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1.
Environ Sci Technol ; 57(43): 16575-16584, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37856469

RESUMO

Septic tanks in low- and middle-income countries are often not emptied for a long time, potentially resulting in poor pollutant removal efficiency and increased greenhouse gas emissions, including methane (CH4). We examined the impact of long emptying intervals (4.0-23 years) on the biochemical oxygen demand (BOD) removal efficiency of 15 blackwater septic tanks and the CH4 emission rates of 23 blackwater septic tanks in Hanoi. The average BOD removal efficiency was 37% (-2-65%), and the average CH4 emission rate was 10.9 (2.2-26.8) g/(cap·d). The emptying intervals were strongly negatively correlated with BOD removal efficiency (R = -0.676, p = 0.006) and positively correlated with CH4 emission rates (R = 0.614, p = 0.001). CH4 emission rates were positively correlated with sludge depth (R = 0.596, p = 0.002), but against expectation, negatively correlated with BOD removal efficiency (R = -0.219, p = 0.451). These results suggest that shortening the emptying interval improves the BOD removal efficiency and reduces the CH4 emission rate. Moreover, the CH4 emission estimation of the Intergovernmental Panel on Climate Change, which is a positive conversion of BOD removal, might be inaccurate for septic tanks with long emptying intervals. Our findings suggest that emptying intervals, sludge depth, and per-capita emission factors reflecting long emptying intervals are potential parameters for accurately estimating CH4 emissions from septic tanks.


Assuntos
Gases de Efeito Estufa , Metano , Metano/análise , Esgotos , Mudança Climática
2.
Materials (Basel) ; 16(14)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37512184

RESUMO

We report on the far-infrared, temperature-dependent optical properties of a CrI3 transition metal halide single crystal, a van der Waals ferromagnet (FM) with a Curie temperature of 61 K. In addition to the expected phonon modes determined by the crystalline symmetry, the optical reflectance and transmittance spectra of CrI3 single crystals show many other excitations as a function of temperature as a consequence of the combination of a strong lattice anharmonicity and spin-phonon coupling. This complex vibrational spectrum highlights the presence of entangled interactions among the different degrees of freedom in CrI3.

3.
Prosthet Orthot Int ; 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37498781

RESUMO

Women living with limb loss (amputees) have unique needs that increase during pregnancy. Comfort, pain, and activity are exponentially compromised. Changes in mass and altered center of gravity increase the likelihood of falls and compromise safety for the mother and unborn baby. Subjective and physical functional performance measures data was collected through 2 separate pregnancies on a 36-year-old woman with a right transfemoral amputation. Physiological changes during pregnancy effected comfort, pain, and functional performance. Clinical practice guidelines for prosthetic management should be established to include protocols such as adjustment schedules, specialized socket design, and necessary component changes throughout the course of pregnancy.

4.
Nano Lett ; 22(17): 7034-7041, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36039834

RESUMO

Two-dimensional van der Waals magnetic semiconductors display emergent chemical and physical properties and hold promise for novel optical, electronic and magnetic "few-layers" functionalities. Transition-metal iodides such as CrI3 and VI3 are relevant for future electronic and spintronic applications; however, detailed experimental information on their ground state electronic properties is lacking often due to their challenging chemical environment. By combining X-ray electron spectroscopies and first-principles calculations, we report a complete determination of CrI3 and VI3 electronic ground states. We show that the transition metal-induced orbital filling drives the stabilization of distinct electronic phases: a wide bandgap in CrI3 and a Mott insulating state in VI3. Comparison of surface-sensitive (angular-resolved photoemission spectroscopy) and bulk-sensitive (X-ray absorption spectroscopy) measurements in VI3 reveals a surface-only V2+ oxidation state, suggesting that ground state electronic properties are strongly influenced by dimensionality effects. Our results have direct implications in band engineering and layer-dependent properties of two-dimensional systems.

5.
Sci Rep ; 11(1): 23405, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34862444

RESUMO

We report on the optical properties from terahertz (THz) to Near-Infrared (NIR) of the layered magnetic compound CrI3 at various temperatures, both in the paramagnetic and ferromagnetic phase. In the NIR spectral range, we observe an insulating electronic gap around 1.1 eV which strongly hardens with decreasing temperature. The blue shift observed represents a record in insulating materials and it is a fingerprint of a strong electron-phonon interaction. Moreover, a further gap hardening is observed below the Curie temperature, indicating the establishment of an effective interaction between electrons and magnetic degrees of freedom in the ferromagnetic phase. Similar interactions are confirmed by the disappearance of some phonon modes in the same phase, as expected from a spin-lattice interaction theory. Therefore, the optical properties of CrI3 reveal a complex interaction among electronic, phononic and magnetic degrees of freedom, opening many possibilities for its use in 2-Dimensional heterostructures.

6.
Prosthet Orthot Int ; 45(4): 304-312, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33856157

RESUMO

BACKGROUND: There are alternative transfemoral (TF) socket interface designs that have not been compared with the standard of care, ischial ramus containment (IRC). The interface directly affects performance. OBJECTIVES: To compare 3 TF interface designs, IRC, dynamic socket (DS), and subischial (Sub-I), regarding gait, balance, mobility, and preference. The authors hypothesized that these more active users may experience gait, mobility, and preference benefits from the less intrusive DS and Sub-I interface designs. STUDY DESIGN: Single-blind, repeated-measures, 3-period randomized controlled crossover clinical trial. METHODS: People with unilateral TF amputation with 1 year or longer prosthesis use experience, independent community ambulatory status, 18 to 60 years of age, of any race or ethnicity, with a body mass of 45 to 125 kg, and with a self-reported ability to walk for 20 minutes continuously were included in the study. Each participant was fit in all 3 interface designs. RESULTS: Thirteen participants completed the clinical trial. Velocity, cadence, mobility, and balance were not statistically different between the 3 socket conditions. The DS demonstrated significantly greater symmetry in swing, stance, single support percentage, and toe angle compared with IRC and Sub-I. Sixty days after study completion, 7 participants changed interfaces, trending away from IRC. CONCLUSIONS: Large differences were not observed. Small differences in spatiotemporal gait measures combined with patient preference may make a meaningful difference to individual patients and should be considered.


Assuntos
Membros Artificiais , Amputação Cirúrgica , Marcha , Humanos , Desenho de Prótese , Método Simples-Cego
7.
Chem Rev ; 121(5): 2935-2965, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32955868

RESUMO

Hexagonal perovskites, in contrast to the more familiar perovskites, when oxides, allow for face-sharing of metal-oxygen octahedra or trigonal prisms within their structural frameworks. This results in dimers, trimers, tetramers, or longer fragments of chains of face-sharing octahedra in the crystal structures, and consequently in much shorter metal-metal distances and lower metal-oxygen-metal bond angles than are seen in the more familiar perovskites. The presence of the face-sharing octahedra can have a dramatic impact on magnetic properties of these compounds, and dimer-based materials, in particular, have been the subjects of many quantum-materials-directed studies in materials physics. Hexagonal oxide perovskites are also of contemporary interest due to their potential for geometrical frustration of the ordering of magnetic moments or orbital occupancies at low temperatures, which is especially relevant to their significance as quantum materials. As such, several hexagonal oxide perovskites have been identified as potential candidates for hosting the quantum-spin-liquid state at low temperatures. In our view, hexagonal oxide perovskites are fertile ground for finding new quantum materials. This review briefly describes the solid state chemistry of many of these materials.

8.
Prosthet Orthot Int ; 44(3): 145-154, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32308126

RESUMO

BACKGROUND: The most crucial aspect of a prosthesis is the socket, as it will directly determine gait stability and quality. The current standard of care ischial ramus containment socket is reported to increase coronal stability through gait; however, socket discomfort is the primary complaint among prosthetic users. OBJECTIVES: The purpose of this study is to compare ischial ramus containment to alternatives in the transfemoral amputee population. All subjects were fit with three different sockets: traditional ischial ramus containment, a dynamic socket, and a sub-ischial. In this study, authors hypothesized socket skeletal motion would be equivalent across interventions. STUDY DESIGN: Single-blind, repeated-measures, three-period randomized crossover clinical trial. METHODS: Outcome measures were socket comfort score and skeletal motion, viewed coronally with X-ray measuring the position of the skeleton in relationship to the socket in full weight-bearing and full un-loading. RESULTS: The mean age was 38.2 and mean Amputee Mobility Predictor score was 40. Mean vertical movement, horizontal movement, single limb prosthetic stance, mean femoral adduction in swing and stance, and median socket comfort score were not statistically different. CONCLUSION: The socket design did not significantly effect skeletal motion and socket comfort. All socket designs are suitable depending on the patient-centric preferences and prosthetist skill set. CLINICAL RELEVANCE: The comfort of the standard of care transfemoral amputation socket has been widely reported as problematic. A comparison of alternative designs in a controlled clinical trial environment will assist the clinician in understanding the impact of design regarding skeletal motion and comfort. Users could benefit from alternatives applied in clinical practice.


Assuntos
Membros Artificiais , Desenho de Prótese/instrumentação , Ajuste de Prótese/instrumentação , Suporte de Carga , Adulto , Feminino , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Método Simples-Cego
9.
Nat Commun ; 10(1): 1357, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-30902983

RESUMO

A fundamental question in biology is how vertebrates evolved and differ from invertebrates, and little is known about differences in the regulation of translation in the two systems. Herein, we identify a threonyl-tRNA synthetase (TRS)-mediated translation initiation machinery that specifically interacts with eIF4E homologous protein, and forms machinery that is structurally analogous to the eIF4F-mediated translation initiation machinery via the recruitment of other translation initiation components. Biochemical and RNA immunoprecipitation analyses coupled to sequencing suggest that this machinery emerged as a gain-of-function event in the vertebrate lineage, and it positively regulates the translation of mRNAs required for vertebrate development. Collectively, our findings demonstrate that TRS evolved to regulate vertebrate translation initiation via its dual role as a scaffold for the assembly of initiation components and as a selector of target mRNAs. This work highlights the functional significance of aminoacyl-tRNA synthetases in the emergence and control of higher order organisms.


Assuntos
Iniciação Traducional da Cadeia Peptídica , Treonina-tRNA Ligase/metabolismo , Sequência de Aminoácidos , Animais , Vasos Sanguíneos/crescimento & desenvolvimento , Vasos Sanguíneos/metabolismo , Fator de Iniciação 4E em Eucariotos , Fator de Iniciação 4F em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Células HEK293 , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Ligação Proteica , Proteínas de Ligação ao Cap de RNA/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Especificidade da Espécie , Treonina-tRNA Ligase/química , Vertebrados/crescimento & desenvolvimento , Vertebrados/metabolismo , Peixe-Zebra
10.
Microbes Infect ; 19(1): 5-17, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27637463

RESUMO

Mycobacterial ESX systems are often related to pathogenesis during infection. However, little is known about the function of ESX systems of Mycobacterium abscessus (Mab). This study focuses on the Mab ESX-3 cluster, which contains major genes such as esxH (Rv0288, low molecular weight protein antigen 7; CFP-7) and esxG (Rv0287, ESAT-6 like protein). An esx-3 (MAB 2224c-2234c)-deletional mutant of Mab (Δesx) was constructed and used to infect murine and human macrophages. We then investigated whether Mab Δesx modulated innate host immune responses in macrophages. Mab Δesx infection resulted in less pathological and inflammatory responses. Additionally, Δesx resulted in significantly decreased activation of inflammatory signaling and cytokine production in macrophages compared to WT. Moreover, recombinant EsxG·EsxH (rEsxGH) proteins encoded by the ESX-3 region showed synergistic enhancement of inflammatory cytokine generation in macrophages infected with Δesx. Taken together, our data suggest that Mab ESX-3 plays an important role in inflammatory and pathological responses during Mab infection.


Assuntos
Proteínas de Bactérias/metabolismo , Família Multigênica , Mycobacterium/patogenicidade , Fatores de Virulência/metabolismo , Animais , Proteínas de Bactérias/genética , Citocinas/metabolismo , Feminino , Deleção de Genes , Voluntários Saudáveis , Humanos , Imunidade Inata , Ativação de Macrófagos , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos Endogâmicos C57BL , Mycobacterium/genética , Fatores de Virulência/genética
11.
J Microbiol Biotechnol ; 26(2): 432-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26643967

RESUMO

Shiga toxins (Stxs) produced by Shiga toxin-producing Escherichia coli (STEC) strains are major virulence factors that cause fatal systemic complications, such as hemolytic uremic syndrome and disruption of the central nervous system. Although numerous studies report proinflammatory responses to Stx type 1 (Stx1) or Stx type 2 (Stx2) both in vivo and in vitro, none have examined dynamic immune regulation involving cytokines and/or unknown inflammatory mediators during intoxication. Here, we showed that enzymatically active Stxs trigger the dissociation of lysyl-tRNA synthetase (KRS) from the multi-aminoacyl-tRNA synthetase complex in human macrophage-like differentiated THP-1 cells and its subsequent secretion. The secreted KRS acted to increase the production of proinflammatory cytokines and chemokines. Thus, KRS may be one of the key factors that mediate transduction of inflammatory signals in the STEC-infected host.


Assuntos
Lisina-tRNA Ligase/metabolismo , Macrófagos/imunologia , Toxinas Shiga/farmacologia , Aminoacil-tRNA Sintetases/isolamento & purificação , Aminoacil-tRNA Sintetases/metabolismo , Linhagem Celular , Quimiocinas/metabolismo , Citocinas/metabolismo , Escherichia coli O157/genética , Humanos , Toxinas Shiga/metabolismo , Toxinas Shiga/toxicidade , Escherichia coli Shiga Toxigênica
12.
Biochem Biophys Res Commun ; 467(2): 218-22, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26453009

RESUMO

In addition to the active cysteines located at positions 32 and 35 in humans, mammalian cytosolic thioredoxin (TRX) possesses additional conserved cysteine residues at positions 62, 69, and 73. These non-canonical cysteine residues, that are distinct from prokaryotic TRX and also not found in mammalian mitochondrial TRX, have been implicated in biological functions regulating signal transduction pathways via their post-translational modifications. Here, we describe for the first time the structure of a fully oxidized TRX. The structure shows a non-active Cys62-Cys69 disulfide bond in addition to the active Cys32-Cys35 disulfide. The non-active disulfide switches the α3-helix of TRX, composed of residues Cys62 to Glu70, to a bulging loop and dramatically changes the environment of the TRX residues involved in the interaction with its reductase and other cellular substrates. This structural modification may have implications for a number of potential functions of TRX including the regulation of redox-dependent signaling pathways.


Assuntos
Cisteína/química , Dissulfetos/química , Tiorredoxinas/química , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Humanos , Modelos Moleculares , Oxirredução , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Tiorredoxinas/genética
13.
Sex Health ; 12(4): 328-35, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26005058

RESUMO

UNLABELLED: Background Evidence regarding whether male partners' characteristics can influence women's likelihood of getting sexually transmissible infections (STIs) is insufficient and inconsistent. Our study examined associations between women's perception of primary male partners' demographic and behavioural characteristics and women's history of bacterial STI diagnoses among 126 women at risk for STIs in Ho Chi Minh City, Vietnam. METHODS: All variables were obtained by women's self-report. Due to the excess zeroes of the number of bacterial STI diagnoses for women, we used Zero-Inflated Poisson regression to examine associations of interest. RESULTS: Among women who had one lifetime male partner (n=49), the partner's number of female sexual partners [prevalence ratio (PR)=4.63, 95%CI=1.44-14.88] and number of STI diagnoses (PR=27.32, 95%CI=1.56-477.70) were associated with the woman's number of bacterial STI diagnoses, after adjusting for women's education level. For women who had >1 lifetime male partner (n=77), a greater number of women's bacterial STI diagnoses was also associated with their partners' STI history (PR=9.12, 95% CI=2.44-34.11). CONCLUSIONS: An increased risk for STIs in women was associated with both individual characteristics and their primary male partner's behavioural risk factors. Therefore, primary male partners' risk factors should be included in STI risk assessments, treatment and interventions for women.

14.
Nat Commun ; 6: 6115, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25655831

RESUMO

Excessive activation of the NLRP3 inflammasome results in damaging inflammation, yet the regulators of this process remain poorly defined. Herein, we show that the orphan nuclear receptor small heterodimer partner (SHP) is a negative regulator of NLRP3 inflammasome activation. NLRP3 inflammasome activation leads to an interaction between SHP and NLRP3, proteins that are both recruited to mitochondria. Overexpression of SHP competitively inhibits binding of NLRP3 to apoptosis-associated speck-like protein containing a CARD (ASC). SHP deficiency results in increased secretion of proinflammatory cytokines IL-1ß and IL-18, and excessive pathologic responses typically observed in mouse models of kidney tubular necrosis and peritoneal gout. Notably, the loss of SHP results in accumulation of damaged mitochondria and a sustained interaction between NLRP3 and ASC in the endoplasmic reticulum. These data are suggestive of a role for SHP in controlling NLRP3 inflammasome activation through a mechanism involving interaction with NLRP3 and maintenance of mitochondrial homeostasis.


Assuntos
Proteínas de Transporte/metabolismo , Inflamassomos/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Adaptadoras de Sinalização CARD , Caspase 1/metabolismo , Retículo Endoplasmático/metabolismo , Ativação Enzimática , Células HEK293 , Homeostase , Humanos , Interleucina-1beta/metabolismo , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ligação Proteica , Transporte Proteico , Receptores Citoplasmáticos e Nucleares/deficiência
15.
Sci Rep ; 4: 5117, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24873950

RESUMO

Cytometric studies utilizing flow cytometry or multi-well culture plate fluorometry are often limited by a deficit in temporal resolution and a lack of single cell consideration. Unfortunately, many cellular processes, including signaling, motility, and molecular transport, occur transiently over relatively short periods of time and at different magnitudes between cells. Here we demonstrate the multitrap nanophysiometer (MTNP), a low-volume microfluidic platform housing an array of cell traps, as an effective tool that can be used to study individual unattached cells over time with precise control over the intercellular microenvironment. We show how the MTNP platform can be used for hematologic cancer cell characterization by measuring single T cell levels of CRAC channel modulation, non-translational motility, and ABC-transporter inhibition via a calcein-AM efflux assay. The transporter data indicate that Jurkat T cells exposed to indomethacin continue to accumulate fluorescent calcein for over 60 minutes after calcein-AM is removed from the extracellular space.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Separação Celular/instrumentação , Citometria de Fluxo/instrumentação , Leucemia de Células T/metabolismo , Técnicas Analíticas Microfluídicas/instrumentação , Análise Serial de Tecidos/instrumentação , Animais , Desenho de Equipamento , Análise de Falha de Equipamento , Fluoresceínas/análise , Humanos , Células Jurkat , Leucemia de Células T/patologia , Nanotecnologia/instrumentação , Pinças Ópticas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Nat Commun ; 5: 2958, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24389582

RESUMO

The redox-dependent inhibition of thioredoxin (TRX) by thioredoxin-interacting protein (TXNIP) plays a pivotal role in various cancers and metabolic syndromes. However, the molecular mechanism of this regulation is largely unknown. Here, we present the crystal structure of the TRX-TXNIP complex and demonstrate that the inhibition of TRX by TXNIP is mediated by an intermolecular disulphide interaction resulting from a novel disulphide bond-switching mechanism. Upon binding to TRX, TXNIP undergoes a structural rearrangement that involves switching of a head-to-tail interprotomer Cys63-Cys247 disulphide between TXNIP molecules to an interdomain Cys63-Cys190 disulphide, and the formation of a de novo intermolecular TXNIP Cys247-TRX Cys32 disulphide. This disulphide-switching event unexpectedly results in a domain arrangement of TXNIP that is entirely different from those of other arrestin family proteins. We further show that the intermolecular disulphide bond between TRX and TXNIP dissociates in the presence of high concentrations of reactive oxygen species. This study provides insight into TRX and TXNIP-dependent cellular regulation.


Assuntos
Proteínas de Transporte/metabolismo , Dissulfetos/metabolismo , Oxirredução , Espécies Reativas de Oxigênio , Tiorredoxinas/metabolismo , Cristalografia por Raios X , Humanos , Modelos Moleculares , Estrutura Terciária de Proteína
17.
Singapore Med J ; 52(4): 246-51, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21552784

RESUMO

INTRODUCTION: The Singapore Polyposis Registry (SPR) was established in 1989 at the Singapore General Hospital. This initiative was aimed at providing a central registry service to facilitate identification, surveillance and management of families and individuals at high risk of colorectal cancer. The aim of the present study was to provide a comprehensive review of all patients with familial adenomatous polyposis (FAP) syndrome in the SPR. METHODS: All patients diagnosed with FAP in 1989-2009 were analysed. Data was extracted from a prospectively collected database. RESULTS: 122 patients from 88 families were analysed. The median age of this cohort was 29 (range 10-68) years. 97 percent of the cases were FAP and 3 percent were attenuated FAP. 92 patients tested positive for adenomatous polyposis coli gene. 42 percent of patients were diagnosed with colorectal cancer, of which 78 percent were diagnosed at an advanced stage. 73 percent of patients underwent restorative proctocolectomy and 21 percent had total colectomy. The median age at operation was 30 years. At median follow-up of 98 months, ten-year overall survival was 75.6 percent (95 percent confidence interval 67.0-84.2) and the median age at death was 40 years. For cancer cases, the overall recurrence was 13.5 percent. Recurrence and disease-free survival were not significant for the type of surgery performed (p-value is 0.486). CONCLUSION: The SPR plays an important and integral part in counselling patients and families with FAP. Improved surveillance programmes may be required to detect the development of cancers in these patients at an earlier stage.


Assuntos
Polipose Adenomatosa do Colo/terapia , Polipose Adenomatosa do Colo/diagnóstico , Adolescente , Adulto , Idoso , Criança , Colectomia/métodos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/terapia , Bases de Dados Factuais , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Sistema de Registros , Singapura , Resultado do Tratamento
18.
Colorectal Dis ; 10(2): 165-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17506796

RESUMO

OBJECTIVE: High anterior resection (HAR) for colorectal cancer is traditionally performed with routine mobilization of the splenic flexure. This is a retrospective review of mortality and morbidity following HAR in which the splenic flexure has been preserved. METHOD: From a prospective database, all patients who had undergone elective HAR for colorectal cancer between 1999 and 2005 were identified. Morbidity, mortality, pathology and survival data for patients having HAR with and without splenic flexure mobilization were analysed. RESULTS: A total of 707 patients were identified. Five hundred and thirty-one had HAR with preservation of the splenic flexure. In these patients outcome was: anastomotic leak (0.4%), wound infection (3.6%), anastomotic stricture (0.4%) and 30-day mortality (0.9%). No statistical significant difference was found for postoperative morbidity (P = 0.1926), 30-day mortality (P =0.3285), lymph node harvest (P = 0.2127) or survival (P = 0.1457) compared with patients in whom the splenic flexure was mobilized. Longitudinal resection margins were greater following HAR with splenic flexure mobilization (P < 0.0001). CONCLUSION: No morbidity, oncological or survival disadvantage in performing splenic flexure preserving HAR was found.


Assuntos
Colectomia/métodos , Neoplasias Colorretais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Colo Transverso/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Estatísticas não Paramétricas , Resultado do Tratamento
19.
J Neurochem ; 99(5): 1338-50, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17064360

RESUMO

Activity-dependent plasticity in nociceptive pathways has been implicated in pathomechanisms of chronic pain syndromes. Calcitonin gene-related peptide (CGRP), which is expressed by trigeminal nociceptors, has recently been identified as a key player in the mechanism of migraine headaches. Here we show that CGRP is coexpressed with brain-derived neurotrophic factor (BDNF) in a large subset of adult rat trigeminal ganglion neurons in vivo. Using ELISA in situ, we show that CGRP (1-1000 nM) potently enhances BDNF release from cultured trigeminal neurons. The effect of CGRP is dose-dependent and abolished by pretreatment with CGRP receptor antagonist, CGRP(8-37). Intriguingly, CGRP-mediated BDNF release, unlike BDNF release evoked by physiological patterns of electrical stimulation, is independent of extracellular calcium. Depletion of intracellular calcium stores with thapsigargin blocks the CGRP-mediated BDNF release. Using transmission electron microscopy, our study also shows that BDNF-immunoreactivity is present in dense core vesicles of unmyelinated axons and axon terminals in the subnucleus caudalis of the spinal trigeminal nucleus, the primary central target of trigeminal nociceptors. Together, these results reveal a previously unknown role for CGRP in regulating BDNF availability, and point to BDNF as a candidate mediator of trigeminal nociceptive plasticity.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/fisiologia , Neurônios Aferentes/metabolismo , Nociceptores/metabolismo , Dor/metabolismo , Gânglio Trigeminal/metabolismo , Animais , Animais Recém-Nascidos , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Estimulação Elétrica , Masculino , Microscopia Imunoeletrônica , Transtornos de Enxaqueca/metabolismo , Transtornos de Enxaqueca/fisiopatologia , Plasticidade Neuronal/fisiologia , Neurônios Aferentes/efeitos dos fármacos , Neurônios Aferentes/ultraestrutura , Dor/induzido quimicamente , Dor/fisiopatologia , Fragmentos de Peptídeos/farmacologia , Terminações Pré-Sinápticas/metabolismo , Terminações Pré-Sinápticas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Núcleo Inferior Caudal do Nervo Trigêmeo/metabolismo , Núcleo Inferior Caudal do Nervo Trigêmeo/ultraestrutura , Gânglio Trigeminal/fisiopatologia , Gânglio Trigeminal/ultraestrutura
20.
Vis Neurosci ; 22(5): 615-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16332272

RESUMO

Effects of anesthesia on the blood glucose of C57/BL6J mice were evaluated under conditions commonly used for testing retinal sensitivity with electroretinographic (ERG) recordings. We evaluated the effects of four anesthetics: nembutal (50 mg/kg), pentothal (100 mg/kg), avertin (240 mg/kg), and ketamine/xylazine (100 mg/kg) using saline as control. We measured blood glucose (BG) levels from tail vein blood before and 15 and 60 min following intraperitoneal injections. Fifteen minutes postinjection, all four anesthetics and saline elevated BG with ketamine/xylazine and avertin having substantially greater effects than nembutal, pentothal, and saline. Only the effects of ketamine/xylazine and avertin persisted throughout the test period. Sixty minutes after injecting ketamine/xylazine BG remained elevated at 400 +/- 42 mg/dl, a 167% increase over preinjection levels. Sixty minutes after injecting avertin BG was 288 +/- 10 mg/dl, a 59% increase over preinjection levels. No sustained elevation in BG was detected 60 min following injection of nembutal, pentothal, or saline. Because BG can affect the amplitude of the ERG, caution should be exercised in the use of ketamine/xylazine or avertin. The choice of anesthesia may also be important in diabetes and metabolism research where changes in blood glucose could impact physiological processes.


Assuntos
Anestesia , Anestésicos Intravenosos , Hiperglicemia/induzido quimicamente , Animais , Glicemia/metabolismo , Temperatura Corporal/efeitos dos fármacos , Eletrorretinografia/efeitos dos fármacos , Feminino , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos C57BL
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