and their regenerated plants produced by biolistic transformation in rice (Oryza sativa L.) ssp. japonica cv. Matsumae. Moreover, the transpositional activity of Tos17 was sustained after plant regeneration in the T0 generation, and produced new germinal insertions. In contrast, the element remained totally quiescent in calli and regenerated plants from tissue culture of this genotype. Nonetheless, transcriptional induction and cytosine demethylation of Tos17 were found to have occurred with no significant difference in both kinds of calli, tissue culture alone and transgenic. This suggests that callus culture is likely to have played an important role in destabilizing Tos17 in the direction towards transpositional activation, but that biolistic transformation is the direct causal factor.

We have reported recently that tissue culture induced a high level of genetic variation at the primary nucleotide sequence in regenerants of medicinal plant Codonopsis lanceolata. It is not known, however, whether epigenetic variation in the form of alteration in DNA methylation also occurred in these plants. Here, we investigated possible alterations in level and pattern of cytosine methylation at the CCGG sites in the same set of regenerants relative to the donor plant, by the MSAP method employing a pair of isoschizomers, HpaII and MspI, which recognize the same restriction site but are differentially sensitive to cytosine methylation at the CCGG sites. A total of 1,674 MSAP profiles were resolved using 39 primer combinations. Of these, 177 (10.5%) profiles were polymorphic among the regenerants and/or between the regenerant(s) and the donor plant, in EcoRI + HpaII or EcoRI + MspI digest but not in both, indicating alteration in cytosine methylation patterns of specific loci, though their estimated total level of methylation remained more or less the same as the donor plant. Gel blot analysis validated most of the variant MSAP profiles as bona fide alteration in methylation patterns. Correlation analysis between the MSAP data and the previously reported ISSR and RAPD data revealed significant correlations, suggesting their possible intrinsic interrelatedness. Thirty-seven typical variant MSAP profiles were isolated and sequenced, of which 5 showed significant homology to known-function genes, 2 to chloroplast sequences, whilst the rest 30 did not find a match in the database.

Avian influenza (AI) is a serious infectious disease caused by avian influenza virus (AIV) belonging to type A Orthomyxovirus. In the present study, we developed an indirect enzyme-linked immunosorbent assay (ELISA) employing E. coli-expressed full-length nucleoprotein (NP) of H9N2 avian influenza virus for the detection and quantification of antibodies against AIV nucleoprotein. The NP-ELISA was compared with the AI agar gel propagation (AGP) test, haemagglutination inhibition (HI) test, and IDEXX-FlockChek ELISA using 263 sera. The NP-ELISA was significantly more sensitive than the AGP and HI tests, and showed 96.2% agreement ratio with IDEXX-FlockChek ELISA. With results obtained using the NP-ELISA, an ELISA titre (ET) prediction equation, with which the ELISA titres of a flock or individual chickens can be determined, was derived from a positive/negative (P/N) ratio standard curve. The NP-ELISA enables an alternative rapid serological diagnosis and is suitable for influenza A antibody screening, especially in species that harbour several influenza subtypes.

Dominant markers have been commonly used in mapping quantitative trait loci (QTLs) in outcrossing species, in which not much prior genome information is available. But the dominant nature of these markers may lead to reduced QTL mapping precision and power. A new statistical method is proposed to incorporate growth laws into a QTL mapping framework, under which the use of the efficiency of dominant markers can be increased. This new method can be used to identify specific QTLs affecting differentiation in growth trajectories, and further estimate the timing of a QTL to turn on, or turn off, affecting growth during the entire ontogeny of a species. Using this method based on dominant markers we have successfully mapped a QTL for stem height growth trajectories to a linkage group in a forest tree. The implications of this method for the understanding of the genetic architecture of growth using dominant markers are discussed.

A novel intact circular dsDNA supercoil is proposed as an alternative to the conventional DNA supercoil, so that the two complementary strands of ssDNA circles are separable without any covalent bond breakage. This new structure can be visualized by using two tubings: one black and one clear. Twist the black tubing a number of times and connect its two ends. Do the same for the clear tubing. Then wrap the two tubings together. This forms the separable or novel supercoil. On the other hand, the conventional supercoil can be modeled by twisting the black and clear tubings together and then connect their respective ends, so that the two tubings are not separable unless one of them is cut. Experimentally, in the absence of any enzyme, many intact plasmid dsDNA circles give two bands on agarose gel electrophoresis under a certain given condition, while the same plasmid molecules after cutting once by a restriction enzyme give only one band under the same condition. In the case of intact pUC19 plasmids, these two bands can then be recovered and sequenced separately, using two primers in opposite directions. Each band gives mostly one sequence which is complementary to that of the other band. The combination of the above theoretical model and experimental results strongly suggests that there is an alternative structure of DNA which does not have the usual difficulty of unwinding, rewinding and requiring numerous covalent bond breakages and ligations during semiconservative.

We have developed a reproducible biolistic procedure for the efficient transformation of embryogenic suspension cells of an improved aromatic Indica rice variety, Pusa Basmati 1. The β-glucuronidase gene was used to assay transient transformation; other plasmids carrying either a potato protease inhibitor 2 (Pin2) gene, or a late embryogenesis-abundant protein (LEA3) gene from barley, were used for the optimization of biolistic process and transgenic plant production. After optimization of the procedure, over 600 transient transformants and at least five fertile plants showing integrative transformation were obtained per bombarded filter. At least 30% of the plants were derived from independent transformation events. The new improved procedure involves the use of a reporter gene or other useful genes driven by the strong rice actin 1 gene (Act1) promoter, osmotic pre-conditioning of cells for 24 h on medium supplemented with 0.25 M mannitol prior to bombardment, use of gold particles for DNA delivery, and use of plant regeneration medium with high (1.0%) agarose concentration.

The genetic causes of heterosis in tree growth were investigated by a comparative genetic analysis of intra- and inter-specific crosses derived from Populus tremuloides and P. tremula. A new analytical method was developed to estimate the effective number of loci affecting a quantitative trait and the magnitudes of their additive and dominant effects across loci. The method combines the assumption of multiple alleles, as frequently found in outcrossing species, and the family structure analysis at different hierarchical levels. During the first 3 years of growth, interspecific hybrids displayed strong heterosis in stem growth, especially volume index, over intraspecific hybrids. By a series of joint analyses on the combining ability and the genetic component, we found that F1 heterosis might be due to overdominant interaction between two alleles, one from the P. tremuloides parent and the other from the P. tremula parent, at the same loci. This inference was derived from the finding that heterozygotes, newly formed through species combination, showed much greater growth than the heterozygotes from intraspecifc crosses at a reference locus. Heterosis in aspen growth appeared to be under multi-genic control, with a slightly larger number of loci for stem diameter and volume (9-10) than for height (6-8). For traits with non-significant heterosis, such as stem allometry and internode number and length, the number of underlying loci seemed to be much fewer (3-4). While additive effects appeared to influence seedling traits collectively across loci, a few major dominant loci had much larger effects on stem growth.

Embryogenic suspension cells of two commercially cultivated aromatic Indica rice varieties, Basmati 385 and Pusa Basmati 1, were cryopreserved using a simple one-step freezing procedure that does not require a controlled-rate freezer. The procedure involves osmotic pre-conditioning of cells with mannitol, addition of a cryoprotectant solution consisting of sucrose, dimethyl sulfoxide, glycerol, proline, and modified R2 medium, cooling to -25°C for 2 h in a freezer, and then storage in liquid nitrogen. After rapid thawing at 45°C, these cultures showed post-thaw cell viability of 5.6 to 10.5% and formed actively dividing, readyto-use cell suspensions in 20-35 d when cultured directly into liquid medium. Plants were regenerated from cell clumps as well as from colonies formed by protoplasts that were isolated from suspension cells re-established from cryopreserved cells, with frequencies higher (54-98%) than, or comparable to, those obtained from three to four-month-old original non-frozen cell cultures. Cell viability and regeneration frequencies of post-thawed Pusa Basmati 1 cultures were similar to those obtained from the suspension cells cryopreserved using the conventional slow-freezing procedure which involves pre-freezing cells to -40°C at the rate of -0.2°C per min prior to immersion in liquid nitrogen. In Basmati 385, however, cells frozen at --25°C showed lower post-thaw cell viability than those preserved using the slow-freezing procedure, but these cells produced cell suspensions that had greater shoot morphogenetic potential. The study indicates the beneficial effect of this simple freezing procedure, not only for preserving desirable cultured cells but also for an enrichment of embryogenic cells.

Frequency of regeneration of fertile plants from cell suspensions was significantly increased using water stress treatments in two commercially cultivated Indian aromatic rice varieties, Basmati 385 and Pusa Basmati 1. The water stress treatments included the use of 1.0% (w/v) agarose instead of 0.5% (w/v) for medium solidification, inclusion of mannitol (0.1, 0.2 and 0.4 M) in regeneration medium, or 24 h partial desiccation of calli. When the agarose concentration of the regeneration medium was increased from 0.5% to 1.0% (w/v), the frequency of shoot formation in Pusa Basmati 1 from cell suspension-derived calli increased by over eightfold, to 86%. Mannitol, at 0.1 to 0.2 M concentration, stimulated the frequency of shoot regeneration in Pusa Basmati 1 by fivefold but had no effect in Basmati 385. Mannitol at 0.4 M concentration completely inhibited shoot regeneration but promoted embryogenesis. These calli regenerated shoots with greater frequencies when transferred to mannitol-free medium. Partial desiccation of rice calli resulted in an up to threefold increase in the shoot regeneration frequency. Best regeneration frequencies (54-98%) were obtained when 24 hdesiccated calli were grown on regeneration medium with 1.0% (w/v) agarose. A similar stimulatory effect of water stress on plant regeneration was observed in another Indica rice variety, IR43, and a Japonica rice variety, Taipei 309.

Interspecific hybridization has played a critical role in tree evolution and breeding. The findings of triploidy in forest trees stimulate the development of a quantitative genetic model to estimate the nature of gene action. The model is based on clonally replicated triploid progenies derived from a two-level population and individual-within-population mating design in which offspring have a double dose of alleles from the parent and a single dose of alleles from the other parent. With the same genetic assumptions of a diploid model, except non-Mendelian behavior at meiosis, and the experimental variances estimated from a linear statistical model, total genetic variances in the triploid progenies are separated into additive, dominance, and epistatic components. In addition, by combining the new model with the already existing model based on disomic expression, the partitioning of additive, dominant, and epistatic variances can be obtained for a mixed diploid/triploid F1 progeny population. This paper provides an alternative technique to study the modes of quantitative inheritance for outcrossing, long-lived forest trees in which inbred lines cannot be easily generated. The accuracy for estimating gene action using this technique is discussed.

One approach to gain an insight into the genetics of tree architecture is to make use of morphologically divergent parents and study their segregating progeny in the F2 and backcross (B1) generations. This approach was chosen in the present study in which material of a three-generation pedigree growing side by side in a replicated plantation, was analyzed. The pedigree included Populus trichocarpa (T) and P. deltoides (D) parents, their F1 and F2 hybrids and their B1 hybrids to the D parent. The trees were grown in the environment of the T parent and measured for the first 2 years of growth. Nine quantitative traits were studied at the stem, branch and leaf levels of tree architecture, in which the original parents differed. Strong F1 hybrid vigor relative to the better parent (T) was expressed in growth and its components. Most quantitative traits in the F2 and B1 hybrids were intermediate between the T and D parents but displayed a wide range of variation due to segregation. The results from the analysis of variance indicated that all morphometric traits were significantly different among F2 and B1 clones, but the B1 hybrids were more sensitive to replicates than the F2. Broad-sense heritabilities (H (2)) based on clonal means ranged from moderately high to high (0.50-0.90) for the traits studied, with H (2) values varying over age. The H (2) estimates reflected greater environmental "noise" in the B1 than in the F2, presumably due to the greater proportion of maladaptive D alleles in those hybrids. In both families, sylleptic branch number and length, and leaf size on the terminal, showed strong genetic correlations with stem growth. The large divergence between the two original parents in the traits studied, combined with the high chromosome number in Populus (2n=38), makes this pedigree well suited for the estimation of the number of quantitative trait loci (QTLs) underlying quantitative variation by Wright's biometric method (1968). Variation in several traits was found to be under the control of surprisingly few major QTLs: 3-4 in 2nd-year height and diameter growth, a single QTL in stem diameter/height ratio.

We previously demonstrated that human tracheobronchial epithelial (TBE) cells synthesize mucin and form mucous granules in culture when they are maintained on a collagen gel (CG) substratum, but not on a plastic tissue culture surface or a thin collagen-coated surface (Wu et al., Am. J. Respir. Cell Mol. Biol., 3:467-478; 1990). This observation led us to examine the effects of CG thickness on cell growth and differentiation in primary human/monkey TBE cell cultures. Using the same CG preparation, culture dishes with different thicknesses of CG substratum were prepared. In general, equivalent degrees of cell attachment and proliferation were observed in all cultures maintained on a collagen gel, independent of the thicknesses of CG substratum. However, a greater degree of mucin synthesis and secretion by the cells was observed as the thickness of the CG substratum was increased. Cultures maintained on a thick collagen gel (1 mm) exhibited greater apical membrane complexity, more pseudostratification, and more mucous granules than did cultures maintained on a thin CG substratum. The optimal culture surface for airway mucous cell differentiation contains more than 1-mm thickness of collagen gel substratum.

We previously demonstrated that human tracheobronchial epithelial (TBE) cells synthesize mucin and form mucous granules in culture when they are maintained on a collagen gel (CG) substratum, but not on a plastic tissue culture surface or a thin collagen-coated surface (Wu et al., Am. J. Respir. Cell Mol. Biol., 3:467-478; 1990). This observation led us to examine the effects of CG thickness on cell growth and differentiation in primary human/monkey TBE cell cultures. Using the same CG preparation, culture dishes with different thicknesses of CG substratum were prepared. In general, equivalent degrees of cell attachment and proliferation were observed in all cultures maintained on a collagen gel, independent of the thicknesses of CG substratum. However, a greater degree of mucin synthesis and secretion by the cells was observed as the thickness of the CG substratum was increased. Cultures maintained on a thick collagen gel (1 mm) exhibited greater apical membrane complexity, more pseudostratification, and more mucous granules than did cultures maintained on a thin CG substratum. The optimal culture surface for airway mucous cell differentiation contains more than 1-mm thickness of collagen gel substratum.

Suspension cells of Oryza sativa L. (rice) were transformed, by microprojectile bombardment, with plasmids carrying the coding region of the Streptomyces hygroscopicus phosphinothricin acetyl transferase (PAT) gene (bar) under the control of either the 5' region of the rice actin 1 gene (Act1) or the cauliflower mosaic virus (CaMV) 35S promoter. Subsequently regenerated plants display detectable PAT activity and are resistant to BASTA(TM), a phosphinothricin (PPT)-based herbicide. DNA gel blot analyses showed that PPT resistant rice plants contain a bar-hybridizing restriction fragment of the expected size. This report shows that expression of the bar gene in transgenic rice plants confers resistance to PPT-based herbicide by suppressing an increase of ammonia in plants after spraying with the herbicide.

Repetitive DNA sequences in the genus Oryza (rice) represent a large fraction of the nuclear DNA. The isolation and characterization of major repetitive DNA sequences will lead to a better understanding of rice genome organization and evolution. Here we report the characterization of a novel repetitive sequence, CC-1, from the CC genome. This repetitive sequence is present as long tandem arrays with a repeat unit 194 bp in length in the CC-diploid genome but 172 bp in length in the BBCC and CCDD tetraploid genomes. This repetitive sequence is also present, though at lower copy numbers, in the AA and BB genomes, but is absent in the EE and FF genomes. Hybridization experiments revealed considerable differences both in copy numbers and in restriction fragment patterns of CC-1 both between and within rice species. The results support the hypothesis that the CC genome is more closely related to the AA genome than to the BB genome, and most distantly related to the EE and FF genomes.

Endralazine, a novel vasodilator related to hydralazine, exhibits a longer half-life and is only minimally influenced by acetylator status. The antihypertensive action of once daily endralazine has been studied in 17 patients previously controlled with an antihypertensive regimen which included hydralazine and a beta-blocker. Hydralazine was discontinued but other medications were unchanged. Pre-study dosage of hydralazine ranged from 25 mg b.i.d. to 50 mg g.i.d., mean daily dose 126.5 mg. Endralazine was started at a dose of 10 mg o.d. and increased by 10 mg to a maximum of 40 mg o.d. until seated DBP was controlled below 95 mmHg. All 17 patients completed the study. Seated BP significantly decreased from 147.5/99.7 to 133.8/83.9 and standing BP from 145.8/99.2 to 133.6/87.3 mmHg. Ten patients (59%) were successfully controlled with endralazine once daily but 7 patients required twice daily dosage schedules because of lack of BP control at 24 h after dosing or excessive hypotension shortly after dosing. Other adverse effects were headache, palpitations and fatigue. There was a statistically insignificant average weight gain of 1 kg but pedal edema was not observed. Endralazine is an effective antihypertensive agent with adverse symptoms similar to those experienced with hydralazine.

Rice is one of the most important crops in the world with 35% of the total population (over two billion people) depending on it as their source of food. It is therefore essential to develop efficient methods for the transformation and regeneration of rice plants in order to delineate the exact regulatory sequences responsible for gene expression and to transfer beneficial genes into this plant. Here, for the first time, we present definitive evidence for the regeneration of a large number of transgenic rice plants after introduction of the bacterial β-glucuronidase gene into rice protoplasts. The presence of integrated copies of this gene was detected in the genome of transgenic plants by DNA hybridization analysis. Furthermore, under the control of regulatory regions from a maize alcohol dehydrogenase sequence, β-glucuronidase gene expression was detected in the roots of transgenic plants. This expression was stimulated up to six fold under anaerobic conditions.

Repetitive DNA sequences are useful molecular markers for studying plant genome evolution and species divergence. In this paper, we report the isolation and characterization of four genome-type specific repetitive DNA sequences in the genus Oryza. Sequences specific to the AA, CC, EE or FF genome types are described. These genome-type specific repetitive sequences will be useful in classifying unknown species of wild or domestic rice, and in studying genome evolution at the molecular level. Using an AA genome-specific repetitive DNA sequence (pOs48) as a hybridization probe, considerable differences in its copy number were found among different varieties of Asian-cultivated rice (O. sativa) and other related species within the AA genome type. Thus, the relationship among some of the members of AA genome type can be deduced based on the degree of DNA sequence similarity of this repetitive sequence.