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1.
Genetics ; 225(3)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37708366

RESUMO

In addition to inducing nonautonomous specification of cell fate in both Drosophila and vertebrates, the Hedgehog pathway guides cell migration in a variety of different tissues. Although its role in axon guidance in the vertebrate nervous system is widely recognized, its role in guiding the migratory path of primordial germ cells (PGCs) from the outside surface of the Drosophila embryo through the midgut and mesoderm to the SGPs (somatic gonadal precursors) has been controversial. Here we present new experiments demonstrating (1) that Hh produced by mesodermal cells guides PGC migration, (2) that HMG CoenzymeA reductase (Hmgcr) potentiates guidance signals emanating from the SGPs, functioning upstream of hh and of 2 Hh pathway genes important for Hh-containing cytonemes, and (3) that factors required in Hh receiving cells in other contexts function in PGCs to help direct migration toward the SGPs. We also compare the data reported by 4 different laboratories that have studied the role of the Hh pathway in guiding PGC migration.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Movimento Celular/genética , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Células Germinativas/metabolismo , Gônadas/metabolismo , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo
2.
Chirality ; 35(11): 889-898, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37345319

RESUMO

A novel, simple, specific, rapid, enantioselective normal phase chiral high-performance liquid chromatographic method with amylose-based Chiral Pak IG-3(250 × 4.6 mM) 3.0 µM column was developed and validated for separation and quantification of isomers and enantiomer of Valbenazine. The mobile phase composed of n-Heptane, isopropyl alcohol, dichloromethane, ethanol, and diethylamine in the ratio of 70:10:15:5:0.1 (V/V/V/VV) with a gradient flow rate was applied. The injection volume was 10 µl, and detection was carried out using a photodiode array detector at 282 nM. The column compartment was set at 35°C. The resolution between the enantiomer and isomers was found to be more than 2.0. The method was linear over the concentration range of limit of quantitation to 250% for isomers and enantiomers. The method was found to be robust with column temperature. The proposed chiral method is applicable for the determination of isomers and enantiomer of Valibenazine and was successfully used in the quality control of bulk drug manufacturing and pharmaceuticals.

3.
Biomed Chromatogr ; 37(8): e5646, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37070159

RESUMO

The newly synthesized lead molecule methyl-ester-toluene-sulfonamide is the combined derivative of sulfonamide-anthranilate. It was estimated by gradient elution using 0.1% triethylamine in water with pH 2.0 as mobile phase A and the mixture of acetonitrile and tetrahydrofuran in the ratio of 975:25 (v/v) as mobile phase B at a flow rate of 0.8 ml/min and 210 nm wavelength on an Agilent 1260 infinity series HPLC system equipped with a diode array detector. The column used was ACE 3 C18-PFP (250 × 4.6 mm, 3 µm i.d.) operating at 40°C. The gradient program was time (min)/% B: 0.0/50, 3.0/50, 15.0/70, 25.0/90, 30.0/90, 31/50, and 38/50. The method is simple, accurate, rapid, and selective. The method was linear with a concentration range of 1.6-240 µg/ml. The accuracy data obtained were 98.5-100.5%. The method validation data and quality by design-based robustness study results indicate that the developed method is robust and fit for routine use in the quality control laboratory. Therefore, the ready availability of the method can be useful in pharmaceutical new drug development.


Assuntos
Anti-Infecciosos , Cromatografia Líquida de Alta Pressão/métodos , Tolueno
4.
Elife ; 122023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36598809

RESUMO

In Drosophila melanogaster embryos, somatic versus germline identity is the first cell fate decision. Zygotic genome activation (ZGA) orchestrates regionalized gene expression, imparting specific identity on somatic cells. ZGA begins with a minor wave that commences at nuclear cycle (NC)8 under the guidance of chromatin accessibility factors (Zelda, CLAMP, GAF), followed by the major wave during NC14. By contrast, primordial germ cell (PGC) specification requires maternally deposited and posteriorly anchored germline determinants. This is accomplished by a centrosome coordinated release and sequestration of germ plasm during the precocious cellularization of PGCs in NC10. Here, we report a novel requirement for Zelda and CLAMP during the establishment of the germline/soma distinction. When their activity is compromised, PGC determinants are not properly sequestered, and specification is disrupted. Conversely, the spreading of PGC determinants from the posterior pole adversely influences transcription in the neighboring somatic nuclei. These reciprocal aberrations can be correlated with defects in centrosome duplication/separation that are known to induce inappropriate transmission of the germ plasm. Interestingly, consistent with the ability of bone morphogenetic protein (BMP) signaling to influence specification of embryonic PGCs, reduction in the transcript levels of a BMP family ligand, decapentaplegic (dpp), is exacerbated at the posterior pole.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Zigoto/metabolismo , Células Germinativas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento
5.
J Neurosurg Case Lessons ; 3(5)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36130563

RESUMO

BACKGROUND: Reports of ruptured neonatal aneurysms are rare in neurosurgical literature. Pediatric aneurysms differ from adult aneurysms, notably in morphology, size, number, and risk of rerupture. Many authors report experience with clipping, citing durability and decreased use of radiation as benefits over endovascular intervention. Few authors report extracranial-to-intracranial bypass because small pediatric vessels make this option challenging. The authors discussed a case of a newborn with multiple ruptured aneurysms, one of the youngest reported cases involving extracranial-intracranial bypass. OBSERVATIONS: A 3-week-old baby presented with hemorrhage from multiple complex middle cerebral artery (MCA) aneurysms. Because of young age, endovascular intervention was not possible; therefore, the patient received craniotomy. Upon exploration, clip reconstruction was impossible; the vessel was trapped, and superficial temporal artery (STA)-MCA bypass was performed. The recipient vessel diameter was 0.3 mm. The postoperative course was complicated by seizures as well as symptomatic vasospasm, which was treated with intraarterial verapamil and ventriculostomy. At last follow-up, the patient was developing normally and was ambulatory with minimal deficit. LESSONS: This case, one of the youngest patients reported, highlighted details of pediatric aneurysm management, such as propensity for multiple/fusiform aneurysms and high risk of re-hemorrhage, with significant mortality. The authors recommended aggressive, early intervention in pediatric aneurysms at centers with surgeons familiar with both endovascular intervention and cerebral bypass.

6.
BMJ Case Rep ; 15(4)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35487636

RESUMO

Status epilepticus (SE) is a life-threatening medical emergency which is frequently encountered in the critical care setting and can be refractory to treatment. Refractory status epilepticus (RSE) is defined as SE that has failed to respond to adequately used first-line and second-line antiepileptic medications. Super refractory status epilepticus is defined as SE that persists for 24 hours or more after the use of an anaesthetic agent or recurs after its withdrawal.If SE persists beyond a period of 7 days it is referred to as prolonged, refractory status epilepticus (PRSE). There are limited data guiding treatment of RSE in the paediatric population.Lacosamide (LCM) is licensed as an adjunctive treatment for partial-onset seizures. Evidence for the efficacy of LCM in paediatric SE is scarce. This case report may suggest a synergistic effect of LCM on slow-activation sodium channels in conjunction with medications such as phenytoin that causes fast inactivation of sodium channels. The dual fast and slow inactivation of sodium channels may enhance the effectiveness in treatment of RSE. This is the first case report of PRSE in an infant, successfully treated with LCM. A brief review of literature is also a part of this report.


Assuntos
Anticonvulsivantes , Estado Epiléptico , Anticonvulsivantes/uso terapêutico , Epilepsia Parcial Contínua/tratamento farmacológico , Humanos , Lactente , Lacosamida/uso terapêutico , Convulsões/tratamento farmacológico , Estado Epiléptico/tratamento farmacológico
7.
J Pediatr Surg ; 57(12): 1018-1025, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35396086

RESUMO

OBJECTIVES: The burden of pediatric trauma and emergency, including pediatric surgical emergencies in low middle income countries (LMIC) is high. The goal of Pediatric Acute Surgical Support (PASS) course is to prepare caregivers in LMIC for the acute management of life-threatening pediatric surgical emergencies. We aim to show the feasibility of its initial deployment. METHODS: PASS was developed in 2016 with LMIC faculty from a teaching children hospital CH. The course contents consisted of a mix of didactic materials for serious general neonatal and pediatric surgery modified PALS/ATLS, in-person multidisciplinary team-based skill stations, interactive clinical scenarios and simulated trauma cases. The course was subsequently revised and delivered to 92 learners in four classes of 2.5-days sessions at two CHs between 2017 and 2019. Learners' demographics, written exams, team-based case performance, and post-course survey data were prospectively collected and retrospectively analyzed. RESULTS: Physician (60%) and nurse learners (40%) from pediatric critical care (36%), surgery (23%), emergency medicine (20%) and anesthesiology (9%) had 3.6 +/- 3.6 years of clinical practice; pre- and post-course written exam score of 55.4+/-15.5% vs 71.6+/-12.8%, team-based trauma scenario management 22.6 ± 7.8% vs 54.7 ± 16.6% and team-based dynamic scores 17+/- 10% vs 53.3+/- 15.5%, respectively (p<0.0001). Self-reported satisfaction scores were ≥ 95% for course method, level of difficulty, clinical applicability, and quality of instructors. CONCLUSION: PASS is well-received by LMIC learners, with short-term improvement in knowledge-, team-based management of acute pediatric surgery emergencies; and has the potential to be a model of horizontal capacity building for pediatric surgery in LMIC. LEVEL OF EVIDENCE: II.


Assuntos
Medicina de Emergência , Especialidades Cirúrgicas , Humanos , Criança , Recém-Nascido , Emergências , Países em Desenvolvimento , Estudos Retrospectivos , Medicina de Emergência/educação
8.
BMJ Case Rep ; 15(4)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35410945

RESUMO

We describe a girl in middle childhood with newly diagnosed Crohn's disease, who presented with seizures and altered mental status. MRI showed an abnormal vascular signal at the basilar artery, but no evidence of acute ischaemia. Her weakness worsened over the next 8 hours to dense quadriplegia. CT angiography of the brain, approximately 24 hours after the initial onset of symptoms, identified an acute basilar artery occlusion with infarction. She received endovascular thromboembolectomy emergently. She showed significant improvement over 8-month period from quadriplegia to walking unassisted. This case highlights the importance of recognising stroke in patients with inflammatory bowel disease and the need for emergent radiological assessment and potential intervention.


Assuntos
Arteriopatias Oclusivas , Doença de Crohn , Acidente Vascular Cerebral , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/etiologia , Arteriopatias Oclusivas/cirurgia , Artéria Basilar , Criança , Doença de Crohn/complicações , Feminino , Humanos , Quadriplegia
9.
Elife ; 112022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35311642

RESUMO

We recently identified a missense mutation in Nucleoporin107 (Nup107; D447N) underlying XX-ovarian-dysgenesis, a rare disorder characterized by underdeveloped and dysfunctional ovaries. Modeling of the human mutation in Drosophila or specific knockdown of Nup107 in the gonadal soma resulted in ovarian-dysgenesis-like phenotypes. Transcriptomic analysis identified the somatic sex-determination gene doublesex (dsx) as a target of Nup107. Establishing Dsx as a primary relevant target of Nup107, either loss or gain of Dsx in the gonadal soma is sufficient to mimic or rescue the phenotypes induced by Nup107 loss. Importantly, the aberrant phenotypes induced by compromising either Nup107 or dsx are reminiscent of bone morphogenetic protein (BMP signaling hyperactivation). Remarkably, in this context, the metalloprotease AdamTS-A, a transcriptional target of both Dsx and Nup107, is necessary for the calibration of BMP signaling. As modulation of BMP signaling is a conserved critical determinant of soma-germline interaction, the sex- and tissue-specific deployment of Dsx-F by Nup107 seems crucial for the maintenance of the homeostatic balance between the germ cells and somatic gonadal cells.


Assuntos
Aquaporinas , Proteínas de Drosophila , Animais , Proteínas de Ligação a DNA/metabolismo , Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Diferenciação Sexual/genética
10.
PLoS Genet ; 18(1): e1010002, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34986144

RESUMO

A critical step in animal development is the specification of primordial germ cells (PGCs), the precursors of the germline. Two seemingly mutually exclusive mechanisms are implemented across the animal kingdom: epigenesis and preformation. In epigenesis, PGC specification is non-autonomous and depends on extrinsic signaling pathways. The BMP pathway provides the key PGC specification signals in mammals. Preformation is autonomous and mediated by determinants localized within PGCs. In Drosophila, a classic example of preformation, constituents of the germ plasm localized at the embryonic posterior are thought to be both necessary and sufficient for proper determination of PGCs. Contrary to this longstanding model, here we show that these localized determinants are insufficient by themselves to direct PGC specification in blastoderm stage embryos. Instead, we find that the BMP signaling pathway is required at multiple steps during the specification process and functions in conjunction with components of the germ plasm to orchestrate PGC fate.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/embriologia , Células Germinativas/fisiologia , Animais , Blastoderma , Padronização Corporal , Diferenciação Celular , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Epigênese Genética , Feminino , Células Germinativas/metabolismo , Masculino , Transdução de Sinais
11.
J Pediatr Pharmacol Ther ; 27(8): 765-769, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36989008

RESUMO

Pediatric septic shock is a life-threatening condition with significant rates of morbidity and mortality. Standard management includes fluid resuscitation, timely antimicrobial administration, and epinephrine or norepinephrine if unresolved with initial management. Additional therapies are not well defined and include vasopressin, hydrocortisone, phenylephrine, levosimendan, dopamine, and others. Many of these agents modify cellular effects of calcium in the smooth muscle. The use of a calcium infusion may improve vasoactivity in the smooth muscle without the use of signaling pathways. Children are more susceptible to the effects of calcium, which may predispose them to enhanced vasoconstriction with the administration of intravenous calcium. We present a case in which a patient on chronic calcium channel blocker therapy presented with septic shock. She continued to remain hypotensive after fluid resuscitation, antibiotics, epinephrine, and norepinephrine. Her blood pressure improved with the initiation of a continuous calcium chloride infusion. Norepinephrine and epinephrine doses were decreased after the initiation of the calcium infusion.

12.
J Clin Monit Comput ; 36(3): 809-816, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33928469

RESUMO

The use of clinical scoring to assess for severity of respiratory distress and respiratory failure is challenging due to subjectivity and interrater variability. Transcutaneous Capnography (TcpCO2) can be used as an objective tool to assess a patient's ventilatory status. This study was designed to assess for any correlation of continuous monitoring of TcpCO2 with the respiratory clinical scores and deterioration in children admitted for acute respiratory distress. A prospective observational study over one year on children aged 2 weeks to 5 years admitted with acute respiratory distress or failure secondary to Bronchiolitis and Reactive airway disease was performed. Continuous TcpCO2 monitoring for upto 48 h was recorded. Investigators, bedside physicians, respiratory therapists, and nurses were blinded from the transcutaneous trends at the time of data collection. Total of 813 TcpCO2 measurements at standard intervals of 30 min were obtained on 38 subjects. Subjects with abnormal TcpCO2 (> 45 mmHg) were younger (6.9 ± 5.2 vs. 23.05 ± 17.7 months,) and were more likely to be on higher oxygen flow rate (0.52 L/min/kg vs 0.46 lier/min/kg, p = 0.004) and higher FiO2 (38.4 vs 33.6, p < 0.001 using heated high flow nasal cannula. No difference was found in bronchiolitis score or PEW score in subjects with normal and abnormal TcpCO2. A small but statistically significant increase in TcpCO2 was observed at the escalation of care. Even though odds of escalation of care are higher with abnormal TcpCO2 (OR 1.92), this difference did not reach statistical significance. pCO2 can provide additive information for non-invasive clinical monitoring of children requiring varying respiratory support; however, it does not provide predictive value for escalation or de-escalation of care.


Assuntos
Asma , Bronquiolite , Síndrome do Desconforto Respiratório , Monitorização Transcutânea dos Gases Sanguíneos , Dióxido de Carbono , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica
13.
Genetics ; 219(2)2021 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-34849887

RESUMO

Embryonic patterning is critically dependent on zygotic genome activation (ZGA). In Drosophila melanogaster embryos, the pioneer factor Zelda directs ZGA, possibly in conjunction with other factors. Here, we have explored the novel involvement of Chromatin-Linked Adapter for MSL Proteins (CLAMP) during ZGA. CLAMP binds thousands of sites genome-wide throughout early embryogenesis. Interestingly, CLAMP relocates to target promoter sequences across the genome when ZGA is initiated. Although there is a considerable overlap between CLAMP and Zelda binding sites, the proteins display distinct temporal dynamics. To assess whether CLAMP occupancy affects gene expression, we analyzed transcriptomes of embryos zygotically compromised for either clamp or zelda and found that transcript levels of many zygotically activated genes are similarly affected. Importantly, compromising either clamp or zelda disrupted the expression of critical segmentation and sex determination genes bound by CLAMP (and Zelda). Furthermore, clamp knockdown embryos recapitulate other phenotypes observed in Zelda-depleted embryos, including nuclear division defects, centrosome aberrations, and a disorganized actomyosin network. Based on these data, we propose that CLAMP acts in concert with Zelda to regulate early zygotic transcription.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas Nucleares/metabolismo , Zigoto/metabolismo , Animais , Sítios de Ligação , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Drosophila melanogaster , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Nucleares/química , Proteínas Nucleares/genética , Ligação Proteica , Zigoto/crescimento & desenvolvimento
14.
Nat Commun ; 12(1): 6094, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34667153

RESUMO

Zygotic genome activation (ZGA) initiates regionalized transcription underlying distinct cellular identities. ZGA is dependent upon dynamic chromatin architecture sculpted by conserved DNA-binding proteins. However, the direct mechanistic link between the onset of ZGA and the tissue-specific transcription remains unclear. Here, we have addressed the involvement of chromatin organizer Satb2 in orchestrating both processes during zebrafish embryogenesis. Integrative analysis of transcriptome, genome-wide occupancy and chromatin accessibility reveals contrasting molecular activities of maternally deposited and zygotically synthesized Satb2. Maternal Satb2 prevents premature transcription of zygotic genes by influencing the interplay between the pluripotency factors. By contrast, zygotic Satb2 activates transcription of the same group of genes during neural crest development and organogenesis. Thus, our comparative analysis of maternal versus zygotic function of Satb2 underscores how these antithetical activities are temporally coordinated and functionally implemented highlighting the evolutionary implications of the biphasic and bimodal regulation of landmark developmental transitions by a single determinant.


Assuntos
Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Fatores de Transcrição/metabolismo , Vertebrados/embriologia , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Animais , Cromatina/genética , Cromatina/metabolismo , Desenvolvimento Embrionário , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Proteínas de Ligação à Região de Interação com a Matriz/genética , Fatores de Transcrição/genética , Transcriptoma , Vertebrados/genética , Vertebrados/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Zigoto/metabolismo
15.
PLoS Genet ; 17(8): e1009685, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34343194

RESUMO

Gap junction (GJ) proteins, the primary constituents of GJ channels, are conserved determinants of patterning. Canonically, a GJ channel, made up of two hemi-channels contributed by the neighboring cells, facilitates transport of metabolites/ions. Here we demonstrate the involvement of GJ proteins during cuboidal to squamous epithelial transition displayed by the anterior follicle cells (AFCs) from Drosophila ovaries. Somatically derived AFCs stretch and flatten when the adjacent germline cells start increasing in size. GJ proteins, Innexin2 (Inx2) and Innexin4 (Inx4), functioning in the AFCs and germline respectively, promote the shape transformation by modulating calcium levels in the AFCs. Our observations suggest that alterations in calcium flux potentiate STAT activity to influence actomyosin-based cytoskeleton, possibly resulting in disassembly of adherens junctions. Our data have uncovered sequential molecular events underlying the cuboidal to squamous shape transition and offer unique insight into how GJ proteins expressed in the neighboring cells contribute to morphogenetic processes.


Assuntos
Conexinas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/crescimento & desenvolvimento , Células Epiteliais/fisiologia , Folículo Ovariano/fisiologia , Actomiosina/metabolismo , Animais , Padronização Corporal , Sinalização do Cálcio , Conexinas/genética , Citoesqueleto/metabolismo , Drosophila/metabolismo , Proteínas de Drosophila/genética , Células Epiteliais/metabolismo , Feminino , Morfogênese , Folículo Ovariano/metabolismo
16.
Elife ; 102021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34342574

RESUMO

During the essential and conserved process of zygotic genome activation (ZGA), chromatin accessibility must increase to promote transcription. Drosophila is a well-established model for defining mechanisms that drive ZGA. Zelda (ZLD) is a key pioneer transcription factor (TF) that promotes ZGA in the Drosophila embryo. However, many genomic loci that contain GA-rich motifs become accessible during ZGA independent of ZLD. Therefore, we hypothesized that other early TFs that function with ZLD have not yet been identified, especially those that are capable of binding to GA-rich motifs such as chromatin-linked adaptor for male-specific lethal (MSL) proteins (CLAMP). Here, we demonstrate that Drosophila embryonic development requires maternal CLAMP to (1) activate zygotic transcription; (2) increase chromatin accessibility at promoters of specific genes that often encode other essential TFs; and (3) enhance chromatin accessibility and facilitate ZLD occupancy at a subset of key embryonic promoters. Thus, CLAMP functions as a pioneer factor that plays a targeted yet essential role in ZGA.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Genoma de Inseto , Proteínas Nucleares/genética , Ativação Transcricional , Animais , Sequência de Bases , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas Nucleares/metabolismo , Zigoto/metabolismo
17.
J Pediatr Pharmacol Ther ; 26(3): 277-283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33833630

RESUMO

OBJECTIVE: Propofol is frequently used for outpatient sedation for pediatric patients, some of whom require multiple rounds of sedation for separate procedures within a short period. Anecdotal experience suggests that frequent use of propofol results in escalating doses; however, clinical evidence is unconvincing. This study was designed to evaluate if tolerance develops with frequent administration of propofol for children requiring multiple successive sedations. METHODS: A retrospective chart review of patients requiring multiple doses of propofol for separate procedures from 2011 through 2019 was conducted. Cumulative propofol dose and induction dose were analyzed using a mixed model for patients requiring sedation for serial procedures. RESULTS: Data from 24 different patients who required 3 or more sedations during the study period were analyzed. The number of sedations ranged from 3 to 28. The mean total propofol dose rate was 0.19 ± 0.14 mg/kg/min, and the mean induction dose was 3.2 ± 0.97 mg/kg. The total doses and induction doses were not statistically significantly different at different sedations (p = 0.089 and 0.180, respectively). There was a statistically significant decrease in the total dose as the time interval between 2 sedations increased (p < 0.001). CONCLUSIONS: Repeated administrations of propofol at time intervals used in outpatient sedation do not lead to the development of tolerance. A small decrease per day interval may be significant when propofol is used more frequently (multiple times per day or as a continuous drip) in an ICU setting.

18.
Sci Rep ; 11(1): 3385, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33564000

RESUMO

Special AT-rich binding protein-1 (SATB1) integrates higher-order chromatin architecture with gene regulation, thereby regulating multiple signaling pathways. In mammalian cells SATB1 directly interacts with ß-catenin and regulates the expression of Wnt targets by binding to their promoters. Whether SATB1 regulates Wnt/wg signaling by recruitment of ß-catenin and/or its interactions with other components remains elusive. Since Wnt/Wg signaling is conserved from invertebrates to humans, we investigated SATB1 functions in regulation of Wnt/Wg signaling by using mammalian cell-lines and Drosophila. Here, we present evidence that in mammalian cells, SATB1 interacts with Dishevelled, an upstream component of the Wnt/Wg pathway. Conversely, ectopic expression of full-length human SATB1 but not that of its N- or C-terminal domains in the eye imaginal discs and salivary glands of third instar Drosophila larvae increased the expression of Wnt/Wg pathway antagonists and suppressed phenotypes associated with activated Wnt/Wg pathway. These data argue that ectopically-provided SATB1 presumably modulates Wnt/Wg signaling by acting as negative regulator in Drosophila. Interestingly, comparison of SATB1 with PDZ- and homeo-domain containing Drosophila protein Defective Proventriculus suggests that both proteins exhibit limited functional similarity in the regulation of Wnt/Wg signaling in Drosophila. Collectively, these findings indicate that regulation of Wnt/Wg pathway by SATB1 is context-dependent.


Assuntos
Proteínas de Drosophila/metabolismo , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Via de Sinalização Wnt , Proteína Wnt1/metabolismo , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster , Células HEK293 , Humanos , Proteínas de Ligação à Região de Interação com a Matriz/genética , Proteína Wnt1/genética
19.
Elife ; 102021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33459591

RESUMO

Transcriptional quiescence, an evolutionarily conserved trait, distinguishes the embryonic primordial germ cells (PGCs) from their somatic neighbors. In Drosophila melanogaster, PGCs from embryos maternally compromised for germ cell-less (gcl) misexpress somatic genes, possibly resulting in PGC loss. Recent studies documented a requirement for Gcl during proteolytic degradation of the terminal patterning determinant, Torso receptor. Here we demonstrate that the somatic determinant of female fate, Sex-lethal (Sxl), is a biologically relevant transcriptional target of Gcl. Underscoring the significance of transcriptional silencing mediated by Gcl, ectopic expression of a degradation-resistant form of Torso (torsoDeg) can activate Sxl transcription in PGCs, whereas simultaneous loss of torso-like (tsl) reinstates the quiescent status of gcl PGCs. Intriguingly, like gcl mutants, embryos derived from mothers expressing torsoDeg in the germline display aberrant spreading of pole plasm RNAs, suggesting that mutual antagonism between Gcl and Torso ensures the controlled release of germ-plasm underlying the germline/soma distinction.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/embriologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Ligação a RNA/genética , Receptores Proteína Tirosina Quinases/genética , Processos de Determinação Sexual , Animais , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Embrião não Mamífero/embriologia , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Proteínas de Ligação a RNA/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Transcrição Gênica
20.
Lancet Child Adolesc Health ; 4(6): 444-454, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32407710

RESUMO

BACKGROUND: Very low birthweight or preterm infants are at increased risk of adverse outcomes including sepsis, necrotising enterocolitis, and death. We assessed whether supplementing the enteral diet of very low-birthweight infants with lactoferrin, an antimicrobial protein, reduces all-cause mortality or major morbidity. METHODS: We did a multicentre, double-blind, pragmatic, randomised superiority trial in 14 Australian and two New Zealand neonatal intensive care units. Infants born weighing less than 1500 g and aged less than 8 days, were eligible and randomly assigned (1:1) using minimising web-based randomisation to receive once daily 200 mg/kg pasteurised bovine lactoferrin supplements or no lactoferrin supplement added to breast or formula milk until 34 weeks' post-menstrual age (or for 2 weeks, if longer), or until discharge from the study hospital if that occurred first. Designated nurses preparing the daily feeds were not masked to group assignment, but other nurses, doctors, parents, caregivers, and investigators were unaware. The primary outcome was survival to hospital discharge or major morbidity (defined as brain injury, necrotising enterocolitis, late-onset sepsis at 36 weeks' post-menstrual age, or retinopathy treated before discharge) assessed in the intention-to-treat population. Safety analyses were by treatment received. We also did a prespecified, PRISMA-compliant meta-analysis, which included this study and other relevant randomised controlled trials, to estimate more precisely the effects of lactoferrin supplementation on late-onset sepsis, necrotising enterocolitis, and survival. This trial is registered with the Australian and New Zealand Clinical Trials Registry, ACTRN12611000247976. FINDINGS: Between June 27, 2014, and Sept 1, 2017, we recruited 1542 infants; 771 were assigned to the intervention group and 771 to the control group. One infant who had consent withdrawn before beginning lactoferrin treatment was excluded from analysis. In-hospital death or major morbidity occurred in 162 (21%) of 770 infants in the intervention group and in 170 (22%) of 771 infants in the control group (relative risk [RR] 0·95, 95% CI 0·79-1·14; p=0·60). Three suspected unexpected serious adverse reactions occurred; two in the lactoferrin group, namely unexplained late jaundice and inspissated milk syndrome, but were not attributed to the intervention and one in the control group had fatal inspissated milk syndrome. Our meta-analysis identified 13 trials completed before Feb 18, 2020, including this Article, in 5609 preterm infants. Lactoferrin supplements significantly reduced late-onset sepsis (RR 0·79, 95% CI 0·71-0·88; p<0·0001; I2=58%), but not necrotising enterocolitis or all-cause mortality. INTERPRETATION: Lactoferrin supplementation did not improve death or major morbidity in this trial, but might reduce late-onset sepsis, as found in our meta-analysis of over 5000 infants. Future collaborative studies should use products with demonstrated biological activity, be large enough to detect moderate and clinically important effects reliably, and assess greater doses of lactoferrin in infants at increased risk, such as those not exclusively receiving breastmilk or infants of extremely low birthweight. FUNDING: Australian National Health and Medical Research Council.


Assuntos
Cuidados Críticos/métodos , Suplementos Nutricionais , Mortalidade Hospitalar/tendências , Recém-Nascido de muito Baixo Peso , Unidades de Terapia Intensiva Neonatal , Lactoferrina/efeitos adversos , Austrália , Causas de Morte , Bases de Dados Factuais , Método Duplo-Cego , Feminino , Humanos , Recém-Nascido , Lactoferrina/administração & dosagem , Masculino , Morbidade , Nova Zelândia , Análise de Sobrevida
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