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1.
Arch Suicide Res ; : 1-11, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37013700

RESUMO

OBJECTIVE: The objective of this study was to identify baseline demographic and clinical factors associated with higher scores on the Reasons for Living Inventory for Adolescents (RFL-A) at baseline and over follow-up. METHOD: Using data from a pilot clinical trial of a brief intervention for suicidal youth transitioning from inpatient to outpatient, we identified univariate associations of baseline characteristics with RFL-A and used regression to identify the most parsimonious subset of these variables. Finally, we examined to what extent changes in these characteristics over time were related to changes in RFL-A. RESULTS: Univariate analyses found that better external functional emotion regulation and social support were associated with higher RFL-A scores; more self-reported depression, internal dysfunctional emotion regulation, sleep disturbance, anxiety, and distress tolerance were associated with lower RFL-A scores. Multiple linear regression identified internal dysfunctional emotion regulation and external functional emotion regulation as the most parsimonious set of characteristics associated with RFL-A. Improvement in internal emotion regulation, sleep, and depression were related to improvements in RFL-A over time. CONCLUSION: Our findings indicate that emotion regulation-specifically maladaptive internal strategies and use of external resources-is strongly associated with RFL-A. Improvements in internal emotion regulation (r = 0.57), sleep (r = -0.45), and depression (r = -0.34) were related to increases in RFL-A.HIGHLIGHTSIn the literature, greater reasons for living are associated with lower risk for future suicidal ideation and suicide attempts.The most salient correlate of concurrent and future lower RFL-A was dysfunctional internal emotion regulation. Improved sleep and decreases in depression were correlated with increases in RFL-A.

2.
Stud Mycol ; 105: 1-22, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38895705

RESUMO

The subphylum Saccharomycotina is a lineage in the fungal phylum Ascomycota that exhibits levels of genomic diversity similar to those of plants and animals. The Saccharomycotina consist of more than 1 200 known species currently divided into 16 families, one order, and one class. Species in this subphylum are ecologically and metabolically diverse and include important opportunistic human pathogens, as well as species important in biotechnological applications. Many traits of biotechnological interest are found in closely related species and often restricted to single phylogenetic clades. However, the biotechnological potential of most yeast species remains unexplored. Although the subphylum Saccharomycotina has much higher rates of genome sequence evolution than its sister subphylum, Pezizomycotina, it contains only one class compared to the 16 classes in Pezizomycotina. The third subphylum of Ascomycota, the Taphrinomycotina, consists of six classes and has approximately 10 times fewer species than the Saccharomycotina. These data indicate that the current classification of all these yeasts into a single class and a single order is an underappreciation of their diversity. Our previous genome-scale phylogenetic analyses showed that the Saccharomycotina contains 12 major and robustly supported phylogenetic clades; seven of these are current families (Lipomycetaceae, Trigonopsidaceae, Alloascoideaceae, Pichiaceae, Phaffomycetaceae, Saccharomycodaceae, and Saccharomycetaceae), one comprises two current families (Dipodascaceae and Trichomonascaceae), one represents the genus Sporopachydermia, and three represent lineages that differ in their translation of the CUG codon (CUG-Ala, CUG-Ser1, and CUG-Ser2). Using these analyses in combination with relative evolutionary divergence and genome content analyses, we propose an updated classification for the Saccharomycotina, including seven classes and 12 orders that can be diagnosed by genome content. This updated classification is consistent with the high levels of genomic diversity within this subphylum and is necessary to make the higher rank classification of the Saccharomycotina more comparable to that of other fungi, as well as to communicate efficiently on lineages that are not yet formally named. Taxonomic novelties: New classes: Alloascoideomycetes M. Groenew., Hittinger, Opulente & A. Rokas, Dipodascomycetes M. Groenew., Hittinger, Opulente & A. Rokas, Lipomycetes M. Groenew., Hittinger, Opulente, A. Rokas, Pichiomycetes M. Groenew., Hittinger, Opulente & A. Rokas, Sporopachydermiomycetes M. Groenew., Hittinger, Opulente & A. Rokas, Trigonopsidomycetes M. Groenew., Hittinger, Opulente & A. Rokas. New orders: Alloascoideomycetes: Alloascoideales M. Groenew., Hittinger, Opulente & A. Rokas; Dipodascomycetes: Dipodascales M. Groenew., Hittinger, Opulente & A. Rokas; Lipomycetes: Lipomycetales M. Groenew., Hittinger, Opulente & A. Rokas; Pichiomycetes: Alaninales M. Groenew., Hittinger, Opulente & A. Rokas, Pichiales M. Groenew., Hittinger, Opulente & A. Rokas, Serinales M. Groenew., Hittinger, Opulente & A. Rokas; Saccharomycetes: Phaffomycetales M. Groenew., Hittinger, Opulente & A. Rokas, Saccharomycodales M. Groenew., Hittinger, Opulente & A. Rokas; Sporopachydermiomycetes: Sporopachydermiales M. Groenew., Hittinger, Opulente & A. Rokas; Trigonopsidomycetes: Trigonopsidales M. Groenew., Hittinger, Opulente & A. Rokas. New families: Alaninales: Pachysolenaceae M. Groenew., Hittinger, Opulente & A. Rokas; Pichiales: Pichiaceae M. Groenew., Hittinger, Opulente & A. Rokas; Sporopachydermiales: Sporopachydermiaceae M. Groenew., Hittinger, Opulente & A. Rokas. Citation: Groenewald M, Hittinger CT, Bensch K, Opulente DA, Shen X-X, Li Y, Liu C, LaBella AL, Zhou X, Limtong S, Jindamorakot S, Gonçalves P, Robert V, Wolfe KH, Rosa CA, Boekhout T, Cadez N, Péter G, Sampaio JP, Lachance M-A, Yurkov AM, Daniel H-M, Takashima M, Boundy-Mills K, Libkind D, Aoki K, Sugita T, Rokas A (2023). A genome-informed higher rank classification of the biotechnologically important fungal subphylum Saccharomycotina. Studies in Mycology 105: 1-22. doi: 10.3114/sim.2023.105.01 This study is dedicated to the memory of Cletus P. Kurtzman (1938-2017), a pioneer of yeast taxonomy.

3.
Acta Psychiatr Scand ; 139(1): 89-96, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30105761

RESUMO

OBJECTIVE: To investigate the frequency of childhood and adult attention deficit hyperactivity disorder (ADHD) symptoms in a cohort of patients with schizophrenia (SCZ). METHODS: A systematic review was conducted to evaluate existing evidence. Two self-report questionnaires were used to investigate adult ADHD and childhood ADHD symptoms in 126 patients with ICD-10 diagnoses of SCZ. RESULTS: Five studies were included in the systematic review, with the prevalence of childhood and adult ADHD in SCZ subjects ranging between 17-57% and 10-47% respectively. Within our cohort, 47% of patients reported positive screening for ADHD symptoms either in childhood or adulthood. 23% reported symptomatology consistent with both childhood and adult ADHD. CONCLUSIONS: We demonstrate a greater presence of ADHD symptomatology in SCZ compared to that reported for ADHD in the general population. Our findings highlight the importance of improved clinical assessment and treatment considerations in a subgroup of patients with SCZ.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Disfunção Cognitiva/epidemiologia , Esquizofrenia/epidemiologia , Adolescente , Adulto , Idoso , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Estudos de Coortes , Comorbidade , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Prevalência , Esquizofrenia/diagnóstico , Autorrelato/normas , Inquéritos e Questionários/normas , Adulto Jovem
4.
J Perinatol ; 35(8): 580-4, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25789817

RESUMO

OBJECTIVE: Racial differences in chronic maternal stress may contribute to disparities in pregnancy outcomes. The objective is to identify racial and ethnic differences in self-reported and biologic measures of stress between non-Hispanic black (NHB) and non-Hispanic white (NHW) pregnant women. STUDY DESIGN: NHB and NHW pregnant women were enrolled before 23 weeks of gestation in this prospective cohort study. Equal numbers of women were recruited with public vs private insurance in each racial group. Self-reported stress was measured and blood samples collected in the second and third trimesters were analyzed for serum Epstein-Barr virus antibody, C-reactive protein (CRP), corticotropin-releasing hormone (CRH) and adenocorticotropic hormone (ACTH). RESULTS: One hundred and twelve women were enrolled. NHW women reported more buffers against stress (P=0.04) and neighborhood satisfaction (P=0.02). NHB women reported more discrimination (P<0.001), food insecurity (P=0.04) and had significantly higher mean CRP levels and mean ACTH levels in the second and third trimesters. CONCLUSION: Significant differences in self-reported and biologic measures of chronic stress were identified between NHB and NHW pregnant women with similar economic characteristics. Future studies should investigate mechanisms underlying these differences and their relationship to pregnancy outcomes.


Assuntos
Biomarcadores/sangue , Complicações na Gravidez , Segundo Trimestre da Gravidez/sangue , Terceiro Trimestre da Gravidez/sangue , Gestantes/psicologia , Estresse Psicológico/etnologia , Hormônio Adrenocorticotrópico/sangue , Adulto , Negro ou Afro-Americano/etnologia , Anticorpos Antivirais/sangue , Proteína C-Reativa/análise , Hormônio Liberador da Corticotropina/sangue , Feminino , Humanos , Gravidez , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Autorrelato , Fatores Socioeconômicos , Estresse Psicológico/diagnóstico , Estados Unidos/etnologia , População Branca
5.
J Perinatol ; 35(4): 252-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25341198

RESUMO

OBJECTIVE: The study aim was to identify factors associated with vaginal birth after cesarean (VBAC) in high-risk women. STUDY DESIGN: This is a population-based retrospective cohort study of all births in Ohio during 2006 and 2007. High-risk patients were defined as singleton gestations in women with one previous cesarean who had ⩾1 of the following risk factors: body mass index (BMI)⩾30, hypertension, or diabetes. Multivariate logistic regression was utilized to estimate the relative influence of each factor on successful VBAC. RESULT: A total of 280 882 births were analyzed: of them, 79 084 (27.1%) were high-risk pregnancies and 8658 (10.9%) women had undergone one previous cesarean; 1433 (16.6%) underwent a trial of labor after cesarean (TOLAC). Of them, 974 (68.0%) had a successful VBAC, whereas 459 (32.0%) did not. Factors significantly associated with VBAC success were as follows: a prior vaginal delivery; pregnancy weight gain ⩽30 lbs; Caucasian race; and labor augmentation. CONCLUSION: High-risk women with one prior cesarean are unlikely to undergo a TOLAC, but have a high rate of VBAC.


Assuntos
Gravidez de Alto Risco/etnologia , Prova de Trabalho de Parto , Nascimento Vaginal Após Cesárea/estatística & dados numéricos , Aumento de Peso , População Branca , Adulto , Índice de Massa Corporal , Feminino , Humanos , Modelos Logísticos , Análise Multivariada , Ohio , Gravidez , Estudos Retrospectivos , Fatores de Risco
6.
Reprod Domest Anim ; 47 Suppl 6: 406-11, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23279551

RESUMO

Overpopulation of cats and dogs is a serious worldwide problem that demands novel, safe and cost-effective solutions. The objective of this study was to generate and characterize phage-peptide conjugates with gonadotropin-releasing hormone (GnRH) for potential use as an immunocontraceptive. A filamentous phage vector f5-8 with wild-type phage coat proteins was used as a carrier for construction of chemical conjugates with GnRH, a peptide that acts as a master reproductive hormone. In such conjugates, the phage body plays the role of a carrier protein, while multiple copies of GnRH peptide stimulate production of neutralizing anti-GnRH antibodies potentially leading to contraceptive effects. To generate the constructs, four different GnRH-based peptides were synthesized and conjugated to phage particles in a two-step procedure: (i) peptides were reacted with phage to form a conjugate using 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride chemistry (EDC) and (ii) the conjugates were separated from remaining free peptides by dialysis. Formation and specificity of phage-GnRH conjugates were confirmed by three independent methods: spectrophotometry, electron microscopy and ELISA. When the conjugates were tested for interaction with sera collected from cats and dogs immunized with GnRH-based vaccines in independent studies, strong specific ELISA signals were obtained, suggesting the potential use of the conjugates for cat and dog immunosterilization. The ability of the conjugates to stimulate production of anti-GnRH antibodies in vivo was evaluated in mice. While optimization of dose, immunization route and adjuvant still requires investigation, our preliminary results demonstrated the presence of anti-GnRH antibodies in sera of mice immunized with such conjugates. Fertility trials in cats and dogs will be needed to evaluate contraceptive potentials of the phage-GnRH peptide chemical conjugates.


Assuntos
Anticoncepção/veterinária , Hormônio Liberador de Gonadotropina/imunologia , Vacinas Anticoncepcionais/imunologia , Animais , Anticorpos/imunologia , Bacteriófagos , Gatos , Anticoncepção Imunológica/veterinária , Cães , Ensaio de Imunoadsorção Enzimática , Masculino , Camundongos
7.
Rheumatology (Oxford) ; 47(4): 488-90, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18285353

RESUMO

OBJECTIVE: The ischaemic complications of giant cell arteritis (GCA) such as blindness and stroke may result from luminal narrowing of the affected arteries. This study focuses on the association between the severity of intimal proliferation on temporal artery biopsy (TAB) histology and neuro-ophthalmic complications (NOCs) of GCA. METHOD: We identified 30 cases of biopsy-proven temporal arteritis. One histopathologist (blinded to the clinical details) evaluated the TAB specimens and categorized the degree of maximum stenosis due to intimal hyperplasia into four grades: grade 1 is <50% luminal occlusion due to intimal hyperplasia, grade 2 is 50-75%, grade 3 is >75% and grade 4 is complete luminal occlusion. A second histopathologist (also blinded to the clinical details) independently evaluated the TAB specimens using the same grading system. The NOCs in these patients were noted after a case record review. RESULTS: Of the 30 patients, 12 had NOC-10 with eye complications (complete visual loss, anterior ischaemic neuropathy, visual field defects), one patient had cerebral infarcts and one had both cerebral infarcts and vision loss. There was evidence for a statistically significant trend of NOC associated with higher intimal hyperplasia scores (P = 0.001). The scores of the histopathologists agreed for 23 (77%) patients and differed by 1 category for the remaining 7 (kappa-statistic 0.88). CONCLUSIONS: Our study suggests that the degree of intimal hyperplasia on TAB histology (routinely available to all hospital units) seems to be closely associated with NOCs of GCA. The study highlights the possible prognostic as well as diagnostic role of the biopsy. We feel that intimal hyperplasia noted in biopsy specimens may help us in the risk stratification of GCA patients and targeting of appropriate and novel therapies.


Assuntos
Arterite de Células Gigantes/complicações , Arterite de Células Gigantes/patologia , Artérias Temporais/patologia , Túnica Íntima/patologia , Transtornos da Visão/etiologia , Arteriopatias Oclusivas/etiologia , Arteriopatias Oclusivas/patologia , Biópsia , Infarto Cerebral/etiologia , Infarto Cerebral/patologia , Humanos , Hiperplasia , Índice de Gravidade de Doença , Transtornos da Visão/patologia
8.
J Plast Reconstr Aesthet Surg ; 60(11): 1260-2, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17950191

RESUMO

Solitary and multicentric myofibromas are rare fibrous tumours with marked predilection for infants and young children. Presentation is mainly before the age of 2 and lesions are often congenital. Behaviour is usually benign, but mortality has been described in lesions with visceral involvement. We report a unique case of congenital solitary cutaneous infantile myofibroma in a neonate associated with self-limiting thrombocytopaenia. It is important to distinguish accurately these lesions from benign vascular tumours like haemangiomas, locally aggressive vascular tumours like Kaposiform haemangioendotheliomas, which are often associated with Kasabach-Merritt phenomenon and also with malignant soft tissue tumours of infancy.


Assuntos
Doenças em Gêmeos/diagnóstico , Miofibroma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Trombocitopenia/diagnóstico , Humanos , Lactente , Masculino , Regressão Neoplásica Espontânea , Resultado do Tratamento
10.
Br J Plast Surg ; 58(3): 348-52, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15780229

RESUMO

The differential diagnosis between juvenile haemangiomas, vascular malformations, pyogenic granulomas and normally proliferative endothelium (granulation tissue) on the basis of histology alone is sometimes difficult. This is important because haemangiomas, are self-limiting and vascular malformations are not. We report our experience of using the immunohistochemical marker GLUT-1 to distinguish haemangiomas from vascular malformations following the initial report by North and Colleagues (1998). We studied a total of 50 specimens from patients with vascular anomalies, and found that GLUT-1 reactivity was positive in 18 out of 19 juvenile haemangiomas, negative in two out of two noninvoluting congenital haemangiomas (NICH) and negative in 29 out of 29 vascular malformations, that included capillary malformations, lymphatic malformations, venous malformations and arteriovenous malformations (95% sensitivity, 100% specificity). Pyogenic granulomas (n = 4) and granulation tissue samples (n = 4) were used as negative controls. Placenta tissue was used as positive control. GLUT-1 accurately distinguishes haemangiomas from vascular malformations, and as a result from this work, we use this technique in routine histopathological differentiation of vascular anomalies.


Assuntos
Biomarcadores Tumorais/metabolismo , Anormalidades Cardiovasculares/diagnóstico , Hemangioma/diagnóstico , Proteínas de Transporte de Monossacarídeos/metabolismo , Neoplasias Cutâneas/diagnóstico , Diagnóstico Diferencial , Transportador de Glucose Tipo 1 , Humanos , Proteínas de Neoplasias/metabolismo
11.
Br J Plast Surg ; 56(1): 50-2, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12706152

RESUMO

We present a case of squamous cell carcinoma arising in a naevus sebaceous of Jadassohn (NSJ) in a 15-year-old girl. Both these events are rare, and this is the first reported case of a squamous cell carcinoma developing in NSJ in a child. The previous literature on sebaceous naevi and malignancies arising thereof is reviewed and discussed. Early excision is recommended in any cases of nodular change in sebaceous naevi in all age groups.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Neoplasias de Cabeça e Pescoço/cirurgia , Nevo/cirurgia , Couro Cabeludo , Neoplasias Cutâneas/cirurgia , Adolescente , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Nevo/complicações , Nevo/patologia , Neoplasias das Glândulas Sebáceas/complicações , Neoplasias das Glândulas Sebáceas/patologia , Neoplasias das Glândulas Sebáceas/cirurgia , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/patologia , Resultado do Tratamento
14.
J Laryngol Otol ; 116(4): 296-8, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11945194

RESUMO

A 71-year-old lady underwent successful excision of a haemangioma of the frontal sinus, via an osteoplastic flap approach. Haemangioma of the paranasal sinuses is an extreme rarity. A case is presented and the literature reviewed.


Assuntos
Seio Frontal , Hemangioma/patologia , Neoplasias dos Seios Paranasais/patologia , Idoso , Feminino , Hemangioma/cirurgia , Humanos , Neoplasias dos Seios Paranasais/cirurgia , Tomografia Computadorizada por Raios X
15.
Differentiation ; 67(4-5): 117-27, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11683495

RESUMO

Formation of two spherical Balbiani bodies along the long axis of previtellogenic oocytes in Acheta domesticus was demonstrated by differential interference microscopy. The structures form adjacent to and on opposite sides of the germinal vesicle, the anterior body first. Each migrates to the nearest pole of the elongating oocyte and retains its spherical structure until occluded from view by accumulating yolk. In situ hybridization, immunocytochemistry, and confocal immunofluorescent microscopy showed Balbiani body components to include y-tubulin, alpha-tubulin, EF1alpha, and several RNAs homologous to localized Xenopus RNAs implicated in embryonic axis formation or germ cell determination. The latter include Xcat2, Xwnt11, Xlsirt, and Xpat. Balbiani body ultrastructure includes a dense cloud of tubular mitochondria, rough ER, Golgi-like membrane aggregates, and microtubules. The results suggest that molecules and mechanisms specifying early determinative events for embryogenesis in vertebrates and insects are highly conserved and that Balbiani bodies may have a role in establishing developmental asymmetry in the cricket.


Assuntos
Gryllidae/citologia , Gryllidae/genética , Oócitos/crescimento & desenvolvimento , Oócitos/ultraestrutura , RNA/metabolismo , Animais , Hibridização In Situ , Microscopia Eletrônica , Oócitos/citologia , Oócitos/metabolismo , Organelas/metabolismo , Organelas/ultraestrutura , RNA/genética , Sondas RNA/genética , RNA Antissenso/genética , Coloração e Rotulagem , Xenopus/genética
16.
Br J Plast Surg ; 54(4): 367-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11355999

RESUMO

Lymphatic malformations are a type of vascular anomaly. They are uncommon and can present in various ways. Associated hypertrophy of the soft tissue and bone have been described in association with deep lymphatic connections, but late-onset localised fat hypertrophy in the absence of deep connections has not been previously described. We present a case of cutaneous lymphatic malformation of the thigh and buttock with secondary fat hypertrophy. The lesion had been present since childhood but enlarged rapidly during adolescence. MRI excluded deep connections and lipoma. Liposuction was used to debulk the area with a satisfactory result.


Assuntos
Tecido Adiposo/patologia , Sistema Linfático/anormalidades , Adulto , Feminino , Humanos , Hipertrofia/diagnóstico , Hipertrofia/etiologia , Hipertrofia/cirurgia , Perna (Membro) , Lipectomia/métodos , Imageamento por Ressonância Magnética/métodos , Resultado do Tratamento
17.
Nat Rev Genet ; 2(5): 333-41, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11331899

RESUMO

Thirty years after Susumu Ohno proposed that vertebrate genomes are degenerate polyploids, the extent to which genome duplication contributed to the evolution of the vertebrate genome, if at all, is still uncertain. Sequence-level studies on model organisms whose genomes show clearer evidence of ancient polyploidy are invaluable because they indicate what the evolutionary products of genome duplication can look like. The greatest mystery is the molecular basis of diploidization, the evolutionary process by which a polyploid genome turns into a diploid one.


Assuntos
Diploide , Evolução Molecular , Genes de Plantas/genética , Genoma de Planta , Plantas/genética , Poliploidia , Saccharomyces cerevisiae/genética , Animais , Duplicação Gênica , Frequência do Gene , Variação Genética , Humanos
18.
Plant Cell ; 13(3): 645-58, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11251102

RESUMO

We used DNA sequencing and gel blot surveys to assess the integrity of the chloroplast gene infA, which codes for translation initiation factor 1, in >300 diverse angiosperms. Whereas most angiosperms appear to contain an intact chloroplast infA gene, the gene has repeatedly become defunct in approximately 24 separate lineages of angiosperms, including almost all rosid species. In four species in which chloroplast infA is defunct, transferred and expressed copies of the gene were found in the nucleus, complete with putative chloroplast transit peptide sequences. The transit peptide sequences of the nuclear infA genes from soybean and Arabidopsis were shown to be functional by their ability to target green fluorescent protein to chloroplasts in vivo. Phylogenetic analysis of infA sequences and assessment of transit peptide homology indicate that the four nuclear infA genes are probably derived from four independent gene transfers from chloroplast to nuclear DNA during angiosperm evolution. Considering this and the many separate losses of infA from chloroplast DNA, the gene has probably been transferred many more times, making infA by far the most mobile chloroplast gene known in plants.


Assuntos
DNA de Cloroplastos/genética , Magnoliopsida/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Arabidopsis/genética , Fusão Gênica Artificial , Núcleo Celular/genética , Sondas de DNA , Elementos de DNA Transponíveis/genética , Evolução Molecular , Proteínas de Fluorescência Verde , Indicadores e Reagentes , Íntrons , Proteínas Luminescentes , Solanum lycopersicum/genética , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/genética , Rosales/genética , Análise de Sequência de DNA , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Glycine max/genética
19.
Anal Biochem ; 291(1): 118-23, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11262164

RESUMO

We developed a method to measure hemoglobin synthesis rate (SynHb) in humans, assuming that free glycine in the red blood cell (RBC) represents free glycine in bone marrow for hemoglobin synthesis. The present rat study examines this assumption of the method and quantifies SynHb in rats. Sprague-Dawley rats (n = 9) were studied, [2-(13)C]glycine was intravenously infused over 24 h (2.5 mg kg(-1) h(-1)), blood was drawn for glycine and heme isolation, and bone marrow was harvested for glycine isolation. Isotopic enrichments of glycine and heme were measured, fractional hemoglobin synthesis rate (fSynHb% day(-1)) was calculated, and from this a value for SynHb (mg g(-1) day(-1)) was derived. Mean body weight was 446 +/- 10 g (mean +/- SE) and hemoglobin concentration was 14 +/- 0.5 g dl(-1). At 24 h, the mean isotopic enrichment, atom percentage excess (APE), of the RBC free glycine (1.56 +/- 0.18 APE) was similar to the bone marrow (1.68 +/- 0.15 APE). The rate of incorporation of (13)C into heme increased over time from 0.0004 APE/h between 6 and 12 h, to 0.0014 APE/h between 12 and 18 h, and 0.0024 APE/h between 18 and 24 h. Consequently, fSynHb (1.19 +/- 0.32, 2.92 +/- 0.66, and 4.22 +/- 0.56% day(-1), respectively) and SynHb (0.11 +/- 0.03, 0.28 +/- 0.05, and 0.42 +/- 0.05 mg g(-1) day(-1), respectively) showed similar patterns over the 24-h study period. We conclude that (1) enrichment of free glycine in the circulating RBC approximates enrichment of bone marrow free glycine for heme formation and (2) this pattern of hemoglobin synthesis rate is reflecting the characteristic release and gradual maturation of reticulocytes in the circulation.


Assuntos
Medula Óssea/metabolismo , Glicina/análise , Hemoglobinas/análise , Hemoglobinas/biossíntese , Marcação por Isótopo/métodos , Animais , Medula Óssea/anatomia & histologia , Eritrócitos/metabolismo , Glicina/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
20.
Proc Natl Acad Sci U S A ; 97(26): 14433-7, 2000 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-11087826

RESUMO

Gene order evolution in two eukaryotes was studied by comparing the Saccharomyces cerevisiae genome sequence to extensive new data from whole-genome shotgun and cosmid sequencing of Candida albicans. Gene order is substantially different between these two yeasts, with only 9% of gene pairs that are adjacent in one species being conserved as adjacent in the other. Inversion of small segments of DNA, less than 10 genes long, has been a major cause of rearrangement, which means that even where a pair of genes has been conserved as adjacent, the transcriptional orientations of the two genes relative to one another are often different. We estimate that about 1,100 single-gene inversions have occurred since the divergence between these species. Other genes that are adjacent in one species are in the same neighborhood in the other, but their precise arrangement has been disrupted, probably by multiple successive multigene inversions. We estimate that gene adjacencies have been broken as frequently by local rearrangements as by chromosomal translocations or long-distance transpositions. A bias toward small inversions has been suggested by other studies on animals and plants and may be general among eukaryotes.


Assuntos
Candida albicans/genética , Inversão Cromossômica , Evolução Molecular , Genes Fúngicos , Saccharomyces cerevisiae/genética , Cromossomos Fúngicos , Rearranjo Gênico , Genoma Fúngico
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