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1.
Mol Cell ; 81(16): 3294-3309.e12, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34293321

RESUMO

Temperature is a variable component of the environment, and all organisms must deal with or adapt to temperature change. Acute temperature change activates cellular stress responses, resulting in refolding or removal of damaged proteins. However, how organisms adapt to long-term temperature change remains largely unexplored. Here we report that budding yeast responds to long-term high temperature challenge by switching from chaperone induction to reduction of temperature-sensitive proteins and re-localizing a portion of its proteome. Surprisingly, we also find that many proteins adopt an alternative conformation. Using Fet3p as an example, we find that the temperature-dependent conformational difference is accompanied by distinct thermostability, subcellular localization, and, importantly, cellular functions. We postulate that, in addition to the known mechanisms of adaptation, conformational plasticity allows some polypeptides to acquire new biophysical properties and functions when environmental change endures.


Assuntos
Adaptação Fisiológica/genética , Proteoma/genética , Estresse Fisiológico/genética , Transcriptoma/genética , Aclimatação/genética , Animais , Exposição Ambiental/efeitos adversos , Regulação Fúngica da Expressão Gênica/genética , Temperatura Alta/efeitos adversos , Saccharomycetales/genética
2.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35058364

RESUMO

While there have been recent improvements in reducing bycatch in many fisheries, bycatch remains a threat for numerous species around the globe. Static spatial and temporal closures are used in many places as a tool to reduce bycatch. However, their effectiveness in achieving this goal is uncertain, particularly for highly mobile species. We evaluated evidence for the effects of temporal, static, and dynamic area closures on the bycatch and target catch of 15 fisheries around the world. Assuming perfect knowledge of where the catch and bycatch occurs and a closure of 30% of the fishing area, we found that dynamic area closures could reduce bycatch by an average of 57% without sacrificing catch of target species, compared to 16% reductions in bycatch achievable by static closures. The degree of bycatch reduction achievable for a certain quantity of target catch was related to the correlation in space and time between target and bycatch species. If the correlation was high, it was harder to find an area to reduce bycatch without sacrificing catch of target species. If the goal of spatial closures is to reduce bycatch, our results suggest that dynamic management provides substantially better outcomes than classic static marine area closures. The use of dynamic ocean management might be difficult to implement and enforce in many regions. Nevertheless, dynamic approaches will be increasingly valuable as climate change drives species and fisheries into new habitats or extended ranges, altering species-fishery interactions and underscoring the need for more responsive and flexible regulatory mechanisms.


Assuntos
Pesqueiros , Conservação dos Recursos Naturais , Ecossistema , Oceanografia
3.
Clin Otolaryngol ; 49(1): 124-129, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37867392

RESUMO

BACKGROUND/OBJECTIVES: Sinonasal inverted papilloma (IP) is a rare but serious diagnosis, with a paucity of patient-centred information regarding this condition. As more patients are seeking healthcare information online, the quality and comprehensibility of this information becomes ever more important. The aim of the study was to investigate the readability and quality of websites on inverted papilloma. METHODS: The term IP and seven of its synonyms were inputted into the three of the most commonly used search engines in the English-speaking world (Google, Yahoo and Bing). The first 20 results returned for each search term were then screened with our exclusion criteria. The remaining websites were assessed for their readability using the using the Flesch Reading Ease Score (FRES) and average grade level (AGL). Quality was assessed using the DISCERN questionnaire. RESULTS: Of the 480 websites returned using our search strategy, 410 were excluded using our screening criteria. Removal of duplicates from the remaining 70 websites left 14 for inclusion in the final analysis. The mean FRES score of the remaining websites was 30.5 ± 10 and the mean AGL was 15.2 ± 1.1, corresponding to a reading age of a 21-year-old. The median DISCERN score was 33.5 (30.5-36.5), a score which falls within the 'poor quality' range. CONCLUSION: The readability and quality of online patient information on IP is far below the expected standard. Healthcare providers have a responsibility to direct patients to appropriate sources of information or consider producing new material should a lack of appropriate sources exist.


Assuntos
Compreensão , Papiloma Invertido , Humanos , Adulto Jovem , Adulto , Ferramenta de Busca , Leitura , Inquéritos e Questionários , Internet
4.
Biomacromolecules ; 24(3): 1355-1365, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36827603

RESUMO

Retinal microglial/macrophage activation and optic nerve (ON) microglial/macrophage activation are glaucoma biomarkers and potential therapeutic targets for this blinding disease. We report targeting of activated microglia by PAMAM dendrimers in a rat glaucoma model and neuroprotection by N-acetylcysteine-conjugated dendrimer (D-NAC) conjugates in a post-injury rescue experiment. Intravitreally delivered fluorescently labeled dendrimer (D-Cy5) conjugates targeted and were retained in Iba-1-positive cells (90% at 7 days and 55% after 28 days) in the retina following intraocular pressure (IOP) elevation, while systemically delivered D-Cy5 targeted ON cells. A single intravitreal D-NAC dose given 1 week after IOP elevation significantly reduced transcription of pro-inflammatory (IL-6, MCP-1, IL-1ß) and A1 astrocyte (Serping1, Fkbp5, Amigo2) markers and increased survival of retinal ganglion cells (39 ± 12%) versus BSS- (20 ± 15%, p = 0.02) and free NAC-treated (26 ± 14%, p = 0.15) eyes. These results highlight the potential of dendrimer-targeted microglia and macrophages for early glaucoma detection and as a neuroprotective therapeutic target.


Assuntos
Dendrímeros , Glaucoma , Ratos , Animais , Microglia , Neuroproteção , Modelos Animais de Doenças
5.
Pituitary ; 26(2): 171-181, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36862265

RESUMO

PURPOSE: Transsphenoidal surgery is an established treatment for pituitary adenomas. We examined outcomes and time points following transsphenoidal surgery for pituitary adenoma to identify reporting heterogeneity within the literature. METHODS: A systematic review of studies that reported outcomes for transsphenoidal surgery for pituitary adenoma 1990-2021 were examined. The protocol was registered a priori and adhered to the PRISMA statement. Studies in English with > 10 patients (prospective) or > 500 patients (retrospective) were included. RESULTS: 178 studies comprising 427,659 patients were included. 91 studies reported 2 or more adenoma pathologies within the same study; 53 studies reported a single pathology. The most common adenomas reported were growth hormone-secreting (n = 106), non-functioning (n = 101), and ACTH-secreting (n = 95); 27 studies did not state a pathology. Surgical complications were the most reported outcome (n = 116, 65%). Other domains included endocrine (n = 104, 58%), extent of resection (n = 81, 46%), ophthalmic (n = 66, 37%), recurrence (n = 49, 28%), quality of life (n = 25, 19%); and nasal (n = 18, 10%). Defined follow up time points were most reported for endocrine (n = 56, 31%), extent of resection (n = 39, 22%), and recurrence (n = 28, 17%). There was heterogeneity in the follow up reported for all outcomes at different time points: discharge (n = 9), < 30 days (n = 23), < 6 months (n = 64), < 1 year (n = 23), and > 1 year (n = 69). CONCLUSION: Outcomes and follow up reported for transsphenoidal surgical resection of pituitary adenoma are heterogenous over the last 30 years. This study highlights the necessity to develop a robust, consensus-based, minimum, core outcome set. The next step is to develop a Delphi survey of essential outcomes, followed by a consensus meeting of interdisciplinary experts. Patient representatives should also be included. An agreed core outcome set will enable homogeneous reporting and meaningful research synthesis, ultimately improving patient care.


Assuntos
Adenoma , Neoplasias Hipofisárias , Humanos , Neoplasias Hipofisárias/cirurgia , Neoplasias Hipofisárias/patologia , Estudos Retrospectivos , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento , Adenoma/cirurgia , Adenoma/patologia , Medidas de Resultados Relatados pelo Paciente
6.
Neurocrit Care ; 38(3): 698-713, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36450971

RESUMO

BACKGROUND: Cilostazol, a phosphodiesterase III inhibitor, appears to be a promising agent for preventing cerebral ischemia in patients with aneurysmal subarachnoid hemorrhage. Here, the authors perform a systematic review and meta-analysis to quantitatively assess the effects of cilostazol on brain structural and functional outcomes in animal models of cerebral ischemia and subarachnoid hemorrhage-induced cerebral vasospasm. METHODS: By using the PRISMA guidelines, a search of the PubMed, Scopus, and Web of Science was conducted to identify relevant studies. Study quality of each included study for both systematic reviews were scored by using an adapted 15-item checklist from the Collaborative Approach to Meta-Analysis of Animal Data from Experimental Studies. We calculated a standardized mean difference as effect size for each comparison. For each outcome, comparisons were combined by using random-effects modeling to account for heterogeneity, with a restricted maximum likelihood estimate of between-study variance. RESULTS: A total of 22 (median [Q1, Q3] quality score of 7 [5, 8]) and 6 (median [Q1, Q3] quality score of 6 [6, 6]) studies were identified for cerebral ischemia and subarachnoid hemorrhage-induced cerebral vasospasm, respectively. Cilostazol significantly reduced the infarct volume in cerebral ischemia models with a pooled standardized mean difference estimate of - 0.88 (95% confidence interval [CI] [- 1.07 to - 0.70], p < 0.0001). Cilostazol significantly reduced neurofunctional deficits in cerebral ischemia models with a pooled standardized mean difference estimate of - 0.66 (95% CI [- 1.06 to - 0.28], p < 0.0001). Cilostazol significantly improved the basilar artery diameter in subarachnoid hemorrhage-induced cerebral vasospasm with a pooled standardized mean difference estimate of 2.30 (95% CI [0.94 to 3.67], p = 0.001). Cilostazol also significantly improved the basilar artery cross-section area with a pooled standardized mean estimate of 1.88 (95% CI [0.33 to 3.43], p < 0.05). Overall, there was between-study heterogeneity and asymmetry in the funnel plot observed in all comparisons. CONCLUSIONS: Published animal data support the overall efficacy of cilostazol in reducing infarct volume and neurofunctional deficits in cerebral ischemia models and cerebral vasospasm in subarachnoid hemorrhage models.


Assuntos
Isquemia Encefálica , Hemorragia Subaracnóidea , Vasoespasmo Intracraniano , Animais , Cilostazol/farmacologia , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/tratamento farmacológico , Vasoespasmo Intracraniano/tratamento farmacológico , Vasoespasmo Intracraniano/etiologia , Funções Verossimilhança , Infarto Cerebral , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Modelos Animais
7.
J Neurochem ; 161(1): 8-19, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34837399

RESUMO

Circadian genes in the medial accumbal shell (mNAcSh) region regulate binge alcohol consumption. Here, we investigated if antisense-induced knockdown of major circadian genes (Per1, Per2, and NPAS2) in the mNAcSh of mice exposed to intermittent access two-bottle choice (IA2BC) paradigm modulates the expression of histone deacetylase-2 (HDAC-2) and CREB-binding protein (CBP), key epigenetic modifiers associated with withdrawal-associated behaviors such as anxiety. Adult male C57BL/6J mice (N = 28), surgically implanted with bilateral guide cannulas above the mNAcSh, were chronically (4 weeks) exposed to alcohol (20% v/v) or saccharin (0.03%) via IA2BC paradigm. In the fourth week, a mixture of antisense (AS-ODNs; N = 14/group) or nonsense (NS-ODNs; N = 14/group) oligodeoxynucleotides against circadian genes were bilaterally infused into the mNAcSh. Subsequently, alcohol/saccharin consumption and preference were measured followed by euthanization of animals and verification of microinjection sites by visual inspection and the expression of HDAC-2 and CBP by using RT-PCR along with the verification of antisense-induced downregulation of circadian genes in the mNAcSh. As compared with NS-ODNs, AS-ODNs infusion significantly attenuated the alcohol-induced increase in HDAC-2 and reduction in CBP expression in the mNAcSh along with a significant reduction in alcohol consumption and preference. No significant effect was observed on either saccharin consumption or preference. Our results suggest that circadian genes in the mNAcSh may have a causal to play in mediating epigenetic changes observed after chronic alcohol consumption.


Assuntos
Proteína de Ligação a CREB , Núcleo Accumbens , Consumo de Bebidas Alcoólicas/genética , Consumo de Bebidas Alcoólicas/metabolismo , Animais , Proteína de Ligação a CREB/metabolismo , Regulação para Baixo , Etanol/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sacarina/metabolismo , Sacarina/farmacologia
8.
Addict Biol ; 27(2): e13133, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35032086

RESUMO

Circadian genes, including Per1, in the medial shell region of nucleus accumbens (mNAcSh), regulate binge alcohol consumption. However, the upstream mechanism regulating circadian genes-induced alcohol consumption is not known. Since activation of dopamine D2 receptors (D2R) increases Per1 gene expression, we hypothesised that local infusion of quinpirole, a D2R agonist, by increasing Per1 gene expression in the mNAcSh, will increase binge alcohol consumption in mice. We performed two experiments on male C57BL/6J mice, instrumented with bilateral guide cannulas above the mNAcSh, and exposed to a 4-day drinking-in-dark (DID) paradigm. The first experiment determined the effects of bilateral infusion of quinpirole (100 ng/300 nl/site) or DMSO (Vehicle group) in the mNAcSh on Per1 gene expression and alcohol consumption. The second experiment determined the effect of antisense-induced downregulation of Per1 in the mNAcSh on the quinpirole-induced increase in alcohol consumption. Control experiments were performed by exposing the animals to sucrose (10% w/v). After the experiment, animals were euthanised, brains removed and processed for localisation of injection sites and analysis of Per1 gene expression in the mNAcSh. As compared with the DMSO, local bilateral infusion of quinpirole significantly increased the expression of Per1 in the mNAcSh along with an increase in the amount of alcohol consumed in mice exposed to DID paradigm. In addition, local antisense-induced downregulation of Per1 significantly attenuated the effects of intro-accumbal infusion of quinpirole on alcohol consumption. Our results suggest that Per1 in the mNAcSh mediates D2R activation-induced increase in alcohol consumption.


Assuntos
Núcleo Accumbens , Receptores de Dopamina D2 , Consumo de Bebidas Alcoólicas/genética , Animais , Agonistas de Dopamina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Quimpirol/farmacologia , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/metabolismo
9.
Acta Neurochir (Wien) ; 164(4): 1115-1123, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35039959

RESUMO

INTRODUCTION: Depending on severity of presentation, pituitary apoplexy can be managed with acute surgery or non-operatively. We aim to assess long-term tumour control, visual and endocrinological outcomes following pituitary apoplexy with special emphasis on patients treated non-operatively. METHODS: Multicentre retrospective cohort study. All patients with symptomatic pituitary apoplexy were included. Patients were divided into 3 groups: group 1: surgery within 7 days; group 2: surgery 7 days-3 months; group 3: non-operative. Further intervention for oncological reasons during follow-up was the primary outcome. Secondary outcome measures included visual and endocrinological function at last follow-up. RESULTS: One hundred sixty patients were identified with mean follow-up of 48 months (n = 61 group 1; n = 34 group 2; n = 64 group 3). Factors influencing decision for surgical treatment included visual acuity loss (OR: 2.50; 95% CI: 1.02-6.10), oculomotor nerve palsy (OR: 2.80; 95% CI: 1.08-7.25) and compression of chiasm on imaging (OR: 9.50; 95% CI: 2.06-43.73). Treatment for tumour progression/recurrence was required in 17%, 37% and 24% in groups 1, 2 and 3, respectively (p = 0.07). Urgent surgery (OR: 0.16; 95% CI: 0.04-0.59) and tumour regression on follow-up (OR: 0.04; 95% CI: 0.04-0.36) were independently associated with long-term tumour control. Visual and endocrinological outcomes were comparable between groups. CONCLUSION: Urgent surgery is an independent predictor of long-term tumour control following pituitary apoplexy. However, 76% of patients who successfully complete 3 months of non-operative treatment may not require any intervention in the long term.


Assuntos
Apoplexia Hipofisária , Neoplasias Hipofisárias , Acidente Vascular Cerebral , Humanos , Apoplexia Hipofisária/diagnóstico por imagem , Apoplexia Hipofisária/cirurgia , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos , Acidente Vascular Cerebral/complicações , Resultado do Tratamento
10.
Biomacromolecules ; 22(8): 3574-3589, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34324818

RESUMO

Over two million people die of liver disorders every year globally. Hepatocytes are the key cells affected in several acute and chronic liver diseases. The current clinical outcomes of liver-targeted nanoparticles are limited, necessitating the need to develop smart hepatocyte-targeted drug delivery systems. Here, we present the rational design and development of a hepatocyte-targeting glycodendrimer (GAL-24) built from biocompatible building blocks, using expedite and facile chemical methodology. GAL-24 is designed to inherently target asialoglycoprotein receptor 1 (ASGP-R) on hepatocytes and shows significant accumulation in the liver (20% of injected dose), just 1 h after systemic administration. This is highly specific to hepatocytes, with over 80% of hepatocytes showing GAL-24-Cy5 signal at 24 h. GAL-24-Cy5 maintains hepatocyte-targeting capabilities in both a mouse model of severe acetaminophen poisoning-induced hepatic necrosis and a rat model of nonalcoholic steatohepatitis (NASH). This GAL-24 nanoplatform holds great promise for improved drug delivery to hepatocytes to combat many liver disorders.


Assuntos
Dendrímeros , Hepatopatias , Preparações Farmacêuticas , Animais , Sistemas de Liberação de Medicamentos , Galactose , Hepatócitos , Fígado , Hepatopatias/tratamento farmacológico , Camundongos , Ratos
11.
Alcohol Clin Exp Res ; 45(10): 1940-1949, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34424532

RESUMO

INTRODUCTION: We recently showed that circadian genes expressed in the shell region of nucleus accumbens (NAcSh) play a key role in alcohol consumption, though, the molecular mechanism of those effects is unclear. Because CREB-binding protein (CBP) promotes Per1 gene expression, we hypothesized that alcohol consumption would increase CBP expression in the NAcSh and antisense-induced knockdown of CBP would reduce Per1 expression and result in a reduction in alcohol consumption. METHODS: To test our hypothesis, we performed two experiments. The Drinking-in-the-dark (DID) paradigm was used to evaluate alcohol consumption in male C57BL/6J mice. In Experiment 1 we examined the effects of alcohol consumption on CBP gene expression in the NAcSh. Control animals were exposed to, sucrose [10% (w/v) taste and calorie] and water (consummatory behavior). In Experiment 2 examined the effects of CBP gene silencing on the expression of the Per1 gene in the NAcSh and alcohol consumption in mice exposed to alcohol using the DID paradigm. CBP gene silencing was achieved by local infusion of two doses of either CBP antisense oligodeoxynucleotides (AS-ODNs; Antisense group) or nonsense ODNs (NS-ODNs; Nonsense group) bilaterally microinjected into the NAcSh within 24 h before alcohol consumption on Day 4 of the DID paradigm. The microinfusion sites were verified by cresyl violet staining. RESULTS: Compared to sucrose, alcohol consumption, under the DID paradigm, significantly increased the expression of CBP in the NAcSh. Compared to Controls, bilateral infusion of CBP AS-ODNs significantly reduced the expression of Per1 in the NAcSh and alcohol consumption without affecting the amount of sucrose consumed. CONCLUSIONS: Our results suggest that CBP is an upstream regulator of Per1 expression in the NAcSh and may act via Per1 to modulate alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas/metabolismo , Proteína de Ligação a CREB/metabolismo , Núcleo Accumbens/metabolismo , Proteínas Circadianas Period/metabolismo , Animais , Elementos Antissenso (Genética) , Proteína de Ligação a CREB/genética , Técnicas de Silenciamento de Genes , Masculino , Camundongos Endogâmicos C57BL
12.
Alcohol Clin Exp Res ; 45(3): 530-542, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33606281

RESUMO

INTRODUCTIONS: Binge drinking is a deadly pattern of alcohol consumption. Evidence suggests that genetic variation in clock genes is strongly associated with alcohol misuse; however, the neuroanatomical basis for such a relationship is unknown. The shell region of the nucleus accumbens (NAcSh) is well known to play a role in binge drinking. Hence, we examined whether clock genes in the NAcSh regulate binge drinking. METHODS: To address this question, 2 experiments were performed on male C57BL/6J mice. In the first experiment, mice exposed to alcohol or sucrose under the 4-day drinking-in-the-dark (DID) paradigm were euthanized at 2 different time points on day 4 [7 hours after light (pre-binge drinking) or dark (post-binge drinking) onset]. The brains were processed for RT-PCR to examine the expression of circadian clock genes (Clock, Per1, and Per2) in the NAcSh and suprachiasmatic nucleus (SCN). In the second experiment, mice were exposed to alcohol, sucrose, or water as described above. On day 4, 1 hour prior to the onset of alcohol exposure, mice were bilaterally infused with either a mixture of circadian clock gene antisense oligodeoxynucleotides (AS-ODNs; antisense group) or nonsense/random ODNs (R-ODNs; control group) through surgically implanted cannulas above the NAcSh. Alcohol/sucrose/water consumption was measured for 4 hours. Blood alcohol concentration was measured to confirm binge drinking. Microinfusion sites were histologically verified using cresyl violet staining. RESULTS: As compared to sucrose, mice euthanized post-binge drinking (not pre-binge drinking) on day 4 displayed a greater expression of circadian genes in the NAcSh but not in the SCN. Knockdown of clock genes in the NAcSh caused a significantly lower volume of alcohol to be consumed on day 4 than in the control treatment. No differences were found in sucrose or water consumption. CONCLUSIONS: Our results suggest that clock genes in the NAcSh play a crucial role in binge drinking.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas/metabolismo , Proteínas CLOCK/biossíntese , Núcleo Accumbens/metabolismo , Oligonucleotídeos Antissenso/administração & dosagem , Proteínas Circadianas Period/biossíntese , Animais , Consumo Excessivo de Bebidas Alcoólicas/genética , Proteínas CLOCK/antagonistas & inibidores , Proteínas CLOCK/genética , Relógios Circadianos/efeitos dos fármacos , Relógios Circadianos/fisiologia , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Etanol/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microinjeções/métodos , Núcleo Accumbens/efeitos dos fármacos , Proteínas Circadianas Period/antagonistas & inibidores , Proteínas Circadianas Period/genética
13.
J Surg Res ; 260: 177-189, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33348169

RESUMO

BACKGROUND: Hypothermic circulatory arrest (HCA) is associated with neurologic morbidity, in part mediated by activation of the N-methyl-D-aspartate glutamate receptor causing excitotoxicity and neuronal apoptosis. Using a canine model, we hypothesized that the N-methyl-D-aspartate receptor antagonist MK801 would provide neuroprotection and that MK801 conjugation to dendrimer nanoparticles would improve efficacy. MATERIALS AND METHODS: Male hound dogs were placed on cardiopulmonary bypass, cooled to 18°C, and underwent 90 min of HCA. Dendrimer conjugates (d-MK801) were prepared by covalently linking dendrimer surface OH groups to MK801. Six experimental groups received either saline (control), medium- (0.15 mg/kg) or high-dose (1.56 mg/kg) MK801, or low- (0.05 mg/kg), medium-, or high-dose d-MK801. At 24, 48, and 72 h after HCA, animals were scored by a standardized neurobehavioral paradigm (higher scores indicate increasing deficits). Cerebrospinal fluid was obtained at baseline, eight, 24, 48, and 72 h after HCA. At 72 h, brains were examined for histopathologic injury in a blinded manner (higher scores indicate more injury). RESULTS: Neurobehavioral deficit scores were reduced by low-dose d-MK801 on postoperative day two (P < 0.05) and by medium-dose d-MK801 on postoperative day 3 (P = 0.05) compared with saline controls, but free drug had no effect. In contrast, high-dose free MK801 significantly improved histopathology scores compared with saline (P < 0.05) and altered biomarkers of injury in cerebrospinal fluid, with a significant reduction in phosphorylated neurofilament-H for high-dose MK801 versus saline (P < 0.05). CONCLUSIONS: Treatment with MK-801 demonstrated significant improvement in neurobehavioral and histopathology scores after HCA, although not consistently across doses and conjugates.


Assuntos
Parada Circulatória Induzida por Hipotermia Profunda/efeitos adversos , Maleato de Dizocilpina/farmacologia , Fármacos Neuroprotetores/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Animais , Encéfalo/patologia , Cognição , Cães , Masculino
14.
Br J Neurosurg ; 35(4): 408-417, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32909855

RESUMO

BACKGROUND: The endonasal transsphenoidal approach (TSA) has emerged as the preferred approach in order to treat pituitary adenoma and related sellar pathologies. The recently adopted expanded endonasal approach (EEA) has improved access to the ventral skull base whilst retaining the principles of minimally invasive surgery. Despite the advantages these approaches offer, cerebrospinal fluid (CSF) rhinorrhoea remains a common complication. There is currently a lack of comparative evidence to guide the best choice of skull base reconstruction, resulting in considerable heterogeneity of current practice. This study aims to determine: (1) the scope of the methods of skull base repair; and (2) the corresponding rates of postoperative CSF rhinorrhoea in contemporary neurosurgical practice in the UK and Ireland. METHODS: We will adopt a multicentre, prospective, observational cohort design. All neurosurgical units in the UK and Ireland performing the relevant surgeries (TSA and EEA) will be eligible to participate. Eligible cases will be prospectively recruited over 6 months with 6 months of postoperative follow-up. Data points collected will include: demographics, tumour characteristics, operative data), and postoperative outcomes. Primary outcomes include skull base repair technique and CSF rhinorrhoea (biochemically confirmed and/or requiring intervention) rates. Pooled data will be analysed using descriptive statistics. All skull base repair methods used and CSF leak rates for TSA and EEA will be compared against rates listed in the literature. ETHICS AND DISSEMINATION: Formal institutional ethical board review was not required owing to the nature of the study - this was confirmed with the Health Research Authority, UK. CONCLUSIONS: The need for this multicentre, prospective, observational study is highlighted by the relative paucity of literature and the resultant lack of consensus on the topic. It is hoped that the results will give insight into contemporary practice in the UK and Ireland and will inform future studies.


Assuntos
Rinorreia de Líquido Cefalorraquidiano , Vazamento de Líquido Cefalorraquidiano , Rinorreia de Líquido Cefalorraquidiano/epidemiologia , Rinorreia de Líquido Cefalorraquidiano/etiologia , Rinorreia de Líquido Cefalorraquidiano/cirurgia , Estudos de Coortes , Humanos , Complicações Pós-Operatórias , Estudos Prospectivos , Estudos Retrospectivos , Base do Crânio/cirurgia
15.
J Electron Mater ; 50(12): 7085-7097, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34690411

RESUMO

The ion-sensitive field-effect transistor (ISFET) is a popular technology utilized for pH sensing applications. In this work, we have presented the fabrication, characterization, and electrochemical modeling of an aluminum oxide (Al2O3)-gate ISFET-based pH sensor. The sensor is fabricated using well-established metal-oxide-semiconductor (MOS) unit processes with five steps of photolithography, and the sensing film is patterned using the lift-off process. The Al2O3 sensing film is deposited over the gate area using pulsed-DC magnetron-assisted reactive sputtering technique in order to improve the sensor performance. The material characterization of sensing film has been done using x-ray diffraction, field-emission scanning electron microscopy, energy-dispersive spectroscopy, and x-ray photoelectron spectroscopy techniques. The sensor has been packaged using thick-film technology and encapsulated by a dam-and-fill approach. The packaged device has been tested in various pH buffer solutions, and a sensitivity of nearly 42.1 mV/pH has been achieved. A simulation program with integrated circuit emphasis (SPICE) macromodel of the Al2O3-gate ISFET is empirically derived from the experimental results, and the extracted electrochemical parameters have been reported. The drift and hysteresis characteristics of the Al2O3-gate ISFET were also studied, and the obtained drift rates for different pH buffer solutions of 4, 7, and 10 are 0.136 µA/min, 0.124 µA/min, and 0.108 µA/min, respectively. A hysteresis of nearly 5.806 µA has been obtained. The developed sensor has high sensitivity along with low drift and hysteresis.

16.
IEEE Trans Instrum Meas ; 70: 6502210, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-37982042

RESUMO

The time-series forecasting makes a substantial contribution in timely decision-making. In this article, a recently developed eigenvalue decomposition of Hankel matrix (EVDHM) along with the autoregressive integrated moving average (ARIMA) is applied to develop a forecasting model for nonstationary time series. The Phillips-Perron test (PPT) is used to define the nonstationarity of time series. EVDHM is applied over a time series to decompose it into respective subcomponents and reduce the nonstationarity. ARIMA-based model is designed to forecast the future values for each subcomponent. The forecast values of each subcomponent are added to get the final output values. The optimized value of ARIMA parameters for each subcomponent is obtained using a genetic algorithm (GA) for minimum values of Akaike information criterion (AIC). Model performance is evaluated by estimating the future values of daily new cases of the recent pandemic disease COVID-19 for India, USA, and Brazil. The high efficacy of the proposed method is convinced with the results.

17.
Proteomics ; 20(5-6): e1800407, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32068959

RESUMO

Aging biology is intimately associated with dysregulated metabolism, which is one of the hallmarks of aging. Aging-related pathways such as mTOR and AMPK, which are major targets of anti-aging interventions including rapamcyin, metformin, and exercise, either directly regulate or intersect with metabolic pathways. In this review, numerous candidate bio-markers of aging that have emerged using metabolomics are outlined. Metabolomics studies also reveal that not all metabolites are created equally. A set of core "hub" metabolites are emerging as central mediators of aging. The hub metabolites reviewed here are nicotinamide adenine dinucleotide, reduced nicotinamide dinucleotide phosphate, α-ketoglutarate, and ß-hydroxybutyrate. These "hub" metabolites have signaling and epigenetic roles along with their canonical roles as co-factors or intermediates of carbon metabolism. Together these hub metabolites suggest a central role of the TCA cycle in signaling and metabolic dysregulation associated with aging.


Assuntos
Envelhecimento , Redes e Vias Metabólicas , Metaboloma , Ácido 3-Hidroxibutírico/genética , Ácido 3-Hidroxibutírico/metabolismo , Animais , Biomarcadores/metabolismo , Ciclo do Ácido Cítrico , Dano ao DNA , Epigênese Genética , Humanos , Ácidos Cetoglutáricos/metabolismo , Metabolômica/métodos , NAD/genética , NAD/metabolismo , NADP/genética , NADP/metabolismo
18.
Biomacromolecules ; 21(9): 3909-3922, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32786523

RESUMO

Mitochondria mediate critical cellular processes, including proliferation, apoptosis, and immune responses; as such, their dysfunction is pathogenic in many neurodegenerative disorders and cancers. In glioblastoma, targeted delivery of mitochondria-focused anticancer therapies has failed to translate into clinical success due to the nonspecific cellular localization, heterogeneity of receptor expression across patients, poor transport across biological barriers to reach the brain, tumor, and mitochondria, and systemic side effects. Strategies that can overcome brain and solid tumor barriers and selectively target mitochondria within specific cell types may lead to improvements in glioblastoma treatment. Developments in dendrimer-mediated nanomedicines have shown promise targeting tumor-associated macrophages (TAMs) in glioblastoma, following systemic administration. Here, we present a novel dendrimer conjugated to the translocator protein (18 kDa) (TSPO) ligand 5,7-dimethylpyrazolo[1,5-α]pyrimidin-3-ylacetamide (DPA). We developed a clickable DPA for conjugation on the dendrimer surface and demonstrated in vitro that the dendrimer-DPA conjugate (D-DPA) significantly increases dendrimer colocalization with mitochondria. Compared to free TSPO ligand PK11195, D-DPA stimulates greater antitumor immune signaling. In vivo, we show that D-DPA targets mitochondria specifically within TAMs following systemic administration. Our results demonstrate that dendrimers can achieve TAM-specific targeting in glioblastoma and can be further modified to target specific intracellular compartments for organelle-specific drug delivery.


Assuntos
Dendrímeros , Glioblastoma , Linhagem Celular Tumoral , Dendrímeros/farmacologia , Dendrímeros/uso terapêutico , Glioblastoma/tratamento farmacológico , Humanos , Ligantes , Mitocôndrias , Receptores de GABA/uso terapêutico , Macrófagos Associados a Tumor
19.
Biomacromolecules ; 21(12): 5148-5161, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33112134

RESUMO

Glioblastoma exhibits high mortality rates due to challenges with drug delivery to the brain and into solid tumors. This two-pronged barrier necessitates high doses of systemic therapies, resulting in significant off-target toxicities. Recently, dendrimer-nanomedicines (without ligands) have shown promise for targeting specific cells in brain tumors from systemic circulation, for improved efficacy and amelioration of systemic toxicities. A dendrimer-rapamycin conjugate (D-Rapa) is presented here that specifically targets tumor-associated macrophages (TAMs) in glioblastoma from systemic administration. D-Rapa improves suppression of pro-tumor expression in activated TAMs and antiproliferative properties of rapamycin in glioma cells in vitro. In vivo, D-Rapa localizes specifically within TAMs, acting as depots to release rapamycin into the tumor microenvironment. This targeted delivery strategy yields improved reduction in tumor burden and systemic toxicities in a challenging, clinically relevant orthotopic syngeneic model of glioblastoma, demonstrating the significant potential of dendrimers as targeted immunotherapies for improving glioblastoma treatment, still an unmet need.


Assuntos
Neoplasias Encefálicas , Dendrímeros , Glioblastoma , Neoplasias Encefálicas/tratamento farmacológico , Dendrímeros/uso terapêutico , Sistemas de Liberação de Medicamentos , Glioblastoma/tratamento farmacológico , Humanos , Sirolimo/farmacologia , Microambiente Tumoral , Macrófagos Associados a Tumor
20.
Muscle Nerve ; 60(2): 155-160, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31032944

RESUMO

INTRODUCTION: Existing normal value references for pediatric nerve conduction studies (NCS) are based on limited sample sizes with uncertain reliability, suggesting a need for better normative data. METHODS: Electronic medical records were reviewed for pediatric patients (0 to <18 years) with normal findings on electromyography and NCS during the period from January 1, 1997 through September 20, 2017. Electrodiagnostic and demographic data were collected. Gaussian and descriptive statistics were used to establish normal values by age group. RESULTS: In this study we analyzed 1,918 normal NCS on 1,849 unique pediatric patients. Patients were stratified by age: 0 to <1 month; 1 to <6 months; 6 to <12 months; 12 to <24 months; 2 to <3 years; 3 to <4 years; 4 to <5 years; 5 to <10 years; 10 to <15 years; and 15 to <18 years. Normal reference ranges for amplitude, conduction velocity, and distal latency were established for each age group for 4 motor and 4 sensory nerves. DISCUSSION: The large sample size of this study provides reliable reference values for interpreting pediatric NCS. Muscle Nerve 60: 155-160, 2019.


Assuntos
Eletromiografia , Condução Nervosa/fisiologia , Nervos Periféricos/fisiopatologia , Adolescente , Criança , Pré-Escolar , Eletrodiagnóstico , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Valores de Referência
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