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1.
Artigo em Inglês | MEDLINE | ID: mdl-37500829

RESUMO

OBJECTIVES: To determine if SARS-CoV-2 disproportionately impacted infants born to racial and ethnic minorities and if virus exposure led to decreased access to care. METHODS: This study was an observational case-control study, between March 2020 and March 2022 in Portland, Maine. Forty-seven cases and 47 controls were enrolled. Cases were infants born to mothers diagnosed with SARS-CoV-2 at delivery, and controls were infants matched by date of birth, born to SARS-CoV-2 negative women. Demographic data, maternal clinical data, infant outcomes, and infant discharge plans were compared using Chi squared or Fisher Exact tests. Logistic regression was used to examine the impact of race on neonatal SARS-CoV-2 exposure. RESULTS: Infants exposed to SARS-CoV-2 were more likely Black or Hispanic than White and Non-Hispanic early in the pandemic, with reversal during the second year. SARS-CoV-2-exposed infants experienced delays in routine newborn outpatient care, although delay improved over the pandemic. CONCLUSION: Infants exposed to SARS-CoV-2 were initially more likely to be infants of color. During this time, infants exposed to SARS-CoV-2 were also experiencing significant delays in newborn care.

2.
J Trop Pediatr ; 69(1)2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36647897

RESUMO

Leishmaniasis has varying clinical manifestations and treatment regimens, dependent on species and host. Old world leishmaniasis, found primarily in Africa and Asia, may be associated with visceral disease, while new world disease, primarily in Latin America, may be associated with mucocutaneous disease. We present a case series of pediatric African patients with New World cutaneous leishmaniasis. Data extraction was performed via chart review, of children with cutaneous leishmaniasis presenting to the pediatric infectious diseases clinic in Portland, ME. Biopsy specimens were sent to the federal center for disease control (CDC) for identification via polymerase chain reaction (PCR) and culture. Five cases of cutaneous leishmaniasis were diagnosed in pediatric patients (ages 1-17 years) in Maine during the study period. Leishmaniasis was not initially suspected; thus, time to diagnosis was 1-4 months, Two patients were diagnosed with Leishmania panamensis, one with Leishmania brasiliensis, one with Leishmania sp. and one with mixed infection (L. panamensis and Leishmania mexicana). One patient was managed with surgical excision only, one was observed off therapy, and three were treated with ketoconazole. This case series highlights the importance of a high index of suspicion in migrant patients. Detailed travel history and epidemiologic knowledge is essential to diagnosis, as patients may present with forms of illness not congruent with their country of origin.


Assuntos
Leishmania , Leishmaniose Cutânea , Humanos , Criança , Lactente , Pré-Escolar , Adolescente , Maine/epidemiologia , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/epidemiologia , Reação em Cadeia da Polimerase , África
3.
Plants (Basel) ; 10(8)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34451639

RESUMO

The central floral development gene LEAFY (LFY), whose mutation leads to striking changes in flowering and often sterility, is commonly expressed in non-floral structures; however, its role in vegetative development is poorly understood. Sterility associated with suppression of LFY expression is an attractive means for mitigating gene flow by both seeds and pollen in vegetatively propagated forest trees, but the consequences of its suppression for tree form and wood production are unclear. To study the vegetative effects of RNAi suppression of LFY, we created a randomized, multiple-year field study with 30-40 trees (ramets) in each of two sterile gene insertion events, three transgenic control events, and a wild-type control population. We found that floral knock-down phenotypes were stable across years and propagation cycles, but that several leaf morphology and productivity traits were statistically and often substantially different in sterile vs. normal flowering RNAi-LFY trees. Though trees with suppressed LEAFY expression looked visibly normal, they appear to have reduced growth and altered leaf traits. LFY appears to have a significant role in vegetative meristem development, and evaluation of vegetative impacts from LFY suppression would be prudent prior to large-scale use for genetic containment.

4.
Hortic Res ; 8(1): 167, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34333535

RESUMO

The spread of transgenes and exotic germplasm from planted crops into wild or feral species is a difficult problem for public and regulatory acceptance of genetically engineered plants, particularly for wind-pollinated trees such as poplar. We report that overexpression of a poplar homolog of the floral repressor SHORT VEGETATIVE PHASE-LIKE (SVL), a homolog of the Arabidopsis MADS-box repressor SHORT VEGETATIVE PHASE (SVP), delayed the onset of flowering several years in three genotypes of field-grown transgenic poplars. Higher expression of SVL correlated with a delay in flowering onset and lower floral abundance, and did not cause morphologically obvious or statistically significant effects on leaf characteristics, tree form, or stem volume. Overexpression effects on reproductive and vegetative phenology in spring was modest and genotype-specific. Our results suggest that use of SVL and related floral repressors can be useful tools to enable a high level of containment for vegetatively propagated short-rotation woody energy or pulp crops.

8.
Cell Host Microbe ; 18(3): 307-19, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26299432

RESUMO

Bacterial lineages that chronically infect cystic fibrosis (CF) patients genetically diversify during infection. However, the mechanisms driving diversification are unknown. By dissecting ten CF lung pairs and studying ∼12,000 regional isolates, we were able to investigate whether clonally related Pseudomonas aeruginosa inhabiting different lung regions evolve independently and differ functionally. Phylogenetic analysis of genome sequences showed that regional isolation of P. aeruginosa drives divergent evolution. We investigated the consequences of regional evolution by studying isolates from mildly and severely diseased lung regions and found evolved differences in bacterial nutritional requirements, host defense and antibiotic resistance, and virulence due to hyperactivity of the type 3 secretion system. These findings suggest that bacterial intermixing is limited in CF lungs and that regional selective pressures may markedly differ. The findings also may explain how specialized bacterial variants arise during infection and raise the possibility that pathogen diversification occurs in other chronic infections characterized by spatially heterogeneous conditions.


Assuntos
Fibrose Cística/complicações , Variação Genética , Pulmão/microbiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , Humanos , Dados de Sequência Molecular , Pseudomonas aeruginosa/isolamento & purificação , Análise de Sequência de DNA
9.
Proc Natl Acad Sci U S A ; 109(34): 13769-74, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22872870

RESUMO

Recent work using culture-independent methods suggests that the lungs of cystic fibrosis (CF) patients harbor a vast array of bacteria not conventionally implicated in CF lung disease. However, sampling lung secretions in living subjects requires that expectorated specimens or collection devices pass through the oropharynx. Thus, contamination could confound results. Here, we compared culture-independent analyses of throat and sputum specimens to samples directly obtained from the lungs at the time of transplantation. We found that CF lungs with advanced disease contained relatively homogenous populations of typical CF pathogens. In contrast, upper-airway specimens from the same subjects contained higher levels of microbial diversity and organisms not typically considered CF pathogens. Furthermore, sputum exhibited day-to-day variation in the abundance of nontypical organisms, even in the absence of clinical changes. These findings suggest that oropharyngeal contamination could limit the accuracy of DNA-based measurements on upper-airway specimens. This work highlights the importance of sampling procedures for microbiome studies and suggests that methods that account for contamination are needed when DNA-based methods are used on clinical specimens.


Assuntos
Fibrose Cística/genética , Pulmão/microbiologia , Metagenoma/fisiologia , Escarro/microbiologia , Traqueia/microbiologia , Antibacterianos/farmacologia , Bactérias/genética , Humanos , Pulmão/metabolismo , Pneumologia/métodos , RNA Ribossômico 16S/metabolismo , Análise de Sequência de DNA , Especificidade da Espécie , Manejo de Espécimes
10.
J Am Chem Soc ; 131(14): 5153-62, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19309137

RESUMO

Considerable effort has focused on the development of selective protein farnesyl transferase (FTase) and protein geranylgeranyl transferase (GGTase) inhibitors as cancer chemotherapeutics. Here, we report a new strategy for anticancer therapeutic agents involving inhibition of farnesyl diphosphate synthase (FPPS) and geranylgeranyl diphosphate synthase (GGPPS), the two enzymes upstream of FTase and GGTase, by lipophilic bisphosphonates. Due to dual site targeting and decreased polarity, the compounds have activities far greater than do current bisphosphonate drugs in inhibiting tumor cell growth and invasiveness, both in vitro and in vivo. We explore how these compounds inhibit cell growth and how cell activity can be predicted based on enzyme inhibition data, and using X-ray diffraction, solid state NMR, and isothermal titration calorimetry, we show how these compounds bind to FPPS and/or GGPPS.


Assuntos
Difosfonatos/química , Difosfonatos/farmacologia , Farnesiltranstransferase/antagonistas & inibidores , Farnesiltranstransferase/metabolismo , Geraniltranstransferase/antagonistas & inibidores , Geraniltranstransferase/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Humanos , Lipídeos/química , Camundongos , Camundongos Nus , Invasividade Neoplásica , Ressonância Magnética Nuclear Biomolecular , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/metabolismo , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Proteínas de Saccharomyces cerevisiae/metabolismo , Trypanosoma brucei brucei/enzimologia
11.
Chem Biol ; 13(9): 985-92, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16984888

RESUMO

Human gammadelta T cells containing the Vgamma2Vdelta2 (Vgamma9Vdelta2) T cell receptor are stimulated by a broad variety of small, phosphorus-containing antigenic molecules called phosphoantigens. The structures of several species present in both Mycobacteria (TUBags1-4) and in Escherichia coli have been reported to contain a formyl-alkyl diphosphate core. Here we report the synthesis of the lead member of the series, 3-formyl-1-butyl diphosphate. This compound has low activity for gammadelta T cell stimulation, unlike its highly active isomer (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate, necessitating a revision of the structure of TUBag1. Likewise, the structure of the species identified as the pentyl analog (TUBag 2) is revised to 6-phosphogluconate. These results indicate that neither TUBag1 nor the m/e 275 species proposed for TUBag2 are 3-formyl-1-alkyl diphosphates, leading to the conclusion that none of the natural phosphoantigens (TUBags1-4) possess the structures reported previously.


Assuntos
Antígenos de Bactérias/química , Organofosfatos/química , Organofosfatos/imunologia , Compostos Organofosforados/química , Compostos Organofosforados/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Subpopulações de Linfócitos T/imunologia , Antígenos de Bactérias/imunologia , Humanos , Ativação Linfocitária , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Mycobacterium/imunologia , Compostos Organofosforados/síntese química , Vacinas Sintéticas/imunologia
12.
J Am Chem Soc ; 128(11): 3524-5, 2006 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-16536518

RESUMO

We report the results of an ITC (isothermal titration calorimetry) investigation of the binding of six bisphosphonates to the enzyme farnesyl diphosphate synthase (FPPS; EC 2.5.1.10) from Trypanosoma brucei. The bisphosphonates investigated were zoledronate, risedronate, ibandronate, pamidronate, 2-phenyl-1-hydroxyethane-1,1-bisphosphonate, and 1-(2,2-bisphosphonoethyl)-3-iodo pyridinium. At pH = 7.4, both risedronate and the phenylethane bisphosphonate bind in an enthalpy-driven manner (DeltaH approximately -9 to 10 kcal mol-1), but the other four bisphosphonates bind in an entropy-driven manner (DeltaS varying from 31.2 to 55.1 cal K-1 mol-1). However, at pH = 8.5, zoledronate binding switches from entropy to enthalpy-driven. The DeltaG results are highly correlated with FPPS inhibition results obtained using a radiochemical assay (R2 = 0.85, N = 11, P < 0.001). The DeltaH and DeltaS results are interpreted in terms of a model in which bisphosphonates with charged side chains have positive DeltaH values, due to the enthalpic cost of desolvation (due to strong ion-dipole interactions) and, likewise, a positive DeltaS, due to an increase in water entropy (both ligand and protein associated) on ligand binding to FPPS: the hydrophobic effect. For the neutral side chains (risedronate at pH 7.4, 8.5 and zoledronate at pH 8.5, as well as the phenylethane bisphosphonate), binding is overwhelmingly enthalpy-driven, with the enhanced activity of the basic side chain containing species being attributable to their becoming protonated in the active site. Given the large size of the bisphosphonate market and the potential importance of the development of these compounds for cancer immunotherapy and anti-parasitic chemotherapy, these results are of broad general interest in the context of the development of new, potent, and selective FPPS inhibitors.


Assuntos
Difosfonatos/química , Geraniltranstransferase/química , Animais , Difosfonatos/metabolismo , Ácido Etidrônico/análogos & derivados , Ácido Etidrônico/química , Ácido Etidrônico/metabolismo , Geraniltranstransferase/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Ácido Ibandrônico , Cinética , Ácido Risedrônico , Eletricidade Estática , Termodinâmica , Trypanosoma brucei brucei/enzimologia
13.
J Sex Med ; 3(2): 296-302, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16490023

RESUMO

AIM: To investigate possible causes and treatment of persistent sexual arousal syndrome, which was exacerbated by sleep onset, in a postmenopausal subject. METHODS: A clinical examination and interviews with the patient to obtain her case history and follow-up of the effects of drug treatments. Pretreatment laboratory investigations monitored vaginal blood flow by photoplethysmography and heated electrode. Routine blood chemistry and endocrine assessments were undertaken. Magnetic resonance imaging (MRI) scans of brain, pelvis, and spinal cord and genito-sensory neural analysis of clitoral and vaginal areas were performed. A selective internal iliac artery arteriogram was utilized to check the normality of the pelvic blood supply. RESULTS: Genitalia appeared normal and uncongested. No structural abnormalities were observed in the MRI scans. Hormonal levels and blood chemistry were commensurate with the subject's postmenopausal status. Basal vaginal blood flow (heat electrode) was within the range of normal premenopausal women and showed (photoplethysmography) normal vasomotion. On becoming drowsy and falling lightly asleep in the laboratory the vaginal pulse amplitude (VPA) increased by 95% of the basal value and the low-amplitude VPAs were replaced by high-amplitude VPAs--all evidence of increased vaginal blood flow and congestion and confirming the subject's complaint of persistent sexual arousal during sleep. A simple cognitive task of repeatedly subtracting 7 from 500 out aloud did not hasten the reversion to the basal level. There was no evidence of malfunction of the brain, spinal cord, or pelvic area by MRI but genito-sensory analysis of the clitoral and vaginal area showed evidence of reduced sensory function. CONCLUSIONS: Of the treatments tried only risperidone has been effective allowing the subject to sleep throughout the night without disturbance and according to the subject has significantly reduced the aggravation of the arousal during the day.


Assuntos
Nível de Alerta , Pós-Menopausa , Disfunções Sexuais Fisiológicas/complicações , Transtornos Intrínsecos do Sono/etiologia , Nível de Alerta/efeitos dos fármacos , Feminino , Humanos , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Risperidona/administração & dosagem , Disfunções Sexuais Fisiológicas/psicologia , Transtornos Intrínsecos do Sono/tratamento farmacológico , Vagina/irrigação sanguínea
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