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1.
bioRxiv ; 2023 Dec 10.
Article in English | MEDLINE | ID: mdl-38106192

ABSTRACT

Chromothripsis, the process of catastrophic shattering and haphazard repair of chromosomes, is a common event in cancer. Whether chromothripsis might constitute an actionable molecular event amenable to therapeutic targeting remains an open question. We describe recurrent chromothripsis of chromosome 21 in a subset of patients in blast phase of a myeloproliferative neoplasm (BP-MPN), which alongside other structural variants leads to amplification of a region of chromosome 21 in ∼25% of patients ('chr21amp'). We report that chr21amp BP-MPN has a particularly aggressive and treatment-resistant phenotype. The chr21amp event is highly clonal and present throughout the hematopoietic hierarchy. DYRK1A , a serine threonine kinase and transcription factor, is the only gene in the 2.7Mb minimally amplified region which showed both increased expression and chromatin accessibility compared to non-chr21amp BP-MPN controls. We demonstrate that DYRK1A is a central node at the nexus of multiple cellular functions critical for BP-MPN development, including DNA repair, STAT signalling and BCL2 overexpression. DYRK1A is essential for BP-MPN cell proliferation in vitro and in vivo , and DYRK1A inhibition synergises with BCL2 targeting to induce BP-MPN cell apoptosis. Collectively, these findings define the chr21amp event as a prognostic biomarker in BP-MPN and link chromothripsis to a druggable target.

2.
Radiography (Lond) ; 29(5): 870-877, 2023 08.
Article in English | MEDLINE | ID: mdl-37419047

ABSTRACT

INTRODUCTION: To investigate the exposure parameters for thoracic spine/(TS) radiography that allows the image acquisition at the lowest dose possible, while maintaining an adequate image quality/(IQ) to identify all relevant anatomical criteria. METHODS: An experimental phantom study was conducted, and 48 different radiographs of TS (24 AP/24 lateral) were acquired. The Automatic Exposure Control/(AEC) with the central sensor was used to select the beam intensity, while Source-to-Detector-Distance/(SDD) (AP:115/125 cm; Lateral:115/150 cm), tube potential (AP:70/81/90 kVp; Lateral: 81/90/102 kVp), use of grid/no grid and focal spot (fine/broad) were manipulated. IQ was assessed by observers with ViewDEX. Effective Dose (ED) was estimated using PCXMC2.0 software. Descriptive statistics paired with intraclass correlation coefficient (ICC) were applied to analyse data. RESULTS: The ED increased with a greater SDD for lateral-view, presenting a significant difference (p = 0.038), however IQ was not affected. For both AP and lateral, the use of grid had a significant effect on ED (p < 0.001). Despite the images acquired without grid had lower IQ scores, the observers considered the IQ adequate for clinical use. A 20% reduction in ED (0.042mSv-0.033 mSv) was observed when increasing the beam energy from 70 to 90 kVp for AP grid in. The observers ICC ranged from moderate to good (0.5-0.75) in lateral and good to excellent (0.75-0.9) for AP views. CONCLUSIONS: The optimised parameters in this context were 115 cm SDD, 90 kVp with grid for the best IQ and lowest ED. Further studies in clinical setting are necessary to enlarge the context and cover different body habitus and equipment. IMPLICATIONS FOR PRACTICE: The SDD impacts on dose for TS; Higher kVp and grid are necessary to better image quality.


Subject(s)
Carmustine , Humans , Radiation Dosage , Radiography , Phantoms, Imaging
3.
Animal ; 13(3): 460-468, 2019 Mar.
Article in English | MEDLINE | ID: mdl-29976267

ABSTRACT

Polymorphisms in the growth hormone (GH) and IGF type-1 (IGF1) genes have been associated with the economic traits in farm animals, including BW of some sheep breeds. However, it remains unknown if these polymorphisms also affect carcass traits in sheep. Thus, we aimed to identify polymorphisms in the GH and IGF1 genes in Santa Ines sheep in order to describe their allelic and genotypic frequencies as well as to test the hypotheses that they are associated with the carcass traits. Fragments of 4550 bp (IGF1) and 1194 bp (GH) were sequenced in up to 191 lambs. In all, 18 polymorphisms were identified in the IGF1 and 21 in the GH gene. The IGF1 polymorphisms rs430457475, rs412470350, rs409110739 and rs400113576 showed an additive effect on the internal carcass length (-0.9265±0.4223), rump girth (-2.9285±1.1473), rib yield (-1.0003±0.4588) and neck weight (-0.0567±0.0278), respectively. In addition, the polymorphisms rs58957314 in the GH affected the rib weight (-0.4380±0.1272) and rib yield (-2.2680±0.6970), loin weight (-0.1893±0.0516) and loin yield (-0.9423±0.3259), palette weight (-0.2265±0.0779) and palette yield (-0.9424±0.4184), leg weight (-0.3960±0.1375), neck weight (-0.0851±0.0394) and carcass finishing score (-0.1700±0.0839). These results allow us to conclude that there are polymorphisms in the IGF1 and GH genes associated with carcass traits in Santa Ines sheep, which can provide important information for marker-assisted selection.


Subject(s)
Growth Hormone/genetics , Insulin-Like Growth Factor I/genetics , Polymorphism, Single Nucleotide , Sheep/physiology , Animals , Body Composition , Body Weight/genetics , Gene Expression Regulation , Genotype , Sheep/genetics
4.
Sci Total Environ ; 573: 1190-1202, 2016 Dec 15.
Article in English | MEDLINE | ID: mdl-27105667

ABSTRACT

Information on the spatial incidence of fire ignition density and burnt area, trends and drivers of wildfires is vitally important in providing support for environmental and civil protection policies, designing appropriate prevention measures and allocating firefighting resources. The key objectives of this study were to analyse the geographical incidence and temporal trends for wildfires, as well as the main drivers of fire ignition and burnt area in Portugal on a municipal level. The results show that fires are not distributed uniformly throughout Portuguese territory, both in terms of ignition density and burnt area. One spot in the north-western area is well defined, covering 10% of the municipalities where more than one third of the total fire ignitions are concentrated. In >80% of Portuguese municipalities, ignition density has registered a positive trend since the 1980s. With regard to burnt area, 60% of the municipalities had a nil annual trend, 35% showed a positive trend and 5%, located mainly in the central region, revealed negative trends. Geographically weighted regression proved more efficient in identifying the most relevant physical and anthropogenic drivers of municipal wildfires in comparison with simple linear regression models. Topography, density of population, land cover and livestock were found to be significant in both ignition density and burnt area, although considerable variations were observed in municipal explanatory power.

5.
Braz J Biol ; 72(4): 795-9, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23295506

ABSTRACT

This study observed the mosquito population in a rural eutrophised dam. Larvae of L3 and L4 stages and pupae were dipped out during twelve month collections and the reared to the adult stage for identification. The collections were done along nine metres from the edge of the dam divided in three parts (P1, P2 and P3), each part being 3 m long. P1 did not have vegetation (grass) along its edge,which would reach or sink into the water to promote some shade on the marginal water. A total of 217 adults of four species was identified with the following constancies and frequencies: Culex quinquefasciatus (Say, 1823) (83% and 40.6%), Anopheles (Nyssorhynchus) evansae (Brèthes, 1926) (92% and 26.7%), Anopheles (Nyssorhynchus) rangeli (Gabaldon, Cova Garcia and Lopez, 1940) (83% and 14.3%) and Culex nigripalpus (Theobald, 1901) (33% and 18.4%). C. quinquefasciatus, A. evansae, A. rangeli and C. nigripalpus were more frequent in the quarters Nov./Dec./Jan. (85.7%), May/June/July (75%), Aug./Sept./Oct. (29.4%) and Aug./Sept./Oct. (23.5%) particularly in the months of December (88.4%) Sept.tember (48.94), (38.3) and August (47.62) respectively. The presence of C. quinquefasciatus and the high incidence of Daphinia sp. and also the levels of Organic Nitrogen (0.28 mg/L) and of total Phosphorus (0.02 mg/L) are indications of the eutrophication of the dam. There was a difference regarding the total of Anopheles (A. avansae + A. rangeli) and Culex species (C. quinquefasciatus + C. nigripalpis) between P1 and P2 (χ(2) = 0.0097), P1 and P3 (χ(2) = 0.0005), but not between P2 and P3 (χ(2) = 0.2045).The high C. quinquefasciatus constancy and frequency were confirmed to be a good biological indicator for a eutrophised environment and A. evansae showed a good potential for this environment. Vegetation can be an important factor for anopheline population dynamic also in eutrophic breeding sites.


Subject(s)
Culicidae/physiology , Ecosystem , Animals , Brazil , Culicidae/classification , Eutrophication , Fresh Water , Population Dynamics , Rural Population , Seasons
6.
J Child Adolesc Psychopharmacol ; 15(2): 240-8, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15910208

ABSTRACT

OBJECTIVE: The aim of this study was to examine the association of age, race, insurance, and other factors with the prescription of stimulant medications. METHODS: A retrospective chart review was conducted on 242 subjects, 4.8-19.8 years of age, treated in an urban referral center with a stable dose of stimulant medication for at least 6 months. Subjects were predominantly male (74.8%), African-American (52.9%), and insured by Medicaid (71.0%). The effects of age, race, insurance, gender, cognitive level, additional psychopharmacologic medications, and other factors on prescribed total daily dose (mg/day) and dose by weight (mg/kg/dose) were examined. RESULTS: Race and insurance type together were associated with specific patterns of stimulant dosage, with higher dosing seen in Medicaid-insured non-African-American children and in privately insured African-American children. Total daily dose increased with age; however, there was an inverse relationship between age and dose by weight. There were no significant associations of gender, cognitive level, use of additional psychopharmacological medications, or other factors with total daily dose or dose by weight. CONCLUSIONS: The sociocultural factors of race and insurance type were related to dosing of stimulant medications in children. Total daily doses increased with age, while younger children were treated with higher weight-based doses. Attention to these factors should be given in the titration of stimulant medications in the treatment of ADHD. Other factors, including gender, had no specific association.


Subject(s)
Attention Deficit Disorder with Hyperactivity/drug therapy , Attention Deficit Disorder with Hyperactivity/epidemiology , Black or African American/statistics & numerical data , Central Nervous System Stimulants/administration & dosage , Insurance, Health/statistics & numerical data , White People/statistics & numerical data , Adolescent , Adult , Age Factors , Attention Deficit Disorder with Hyperactivity/economics , Child , Child, Preschool , Female , Humans , Insurance, Health/economics , Male , Retrospective Studies , Socioeconomic Factors
7.
J Child Adolesc Psychopharmacol ; 13(1): 103-6, 2003.
Article in English | MEDLINE | ID: mdl-12804131

ABSTRACT

Although attention deficit hyperactivity disorder is thought to be present in preschoolers, there are no clear guidelines for dosing stimulant medications in this population. This is a case of a 4-year-old boy who was given 108 mg/day extended-release methylphenidate (OROS) MPH) (6.1 mg/kg/day) by his caregiver with notable behavioral improvement. However, weight loss incurred due to the anorexic side effect of the medication led the clinician to decrease his dose to 72 mg/day OROS MPH (3.7 mg/kg/day). The case highlights that some young children with attention deficit hyperactivity disorder treated with MPH may require higher doses than would be predicted by weight-based dosing. An increased frequency of side effects associated with high doses of MPH necessitates that the clinician balance the positive behavioral response of the medication with adverse side effects in determining ideal dose.


Subject(s)
Attention Deficit Disorder with Hyperactivity/drug therapy , Central Nervous System Stimulants/administration & dosage , Methylphenidate/administration & dosage , Attention Deficit Disorder with Hyperactivity/psychology , Central Nervous System Stimulants/adverse effects , Central Nervous System Stimulants/therapeutic use , Child Behavior/drug effects , Child, Preschool , Humans , Male , Methylphenidate/adverse effects , Methylphenidate/therapeutic use , Treatment Outcome , Weight Loss
8.
Breast ; 9(6): 315-9, 2000 Dec.
Article in English | MEDLINE | ID: mdl-14965754

ABSTRACT

Squamous carcinoma of the breast (SCB) is a rare entity. For its diagnosis, the exclusion of squamous cell carcinoma of local cutaneous structures and metastasis of distant squamous carcinoma are mandatory. The aim was to retrospectively evaluate the prevalence, epidemiological and clinical characteristics of the cases of SCB, studied in our institution, between January 1985 and December 1996. The diagnosis was histopathological. We studied the patients' demographic data and tumour characteristics. In the 11-year study period, 5791 patients with breast carcinoma were admitted to our Institution, seven (0.1%) of which were SCB. All seven patients were female and Caucasian. Their average age was 63 years (range 24-82). The presentation was always a breast lump. Five patients were in Stage II-A and two in Stage II-B. All tumours were hormone-receptor negative. The initial treatment was surgery and four patients received adjuvant radiotherapy. The median follow-up was 64 months. No relapses were diagnosed. SCB is a rare entity. The initial therapeutic approach should be surgical. There is still no consensus regarding adjuvant therapy. The prognosis of this type of breast cancer is still the subject of controversy with some series, including the present study, suggesting an indolent clinical course and a relatively good prognosis.

9.
Braz J Med Biol Res ; 29(12): 1709-13, 1996 Dec.
Article in English | MEDLINE | ID: mdl-9222436

ABSTRACT

In order to study the probable physiological role of non-activated lymphocytes on islet B-cells, we incubated and perfused rat pancreatic islets in the presence of low (2.8 mM) and high (16.7 mM) glucose concentrations after pre-exposure for 60 min to rat lymphocytes or to substances secreted by lymphocytes. Insulin secretion and 86Rb+, 45Ca2+ and [3H]-phosphoinositide metabolite fluxes were lower compared to controls when islets were pre-exposed to lymphocytes but were not different when islets were pre-exposed to substances secreted by lymphocytes. These alterations in isotope flux suggest that, when lymphocytes and islets are in contact, closure of potassium channels and a paradoxical effect of glucose load on insulin release occur in the presence of low glucose concentrations. The alterations observed are probably due to a swift and direct action of lymphocyte secretion perhaps induced by a direct of islet cells.


Subject(s)
Insulin/metabolism , Lymphocytes/metabolism , Animals , Insulin Secretion , Islets of Langerhans , Male , Rats
10.
Braz. j. med. biol. res ; 29(12): 1709-13, Dec. 1996. graf
Article in English | LILACS | ID: lil-188458

ABSTRACT

In order to study the probable physiological role of non-activated lymphocytes on islet B-cells, we incubated and perfused rat pancreatic islets in the presence of low (2.8 mM) and high (l6.7 mM) glucose concentrations after pre-exposure for 60 min to rat lymphocytes or to substances secreted by lymphocytes. Insulin secretion and 86Rb+, 45Ca2+ and [3H]-phosphoinositide metabolite fluxes were lower compared to controls when islets were pre-exposed to lymphocytes but were not different when islets were pre-exposed to substances secreted by lymphocytes. These alterations in isotope flux suggest that, when lymphocytes and islets are in contact, closure of potassium channels and a paradoxical effect of glucose load on insulin release occur in the presence of low glucose concentrations. The alterations observed are probably due to a swift and direct action of lymphocyte secretion perhaps induced by a direct contact of islet cells.


Subject(s)
Rats , Animals , Male , In Vitro Techniques , Insulin/physiology , Insulin/metabolism , Lymphocytes/physiology , Islets of Langerhans
11.
Rev Saude Publica ; 27(5): 388-90, 1993 Oct.
Article in Portuguese | MEDLINE | ID: mdl-8209174

ABSTRACT

An ethical opinion survey was carried out among Brazilian physicians regarding artificial insemination. The results showed no statistical difference between opinions of physicians from the various regions of the country.


Subject(s)
Attitude of Health Personnel , Ethics, Medical , Insemination, Artificial , Physicians , Brazil , Social Values
12.
Rev Paul Med ; 110(4): 173-6, 1992.
Article in English | MEDLINE | ID: mdl-1341007

ABSTRACT

A careful literature review of the use of vaginal fluid acid phosphatase levels as a means to estimate post-coital time disclosed several inconsistencies. In this study, acid phosphatase levels were determined in vaginal fluid samples obtained from 200 women whose post-coital time was known. No statistical significance (at 5% probability levels) was found when vaginal acid phosphatase levels were correlated with post-coital time.


Subject(s)
Acid Phosphatase/analysis , Coitus , Vagina/enzymology , Female , Humans , Linear Models , Sensitivity and Specificity , Time Factors
13.
Rev. paul. med ; 110(1): 34-8, jan.-fev. 1992. tab, ilus
Article in English | LILACS | ID: lil-116199

ABSTRACT

Th joint analysis of several genetic markers in casesof paternity investigation renders possible a cumulative probability of 99.7% of change of esclusion of a flasely accused father. The role of heteromorphism of the Y chromosome size was appraised in this work, with more than one genetic marker, in 20 expertise examinations in paternity investigation, where the children were male. The results found with found with this method, in association with the research on erythrocytic and leucocytic antigens showed the exclusion of two falsely accused men. Cytogenetic analysis with Giemsa stain in combination with leukocyte (HLA system) and erithrocyte antigens investigation demonstrated the exclusion of two men falsely accused


Subject(s)
Humans , Male , Female , Paternity , Cytogenetics , Y Chromosome , Erythrocytes , HLA Antigens/genetics , Genetic Markers , False Positive Reactions
14.
Rev Paul Med ; 110(1): 34-8, 1992.
Article in English | MEDLINE | ID: mdl-1307139

ABSTRACT

The joint analysis of several genetic markers in cases of paternity investigation renders possible a cumulative probability of 99.7% of chance of exclusion of a falsely accused father. The role of heteromorphisms of the Y chromosome size was appraised in this work, with more than one genetic marker, in 20 expertise examinations in paternity investigation, where the children were male. The results found with this method, in association with the research on erythrocytic and leucocytic antigens showed the exclusion of two falsely accused men. Cytogenetics analysis with Giemsa stain in combination with leukocyte (HLA system) and erythrocyte antigens investigation demonstrated the exclusion of two men falsely accused.


Subject(s)
Cytogenetics , Paternity , Erythrocytes , False Positive Reactions , Female , Genetic Markers , HLA Antigens/genetics , Humans , Male , Y Chromosome
15.
Rev Paul Med ; 109(3): 131-3, 1991.
Article in Portuguese | MEDLINE | ID: mdl-1947609

ABSTRACT

The author justifies his work showing the need for standardization in experiments involving human beings. Major international and Brazilian regulations to that effect are referred to in order to establish main items that should guide an experimentation with human beings under ethical requirements.


Subject(s)
Ethics, Medical , Human Experimentation , Legislation, Medical , Brazil , Humans
16.
Rev Paul Med ; 108(2): 78-82, 1990.
Article in Portuguese | MEDLINE | ID: mdl-2259824

ABSTRACT

The Y-chromatin is visualized in human interphase nuclei, corresponding to the distal portion of the Y-chromosome, which shows marked fluorescence after staining with quinacrine. This report describes the results of sex determination on blood smears fixed in methanol and blood stains left at room temperature for 13 weeks (1st report), and for 10 months (2nd report). Blind trials showed that a reliable sex determination of blood stains on glass left for at least six months is possible. The application of this method in forensic practice is discussed.


Subject(s)
Forensic Medicine , Sex Chromatin , Sex Determination Analysis , Y Chromosome/chemistry , Blood Stains , Female , Humans , Interphase , Male
17.
Rev Saude Publica ; 23(6): 465-72, 1989 Dec.
Article in Portuguese | MEDLINE | ID: mdl-2641838

ABSTRACT

The results of a survey carried out with the participation of 155 medical and 141 law students are given. Of the total of 296 students, 142 agreed with the freeing of abortion from legal restrictions, 144 agreed with such restrictions and 6 gave no opinion. Of the 144, 12 rejected abortion under any circumstances. The differences were analysed by sex and school. The statistical analysis did not show significance at the level of 5%.


Subject(s)
Abortion, Legal , Attitude to Health , Legislation, Medical , Students, Medical , Abortion, Eugenic , Brazil , Female , Humans , Male , Pregnancy
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