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Background: Sargramostim (yeast-derived, glycosylated recombinant human granulocyte-macrophage colony-stimulating factor [rhu GM-CSF]) augments innate and adaptive immune responses and accelerates hematopoietic recovery of chemotherapy-induced neutropenia. However, considerably less is known about its efficacy as adjunctive immunotherapy against invasive fungal diseases (IFDs). Methods: The clinical courses of 15 patients with pediatric malignancies and IFDs treated adjunctively with sargramostim at a single institution were analyzed in a retrospective cohort review. Further, a systematic review of published reports of rhu GM-CSF for IFDs was also conducted. Results: Among 65 cases, 15 were newly described pediatric patients and 50 were previously published cases of IFDs treated with rhu GM-CSF. Among the newly reported pediatric patients, IFDs were caused by Candida spp., Trichosporon sp., and molds (Aspergillus spp., Rhizopus sp., Lichtheimia sp., and Scedosporium sp). Twelve (80%) were neutropenic at baseline, and 12 (80%) were refractory to antifungal therapy. Among 12 evaluable patients, the overall response rate was 92% (8 [67%] complete responses, 3 [25%] partial responses, and 1 [8%] stable). Treatment is ongoing in the remaining 3 patients. Among 50 published cases (15 Candida spp., 13 Mucorales, 11 Aspergillus spp., 11 other organisms), 20 (40%) had baseline neutropenia and 36 (72%) were refractory to standard therapy before rhu GM-CSF administration. Consistent with responses in the newly reported patients, the overall response rate in the literature review was 82% (40 [80%] complete responses, 1 [2%] partial response, and 9 [18%] no response). Conclusions: Sargramostim may be a potential adjunctive immunomodulator for selected patients with hematological malignancies and refractory IFDs.
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BACKGROUND: Colonoscopy surveillance is recommended for some patients post polypectomy. The 2002 UK surveillance guidelines classify post-polypectomy patients into low, intermediate and high risk, and recommend different strategies for each classification. Limited evidence supports these guidelines. OBJECTIVES: To examine, for each risk group, long-term colorectal cancer incidence by baseline characteristics and the number of surveillance visits; the effects of interval length on detection rates of advanced adenomas and colorectal cancer at first surveillance; and the cost-effectiveness of surveillance compared with no surveillance. DESIGN: A retrospective cohort study and economic evaluation. SETTING: Seventeen NHS hospitals. PARTICIPANTS: Patients with a colonoscopy and at least one adenoma at baseline. MAIN OUTCOME MEASURES: Long-term colorectal cancer incidence after baseline and detection rates of advanced adenomas and colorectal cancer at first surveillance. DATA SOURCES: Hospital databases, NHS Digital, the Office for National Statistics, National Services Scotland and Public Health England. METHODS: Cox regression was used to compare colorectal cancer incidence in the presence and absence of surveillance and to identify colorectal cancer risk factors. Risk factors were used to stratify risk groups into higher- and lower-risk subgroups. We examined detection rates of advanced adenomas and colorectal cancer at first surveillance by interval length. Cost-effectiveness of surveillance compared with no surveillance was evaluated in terms of incremental costs per colorectal cancer prevented and per quality-adjusted life-year gained. RESULTS: Our study included 28,972 patients, of whom 14,401 (50%), 11,852 (41%) and 2719 (9%) were classed as low, intermediate and high risk, respectively. The median follow-up time was 9.3 years. Colorectal cancer incidence was 140, 221 and 366 per 100,000 person-years among low-, intermediate- and high-risk patients, respectively. Attendance at one surveillance visit was associated with reduced colorectal cancer incidence among low-, intermediate- and high-risk patients [hazard ratios were 0.56 (95% confidence interval 0.39 to 0.80), 0.59 (95% confidence interval 0.43 to 0.81) and 0.49 (95% confidence interval 0.29 to 0.82), respectively]. Compared with the general population, colorectal cancer incidence without surveillance was similar among low-risk patients and higher among high-risk patients [standardised incidence ratios were 0.86 (95% confidence interval 0.73 to 1.02) and 1.91 (95% confidence interval 1.39 to 2.56), respectively]. For intermediate-risk patients, standardised incidence ratios differed for the lower- (0.70, 95% confidence interval 0.48 to 0.99) and higher-risk (1.46, 95% confidence interval 1.19 to 1.78) subgroups. In each risk group, incremental costs per colorectal cancer prevented and per quality-adjusted life-year gained with surveillance were lower for the higher-risk subgroup than for the lower-risk subgroup. Incremental costs per quality-adjusted life-year gained were lowest for the higher-risk subgroup of high-risk patients at £7821. LIMITATIONS: The observational design means that we cannot assume that surveillance caused the reductions in cancer incidence. The fact that some cancer staging data were missing places uncertainty on our cost-effectiveness estimates. CONCLUSIONS: Surveillance was associated with reduced colorectal cancer incidence in all risk groups. However, in low-risk patients and the lower-risk subgroup of intermediate-risk patients, colorectal cancer incidence was no higher than in the general population without surveillance, indicating that surveillance might not be necessary. Surveillance was most cost-effective for the higher-risk subgroup of high-risk patients. FUTURE WORK: Studies should examine the clinical effectiveness and cost-effectiveness of post-polypectomy surveillance without prior classification of patients into risk groups. TRIAL REGISTRATION: This trial is registered as ISRCTN15213649. FUNDING: This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 26. See the NIHR Journals Library website for further project information.
Bowel cancers develop from polyps, also called adenomas, which are growths on the lining of the bowel. Removal of adenomas, therefore, helps prevent bowel cancer. Adenomas can be detected and removed during colonoscopy, when a thin tube with a camera on one end is used to examine the bowel lining. In the UK, patients with adenomas are divided into three risk groups. Low-risk patients (i.e. those with one or two adenomas that are < 10 mm in size) are thought to be unlikely to develop bowel cancer after adenoma removal and follow-up colonoscopy is not recommended in this group. Intermediate-risk patients (i.e. those with three or four adenomas that are < 10 mm in size, or one or two adenomas with at least one ≥ 10 mm in size) are recommended to have another colonoscopy 3 years after adenoma removal. High-risk patients (i.e. those with five or more adenomas that are < 10 mm in size, or three or more adenomas with at least one ≥ 10 mm in size) are recommended to have another colonoscopy after 1 year and then usually again after 3 years. The number of follow-up colonoscopies carried out is stretching health-care resources and each procedure carries a small risk of complications for patients. It is possible that too many follow-up colonoscopies are being carried out. This study aimed to determine which patients require follow-up colonoscopies and how many are required to detect adenomas and prevent bowel cancer, while also being resource-efficient, cost-effective and not exposing patients to unnecessary risks. The study used data from 17 hospitals and cancer registries in the UK. In each risk group, one follow-up colonoscopy after adenoma removal was associated with a 4050% reduction in bowel cancer risk. However, even without any follow-up, bowel cancer risk was no higher in some low- and intermediate-risk patients than in the general population. These patients may not need as many follow-up colonoscopies as recommended. In the case of higher-risk patients, who even after adenoma removal have a higher bowel cancer risk than the general population, follow-up colonoscopies are necessary and cost-effective.
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Adenoma , Neoplasias Colorrectales , Adenoma/epidemiología , Adenoma/prevención & control , Colonoscopía , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/prevención & control , Análisis Costo-Beneficio , Humanos , Estudios RetrospectivosRESUMEN
OBJECTIVE: Colonoscopy surveillance aims to reduce colorectal cancer (CRC) incidence after polypectomy. The 2020 UK guidelines recommend surveillance at 3 years for 'high-risk' patients with ≥2 premalignant polyps (PMPs), of which ≥1 is 'advanced' (serrated polyp (or adenoma) ≥10 mm or with (high-grade) dysplasia); ≥5 PMPs; or ≥1 non-pedunculated polyp ≥20 mm; 'low-risk' patients without these findings are instead encouraged to participate in population-based CRC screening. We examined the appropriateness of these risk classification criteria and recommendations. DESIGN: Retrospective analysis of patients who underwent colonoscopy and polypectomy mostly between 2000 and 2010 at 17 UK hospitals, followed-up through 2017. We examined CRC incidence by baseline characteristics, risk group and number of surveillance visits using Cox regression, and compared incidence with that in the general population using standardised incidence ratios (SIRs). RESULTS: Among 21 318 patients, 368 CRCs occurred during follow-up (median: 10.1 years). Baseline CRC risk factors included age ≥55 years, ≥2 PMPs, adenomas with tubulovillous/villous/unknown histology or high-grade dysplasia, proximal polyps and a baseline visit spanning 2-90 days. Compared with the general population, CRC incidence without surveillance was higher among those with adenomas with high-grade dysplasia (SIR 1.74, 95% CI 1.21 to 2.42) or ≥2 PMPs, of which ≥1 was advanced (1.39, 1.09 to 1.75). For low-risk (71%) and high-risk (29%) patients, SIRs without surveillance were 0.75 (95% CI 0.63 to 0.88) and 1.30 (1.03 to 1.62), respectively; for high-risk patients after first surveillance, the SIR was 1.22 (0.91 to 1.60). CONCLUSION: These guidelines accurately classify post-polypectomy patients into those at high risk, for whom one surveillance colonoscopy appears appropriate, and those at low risk who can be managed by non-invasive screening.
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Pólipos del Colon/patología , Pólipos del Colon/cirugía , Colonoscopía , Neoplasias Colorrectales/epidemiología , Anciano , Femenino , Humanos , Masculino , Vigilancia de la Población , Estudios Retrospectivos , Factores de Riesgo , Reino Unido/epidemiologíaRESUMEN
OBJECTIVE: Postpolypectomy colonoscopy surveillance aims to prevent colorectal cancer (CRC). The 2002 UK surveillance guidelines define low-risk, intermediate-risk and high-risk groups, recommending different strategies for each. Evidence supporting the guidelines is limited. We examined CRC incidence and effects of surveillance on incidence among each risk group. DESIGN: Retrospective study of 33 011 patients who underwent colonoscopy with adenoma removal at 17 UK hospitals, mostly (87%) from 2000 to 2010. Patients were followed up through 2016. Cox regression with time-varying covariates was used to estimate effects of surveillance on CRC incidence adjusted for patient, procedural and polyp characteristics. Standardised incidence ratios (SIRs) compared incidence with that in the general population. RESULTS: After exclusions, 28 972 patients were available for analysis; 14 401 (50%) were classed as low-risk, 11 852 (41%) as intermediate-risk and 2719 (9%) as high-risk. Median follow-up was 9.3 years. In the low-risk, intermediate-risk and high-risk groups, CRC incidence per 100 000 person-years was 140 (95% CI 122 to 162), 221 (195 to 251) and 366 (295 to 453), respectively. CRC incidence was 40%-50% lower with a single surveillance visit than with none: hazard ratios (HRs) were 0.56 (95% CI 0.39 to 0.80), 0.59 (0.43 to 0.81) and 0.49 (0.29 to 0.82) in the low-risk, intermediate-risk and high-risk groups, respectively. Compared with the general population, CRC incidence without surveillance was similar among low-risk (SIR 0.86, 95% CI 0.73 to 1.02) and intermediate-risk (1.16, 0.97 to 1.37) patients, but higher among high-risk patients (1.91, 1.39 to 2.56). CONCLUSION: Postpolypectomy surveillance reduces CRC risk. However, even without surveillance, CRC risk in some low-risk and intermediate-risk patients is no higher than in the general population. These patients could be managed by screening rather than surveillance.
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Adenoma , Neoplasias del Colon , Pólipos del Colon , Colonoscopía , Neoplasias Colorrectales , Ajuste de Riesgo , Adenoma/patología , Adenoma/cirugía , Anciano , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Pólipos del Colon/patología , Pólipos del Colon/cirugía , Colonoscopía/métodos , Colonoscopía/estadística & datos numéricos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/estadística & datos numéricos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Estudios Retrospectivos , Ajuste de Riesgo/métodos , Ajuste de Riesgo/organización & administración , Medición de Riesgo/métodos , Medición de Riesgo/estadística & datos numéricos , Factores de Riesgo , Reino Unido/epidemiologíaRESUMEN
BACKGROUND: In the UK, patients with one or two adenomas, of which at least one is ≥ 10 mm in size, or three or four small adenomas, are deemed to be at intermediate risk of colorectal cancer (CRC) and referred for surveillance colonoscopy 3 years post polypectomy. However, colonoscopy is costly, can cause discomfort and carries a small risk of complications. OBJECTIVES: To determine whether or not annual faecal immunochemical tests (FITs) are effective, acceptable and cost saving compared with colonoscopy surveillance for detecting CRC and advanced adenomas (AAs). DESIGN: Diagnostic accuracy study with health psychology assessment and economic evaluation. SETTING: Participants were recruited from 30 January 2012 to 30 December 2013 within the Bowel Cancer Screening Programme in England. PARTICIPANTS: Men and women, aged 60-72 years, deemed to be at intermediate risk of CRC following adenoma removal after a positive guaiac faecal occult blood test were invited to participate. Invitees who consented and returned an analysable FIT were included. INTERVENTION: We offered participants quantitative FITs at 1, 2 and 3 years post polypectomy. Participants testing positive with any FIT were referred for colonoscopy and not offered further FITs. Participants testing negative were offered colonoscopy at 3 years post polypectomy. Acceptibility of FIT was assessed using discussion groups, questionnaires and interviews. MAIN OUTCOME MEASURES: The primary outcome was 3-year sensitivity of an annual FIT versus colonoscopy at 3 years for detecting advanced colorectal neoplasia (ACN) (CRC and/or AA). Secondary outcomes included participants' surveillance preferences, and the incremental costs and cost-effectiveness of FIT versus colonoscopy surveillance. RESULTS: Of 8008 invitees, 5946 (74.3%) consented and returned a round 1 FIT. FIT uptake in rounds 2 and 3 was 97.2% and 96.9%, respectively. With a threshold of 40 µg of haemoglobin (Hb)/g faeces (hereafter referred to as µg/g), positivity was 5.8% in round 1, declining to 4.1% in round 3. Over three rounds, 69.2% (18/26) of participants with CRC, 34.3% (152/443) with AAs and 35.6% (165/463) with ACN tested positive at 40 µg/g. Sensitivity for CRC and AAs increased, whereas specificity decreased, with lower thresholds and multiple rounds. At 40 µg/g, sensitivity and specificity of the first FIT for CRC were 30.8% and 93.9%, respectively. The programme sensitivity and specificity of three rounds at 10 µg/g were 84.6% and 70.8%, respectively. Participants' preferred surveillance strategy was 3-yearly colonoscopy plus annual FITs (57.9%), followed by annual FITs with colonoscopy in positive cases (31.5%). FIT with colonoscopy in positive cases was cheaper than 3-yearly colonoscopy (£2,633,382), varying from £485,236 (40 µg/g) to £956,602 (10 µg/g). Over 3 years, FIT surveillance could miss 291 AAs and eight CRCs using a threshold of 40 µg/g, or 189 AAs and four CRCs using a threshold of 10 µg/g. CONCLUSIONS: Annual low-threshold FIT with colonoscopy in positive cases achieved high sensitivity for CRC and would be cost saving compared with 3-yearly colonoscopy. However, at higher thresholds, this strategy could miss 15-30% of CRCs and 40-70% of AAs. Most participants preferred annual FITs plus 3-yearly colonoscopy. Further research is needed to define a clear role for FITs in surveillance. FUTURE WORK: Evaluate the impact of ACN missed by FITs on quality-adjusted life-years. TRIAL REGISTRATION: Current Controlled Trials ISRCTN18040196. FUNDING: National Institute for Health Research (NIHR) Health Technology Assessment programme, NIHR Imperial Biomedical Research Centre and the Bobby Moore Fund for Cancer Research UK. MAST Group Ltd provided FIT kits.
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Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer/economía , Detección Precoz del Cáncer/métodos , Sangre Oculta , Anciano , Colonoscopía/economía , Colonoscopía/métodos , Análisis Costo-Beneficio , Detección Precoz del Cáncer/psicología , Detección Precoz del Cáncer/normas , Femenino , Conocimientos, Actitudes y Práctica en Salud , Hemoglobinas/análisis , Humanos , Inmunoquímica/economía , Inmunoquímica/métodos , Masculino , Persona de Mediana Edad , Prioridad del Paciente , Sensibilidad y Especificidad , Reino UnidoRESUMEN
OBJECTIVE: The English Bowel Cancer Screening Programme (BCSP) recommends 3 yearly colonoscopy surveillance for patients at intermediate risk of colorectal cancer (CRC) postpolypectomy (those with three to four small adenomas or one ≥10 mm). We investigated whether faecal immunochemical tests (FITs) could reduce surveillance burden on patients and endoscopy services. DESIGN: Intermediate-risk patients (60-72 years) recommended 3 yearly surveillance were recruited within the BCSP (January 2012-December 2013). FITs were offered at 1, 2 and 3 years postpolypectomy. Invitees consenting and returning a year 1 FIT were included. Participants testing positive (haemoglobin ≥40 µg/g) at years one or two were offered colonoscopy early; all others were offered colonoscopy at 3 years. Diagnostic accuracy for CRC and advanced adenomas (AAs) was estimated considering multiple tests and thresholds. We calculated incremental costs per additional AA and CRC detected by colonoscopy versus FIT surveillance. RESULTS: 74% (5938/8009) of invitees were included in our study having participated at year 1. Of these, 97% returned FITs at years 2 and 3. Three-year cumulative positivity was 13% at the 40 µg/g haemoglobin threshold and 29% at 10 µg/g. 29 participants were diagnosed with CRC and 446 with AAs. Three-year programme sensitivities for CRC and AAs were, respectively, 59% and 33% at 40 µg/g, and 72% and 57% at 10 µg/g. Incremental costs per additional AA and CRC detected by colonoscopy versus FIT (40 µg/g) surveillance were £7354 and £180 778, respectively. CONCLUSIONS: Replacing 3 yearly colonoscopy surveillance in intermediate-risk patients with annual FIT could reduce colonoscopies by 71%, significantly cut costs but could miss 30%-40% of CRCs and 40%-70% of AAs. TRIAL REGISTRATION NUMBER: ISRCTN18040196; Results.
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Pólipos del Colon/cirugía , Colonoscopía/métodos , Detección Precoz del Cáncer/métodos , Sangre Oculta , Adenoma/diagnóstico , Adenoma/cirugía , Anciano , Pólipos del Colon/diagnóstico , Colonoscopía/economía , Neoplasias Colorrectales/diagnóstico , Análisis Costo-Beneficio , Detección Precoz del Cáncer/economía , Inglaterra , Reacciones Falso Negativas , Femenino , Costos de la Atención en Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Vigilancia de la Población/métodos , Valor Predictivo de las Pruebas , Sensibilidad y EspecificidadRESUMEN
Replication is not as continuous as once thought, with DNA damage frequently stalling replication forks. Aberrant repair of stressed replication forks can result in cell death or genome instability and resulting transformation to malignancy. Stressed replication forks are most commonly repaired via homologous recombination (HR), which begins with 5' end resection, mediated by exonuclease complexes, one of which contains Exo1. However, Exo1 requires free 5'-DNA ends upon which to act, and these are not commonly present in non-reversed stalled replication forks. To generate a free 5' end, stalled replication forks must therefore be cleaved. Although several candidate endonucleases have been implicated in cleavage of stalled replication forks to permit end resection, the identity of such an endonuclease remains elusive. Here we show that the 5'-endonuclease EEPD1 cleaves replication forks at the junction between the lagging parental strand and the unreplicated DNA parental double strands. This cleavage creates the structure that Exo1 requires for 5' end resection and HR initiation. We observed that EEPD1 and Exo1 interact constitutively, and Exo1 repairs stalled replication forks poorly without EEPD1. Thus, EEPD1 performs a gatekeeper function for replication fork repair by mediating the fork cleavage that permits initiation of HR-mediated repair and restart of stressed forks.
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Reparación del ADN , Replicación del ADN , Endodesoxirribonucleasas/metabolismo , Células HEK293 , HumanosRESUMEN
Background. Serum magnesium levels affect the concentration of circulating vitamin D in blood and subsequently it affects the immunity; thus it plays significant role in the pathogenesis of asthma. Asthma, in adults, is less studied and hypomagnesemia along with vitamin D deficiency and insufficiency is common in asthmatic individuals, which causes frequent asthma attacks, respiratory infections, severe exacerbations, and poor response to bronchodilators. Objective. To detect the magnitude of vitamin D insufficiency and deficiency and serum magnesium levels among asthmatic patients and to correlate them with the severity of asthma. Materials and Methods. This is a cross-sectional case-control study which includes 60 patients of chronic stable asthma and 60 healthy controls. After taking clinical history and systemic examination, pulmonary function test was done. Serum levels of magnesium, 25-hydroxycholecalciferol [25(OH)D], and calcium were measured in all the subjects. Results. Significant correlation was found between vitamin D deficiency, hypomagnesemia, and asthma severity. Serum calcium levels were unaffected by that. Conclusion. Vitamin D and serum magnesium deficiency are highly prevalent in patients with asthma. Increased asthma severity, frequency of attacks, and exacerbation are associated with lower levels of one or both. Serum 25(OH)D and magnesium levels may serve as important markers of asthma severity.
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Asma , Broncodilatadores/uso terapéutico , Deficiencia de Magnesio , Magnesio/sangre , Deficiencia de Vitamina D , Vitamina D/sangre , Adulto , Asma/sangre , Asma/epidemiología , Asma/fisiopatología , Asma/terapia , Estudios Transversales , Progresión de la Enfermedad , Resistencia a Medicamentos , Femenino , Humanos , India/epidemiología , Deficiencia de Magnesio/diagnóstico , Deficiencia de Magnesio/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Pruebas de Función Respiratoria/métodos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Estadística como Asunto , Brote de los Síntomas , Deficiencia de Vitamina D/diagnóstico , Deficiencia de Vitamina D/epidemiologíaRESUMEN
Trithorax proteins and long-intergenic noncoding RNAs are critical regulators of embryonic stem cell pluripotency; however, how they cooperatively regulate germ layer mesoderm specification remains elusive. We report here that HoxBlinc RNA first specifies Flk1(+) mesoderm and then promotes hematopoietic differentiation through regulation of hoxb pathways. HoxBlinc binds to the hoxb genes, recruits Setd1a/MLL1 complexes, and mediates long-range chromatin interactions to activate transcription of the hoxb genes. Depletion of HoxBlinc by shRNA-mediated knockdown or CRISPR-Cas9-mediated genetic deletion inhibits expression of hoxb genes and other factors regulating cardiac/hematopoietic differentiation. Reduced hoxb expression is accompanied by decreased recruitment of Set1/MLL1 and H3K4me3 modification, as well as by reduced chromatin loop formation. Re-expression of hoxb2-b4 genes in HoxBlinc-depleted embryoid bodies rescues Flk1(+) precursors that undergo hematopoietic differentiation. Thus, HoxBlinc plays an important role in controlling hoxb transcription networks that mediate specification of mesoderm-derived Flk1(+) precursors and differentiation of Flk1(+) cells into hematopoietic lineages.
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Linaje de la Célula/fisiología , Embrión de Mamíferos/metabolismo , Regulación del Desarrollo de la Expresión Génica/fisiología , N-Metiltransferasa de Histona-Lisina/metabolismo , Proteínas de Homeodominio/biosíntesis , Mesodermo/embriología , Proteína de la Leucemia Mieloide-Linfoide/metabolismo , ARN Largo no Codificante/biosíntesis , Animales , Línea Celular , Embrión de Mamíferos/citología , N-Metiltransferasa de Histona-Lisina/genética , Proteínas de Homeodominio/genética , Mesodermo/citología , Ratones , Complejos Multienzimáticos/genética , Complejos Multienzimáticos/metabolismo , Proteína de la Leucemia Mieloide-Linfoide/genética , ARN Largo no Codificante/genéticaRESUMEN
Replication fork stalling and collapse is a major source of genome instability leading to neoplastic transformation or cell death. Such stressed replication forks can be conservatively repaired and restarted using homologous recombination (HR) or non-conservatively repaired using micro-homology mediated end joining (MMEJ). HR repair of stressed forks is initiated by 5' end resection near the fork junction, which permits 3' single strand invasion of a homologous template for fork restart. This 5' end resection also prevents classical non-homologous end-joining (cNHEJ), a competing pathway for DNA double-strand break (DSB) repair. Unopposed NHEJ can cause genome instability during replication stress by abnormally fusing free double strand ends that occur as unstable replication fork repair intermediates. We show here that the previously uncharacterized Exonuclease/Endonuclease/Phosphatase Domain-1 (EEPD1) protein is required for initiating repair and restart of stalled forks. EEPD1 is recruited to stalled forks, enhances 5' DNA end resection, and promotes restart of stalled forks. Interestingly, EEPD1 directs DSB repair away from cNHEJ, and also away from MMEJ, which requires limited end resection for initiation. EEPD1 is also required for proper ATR and CHK1 phosphorylation, and formation of gamma-H2AX, RAD51 and phospho-RPA32 foci. Consistent with a direct role in stalled replication fork cleavage, EEPD1 is a 5' overhang nuclease in an obligate complex with the end resection nuclease Exo1 and BLM. EEPD1 depletion causes nuclear and cytogenetic defects, which are made worse by replication stress. Depleting 53BP1, which slows cNHEJ, fully rescues the nuclear and cytogenetic abnormalities seen with EEPD1 depletion. These data demonstrate that genome stability during replication stress is maintained by EEPD1, which initiates HR and inhibits cNHEJ and MMEJ.
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ADN Helicasas/genética , Endodesoxirribonucleasas/genética , Inestabilidad Genómica , Recombinación Homóloga/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Reparación del ADN por Recombinación/genética , Roturas del ADN de Doble Cadena , Daño del ADN/genética , Reparación del ADN por Unión de Extremidades/genética , Proteínas de Escherichia coli/genética , Regulación de la Expresión Génica , Células HEK293 , Histonas/genética , Humanos , Proteína 1 de Unión al Supresor Tumoral P53RESUMEN
Child abuse and neglect remains a major cause of morbidity and mortality among children worldwide. Over the last few decades, there has been growing research in the field of Child Abuse Pediatrics with greater recognition and research into potential diagnostic mimics of inflicted injury. This paper reviews some common skin findings and bleeding disorders that have features in common with child abuse.
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Maltrato a los Niños/diagnóstico , Contusiones/diagnóstico , Hemorragia/diagnóstico , Enfermedades de la Piel/diagnóstico , Niño , Preescolar , Contusiones/genética , Contusiones/patología , Diagnóstico Diferencial , Hemorragia/etiología , Hemorragia/patología , Humanos , Enfermedades de la Piel/genética , Enfermedades de la Piel/patologíaRESUMEN
Circadian rhythms govern all biological functions. Circadian misalignment has a major impact on health. Late chronotype is a risk factor for circadian misalignment which in turn can affect the control of seizures in epilepsy patients. We compared a group of 87 confirmed epilepsy patients regardless of subtypes with age- and sex-matched healthy controls. We compared generalized epilepsy patients with localization related epilepsy patients and with healthy controls. We found that primary generalized epilepsy patients were 5 times more likely to have a late chronotype than healthy controls. We did not find any significant differences between localization related epilepsy patients and healthy controls or between the overall epilepsy cohort and healthy controls. Generalized epilepsy patients are more likely to be evening types as compared to those with focal epilepsy or subjects without epilepsy. Epilepsy patients do not experience the same age related increase in morningness as do age-matched healthy controls. This is important in regard to timing of AED, identifying and preventing sleep deprivation, and integrating chronotype evaluations and chronotherapy in comprehensive epilepsy care. Further studies, using objective phase markers or the impact of chronotherapy on seizure control, are necessary.
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Ritmo Circadiano/fisiología , Epilepsia/fisiopatología , Privación de Sueño/fisiopatología , Sueño/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Encuestas y Cuestionarios , Adulto JovenRESUMEN
INTRODUCTION: Obesity is a condition in which excess body fat accumulates, which leads to various adverse effects on health, particularly cardiovascular diseases (CVDs), which reduce life expectancy and/or increase health problems. Fast food consumption is one of the factors which have been reported as a cause of obesity. Body mass index (BMI) is used to assess obesity and overweight, which can be calculated by using the formula, weight in kg, divided by square of height in metres. AIM: This study focused on the relationship of body mass index with fast food consumption, associated soft drink consumption and physical activity. METHODS: Descriptive cross-sectional study was conducted in Department of Biochemistry, SBKS MI and RC, and Sumandeep Vidyapeeth. This study was approved by the ethical review board .One hundred and forty seven medical students from 1(st) year MBBS course were included in this study. Self-structured questionnaire was used, which contained several data like information on age, height, weight, education level. The formula used for calculating BMI was, weight in kg, divided by square of height in metres (Kg/m(2)). RESULTS: In our study, out of 147 students, a total of 138 students (more than 90%) used to have fast food. Among these, a total of 47 students (34.05%) were pre-obese and obese. Out of 147 students, 87 students (59.18%) were in normal weight range, while 13 (8.84%) students were underweight. STATISTICAL ANALYSIS: Data was compiled in an Excel worksheet and it was analyzed for percentages and proportions. Chi-square and Pearson's correlation test were also applied wherever they were applicable and Alpha error was set at a 5% level. CONCLUSION: In our study, a significant relationship was found between BMI and fast food consumption, less physical activity, and intake of soft drinks.
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The abundance and structure of denitrifying bacterial community in different activated sludge samples were assessed, where the abundance of denitrifying functional genes showed nirS in the range of 10(4)-10(5), nosZ with 10(4)-10(6) and 16S rRNA gene in the range 10(9)-10(10) copy number per ml of sludge. The culturable approach revealed Pseudomonas sp. and Alcaligenes sp. to be numerically high, whereas culture independent method showed betaproteobacteria to dominate the sludge samples. Comamonas sp. and Pseudomonas fluorescens isolates showed efficient denitrification, while Pseudomonas mendocina, Pseudomonas stutzeri and Brevundimonas diminuta accumulated nitrite during denitrification. Numerically dominant RFLP OTUs of the nosZ gene from the fertilizer factory sludge samples clustered with the known isolates of betaproteobacteria. The data also suggests the presence of different truncated denitrifiers with high numbers in sludge habitat.
Asunto(s)
Bacterias/aislamiento & purificación , Desnitrificación , Aguas del Alcantarillado/microbiología , Bacterias/clasificación , Bacterias/metabolismo , Secuencia de Bases , Biodiversidad , Cartilla de ADN , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de RestricciónRESUMEN
Histone modifications play an important role in the process of transcription. However, in contrast to lysine methylation, the role of arginine methylation in chromatin structure and transcription has been underexplored. The globin genes are regulated by a highly organized chromatin structure that juxtaposes the locus control region (LCR) with downstream globin genes. We report here that the targeted recruitment of asymmetric dimethyl H4R3 catalyzed by PRMT1 (protein arginine methyltransferase 1) facilitates histone H3 acetylation on Lys9/Lys14. Dimethyl H4R3 provides a binding surface for P300/CBP-associated factor (PCAF) and directly enhances histone H3 acetylation in vitro. We show that these active modifications are essential for efficient interactions between the LCR and the beta(maj)-promoter as well as transcription of the beta-globin gene. Furthermore, knockdown (KD) of PRMT1 by RNA interference in erythroid progenitor cells prevents histone acetylation, enhancer and promoter interaction, and recruitment of transcription complexes to the active beta-globin promoter. Reintroducing rat PRMT1 into the PRMT1 KD MEL cells rescues PRMT1 binding, beta-globin transcription, and erythroid differentiation. Taken together, our data suggest that PRMT1-mediated dimethyl H4R3 facilitates histone acetylation and enhancer/promoter communications, which lead to the efficient recruitment of transcription preinitiation complexes to active promoters.
Asunto(s)
Histona Acetiltransferasas/metabolismo , N-Metiltransferasa de Histona-Lisina/fisiología , Histonas/metabolismo , Globinas beta/genética , Acetilación , Animales , Arginina/metabolismo , Células Cultivadas , Embrión de Mamíferos , Regulación del Desarrollo de la Expresión Génica/fisiología , Histona Acetiltransferasas/fisiología , Histona Metiltransferasas , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/fisiología , Metilación , Ratones , Unión Proteica/fisiología , Proteína-Arginina N-Metiltransferasas/antagonistas & inhibidores , Proteína-Arginina N-Metiltransferasas/genética , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína-Arginina N-Metiltransferasas/fisiología , Transcripción Genética , Globinas beta/metabolismoRESUMEN
This letter describes the architecture and transcriptional output of a novel noncoding RNA gene in mouse and rat. The mRNA-like piRNA (mpiR) gene, lies between the Perp and KIAA1244 genes on mouse chromosome 10 and rat chromosome 1. In mouse, the mpiR gene is associated with the production of at least 13 different alternatively spliced and polyadenylated transcripts ranging from 500 nt to over 6 kb. Although these transcripts are structurally similar to conventional mRNAs, only short polypeptides are predicted on each of the three possible reading frames. Intron 2 is unique in that it harbors a novel low copy repeat with homology with the 3'-UTR of the lin-28 gene, while Exon 4 contains an unusual cluster of nine sequence modules that are dispersed throughout the mouse genome. The mpiR gene is expressed at low levels in somatic tissues, but is transcriptionally up-regulated in the testis at day 14 post-partum, a time that coincides with the pachytene stage of meiosis I. Bisulfite methylation analysis shows that expression in brain, liver, and testis is correlated with the methylation status of the promoter region. In addition to mRNA-like transcripts, the mpiR gene is also a precursor to testis-specific piRNAs, and these can be detected by both Northern and PCR-based approaches. Remarkably, piRNAs originate from two specific regions of the gene, one corresponding to Intron 2 and the other to Exon 4. Overall, this work provides a picture of a novel, lineage-specific, noncoding RNA gene and describes its processing into both mRNA-like and piRNA products.