Neocentrics and holokinetics (holocentrics): chromosomes out of the centromeric rules

The centromere appears as a single constriction at mitotic metaphase in most eukaryotic chromosomes. Holokinetic chromosomes are the exception to this rule because they do not show any centromeric constrictions. Holokinetic chromosomes are usually forgotten in most reviews about centromeres, despite their presence in a number of animal and plant species. They are generally linked to very intriguing and unusual mechanisms of mitosis and meiosis. Holokinetic chromosomes differ from monocentric chromosomes not only in the extension of the kinetochore plate, but also in many other peculiar karyological features, which could be understood as the 'holokinetic syndrome' that is reviewed in detail. Together with holokinetic chromosomes we review neocentromeric activity, a similarly intriguing case of regions able to pull chromosomes towards the poles without showing the main components reported to be essential to centromeric function. A neocentromere is a chromosomal region different from the true centromere in structure, DNA sequence and location, but is able to lead chromosomes to the cell poles in special circumstances. Neocentromeres have been reported in plants and animals showing different features. Both in humans and Drosophila, neocentric activity appears in somatic cells with defective chromosomes lacking a functional centromere. In most cases in plants, neocentromeres appear in chromosomes which have normal centromeres, but are active only during meiosis. Because of examples such as spontaneous or induced neocentromeres and holokinetic chromosomes, it is becoming less surprising that different structures and DNA sequences of centromeres appear in evolution.

A universal support vector machines based method for automatic event location in waveforms and video-movies: applications to massive nuclear fusion databases

Big physics experiments can collect terabytes (even petabytes) of data under continuous or long pulse basis. The measurement systems that follow the temporal evolution of physical quantities translate their observations into very large time-series data and video-movies. This article describes a universal and automatic technique to recognize and locate inside waveforms and video-films both signal segments with data of potential interest for specific investigations and singular events. The method is based on regression estimations of the signals using support vector machines. A reduced number of the samples is shown as outliers in the regression process and these samples allow the identification of both special signatures and singular points. Results are given with the database of the JET fusion device: location of sawteeth in soft x-ray signals to automate the plasma incremental diffusivity computation, identification of plasma disruptive behaviors with its automatic time instant determination, and, finally, recognition of potential interesting plasma events from infrared video-movies.

Outbreak of 2009 pandemic influenza A(H1N1), Los Lagos, Chile, April-June 2009

On 17 May 2009, the first two cases of 2009 pandemic influenza A(H1N1) were confirmed in the Metropolitan region (Santiago, Chile). On 6 June 2009, Chile reported 500 confirmed cases, seven severe and two fatal. Because six of the severe cases and the two deaths occurred in the region of Los Lagos in southern Chile, a retrospective study was conducted using data on emergency room visits as well as laboratory viral surveillance, during the period from 1 April to 31 May, in order to establish the date of the beginning of the outbreak. From 1 to 27 June, data were collected in real time, to establish the real magnitude of the outbreak, describe its transmission, clinical severity and secondary attack rates. Confirmed cases, their household contacts and healthcare workers were interviewed. This analysis showed that the outbreak in Los Lagos started on 28 April. By 27 June, a total of 14.559 clinical cases were identified, affecting mostly 5-19 year-olds. The effective reproduction number during the initial phase (20 days) was 1.8 (1.6-2.0). Of the 190 confirmed cases with severe acute respiratory infection, 71 (37.4%) presented a risk condition or underlying illness.

Transanal rectocele repair using linear stapler and bioabsorbable staple line reinforcement material: short-term results of a prospective study

PURPOSE

This study was designed to determine the short-term results of transanal rectocele repair with use of a linear stapler and Bioabsorbable Seamguard.

METHODS

Ten women (median age, 56.1 y) with obstructed defecation syndrome were enrolled in the study. The preoperative study consisted of a medical history, physical examination, anoscopy, endoanal ultrasound, and defecography. All patients completed a severity score and a visual analog scale for global quality of life, and provided the postoperative dates of complications.

RESULTS

Overall, the treatment significantly improved the obstructed defecation: the severity score improved from a median of 19.8 +/- 4.2 at baseline to 6.10 +/- 8.2 at one month (P < .005), 5.9 +/- 8.3 at 6 months (P < .005), and 6 +/- 8.3 at one year after the operation (P < .005). A significant improvement was observed in the visual analog scale, which improved from a median of 1.8 +/- 1.4 at baseline to 6 +/- 1.6 at one month (P < .005), 6.6 +/- 2.1 at 6 months (P < .004), and 7 +/- 2.5 at one year (P < .004). A significant improvement was also observed in various symptoms. Only 2 patients manifested urgent defecation.

CONCLUSIONS

The present study demonstrates that rectocele repair using a linear stapler and Seamguard is a safe, easy procedure, with a very low rate of complications and good immediate outcome.

A narrow and highly significant linkage signal for severe bipolar disorder in the chromosome 5q33 region in Latin American pedigrees

We previously reported linkage of bipolar disorder to 5q33-q34 in families from two closely related population isolates, the Central Valley of Costa Rica (CVCR) and Antioquia, Colombia (CO). Here we present follow up results from fine-scale mapping in large CVCR and CO families segregating severe bipolar disorder, BP-I, and in 343 population trios/duos from CVCR and CO. Employing densely spaced SNPs to fine map the prior linkage peak region increases linkage evidence and clarifies the position of the putative BP-I locus. We performed two-point linkage analysis with 1134 SNPs in an approximately 9 Mb region between markers D5S410 and D5S422. Combining pedigrees from CVCR and CO yields a LOD score of 4.9 at SNP rs10035961. Two other SNPs (rs7721142 and rs1422795) within the same 94 kb region also displayed LOD scores greater than 4. This linkage peak coincides with our prior microsatellite results and suggests a narrowed BP-I susceptibility regions in these families. To investigate if the locus implicated in the familial form of BP-I also contributes to disease risk in the population, we followed up the family results with association analysis in duo and trio samples, obtaining signals within 2 Mb of the peak linkage signal in the pedigrees; rs12523547 and rs267015 (P = 0.00004 and 0.00016, respectively) in the CO sample and rs244960 in the CVCR sample and the combined sample, with P = 0.00032 and 0.00016, respectively. It remains unclear whether these association results reflect the same locus contributing to BP susceptibility within the extended pedigrees.

Evaluation of the use of posterior tibial nerve stimulation for the treatment of fecal incontinence: preliminary results of a prospective study

PURPOSE

Neuromodulation therapies have been used with success in patients with fecal incontinence. Intermittent percutaneous tibial nerve stimulation is a new, minimally invasive treatment option for these patients. This study was designed to evaluate the results of intermittent percutaneous tibial nerve stimulation in patients with fecal incontinence.

METHODS

Sixteen patients (11 females; mean age, 59 +/- 7.9 years) with severe fecal incontinence were treated with percutaneous tibial nerve stimulation. All patients completed a defecation diary, the Wexner Fecal Continence Scale, a fecal incontinence quality-of-life questionnaire, and a visual analog scale before treatment and during each phase of the study. Endoluminal ultrasound and anorectal physiologic studies were also performed in each patient.

RESULTS

Continence was improved in 10 of 16 patients after the first phase. Six patients did not continue to the second phase of treatment because of a lack of initial response. During the second phase, 7 of 16 continued to show improvement. After a six-month period without any treatment, 5 of 16 continued to have good continence. Overall, percutaneous tibial nerve stimulation significantly improved fecal continence. The Wexner score improved from a mean of 13.2 +/- 4.1 at baseline to 9 +/- 5.2 at the end of the first phase (P < 0.0005), to 8 +/- 5.7 at the end of the second phase (P = 0.001), and to 9.1 +/- 5 after 6 months without treatment (P = 0.001). Significant improvement was observed in three main domains of the fecal incontinence quality-of-life scale: coping/behavior, depression, and embarrassment. Scores on the visual analog scale improved from a mean of 4.6 +/- 1.5 at baseline to 7 +/- 2.5 at the end of the first phase (P = 0.002) and to 7.2 +/- 2.5 after 6 months without treatment (P = 0.001).

CONCLUSION

Percutaneous tibial nerve stimulation is a minimally invasive and effective treatment option for patients with fecal incontinence.

Invasion and survival of Photobacterium damselae subsp. piscicida in non-phagocytic cells of gilthead sea bream, Sparus aurata L

Fluorescence microscopy and gentamicin protection assays were used to investigate the ability of four Photobacterium damselae subsp. pisicida (Phdp) strains to adhere to and to invade the fish epithelial cell line, SAF-1, derived from Sparus aurata. All strains tested were detected intracellularly using both techniques, although internalization levels varied among strains. Treatment with cytochalasin D and experiments carried out at 4 degrees C demonstrated that a functional host cell cytoskeleton and active cell metabolism are necessary for bacterial internalization. Intracellular bacteria were detected for up to 7 days with a round morphology and were stained with DAPI, indicating that some bacterial cells may remain viable inside SAF-1 cells. Our in vitro findings indicate that Phdp are capable of adhering, entering and surviving within the non-phagocytic epithelial cell line SAF-1, which may be important for persistence and establishment of a carrier state in S. aurata.

First Report of Orange Rust of Sugarcane Caused by Puccinia kuehnii in Costa Rica and Nicaragua

Symptoms and signs of orange rust on sugarcane (a complex hybrid of Saccharum L. species) were observed from July 2007 on cv. SP 71-5574 in Costa Rica at the Coopeagri Sugar Mill located in Pérez Zeledón, San José and on multiple cultivars (CP 72-2086, Pindar, Q 132, Q 138, SP 71-5574, and SP 79-2233) at the Providencia Sugar Mill near Muelle, San Carlos and Cutris Sugar Mill near Los Chiles during August 2007. The same symptoms and signs were observed on cv. CP 72-2086 during September 2007 in Nicaragua at Ingenio San Antonio, located near Chinandega, and Ingenio Monte Rosa near El Viejo, Nicaragua. Disease symptoms and uredinia appeared different from brown rust caused by Puccinia melanocephala, and brown rust usually does not occur on these cultivars. Uredinia and urediniospores were similar to those described for orange rust (1,2). Cvs. SP 71-5574 and SP 79-2233 are susceptible and cv. CP 72-2086 is moderately susceptible to orange rust in Costa Rica and cvs. ISACP 00-1075, ISA 00-1000, and CP 72-2086 are moderately susceptible in Nicaragua. Samples from both locations (Costa Rica BPI No. 878816 and Nicaragua BPI No. 878817) examined at the USDA-ARS Mycology and Microbiology Laboratory in Beltsville, MD showed morphological characteristics consistent with those of P. kuehnii. Analysis of ITS1, 5.8S, and ITS2 rDNA sequences of the rust infecting cv. CP 72-2086 (GenBank Accession No. FJ532477) from Costa Rica and cv. ISA 00-1000 from Nicaragua (GenBank Accession No. FJ532476) confirmed the identity as P. kuehnii, the causal agent of sugarcane orange rust. Beside the cultivars already mentioned, orange rust also was confirmed on cvs. RB 73-9735 and CPCL 02-2130 in Costa Rica. To our knowledge, this is the first report of orange rust of sugarcane in Costa Rica and Nicaragua and the third confirmation of the disease in the Western Hemisphere and Caribbean Basin. References: (1) J. C. Comstock et al. Plant Dis. 92:175, 2008. (2) W. Ovalle et al. Plant Dis. 92:973, 2008.

Feature extraction for improved disruption prediction analysis at JET

Disruptions are major instabilities and remain one of the main problems in tokomaks. Using Joint European Torus database, a disruption predictor is developed by computational methods including supervised learning techniques. The main objectives of the work are to develop accurate automatic classifiers, to test their performances, and to determine how much in advance of the disruption they can operate with acceptable reliability.