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1.
J Gastroenterol Hepatol ; 37(12): 2206, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35535652
2.
Phys Rev Lett ; 124(13): 131301, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32302154

RESUMEN

Using only cosmic microwave background polarization data from the polarbear experiment, we measure B-mode polarization delensing on subdegree scales at more than 5σ significance. We achieve a 14% B-mode power variance reduction, the highest to date for internal delensing, and improve this result to 22% by applying for the first time an iterative maximum a posteriori delensing method. Our analysis demonstrates the capability of internal delensing as a means of improving constraints on inflationary models, paving the way for the optimal analysis of next-generation primordial B-mode experiments.

3.
Phys Rev Lett ; 121(22): 221301, 2018 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-30547645

RESUMEN

We present results from an analysis of all data taken by the bicep2/Keck CMB polarization experiments up to and including the 2015 observing season. This includes the first Keck Array observations at 220 GHz and additional observations at 95 and 150 GHz. The Q and U maps reach depths of 5.2, 2.9, and 26 µK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈400 square degrees. The 220 GHz maps achieve a signal to noise on polarized dust emission approximately equal to that of Planck at 353 GHz. We take auto and cross spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz. We evaluate the joint likelihood of the spectra versus a multicomponent model of lensed-ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and we impose priors on some of these using external information from Planck and WMAP derived from larger regions of sky. The model is shown to be an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.07 at 95% confidence, which tightens to r_{0.05}<0.06 in conjunction with Planck temperature measurements and other data. The lensing signal is detected at 8.8σ significance. Running a maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.020. These are the strongest constraints to date on primordial gravitational waves.

4.
Br Poult Sci ; 58(5): 506-511, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28692350

RESUMEN

1. The E3 ubiquitin protein ligase 1 (WWP1) gene, the mutation of which causes muscular dystrophy in chickens, is expressed not only in the pectoral muscle, but also in a number of tissues such as the kidney. Therefore, this study examined some parameters related to kidney function in muscular dystrophic (MD) chickens. 2. Plasma osmolality, Na+ and K+ concentrations, aldosterone levels, and the expression of aquaporin (AQP) 2, AQP3, and α subunits of the amiloride-sensitive epithelial sodium channel (αENaC) were analysed in the kidneys of 5-week-old MD chickens and White Leghorn (WL) chickens under physiological conditions or after one day of water deprivation. 3. Plasma osmolality, Na+ concentrations, and plasma aldosterone levels were significantly higher in MD chickens than in WL chickens. αENaC mRNA expression levels were lower in MD chickens than in WL chickens. AQP2 and AQP3 mRNA expression levels were similar in the two strains of chickens. 4. Plasma osmolality correlated with aldosterone levels and AQP2 and αENaC mRNA levels in WL chickens. In MD chickens, plasma osmolality correlated with AQP2 mRNA levels, but not with plasma aldosterone or αENaC mRNA levels. 5. These results suggest that neither water reabsorption nor the expression of AQP2 and AQP3 is impaired in MD chickens and that a WWP1 gene mutation may or may not directly induce an abnormality in Na+-reabsorption in the kidneys of MD chickens, potentially through αENaC.


Asunto(s)
Pollos , Expresión Génica , Hipernatremia/veterinaria , Distrofia Muscular Animal/fisiopatología , Concentración Osmolar , Enfermedades de las Aves de Corral/fisiopatología , Animales , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Electrólitos/sangre , Hipernatremia/genética , Hipernatremia/metabolismo , Hipernatremia/fisiopatología , Riñón/metabolismo , Masculino , Distrofia Muscular Animal/genética , Distrofia Muscular Animal/metabolismo , Potasio/sangre , Enfermedades de las Aves de Corral/genética , Enfermedades de las Aves de Corral/metabolismo , Sodio/sangre
6.
Eur J Surg Oncol ; 41(6): 795-800, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25887287

RESUMEN

BACKGROUND: The aim of the present study was to evaluate the clinical significance of protein-bound polysaccharide K (PSK) in patients with primary gastric cancer who were being treated with an oral fluoropyrimidine (S-1). METHODS: Clinical reports of 190 gastric cancer patients treated with S-1 chemotherapy, with or without PSK, at Kochi Medical School between 2007 and 2012 were investigated retrospectively to analyze survival. The neutrophil:lymphocyte ratio (NLR) was also evaluated as indicator of the immunoenhancing effect of PSK. RESULTS: Overall survival was significantly longer in patients treated with S-1 + PSK than in those given S-1 alone (hazard ratio for death, 0.608; 95% confidence interval 0.375-0.985; P = 0.041). Furthermore, there was a tendency for changes in the NLR during chemotherapy to be lower in the S-1 + PSK group than in the S-1 group, but the difference did not reach statistical significance (P = 0.054). When patients were divided into groups based on preoperative NLR (i.e. <2.5 and ≥2.5), the mean (±SEM) NLR 1 month after the beginning of chemotherapy in the NLR ≥2.5 subgroup was significantly lower in patients treated with S-1 + PSK rather than S-1 alone (1.7 ± 0.7 vs. 3.3 ± 4.1, respectively; P = 0.043). CONCLUSIONS: Immunochemotherapy using PSK improves the survival of patients with advanced gastric cancer. The NLR may be a useful biomarker for evaluating prognosis in these patients.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfocitos , Neutrófilos , Neoplasias Gástricas/tratamiento farmacológico , Adenocarcinoma/sangre , Adenocarcinoma/cirugía , Anciano , Anciano de 80 o más Años , Combinación de Medicamentos , Femenino , Proteínas Fúngicas/administración & dosificación , Proteínas Fúngicas/inmunología , Humanos , Inmunoterapia , Estimación de Kaplan-Meier , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Ácido Oxónico/administración & dosificación , Polisacáridos/administración & dosificación , Polisacáridos/inmunología , Estudios Retrospectivos , Neoplasias Gástricas/sangre , Neoplasias Gástricas/cirugía , Tasa de Supervivencia , Tegafur/administración & dosificación
10.
Anim Genet ; 41(5): 554-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20331596

RESUMEN

We sequenced the 16S rRNA gene in mitochondrial DNA to characterize mithun located in Bhutan and to increase our understanding of its origin. We compared mithun with yak, European cattle, Bhutanese zebu and Indian zebu. Sequencing revealed low nucleotide diversity within the mithun population and their phylogenetic proximity to gaur. A close relationship between Bhutanese mithun and gaur was confirmed by an additional comparison with wild gaur specimens from three locations in Bhutan. Direct domestication of mithun from gaur was supported, while maternal contribution from the cattle lineage during domestication was not supported.


Asunto(s)
Bovinos/clasificación , Bovinos/genética , ADN Mitocondrial/genética , Variación Genética , Animales , Bután , Datos de Secuencia Molecular , Filogenia
11.
Anim Genet ; 39(1): 71-8, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18254737

RESUMEN

A wide diversity of domesticated chicken breeds exist due to artificial selection on the basis of human interests. Miniature variants (bantams) are eminently illustrative of the large changes from ancestral junglefowls. In this report, the genetic characterization of seven Japanese miniature chicken breeds and varieties, together with institute-kept Red Junglefowl, was conducted by means of typing 40 microsatellites located on 21 autosomes. We drew focus to genetic differentiation between the miniature chicken breeds and Red Junglefowl in particular. A total of 305 alleles were identified: 27 of these alleles (8.9%) were unique to the Red Junglefowl with high frequencies (>20%). Significantly high genetic differences (F(ST)) were obtained between Red Junglefowl and all other breeds with a range of 0.3901-0.5128. Individual clustering (constructed from combinations of the proportion of shared alleles and the neighbour-joining method) indicated high genetic divergence among breeds including Red Junglefowl. There were also individual assignments on the basis of the Bayesian and distance-based approaches. The microsatellite differences in the miniature chicken breeds compared to the presumed wild ancestor reflected the phenotypic diversity among them, indicating that each of these miniature chicken breeds is a unique gene pool.


Asunto(s)
Pollos/genética , Variación Genética , Repeticiones de Microsatélite , Alelos , Animales , Cruzamiento , Pollos/anatomía & histología , Pollos/clasificación , Femenino , Japón , Masculino , Fenotipo , Filogenia , Especificidad de la Especie
12.
Cytogenet Genome Res ; 117(1-4): 240-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17675865

RESUMEN

This paper reviews studies on sex reversal experiments in chickens, production of sperm bearing a female-specific chromosome, its application for poultry resources and finally a mechanism of sex differentiation of gonads in the chicken.


Asunto(s)
Pollos/genética , Cromosomas/genética , Espermatozoides/metabolismo , Animales , Trastornos del Desarrollo Sexual , Femenino , Masculino , Procesos de Determinación del Sexo , Diferenciación Sexual , Espermatozoides/citología
13.
Surg Endosc ; 20(10): 1621-5, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16897287

RESUMEN

BACKGROUND: Recent advances in laparoscopic surgery have made various abdominal surgeries possible. To avoid wound infection, mesh repair of abdominal incisional hernias is performed laparoscopically. Here we present a new procedure to fix mesh to the abdominal wall. SURGICAL TECHNIQUE: Four anchoring sutures are made using a suture-grasping device; the additional transabdominal sutures are then made with a modified double-needle device. Additional circumferential fixation with tacks is not necessary. CONCLUSIONS: This new mesh fixation method involves simple suturing techniques and is less time consuming than the conventional procedure.


Asunto(s)
Hernia Abdominal/cirugía , Laparoscopía , Mallas Quirúrgicas , Técnicas de Sutura , Pared Abdominal/cirugía , Hernia Abdominal/etiología , Humanos , Técnicas de Sutura/instrumentación
14.
Surg Endosc ; 20(4): 563-9, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16391959

RESUMEN

BACKGROUND: When we perform laparoscopic lymph node dissection around the inferior mesenteric artery (IMA), we preserve the left colic artery (LCA) to maintain the blood supply to the proximal sigmoid colon. In this study, we present our laparoscopic D2 and D3 lymph node (LN) dissection technique and evaluate its applicability and safety. METHODS: We performed LN dissection on 23 rectal and lower sigmoid colon cancer cases from April 2002 to December 2004. For D3 LN dissection, the incision to the mesosigmoid extends to just before the root of the IMA, which is exposed with an ultrasonic cutting and coagulating surgical device to avoid bleeding. Then, the arterial wall is exposed with a dissecting electrocautery spatula down to the LCA, at least 2 cm of which is exposed. Adipose tissue surrounding the IMA and inferior mesenteric vein is dissected. For D2 LN dissection, we partially expose the IMA to confirm the location of the LCA. RESULTS: The mean times taken for D2 and D3 LN dissections were 36.2 and 68.2 min, respectively. Both procedures took longer in male patients. There was a trend for the procedure overall to take less time in female patients. However, D2 dissection took significantly longer in male than female patients (p < 0.05). In women, D3 dissection took significantly longer than D2 (p < 0.05), but this trend was not seen in men. Increased experience among surgeons with this procedure was associated with significantly faster LN dissections in men (p < 0.05), but not in women (p = 0.493). Pearson product moment analysis identified a relationship between body mass index (BMI) and the time taken for D2 LN dissection (r = 0.765), but not D3 LN dissection (r = 0.158). There was no treatment-related morbidity with this technique. CONCLUSIONS: This method was safe and feasible for all patients in this series, but takes longer to perform in male patients.


Asunto(s)
Neoplasias del Colon/cirugía , Laparoscopía , Escisión del Ganglio Linfático/métodos , Ganglios Linfáticos/cirugía , Arteria Mesentérica Inferior , Neoplasias del Recto/cirugía , Anciano , Arterias/fisiopatología , Colon Sigmoide/irrigación sanguínea , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
15.
Anim Genet ; 34(2): 96-101, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12648092

RESUMEN

Using nucleotide sequences of the mitochondrial DNA (mtDNA) cytochrome b and SRY genes, we examined the genetic status of two major groups of domestic cattle, the humpless taurine (Bos taurus) and humped zebu (B. indicus), using 10 cattle populations in Asia. Several sequence polymorphisms specific for each major group were found, although the frequency of these polymorphisms varied in each population. Six major mtDNA-SRY composite types were observed. The Mishima, Mongolian, Korean, Chinese Yellow and Sri Lanka cattle populations had a full match between the mtDNA and SRY sequences, specifically the taurine/taurine type or zebu/zebu type. A non-match type (zebu/taurine type) was found at a high frequency in the Bangladesh (83.4%) and Nepal populations (83.3%). Our results suggest that these non-match type populations developed from genetic hybridization of different strains. Also, the domestication history of modern Asian domestic cattle could be explained by male-mediated introgression. Additionally, our results suggest the occurrence of introgression of mtDNA from other Bibos or Poephagus species into native cattle populations. The existence of other mtDNA-SRY composite types, such as the Bali-zebu and yak-zebu types in Indonesia (85.7%) and Nepal (16.7%), respectively, suggests that genetic introgression also occurred from other genera into domestic cattle during the process of domestication.


Asunto(s)
Bovinos/genética , ADN Mitocondrial/genética , Proteínas de Unión al ADN/genética , Proteínas Nucleares , Filogenia , Factores de Transcripción , Animales , Secuencia de Bases , Cartilla de ADN , Masculino , Reacción en Cadena de la Polimerasa , Proteína de la Región Y Determinante del Sexo
16.
Biochem Genet ; 40(3-4): 101-16, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12017505

RESUMEN

Six flying fox species, genus Pteropus (four from the Philippines) were investigated using complete cytochrome b gene sequences (1140 bp) to infer their evolutionary relationships. The DNA sequences generated via polymerase chain reaction were analyzed using the neighbor-joining, parsimony, and maximum likelihood methods. We estimated that the first evolutionary event among these Pteropus species occurred approximately 13.90 +/- 1.49 MYA. Within this short period of evolutionary time we further hypothesized that the ancestors of the flying foxes found in the Philippines experienced a subsequent diversification forming two clusters in the topology. The first cluster is composed of P. pumilus (Philippine endemic), P. speciosus (restricted in western Mindanao) with P. scapulatus, while the second one comprised P. vampyrus and P. dasymallus species based on the analysis from first and second codon positions. Consistently, all phylogenetic analyses divulged close association of P. dasymallus with P. vampyrus contradicting the previous report categorizing P. dasymallus under subniger species group with P. pumilus. P. speciosus, and P. hypomelanus. The Philippine endemic species (P. pumilus) is closely linked with P. speciosus. The representative samples of P. vampyrus showed a large genetic distance of 1.87%. The large genetic distance between P. dasymallus and P. hypomelanus, P. pumilus and P. speciosus denotes a distinct species group.


Asunto(s)
Quirópteros/genética , Grupo Citocromo b/genética , ADN Mitocondrial , Evolución Molecular , Animales , Quirópteros/clasificación , Filipinas , Filogenia
17.
Cytogenet Genome Res ; 99(1-4): 310-4, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12900580

RESUMEN

In birds, females are heterogametic (ZW), while males are homogametic (ZZ). It has been proposed that there is no dosage compensation for the expression of Z-linked genes in birds. In order to examine if the genes are inactivated on one of the two Z chromosomes, we analyzed the allelic expression of the B4GALT1 and CHD-Z genes on Z chromosomes in male chickens. One base substitution was detected among 15 chicken breeds and lines examined for each gene, and cross mating was made between the breeds or lines with polymorphism. cDNAs were synthesized from cultured cell colonies each derived from a single cell of an F1 male embryo. The allelic expression of the B4GALT1 gene was examined by restriction fragment length polymorphism analysis of the PCR products digested with RSAI, and that of the CHD-Z gene by the single nucleotide primer extension (SNuPE) method. Both of the genes displayed biallelic expression, suggesting that these Z-linked genes were not subject to inactivation in male chickens. Comparison between expression levels in males and females by real-time quantitative PCR suggested that expression was compensated for the CHD-Z gene but not for the B4GALT1 gene.


Asunto(s)
Proteínas Aviares , Pollos/genética , Cromosomas Sexuales/genética , Alelos , Animales , Secuencia de Bases , Células Cultivadas , Embrión de Pollo , ADN/química , ADN/genética , Análisis Mutacional de ADN , Proteínas de Unión al ADN/genética , Femenino , Regulación del Desarrollo de la Expresión Génica , Ligamiento Genético , Masculino , N-Acetil-Lactosamina Sintasa/genética , Polimorfismo de Nucleótido Simple , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
18.
Cytogenet Cell Genet ; 93(3-4): 258-62, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11528122

RESUMEN

Forty-one cDNA clones of human functional genes were newly mapped to chromosomes of the musk shrew (Suncus murinus, Insectivora) by fluorescence in situ hybridization, and a comparative cytogenetic map of 51 genes, including 10 genes reported in our previous study, was constructed between human (HSA) and musk shrew (SMU) chromosomes. In this comparative map, the 51 genes localized to human autosomes, except HSA 8, 16, and 20, were mapped to 15 shrew autosomes, except SMU 4, 16, 17 and 18. Twelve conserved segments were identified between human and shrew chromosomes, and six segments among the musk shrew, human, and mouse. Our results defined the presence of at least one inversion and several interchromosomal rearrangements that occurred during evolution after the two species diverged from a common ancestor. Localization of three major histocompatibility complex (MHC) genes to shrew chromosome 3 suggested that the MHC genes of the musk shrew are located in a cluster on chromosome 3. The cytogenetic map constructed in this study is the first cytogenetic map with many functional genes in insectivore species. This approach provides clues for clarifying the chromosomal evolution in this order.


Asunto(s)
Hibridación Fluorescente in Situ , Mapeo Físico de Cromosoma , Musarañas/genética , Animales , Proteínas Portadoras/genética , Bandeo Cromosómico , Clonación Molecular , Secuencia Conservada/genética , ADN Complementario/genética , Genes , Humanos , Ratones , Proteína Tirosina Fosfatasa no Receptora Tipo 13 , Proteínas Tirosina Fosfatasas/genética
19.
Exp Anim ; 50(4): 319-24, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11515095

RESUMEN

We performed a genome-wide quantitative trait locus (QTL) analysis of body weight at 10 weeks of age in a population of 321 intercross offspring from SM/J and A/J mice, progenitor strains of SMXA recombinant inbred strains. Interval mapping revealed two significant QTLs, Bwq3 (body weight QTL3) and Bwq4, on Chromosomes (Chrs) 8 and 18 respectively, and five suggestive QTLs on Chrs 2, 6, 7, 15 and 19. Bwq3 and Bwq4 explained 6% of the phenotypic variance. The SM/J alleles at both QTLs increased body weight, though the SM/J mouse was smaller than the A/J mouse. On the other hand, four of the five suggestive QTLs detected had male-specific effects on body weight and the remainder was female-specific. These suggestive QTLs explained 5-6% of the phenotypic variance and all the SM/J alleles decreased body weight.


Asunto(s)
Peso Corporal/genética , Mapeo Cromosómico , Variación Genética , Alelos , Animales , Femenino , Marcadores Genéticos , Masculino , Ratones , Ratones Endogámicos , Linaje , Fenotipo , Carácter Cuantitativo Heredable
20.
J Hered ; 92(3): 282-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11447248

RESUMEN

The direct R-banding fluorescence in situ hybridization (FISH) method was used to map 18S-28S ribosomal RNA genes and 10 human cDNA clones on the chromosomes of the musk shrew (Suncus murinus). The chromosomal locations of 18S-28S ribosomal RNA genes were examined in the five laboratory lines and wild animals captured in the Philippines and Vietnam, and the genes were found on chromosomes 5, 6, 9, and 13 with geographic variation. The comparative mapping of 10 cDNA clones of human chromosome 1 demonstrated that human chromosome 1 consisted of at least three segments homologous to Suncus chromosomes (chromosomes 7, 10, and 14). This approach with the direct R-banding FISH method is useful for constructing comparative maps between human and insectivore species and for explicating the process of chromosomal rearrangements during the evolution of mammals.


Asunto(s)
Mapeo Cromosómico , Cromosomas Humanos Par 1/genética , Hibridación Fluorescente in Situ/métodos , ARN Ribosómico 18S/genética , ARN Ribosómico 28S/genética , Musarañas/genética , Animales , Encéfalo , Bandeo Cromosómico , Cromosomas Humanos Par 10/genética , Cromosomas Humanos Par 14/genética , Cromosomas Humanos Par 7/genética , Sondas de ADN , ADN Complementario/genética , Heterocigoto , Humanos
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