The maximal number of these constituents depends both on genetic

The maximal number of these constituents depends both on genetic and environmental factors. Accounting for logistical structure-dynamics interrelations, equations can be formulated to describe the bimodal growth curves of very different plants. The reproduction of the S-bended growth curves verifies that the relaxation

modes with a broad structure-controlled distribution freeze successively until finally growth is fully blocked thus bringing about “continuous solidification”.”
“The ongoing spread of tuberculosis (TB) in poor resource countries and the recently increasing incidence in high resource countries lead to the need of updated knowledge for clinicians, particularly for pediatricians. The purpose of this article is to provide an overview on the most important AZD1480 clinical trial peculiarities of TB in children. Children are less contagious than adults, but the risk of progression to active disease is higher

in infants and children as compared to the subsequent ages. Diagnosis of TB in children is more difficult than in adults, because few signs are associated with primary infection, interferon-gamma release assays and tuberculin skin test are less reliable in younger children, M. tuberculosis is more rarely detected in gastric aspirates than in smears SB202190 in adults and radiological findings are often not specific. Treatment of latent TB is always necessary in young children, whereas it is recommended in older children, as well as in adults, only in particular conditions. Antimycobacterial drugs are generally better tolerated in children as compared to adults, but off-label use of second-line antimycobacterial drugs is increasing, because of spreading of multidrug

resistant TB worldwide. Given that TB is a disease which often involves more than one member in a family, a closer collaboration is needed between pediatricians and clinicians who take care of adults.”
“Four model thiosemicarbazide anion chemosensors containing three N-H bonds, substituted with phenyl and/or 4-nitrophenyl units, were synthesised and studied for their anion binding abilities with hydroxide, fluoride, acetate, dihydrogen phosphate and chloride. The anion binding properties were studied in DMSO AG-014699 DNA Damage inhibitor and 9:1 DMSO-H2O by UV-visible absorption and H-1/C-13/N-15 NMR spectroscopic techniques and corroborated with DFT studies. Significant changes were observed in the UV-visible absorption spectra with all anions, except for chloride, accompanied by dramatic colour changes visible to the naked eye. These changes were determined to be due to the deprotonation of the central N-H proton and not due to hydrogen bonding based on H-1/N-15 NMR titration studies with acetate in DMSO-d(6)-0.5% water. Direct evidence for deprotonation was confirmed by the disappearance of the central thiourea proton and the formation of acetic acid.

No additional analgesics were required The patient was discharge

No additional analgesics were required. The patient was discharged on postoperative

day 1, resumed normal activities in smaller than 24 hours, and remained satisfied with the pain management for 5 days. Discussion. TAP infiltration of liposome bupivacaine was associated with improvement in postsurgical pain control, eliminated the need for additional opioids, and reduced the length of hospital stay from the usual 3 days to smaller than 24 hours. Conclusions. Liposome bupivacaine administered via TAP infiltration shows potential as part of a multimodal analgesic regimen in laparoscopic cholecystectomy.”
“In cattle, nearly all heifers born co-twin to a male are freemartins, XX/XY chimeras that exhibit a characteristic masculinized phenotype. However, in sheep, while litters containing males and females are common, freemartins are relatively rare. The primary aim of this study was to determine the frequency and features of XX/XY chimerism in female Rideau Arcott sheep. Also, breeding records were used to investigate the effect of litter size and sex ratios, as well as the genetic basis of the condition. Finally, the migration and transcriptional competence of VS-6063 in vitro cells of the opposite sex in the XX/XY female and male chimeras

was explored. Genomic DNA (gDNA) from peripheral blood cells of ewes was screened by PCR for the malespecific SRY gene. Of 230 lambs screened, 10 were identified as chimeras. Litter size and sex ratio showed no statistically significant effect on the frequency of chimerism. PCR and FISH

analysis confirmed the presence of opposite sex cells in female and male chimeras, and in the case of ewes, their migration to tissues other than blood. Transcriptional activity of SRY and AMH was detected in gonads of ewes, whereas XIST expression was detected in white blood cells of chimeric rams. It was concluded that the frequency of sex chromosome chimerism in Rideau Arcott sheep is estimated at 4.35%, with no significant effect of litter size and sex ratio. Moreover, as it was shown that opposite sex cells can migrate to tissues other selleck inhibitor than blood and be transcriptionally active in chimeric sheep, we speculate on the role they can play in these animals. Copyright (C) 2008 S. Karger AG, Basel.”
“Noonan syndrome (NS) and related disorders are caused by mutations in various genes encoding molecules involved in the RAS-MAPK signalling cascade. There are strong genotype-phenotype correlations. BRAF is the major gene for cardio-facio-cutaneous syndrome (CFCS), and usually patients with a BRAF mutation have significant cognitive impairment. We report on a patient with LEOPARD syndrome and normal intelligence who was found to carry a novel sequence change in BRAF The mutation p.L245F was demonstrated to be de novo with no evidence of somatic mosaicism.

Methods: Parents of children with ADHD beginning treatment wi

\n\nMethods: Parents of children with ADHD beginning treatment with LDX voluntarily completed surveys through an automated telephone system or the Internet before and 6 weeks after LDX treatment

initiation. Prescribing physicians received individual reports of the responses for each survey completed by their patients’ parents. All patients whose parents completed both baseline and 6 week surveys were included in the analyses. Subgroup analyses were conducted for those previously treated with medications to treat ADHD, including mixed amphetamine salts-extended Vorinostat cell line release.\n\nResults: LDX treatment was associated with a significant decrease in ADHD symptom interference with school activities, family interactions, homework, and social interactions (P<.01; N=11,576). Parents rated satisfaction with LDX as significantly higher than with their child’s previous treatment (P<.01). On average, global improvement, tolerability, convenience, and satisfaction with LDX were all highly rated.\n\nConclusion:

Buparlisib PI3K/Akt/mTOR inhibitor Patients treated with LDX showed significant symptom improvement and parents reported significantly greater satisfaction than with prior treatment. CNS Spectr. 2010;15(4):248-256.”
“Dietary guidelines based on 5 food groups was used as a main nutrition education tool until 1996 when food based dietary guidelines (FBDGs) were promoted after 2 years of formulation and development. These

FBDGs for the general population were designed to promote desirable and culturally acceptable eating behavior. The nine qualitative guidelines of Thai FBDGs include: 1. eat a variety of foods from each of the five food groups and maintain proper weight, 2. eat adequate rice, or alternate carbohydrate, 3. eat plenty of vegetables and fruits regularly, 4. eat fish, lean meats, eggs, legumes and pulses regularly, Selleck LY3023414 5. drink sufficient amount of milk every day, 6. take moderate amounts of fat, 7. avoid excessive intake of sweet and salty foods, 8. eat clean and uncontaminated foods, and 9. avoid or reduce consumption of alcoholic beverages. In 1998, the quantitative part of Thai FBDGs or food guide model was established as “Nutrition Flag” after rigorous test for understanding and acceptability among consumers. Promotion and dissemination of the Thai FBDGs have been carried out at national and community levels through basic health, agricultural and educational services and training activities, as well as periodic campaigning via multiple communication channels and media. Recently in 2009, the FBDGs for infant and preschool children were introduced to replace the previous infant and young child feeding guidelines. There has been no formal evaluation on the impact of promotion of the Thai FBDGs but some periodic testing of knowledge and practices have shown positive results.

001) Although operative costs were higher for TEP, total costs w

001). Although operative costs were higher for TEP, total costs were comparable for the 2 procedures, as were overall hernia recurrences at 5 years after surgery. AZD5363 price However, among experienced surgeons, significantly

lower hernia recurrence rates were seen after TEP (P<.001).\n\nConclusions: In the short term, TEP was associated with more operative complications, longer operating time, and higher operative costs; however, total costs were comparable for the 2 procedures. Chronic pain and impairment of inguinal sensibility were more frequent after Lichtenstein repair. Although overall hernia recurrence rates were comparable for both procedures, hernia recurrence rates among experienced surgeons were significantly lower after TEP. Patient satisfaction was also significantly higher after TEP. Therefore, TEP should be recommended in experienced hands.”
“PURPOSE. Human Wharton’s jelly stem cells (HWJSCs) are able to differentiate into skin and oral mucosa epithelial-like cells. In this work,

we demonstrate for the first time the capability of HWJSCs to differentiate in vitro into cornea epithelial-like cells in a three-dimensional model. METHODS. First, primary cell cultures of HWJSCs, corneal epithelial cells, and corneal keratocytes were cultured and three-dimensional orthotypic and heterotypic human cornea models were generated with fibrin-agarose scaffolds. Then, in vitro differentiation of HWJSCs and corneal epithelial cells was performed with keratinocytic inductive medium in a three-dimensional system that allowed interaction between stromal and epithelial compartments. LDK378 Selleck Blasticidin S Histological, histochemical, and immunofluorescence analyses were used to determine the differentiation status of each sample. RESULTS. Our results demonstrated that HWJSCs were able to differentiate into corneal epithelial-like cells, with results similar to the native cornea. Heterotypical corneas generated with HWJSCs showed adequate differentiation

of the epithelium and stroma, and were similar to orthotypic and native corneas in the expression of epithelial markers (CK3/12, PKG, ZO1, and CX43) and extracellular matrix components (proteoglycans, collagen, elastic and reticular fibers). Immunofluorescence analysis confirmed the presence of crystallins Cry-alpha A, Cry-alpha B, Cry-beta, and Cry-zeta with moderate or weak expression of Cry-beta gamma 3 and Cry-lambda 1 (key proteins involved in cornea transparency) in both models. CONCLUSIONS. Our findings suggest that HWJSCs can be considered an alternative cell source for cornea regeneration and may offer a solution for patients with limbus stem cell deficiency.”
“An association between chronic pain conditions and alcohol dependence has been revealed in numerous studies with episodes of alcohol abuse antedating chronic pain in some people and alcohol dependence emerging after the onset of chronic pain in others.

Amyloid structures were successfully detected by NIAD-4 at neutra

Amyloid structures were successfully detected by NIAD-4 at neutral as well as acidic pH and no significant fluorescence was detectable in the presence of a-helical fibres. Thus, NIAD-4 proved to be a valuable alternative to ThT for spectroscopic studies on amyloid structures over a broad pH range.”
“The epidermis and its appendages provide organisms with protection from the environment, keeping pathogens out and preventing the loss of essential body fluids. To perform click here both

functions, the skin has elaborated a complex differentiation process known as cornification. The renewal capacity of the skin, which is responsible for maintaining tissue homeostasis, regenerating hair and repairing the epidermis after injury, resides in the basal proliferating compartment in which epidermal stem cells are located. 17-AAG cost These cells possess the remarkable capacity to both self-perpetuate and give rise to the differentiating cells that form mature tissues. Recent findings indicate that microRNAs have an essential role in orchestrating the formation of epidermis and skin appendages, in particular, at the interface

between sternness and differentiation.”
“Background. Pathologic nipple discharge (PND) is diagnosed clinically and managed by diagnostic duct excision (DDE). Mammary ductoscopy in the office setting may change this standard. We performed a prospective study to assess the utility of office ductoscopy for surgical selection in women with nipple discharge.\n\nMethods. Compound C Women with nipple discharge meeting at least 2 of 3 criteria of PND (spontaneous, single duct, bloody or serous) underwent office ductoscopy. Those showing papillomatous lesions underwent DDE in the operating room (surgical group, n = 38); if no lesion was present, women were followed clinically (observation group,

n = 21).\n\nResults. A papillomatous lesion was identified in 79% of women with 3-criteria PND and in 21% with 2 criteria (P = .001). DDE yielded a proliferative lesion in 35 of 38 women (92%). Of the 38, 27 (71%) had papillomata, 2 (5%) had florid hyperplasia, and 6 (16%) had ductal carcinoma in situ (DCIS) on final pathology. Also, 11 women with papilloma and 1 with DCIS presented with 2-criteria PND. Ductoscopy findings were a better predictor of the presence of intraductal neoplasia (area under curve [AUC] 0.9, 95% confidence interval [95% CI] 0.8-0.98) compared with 3-criteria PND (AUC 0.7, 95% CI 0.6-0.8). The 21 women in the observation group did not develop signs of malignancy or need biopsy during a 48-month follow-up period.\n\nConclusions. Our findings suggest that office ductoscopy provides accurate surgical selection of women with nipple discharge and should be considered for women with 2 criteria of PND, and those with negative ductoscopy can be safely observed. These findings need confirmation in a larger study with longer follow-up.

The results showed

that pseudowords elicited significantl

The results showed

that pseudowords elicited significantly larger N400 responses than words did, over the central-parietal recording sites, regardless of the stimulus-degradation levels. Moreover, the N400 latency was proportional to the stimulus-degradation level. The N400 effects thus remained observable even when the character pairs were highly degraded and consciously unidentifiable, in addition to the N400 effects that were observed for lightly blurred and intact character pairs. These findings supported the view that the N400 component indexes an automatic processing, providing evidence against the postlexical account.”
“The secretory clusterin (sClu) protein is highly expressed in many types of cancer, including human hepatocellular carcinoma (HCC), and is involved in tumor progression. The current study has investigated whether GW4869 sClu silencing affects tumor

cell behavior in HCC cells. HCCLM3 cells were transfected with an antisense oligonucleotide (ASO) against clusterin (OGX-011). Apoptosis was determined by TUNEL staining and flow cytometric (FCM) assay. Cell survival was assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The matrigel invasion assay was used for invasion assays. Xenografting was used to demonstrate HCCLM3 growth and metastasis. OGX-011 specifically attenuated Bromosporine the expression of sClu. Inhibition of sClu strongly induced significant reduction in cellular growth and higher rates of spontaneous endogenous apoptosis. Invasion assays indicated that OGX-011 significantly inhibits HCCLM3 cell migration and invasion in vitro.

HCCLM3 xenografts treated with OGX-011 showed growth delay beyond 14 days. Moreover, OGX-011 treatment led to a significant decrease in lung metastasis by HCCLM3 cells. Thus, OGX-011, in potentially selleck inhibitor silence CLU gene expression, may prove to be of value during HCC therapy.”
“There is an ongoing need for a red cell substitute, an oxygen-carrying solution to use primarily as a bridge until red cells are available. The replacement of oxygen-carrying capacity has driven the field of research, primarily with the development of hemoglobin-based oxygen carriers, but they are less than ideal. The formulation of a complete substitute for blood, if it can be realized, must take into account all the cellular and molecular components of the immune and coagulation systems.”
“The etching rate behavior of silicon dioxide (SiO(2), fused silica) using chlorine trifluoride (CIF(3)) gas is studied at substrate temperatures between 573 and 1273K at atmospheric pressure in a horizontal cold-wall reactor. The etching rate increases with CIF(3) gas concentration, and the overall reaction is recognized to be of the first order. The change of the etching rate with increasing substrate temperature is nonlinear, and the etching rate tends to approach a constant value at temperatures exceeding 1173K.

Neurons from differentiated cultures were purified with fluoresce

Neurons from differentiated cultures were purified with fluorescence-activated cell

sorting and characterized. Purified cultures contained more than 90% neurons, clustered with fetal brain messenger RNA samples by microarray criteria, and could form functional synaptic contacts. Virtually all cells exhibited BTSA1 mouse normal electrophysiological activity. Relative to controls, iPSC-derived, purified neurons from the two APP(Dp) patients and patient sAD2 exhibited significantly higher levels of the pathological markers amyloid-beta(1-40), phospho-tau(Thr 231) and active glycogen synthase kinase-3 beta (aGSK-3 beta). Neurons from APP(Dp) and sAD2 patients also accumulated large RAB5-positive early endosomes compared to controls. Treatment of purified neurons with beta-secretase inhibitors, but not gamma-secretase inhibitors, caused significant reductions in phospho-Tau(Thr 231) and aGSK-3 beta levels. These results suggest a direct relationship between APP proteolytic processing, but not amyloid-beta, in GSK-3 beta activation and tau phosphorylation in human neurons. Additionally, we observed that neurons with the genome of one sAD patient exhibited the phenotypes Sotrastaurin seen in familial Alzheimer’s disease samples. More generally, we demonstrate that iPSC technology

can be used to observe phenotypes relevant to Alzheimer’s disease, even though it can take decades for overt disease to manifest in patients.”
“Storage phosphor imaging may be of value for biodistribution studies of short-living radiotracers in small animals. Efficiency, sensitivity and resolution of imaging plates for short-living radioisotopes vary considerably but linear response to many radioisotopes was shown previously. However, these properties have not been compared directly find more for larger series of short-living radioisotopes, and only few Studies have directly compared data obtained from phosphor images of tissue slices with results from dissection biodistribution

studies. Therefore, we evaluated the properties of imaging plates for 11 short-living radioisotopes (F-18, P-32, Ga-67, Sr-89, Tc-99m, Y-90, In-111, I-123, I-125, I-131, and (TI)-T-201). We also evaluated the biodistribution of [I-123]FP-CIT in rat brain using both the phosphor technique and conventional dissection methods.\n\nThe imaging system showed a linear response for all tested radioisotopes over a wide range of radioactive concentrations and the efficiency, sensitivity and resolution varied greatly for the tested radioisotopes. Shielding experiments revealed the contribution of the various emission products of radioisotopes to these properties. However, quantitative biodistribution studies with radiotracers that are labeled with all tested radioisotopes, even I-123, are feasible.

A quantitative measurement of acid-induced Egr-1 and ERK transloc

A quantitative measurement of acid-induced Egr-1 and ERK translocation was performed using a high content analysis approach. Egr-1 functionality was assessed by transient transfection with Egr-1 antisense NSC 19893 oligonucleotide. Exposure

of AGS cells to acidic conditions induced Egr-1 protein expression in a pH- and time-dependent manner. Egr-1 expression was markedly increased as the pH was reduced from pH 7.4 to 6.4. High content analysis of Egr-1 activation showed acid-induced Egr-1 nuclear translocation; a maximum observed at 1-2 It followed by a decline to basal levels beyond 4 h. Acidic pH also activated ERK 1/2 phosphorylation, whereas ERK 1/2 inhibitors PD98059 and U0216 blocked both acid-induced Egr-1 and ERK translocation

and expression. Moreover, acid exposure up-regulated VEGF expression, which was inhibited by the Egr-1 antisense oligonucleotide. Our results also demonstrate that exposure to acid induces Egr-1 via MEK-ERK 1/2 pathway. Nirogacestat order These data suggest that Egr-1 activation might play a crucial role in gastric mucosal inflammation and associated epithelial injury. J. Cell. Biochem. 108: 249-260, 2009. (C) 2009 Wiley-Liss, Inc.”
“Extramural vascular invasion (EVI) in colorectal cancer is reported to be a stage-independent adverse prognostic factor, and is a core item in the Royal College of Pathologists minimum data set for colorectal cancer histopathology reporting. The detection of EVI is also highly variable amongst pathologists. Our aims were to analyse both the frequency of EVI in colorectal cancer resections, and the effect of EVI on survival, in patients operated on over a 5-year period.\n\nA retrospective analysis of patients having potentially curative surgery for colorectal cancer between January 1999 and December 2004.\n\nOver 5 selleck years, 378 patients underwent a potentially curative resection. One-hundred seven (28.3%) cancers exhibited EVI, of which

104 (97%) were T3 and T4 tumours. Survival curves with and without EVI, unadjusted for nodal status and T stage, were significantly different (P = 0.0001) with 5-year survivals of 52% and 73% respectively. Survival curves for T3 and T4 tumours stratified with and without EVI also showed significantly different survival distributions (P = 0.007). A significant difference in frequency of EVI year on year was seen (P < 0.001), ranging from 8.5% to 46.7%, whereas the number of T3 and T4 tumours in each year was not significantly different (P = 0.677).\n\nEVI is an adverse prognostic indicator for survival in patients undergoing potentially curative resection of colorectal cancer, and the routine requirement of EVI in colorectal cancer histopathology reporting is justified. Optimal specimen preparation, meticulous histopathological analysis and regular auditing of EVI detection rates are essential for the accurate staging of colorectal cancer.

004 and P<0 005, respectively) In addition, after transplanta

004 and P<0.005, respectively). In addition, after transplantation CD3(+)CD8(+)KIR2D(+) T-cells repertoires significantly increased in C1/C1 and C1/C2, but not in C2/C2 patients.\n\nConclusions. This study confirms the benefit of HLA-C allele matching on early liver transplant outcome and shows that donor HLA-C heterozygosis influences the alloresponse of C1 and C2 homozygous patients and the recuperation of CD3(+)CD8(+)KIR2D(+) T cells, suggesting an involvement in liver graft tolerance.”
“Langerhans cell histiocytosis (LCH) is sometimes resistant to conventional chemotherapies,

and treatment with 2-chlorodeoxyadenosine (2-CdA) is gaining importance as a salvage treatment for refractory or recurrent LCH. Secondary selleck compound malignancies such as acute myelogenous leukemia and myelodysplastic syndrome (MDS) due to 2-CdA have recently been reported. However, there have been no reports Selleck Tozasertib to date of cases of 2-CdA-related secondary MDS in which spontaneous remission was achieved. Here, we report the case of a 1-year-old boy with an occipital tumor who was diagnosed with LCH by biopsy and underwent chemotherapy. However, the disease relapsed and became refractory to chemotherapy. He received 2-CdA treatment, which was effective. However 6 months after the start of treatment, he developed MDS with chromosomal abnormality of 7q-. After 1-year observation without any intervention, his

hematological findings had returned to normal, and the chromosomal abnormality had also disappeared. To our knowledge, this is the first report of 2-CdA-related MDS with spontaneous hematological remission.”
“Nowadays endoscopic diverticulotomy is the surgical approach of the first choice in treatment of Zenker’s diverticulum. We report our experience with this procedure and try to sum up recent recommendations for management of surgery and postoperative care. Data of 34 patients with Zenker’s diverticulum, treated by endoscopic AZD8055 PI3K/Akt/mTOR inhibitor carbon dioxide laser diverticulotomy

at the Department of Otorhinolaryngology and Head and Neck Surgery, 1st Faculty of Medicine, Charles University, University Hospital Motol, Prague, Czech Republic, were prospectively stored and followed in relatively short period from May 2009 to December 2013. The average length of diverticulum was 32 mm. The average duration of surgery was 32 min. The patients were fed via feeding tube for 6.1 days and antibiotics were administered for 7 days. Mean hospitalization time was 7.4 days. We observed one transient recurrent laryngeal nerve paralysis and no other serious complications. Recurrence rate was 3%. We recommend complete transection of the diverticular septum in one procedure, systemic antibiotic treatment and exclusion of transoral intake for minimally 5 days, and contrast oesophagogram before resumption of oral intake to exclude fistula.

Time of surgery was significantly lower in the conventional

Time of surgery was significantly lower in the conventional AZD6244 chemical structure treatment

group. Overall a residual tumor was found after surgery in 35% of the iMRI group, and 41% of the conventional surgery group harbored a residual tumor. Total resection was achieved as intended significantly more often in the iMRI group (91%) than in the conventional group (73%) (p smaller than 0.034). Patients with a planned subtotal resection showed higher mean volumes of residual tumor in the conventional group. There was a significantly lower incidence of intrasellar tumor remnants in the iMRI group than in the conventional group. Progression-free survival after 30 months was higher according to Kaplan-Meier analysis with the use of iMRI, but a statistically significant difference could not be shown. Conclusions. The use of high-field iMRI leads to a significantly higher rate

of complete resection. In parasellar tumors a lower residual volume and a significantly lower rate of intrasellar tumor remnants were shown with the technique. So far, long-term follow-up LDN-193189 is limited for iMRI. However, after 2 years Kaplan-Meier analyses show a distinctly higher progression-free survival in the iMRI group. No significant benefit of iMRI was found for biochemical remission rates and improvement of vision. Even though the surgical time was longer with the adjunct use of iMRI, it did not increase the complication rate significantly. The authors therefore recommend routine use of high-field iMRI for pituitary surgery, if this technique is available at the particular center.”
“Background: While LINE1 (L1) retroelements comprise nearly 20% of the human genome, the majority are thought to have been rendered transcriptionally inactive, due

to either mutation or epigenetic suppression. How many L1 elements ‘escape’ these forms of repression and contribute to the transcriptome of human somatic cells? We have cloned out expressed sequence tags corresponding to the 5′ and 3′ flanks of L1 elements in order to characterize the population of elements that are being selleck actively transcribed. We also examined expression of a select number of elements in different individuals.\n\nResults: We isolated expressed sequence tags from human lymphoblastoid cell lines corresponding to 692 distinct L1 element sites, including 410 full-length elements. Four of the expression tagged sites corresponding to full-length elements from the human specific L1Hs subfamily were examined in European-American individuals and found to be differentially expressed in different family members.\n\nConclusions: A large number of different L1 element sites are expressed in human somatic tissues, and this expression varies among different individuals. Paradoxically, few elements were tagged at high frequency, indicating that the majority of expressed L1s are transcribed at low levels.