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1.
J Air Waste Manag Assoc ; 65(2): 206-17, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25947056

RESUMO

This study evaluates the performance of AERMOD, the current U.S. Environmental Protection Agency (EPA) regulatory model, in simulating particulate matter (PM10 and PM2.5) dispersion from a poultry pullet facility. At the source, the daily mean PM10 and PM2.5 concentrations with strong diurnal patterns were estimated to be 436.01 ± 166.77 µg m⁻³ and 291.09 ± 105.81 µg m⁻³, respectively. This corresponded to daily mean emission rates of PM10 and PM2.5 as 0.067-0.073 g sec⁻¹ and 0.044-0.047 g sec⁻¹,respectively. The modeled hourly PM concentration showed acceptable accuracy relative to the measured PM concentrations downwind of the source. Increasing the averaging period from hourly to daily resulted in improved prediction. The simulations revealed that PM concentrations at and beyond the property line of the poultry facility were within the National Ambient Air Quality Standards. This study suggested that AERMOD is effective in predicting and assessing the impacts of PM downwind of poultry facilities.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Modelos Teóricos , Tamanho da Partícula , Material Particulado/análise , Criação de Animais Domésticos , Animais , Ohio , Aves Domésticas , Estados Unidos , United States Environmental Protection Agency
2.
Alcohol ; 117: 43-54, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38537764

RESUMO

The relationship between pain and alcohol use disorder (AUD) is complex and bidirectional. The current study examines risk factors for pain in a large comprehensively phenotyped sample including individuals from across the spectrum of alcohol use and misuse. Participants (n = 1101) were drawn from the National Institute on Alcohol Abuse and Alcoholism Natural History Protocol and included treatment-seeking AUD inpatients (AUD+Tx, n = 369), individuals with AUD not seeking treatment (AUD+, n = 161), and individuals without AUD (AUD-, n = 571). General linear models were utilized to test the effects of AUD status, history of childhood trauma exposure, perceived stress, and psychological comorbidity on daily percent time in pain, as well as change in daily percent time in pain across the inpatient stay in AUD+Tx individuals. Overall, 60.2% individuals reported any pain, with a significantly higher prevalence in the AUD+Tx group (82.1%) compared to the AUD+ (56.5%) and AUD- (47.1%) groups. Daily percent time in pain was also highest in the AUD+Tx group (30.2%) and was further increased in those with a history of childhood abuse and comorbid posttraumatic stress disorder (PTSD). Years of heavy drinking and craving were also associated with increased percent time in pain in the AUD+Tx group. Percent time in pain decreased following acute withdrawal in the AUD+Tx group but plateaued around 25% just prior to discharge. Individuals seeking inpatient treatment for AUD, especially those with a history of childhood trauma and/or comorbid PTSD, report greater percent time in pain compared to those not seeking treatment and those without AUD. The prolonged experience of pain in abstinent AUD inpatients after the resolution of acute withdrawal may signal the early stages of protracted withdrawal. Integrative treatments targeting pain and other symptoms of protracted withdrawal may be effective in improving overall function in people with severe AUD.


Assuntos
Alcoolismo , Comorbidade , Dor , Estresse Psicológico , Humanos , Feminino , Masculino , Alcoolismo/epidemiologia , Alcoolismo/psicologia , Adulto , Pessoa de Meia-Idade , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia , Dor/psicologia , Dor/epidemiologia , Experiências Adversas da Infância/psicologia , Fatores de Risco
3.
Rev Sci Instrum ; 79(5): 054701, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18513082

RESUMO

In this paper, a ramp generator with programmable slope is presented. It consists of a high voltage step generator, followed by integrator. The capacitor and inductor in the integrator are designed such that they can be varied by a microcontroller. This circuit generates two bipolar ramps with fastest speed <1 ns and provides continuous speed variation from 6 to 30 ns for a ramp of 500 V. This is being developed as a part of automated streak camera for deflection of electron beam.

4.
Clin Cancer Res ; 5(12): 4105-10, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10632347

RESUMO

Membrane type 1-matrix metalloproteinase (MT1-MMP) is a known activator of latent MMP-2 (pro-MMP-2), and increased MMP-2 expression has been associated with tumor aggressiveness in prostate cancer. However, expression of MT1-MMP in human prostate tissue has not been described. We investigated the expression and immunolocalization of MT1-MMP and MMP-2 in the epithelial components of benign prostate epithelium, high-grade prostatic intraepithelial neoplasia (HGPIN), and prostate cancer. Tissue sections from the peripheral zone of 50 prostates (radical prostatectomy specimens) were chosen based on their containing benign glands, HGPIN, and prostate cancer glands. All 50 sections were immunostained for MT1-MMP and MMP-2 and were evaluated for staining pattern, uniformity, and intensity. Western blotting and gelatin zymography were done to confirm expression of MT1-MMP and activity of MMP-2, respectively. Comparisons were made between benign epithelium, HGPIN, and cancer. In benign glands, basal cells (BCs) uniformly stained intensely for MT1-MMP, whereas secretory cells (SCs) were rarely positive (P < 0.0001). Conversely in HGPIN, SCs showed consistent cytoplasmic staining (P < 0.0001). In cancer cells, staining was heterogeneous and varied from no staining to very intense staining in select glands. MMP-2 in normal tissue stained both BCs and the apical region of SCs, whereas in HGPIN, staining was observed in the SC in a predominantly cytoplasmic pattern. Similar to MT1-MMP, staining in cancer tissue for MMP-2 was heterogeneous; however, there was a significant association between the pattern of MMP-2 and MT1-MMP staining within the epithelial components of the cancer glands in individual specimens (P < 0.001). Finally, MMP-2 and MT1-MMP were confirmed to be expressed in the prostate tissues by gelatin zymography and Western blotting. In conclusion, we found that consistent changes in localization and intracellular distribution of MMP-2 and MT1-MMP were associated with the transition from benign prostate epithelium to HGPIN, suggesting that regulation of these enzymes is altered during the earliest stages of prostate cancer.


Assuntos
Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinases da Matriz/metabolismo , Metaloendopeptidases , Próstata/enzimologia , Neoplasia Prostática Intraepitelial/enzimologia , Neoplasias da Próstata/enzimologia , Adulto , Idoso , Sequência de Aminoácidos , Western Blotting , Epitélio/enzimologia , Humanos , Imuno-Histoquímica , Masculino , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinases da Matriz/biossíntese , Metaloproteinases da Matriz Associadas à Membrana , Pessoa de Meia-Idade , Dados de Sequência Molecular , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , Coloração e Rotulagem
5.
Carbohydr Polym ; 132: 481-9, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26256373

RESUMO

Polypyrrole nanotubes-chitosan (PPy-NTs:chitosan) nanocomposite films have been synthesized with varying concentration of polypyrrole nanotubes (PPy-NTs) and their physical and biological properties have been investigated. Scanning electron microscopy (SEM) micrographs exhibit the increase in surface roughness of the nanocomposite films with increasing concentration of PPy-NTs. Enhancement in hydrophilicity of the nanocomposite films has been observed after surface functionalization with glutaraldehyde which is attributed to increase in surface energy due to the incorporation of polar groups on the films surface. The increasing amount of PPy-NTs in the nanocomposite leads to an increase in haemolysis activity, while the treatment with glutaraldehyde results in the decrease in haemolysis activity giving rise to higher biocompatibility. Urease immobilization in glutaraldehyde treated films exhibits higher enzymatic activity as compared to that of the untreated films, which is attributed to the enhancement in hydrophilicity and biocompatibility of the PPy-NTs:chitosan nanocomposites after functionalization with glutaraldehyde.


Assuntos
Quitosana/química , Nanocompostos/química , Nanotubos/química , Polímeros/química , Pirróis/química , Animais , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Cinética , Nanocompostos/toxicidade , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Urease/química , Urease/metabolismo , Difração de Raios X
6.
Mater Sci Eng C Mater Biol Appl ; 54: 8-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26046261

RESUMO

Polypyrrole nanotube-silver nanoparticle nanocomposites (PPy-NTs:Ag-NPs) have been synthesized by in-situ reduction of silver nitrate (AgNO3) to suppress the agglomeration of Ag-NPs. The morphology and chemical structure of the nanocomposites have been studied by HRTEM, SEM, XRD, FTIR and UV-vis spectroscopy. The average diameter of the polypyrrole nanotubes (PPy-NTs) is measured to be 130.59±5.5 nm with their length in the micrometer range, while the silver nanoparticles (Ag-NPs) exhibit spherical shape with an average diameter of 23.12±3.23 nm. In-vitro blood compatibility of the nanocomposites has been carried out via hemolysis assay. Antimicrobial activity of the nanocomposites has been investigated with Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria. The results depict that the hemolysis and antimicrobial activities of the nanocomposites increase with increasing Ag-NP concentration that can be controlled by the AgNO3 precursor concentration in the in-situ process.


Assuntos
Antibacterianos/farmacologia , Hemólise , Nanopartículas Metálicas/química , Nanotubos/química , Polímeros/farmacologia , Pirróis/farmacologia , Prata/química , Animais , Antibacterianos/química , Eritrócitos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanocompostos/química , Tamanho da Partícula , Polímeros/química , Pirróis/química , Nitrato de Prata , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos
7.
Antiviral Res ; 15(1): 67-76, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1852150

RESUMO

HSV-1 multiplication rates have been shown to vary in different tissues and the rate of multiplication may correlate with susceptibility to antiviral chemotherapy. Herpetic stromal keratitis is a necrotizing condition refractive to antiviral therapy and this lack of antiviral efficacy in stromal disease may be the result of very low rates of viral replication in the corneal stromal keratocytes. In this study, we investigated the efficacy of antiviral drugs in an in vitro system in which the virus multiplication rate is slow. In this system, the reduced rate of virus multiplication is achieved by a reduction in the incubation temperature. Vero cells were infected at one of several multiplicities of infection with McKrae strain HSV-1 and incubated for 24, 48, or 72 h at 26 or 36.5 degrees C in the presence or absence of trifluridine (50 micrograms/ml) or acyclovir (20 micrograms/ml). Both drugs suppressed viral replication at 36.5 degrees C. However, under some specific sets of conditions, trifluridine was not effective in suppressing viral replication in cells incubated at 26 degrees C. At this temperature, viral replication and cell metabolism are slowed to a pace which may be similar to that which occurs in corneal stromal keratocytes in vivo. Acyclovir significantly reduced HSV-1 replication under all conditions at 26 degrees C, indicating that the antiviral activity of this compound is effective in cells whose metabolic rate is slow and in which viral replication is taking place slowly.


Assuntos
Aciclovir/farmacologia , Herpes Simples/tratamento farmacológico , Simplexvirus/efeitos dos fármacos , Trifluridina/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Simplexvirus/crescimento & desenvolvimento , Células Vero/microbiologia , Ensaio de Placa Viral
8.
Urology ; 51(4): 638-9, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9586621

RESUMO

Intractable, therapy-resistant priapism in a patient with sickle cell disease is presented. The patient was managed with insertion of an inflatable penile prosthesis. He consequently maintained potency and remains free of priapitic episodes. To our knowledge, immediate penile prosthesis insertion for management of priapism has not been reported. We discuss the indications and advantages of this approach and review the current literature.


Assuntos
Anemia Falciforme/complicações , Prótese de Pênis , Priapismo/complicações , Priapismo/cirurgia , Adulto , Humanos , Masculino
9.
Urology ; 55(6): 899-903, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10840105

RESUMO

OBJECTIVES: Although the rate of positive surgical margins is higher in African-American men (AAM) than in white men (WM), the impact of this difference on survival is not clear. Furthermore, it is unknown whether there are racial differences in the distribution of the positive surgical margins after radical retropubic prostatectomy (RRP). We investigated the differences between AAM and WM in terms of the site and multifocality of the positive surgical margins and their effect on disease-free survival (DFS) following RRP. METHODS: Between January 1991 and December 1995, 493 patients (288 WM and 205 AAM) were treated with RRP as monotherapy. Positive surgical margins were observed in 179 patients (86 WM and 93 AAM). Patients were divided in two groups: group 1 = WM and group 2 = AAM. The incidence and location of the positive surgical margins and their correlation with DFS were determined and compared. RESULTS: Overall, AAM had a higher rate of positive surgical margins than WM (48% versus 33%, respectively, P = 0.001). There was no significant difference in the frequency of multifocality of the positive margins (P = 0.4). Positive surgical margins were located significantly more often at the base in AAM (P = 0.015); however, the location of the positive surgical margins did not impact on DFS between groups. In those with multifocal positive surgical margins, AAM had a worse DFS compared with WM (P = 0.03). CONCLUSIONS: Race is an independent prognostic factor for DFS in patients with positive surgical margins. There were no differences in DFS between WM and AAM based on the margin location. In WM, prognostic factors for DFS in those with positive surgical margins were preoperative serum prostate-specific antigen, Gleason score, and pathologic stage. Conversely, in AAM none of these parameters were significant predictors of failure.


Assuntos
Negro ou Afro-Americano , Prostatectomia/estatística & dados numéricos , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , População Branca , Idoso , Intervalo Livre de Doença , Humanos , Masculino , Pessoa de Meia-Idade
10.
Urol Clin North Am ; 28(3): 545-53, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11590813

RESUMO

Although technically challenging, salvage prostatectomy for radiorecurrent prostate cancer is an effective option in carefully selected patients and offers the best chance for cure and long-term survival. Alternatively, cystoprostatectomy may be indicated in some patients who have a small capacity fibrotic bladder or intractable voiding symptoms related to radiation cystitis. Good long-term results can be expected in this patient group; however, exenterative surgery in patients with locally advanced disease is associated with comparably inferior results and should not be advocated. If cystectomy is necessary, orthotopic urinary diversion can be performed safely in young motivated patients who wish to maintain a better quality of life with associated morbidity. Although the higher rate of incontinence and impotence after salvage procedures may detract from the quality of life, the impact of these long-term complications on the patient's overall well-being is less than previously believed, and most patients are satisfied with their treatment outcome and adjust well to the circumstances, accepting some increased degree of morbidity. This observation emphasizes the value of careful preoperative counseling and the discussion of treatment options and outcomes, which also should incorporate quality of life issues.


Assuntos
Prostatectomia/métodos , Neoplasias da Próstata/cirurgia , Humanos , Masculino , Seleção de Pacientes , Complicações Pós-Operatórias/epidemiologia , Prognóstico , Prostatectomia/efeitos adversos , Neoplasias da Próstata/radioterapia , Qualidade de Vida , Falha de Tratamento
11.
Urol Clin North Am ; 28(3): 639-53, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11590819

RESUMO

With improved surgical technique and perioperative care, the intraoperative and early postoperative complications of radical prostatectomy have decreased over the last 2 decades. Incontinence and impotence are two of the most significant long-term complications related to this procedure. Although the wide range of incontinence and impotence rates reported has been attributed to multiple factors, including the method of data collection and patient selection, it is apparent that the surgeon's experience is a significant factor, and that lower long-term morbidity can be expected from centers with more experience with radical prostatectomies. The impact of long-term complications, including urinary and sexual dysfunction, on the quality of life may be less than previously reported and should be discussed with patients.


Assuntos
Complicações Intraoperatórias/etiologia , Complicações Pós-Operatórias/etiologia , Prostatectomia/efeitos adversos , Neoplasias da Próstata/cirurgia , Disfunção Erétil/epidemiologia , Disfunção Erétil/etiologia , Humanos , Complicações Intraoperatórias/epidemiologia , Masculino , Complicações Pós-Operatórias/epidemiologia , Cuidados Pré-Operatórios , Prostatectomia/métodos , Qualidade de Vida , Reto/lesões , Fatores de Tempo , Traumatismos do Sistema Nervoso , Ureter/lesões , Incontinência Urinária/epidemiologia , Incontinência Urinária/etiologia
12.
Rev Sci Instrum ; 85(6): 064704, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24985834

RESUMO

A high voltage pulse generator with variable amplitude (100-3000 V) and duration (100-2000 µs) has been designed and developed. The variable duration pulse has been generated by adopting a simple and novel technique of varying the turn off delay time of a high voltage Metal Oxide Semiconductor Field Effect Transistor (MOSFET) based switch by varying external gate resistance. The pulse amplitude is made variable by adjusting biasing supply of the high voltage switch. The high voltage switch has been developed using a MOSFET based stack of 3 kV rating with switching time of 7 ns.

13.
Eur J Pain ; 18(2): 223-37, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23857727

RESUMO

BACKGROUND: The function of brain networks can be changed in a maladaptive manner in response to chronic neuropathic pain. Analgesics can reduce pain by acting on such networks via direct or indirect (peripheral or spinal) mechanisms. This investigation aimed to map gabapentin's pharmacodynamics (PD) in the rodent brain following induction of neuropathic pain in order to further understand its PD profile. METHODS: Pharmacological magnetic resonance imaging (phMRI) and a novel functional connectivity analysis procedure were performed following vehicle or gabapentin treatment in the rat spinal nerve ligation (SNL) model of neuropathic pain as well as sham animals. RESULTS: phMRI performed in SNL animals revealed robust gabapentin-induced responses throughout the hippocampal formation, yet significant (p < 0.05, corrected for multiple comparisons) responses were also measured in other limbic structures and the sensorimotor system. In comparison, sham animals displayed weaker and less widespread phMRI signal changes subsequent to gabapentin treatment. Next, communities of networks possessing strong functional connectivity were elucidated in vehicle-treated SNL and sham animals. We observed that SNL and sham animals possessed distinct functional connectivity signatures. When measuring how gabapentin altered the behaviour of the discovered networks, a decrease in functional connectivity driven by gabapentin was not only observed, but the magnitude of this PD effect was greater in SNL animals. CONCLUSIONS: Using phMRI and functional connectivity analysis approaches, the PD effects of gabapentin in a preclinical neuropathic pain state were characterized. Furthermore, the current results offer insights on which brain systems gabapentin directly or indirectly acts upon.


Assuntos
Aminas/farmacologia , Analgésicos/farmacologia , Ácidos Cicloexanocarboxílicos/farmacologia , Neuralgia/tratamento farmacológico , Nervos Espinhais/efeitos dos fármacos , Ácido gama-Aminobutírico/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Gabapentina , Masculino , Neuralgia/fisiopatologia , Ratos , Ratos Sprague-Dawley , Nervos Espinhais/fisiopatologia
14.
Mater Sci Eng C Mater Biol Appl ; 33(8): 4900-4, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24094203

RESUMO

In this work, the effect of 100 MeV Si(9+) ion beam with four different fluences on antioxidant and structural properties of polypyrrole nanotubes has been investigated. Polypyrrole nanotubes have been synthesized by reactive self degrade template method. Fragmentation of the polypyrrole nanotubes at higher fluence is revealed from the high resolution transmission electron micrograph (HRTEM) and X-ray diffraction (XRD) results. The decrease in characteristics band of polypyrrole in Fourier transmission of infrared spectra (FTIR) spectra suggests the main chain scission of polypyrrole during irradiation. The free radical scavenging activity of pristine and irradiated samples are evaluated by using α, α-diphenyl-ß-picrylhydrazyl (DPPH) assay. The decline of the UV-visible absorbance at 516 nm suggests the neutralization of DPPH free radicals through the reaction with polypyrrole. Significant increase in antioxidant activity of polypyrrole nanotubes is observed with increase in ion fluence.


Assuntos
Antioxidantes/química , Nanotubos/química , Polímeros/química , Pirróis/química , Radiação Ionizante , Silício/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
15.
Rev Sci Instrum ; 83(2): 024709, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22380115

RESUMO

A high-voltage pulse-slicer unit with variable pulse duration has been developed and integrated with a 7 MeV linear electron accelerator (LINAC) for pulse radiolysis investigation. The pulse-slicer unit provides switching voltage from 1 kV to 10 kV with rise time better than 5 ns. Two MOSFET based 10 kV switches were configured in differential mode to get variable duration pulses. The high-voltage pulse has been applied to the deflecting plates of the LINAC for slicing of electron beam of 2 µs duration. The duration of the electron beam has been varied from 30 ns to 2 µs with the optimized pulse amplitude of 7 kV to get corresponding radiation doses from 6 Gy to 167 Gy.

16.
Neuroscience ; 202: 446-53, 2012 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-22119061

RESUMO

Several neuroimaging studies have revealed that the brains of schizophrenic patients exhibit abnormalities in white matter pathways. Using magnetic resonance imaging (MRI) methods, such as T2-weighted imaging and diffusion tensor imaging (DTI), it is possible to objectively quantify white matter structural properties in patients as well as the pharmacological effect on white matter. In the preclinical domain, these strategies, however, have been hindered by a lack of in vivo imaging assays. One preclinical approach that has been used to pharmacologically challenge the integrity of the white matter is the chronic administration of the copper chelator, cuprizone. In the present study, C57BL/6 mice were given 0.2% cuprizone in their diet for five weeks with or without the antipsychotic drug, quetiapine (10 mg/kg). In accordance with previous studies, myelin breakdown in cuprizone-exposed mice was measured by using T2-weighted MRI and DTI. Here, we demonstrate that cuprizone-induced white matter changes were attenuated by quetiapine treatment. These MRI-based results and trends were confirmed by histological and immunohistochemistry measures. This study suggests that the cuprizone-exposed C57BL/6 mouse is a potential animal model to investigate the impact of treatments on white matter abnormalities in schizophrenia.


Assuntos
Quelantes , Cuprizona , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/patologia , Animais , Antipsicóticos/farmacologia , Interpretação Estatística de Dados , Dibenzotiazepinas/farmacologia , Imagem de Tensor de Difusão , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Fumarato de Quetiapina
17.
Rev Sci Instrum ; 81(8): 085106, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20815627

RESUMO

A microcontroller based system has been developed for automation of the S-20 optical streak camera, which is used as a diagnostic tool to measure ultrafast light phenomenon. An 8 bit MCS family microcontroller is employed to generate all control signals for the streak camera. All biasing voltages required for various electrodes of the tubes are generated using dc-to-dc converters. A high voltage ramp signal is generated through a step generator unit followed by an integrator circuit and is applied to the camera's deflecting plates. The slope of the ramp can be changed by varying values of the capacitor and inductor. A programmable digital delay generator has been developed for synchronization of ramp signal with the optical signal. An independent hardwired interlock circuit has been developed for machine safety. A LABVIEW based graphical user interface has been developed which enables the user to program the settings of the camera and capture the image. The image is displayed with intensity profiles along horizontal and vertical axes. The streak camera was calibrated using nanosecond and femtosecond lasers.

18.
Paediatr Anaesth ; 16(2): 192-4, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16430419

RESUMO

We report a case of hyponatremic seizures in a 7-year old boy with spina bifida following cystoscopy and suprapubic catheter placement. Immediate postoperative cystogram and pelvic computed tomogram (CT) after the development of seizures demonstrated a fluid collection from the suprapubic catheter site into the anterior abdominal wall. The subsequent reabsorption of free water from the fluid collection, with the contribution of postoperative hypotonic intravenous fluid administration and possible transient inappropriate antidiuretic hormone (ADH) secretion resulted in acute dilutional hyponatremia and consequent seizures. Strategies to prevent hyponatremia in children during urological procedures, with emphasis on the importance of reserving free water as the irrigation fluid are discussed.


Assuntos
Cateterismo/efeitos adversos , Cistoscopia/métodos , Hiponatremia/complicações , Complicações Pós-Operatórias/etiologia , Convulsões/etiologia , Parede Abdominal , Anticonvulsivantes/administração & dosagem , Criança , Diuréticos/administração & dosagem , Furosemida/administração & dosagem , Glucose/administração & dosagem , Glucose/efeitos adversos , Humanos , Hiponatremia/sangue , Hiponatremia/tratamento farmacológico , Síndrome de Secreção Inadequada de HAD/etiologia , Lorazepam/administração & dosagem , Masculino , Pelve/diagnóstico por imagem , Complicações Pós-Operatórias/sangue , Convulsões/tratamento farmacológico , Cloreto de Sódio/administração & dosagem , Disrafismo Espinal/complicações , Irrigação Terapêutica/efeitos adversos , Tomografia Computadorizada por Raios X/métodos , Equilíbrio Hidroeletrolítico
19.
J Bacteriol ; 95(3): 771-4, 1968 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-5651324

RESUMO

A soil amoeba, Hartmannella glebae, could grow on a variety of gram-positive and gram-negative bacteria, although the rate of growth was faster in the presence of gram-negative bacteria. The amoeba, however, could not use yeasts, molds, or a green alga as a nutritional source. The extract prepared from amoebae grown in the presence of Aerobacter aerogenes and Alcaligenes faecalis could lyse intact cells and cell walls of many gram-positive bacteria at different rates. The spectrum of lytic activity was similar to that of egg-white lysozyme, with the exception that several species and strains of Bacillus, Micrococcus, and Staphylococcus were resistant to lysozyme and susceptible to the extract. The gram-negative bacteria tested were resistant.


Assuntos
Bacteriólise , Eucariotos/crescimento & desenvolvimento , Microbiologia do Solo , Bactérias/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Eucariotos/enzimologia , Eucariotos/metabolismo , Fungos , Hidrolases/farmacologia , Muramidase/farmacologia , Leveduras
20.
Appl Environ Microbiol ; 38(3): 373-8, 1979 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-533270

RESUMO

Two bacteriolytic enzymes were produced when Hartmanella glebae was grown in the presence of both Enterobacter aerogenes and Alcaligenes faecalis. The identification of enzyme I as N-acetylmuramidase was reported earlier. Enzyme II was purified by gel filtration on a Bio-Gel A column. A recovery of 68.76% with 72.3-fold purification was obtained. It was found that 5 and 10 mM MgCl2 significantly increased the bacteriolytic activity. It is a basic protein. The cell walls of Micrococcus lysodeikticus were lysed by the enzyme, and the products of digestion were purified by Amberlite CG-120 and Sephadex G-15 chromatography to facilitate the detection of amino sugars. After reduction of the oligosaccharides with sodium borohydride and acid hydrolysis, the amino sugars were identified by paper chromatography. It was found that enzyme II cleaved the glycosidic bond between N-acetylmuramic and and N-acetylglucosamine of the peptidoglycan moiety of the cell walls. Thus, the enzyme was identified as endo-beta-N-acetylmuramidase.


Assuntos
Hartmannella/enzimologia , Muramidase/metabolismo , Microbiologia do Solo , Animais , Bacteriólise , Parede Celular/metabolismo , Micrococcus/metabolismo , Ácidos Murâmicos/metabolismo , Muramidase/isolamento & purificação , Especificidade por Substrato
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