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1.
Neuropathol Appl Neurobiol ; 47(2): 236-250, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32779246

RESUMO

AIMS: Biomarker-driven therapies have not been developed for infant medulloblastoma (iMB). We sought to robustly sub-classify iMB, and proffer strategies for personalized, risk-adapted therapies. METHODS: We characterized the iMB molecular landscape, including second-generation subtyping, and the associated retrospective clinical experience, using large independent discovery/validation cohorts (n = 387). RESULTS: iMBGrp3 (42%) and iMBSHH (40%) subgroups predominated. iMBGrp3 harboured second-generation subtypes II/III/IV. Subtype II strongly associated with large-cell/anaplastic pathology (LCA; 23%) and MYC amplification (19%), defining a very-high-risk group (0% 10yr overall survival (OS)), which progressed rapidly on all therapies; novel approaches are urgently required. Subtype VII (predominant within iMBGrp4 ) and subtype IV tumours were standard risk (80% OS) using upfront CSI-based therapies; randomized-controlled trials of upfront radiation-sparing and/or second-line radiotherapy should be considered. Seventy-five per cent of iMBSHH showed DN/MBEN histopathology in discovery and validation cohorts (P < 0.0001); central pathology review determined diagnosis of histological variants to WHO standards. In multivariable models, non-DN/MBEN pathology was associated significantly with worse outcomes within iMBSHH . iMBSHH harboured two distinct subtypes (iMBSHH-I/II ). Within the discriminated favourable-risk iMBSHH DN/MBEN patient group, iMBSHH-II had significantly better progression-free survival than iMBSHH-I , offering opportunities for risk-adapted stratification of upfront therapies. Both iMBSHH-I and iMBSHH-II showed notable rescue rates (56% combined post-relapse survival), further supporting delay of irradiation. Survival models and risk factors described were reproducible in independent cohorts, strongly supporting their further investigation and development. CONCLUSIONS: Investigations of large, retrospective cohorts have enabled the comprehensive and robust characterization of molecular heterogeneity within iMB. Novel subtypes are clinically significant and subgroup-dependent survival models highlight opportunities for biomarker-directed therapies.


Assuntos
Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Meduloblastoma/genética , Meduloblastoma/patologia , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Estudos Retrospectivos
2.
Appl Opt ; 55(16): 4285-92, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27411177

RESUMO

The use of a grazing incidence optic to selectively reflect K-shell fluorescence emission and isotope-specific lines from special nuclear materials is a highly desirable nondestructive analysis method for use in reprocessing fuel environments. Preliminary measurements have been performed, and a simulation suite has been developed to give insight into the design of the x ray optics system as a function of the source emission, multilayer coating characteristics, and general experimental configurations. The experimental results are compared to the predictions from our simulation toolkit to illustrate the ray-tracing capability and explore the effect of modified optics in future measurement campaigns.

3.
Rev Sci Instrum ; 86(1): 013110, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25638075

RESUMO

A multilayer-based optic was tested for use as an X-ray diagnostic on a laser-plasma experiment. The multilayer optic was employed to selectively pass X-rays between 55 and 100 keV. An order of magnitude improvement in signal-to-noise ratio is achieved compared to a transmission crystal spectrometer. A multilayer response model, taking into account the source size and spectral content, is constructed and the outlook for application above 500 keV is briefly discussed. LLNL-JRNL-664311.

4.
Community Dent Health ; 31(3): 158-62, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25300150

RESUMO

OBJECTIVE: This study sought to examine oral health beliefs and attitudes, and utilisation of oral health care services among individuals with diabetes and health professionals who serve them in Ghana. BASIC RESEARCH DESIGN: A qualitative study using grounded theory was conducted. CLINICAL SETTING: University of Ghana Dental School at Korle Bu, University of Ghana School of Public Health, National Diabetes Research and Management Centre at Korle Bu, and New York University College of Dentistry. PARTICIPANTS: A convenience sample of 59 patients comprised 7 focus groups conducted in either Twi or English. Seven key informant interviews with healthcare professionals and one spiritual leader were completed. RESULTS: Data from the focus groups and interviews reveal: 1, half of the participants with diabetes have oral manifestations (e.g., bleeding gums) and participants are generally unaware of interrelationship between diabetes and oral health; 2, dental treatment utilisation is minimal and associated almost exclusively with reparative and emergency care; and 3, medical health providers do not acknowledge the interrelationship between oral health and diabetes nor do they incorporate oral health issues into diabetes screening/treatment. CONCLUSION: Oral health knowledge and practices are limited among patients with diabetes in Accra, Ghana. Collaborative efforts for in-service education and training for oral health and medical professionals may be beneficial in serving the oral and general health care needs as well as improving the oral health-related quality of life of Ghanaians with diabetes.


Assuntos
Atitude Frente a Saúde , Diabetes Mellitus Tipo 2/complicações , Saúde Bucal , Adulto , Assistência Odontológica/psicologia , Assistência Odontológica/estatística & dados numéricos , Diabetes Mellitus Tipo 2/prevenção & controle , Diabetes Mellitus Tipo 2/psicologia , Feminino , Grupos Focais , Gana , Hemorragia Gengival/complicações , Gengivite/complicações , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Higiene Bucal , Educação de Pacientes como Assunto , Pesquisa Qualitativa , Qualidade de Vida , Terapias Espirituais
5.
J Bone Joint Surg Br ; 87(10): 1397-401, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16189315

RESUMO

The routine use of surgical drains in total hip arthroplasty remains controversial. They have not been shown to decrease the rate of wound infection significantly and can provide a retrograde route for it. Their use does not reduce the size or incidence of post-operative wound haematomas. This prospective, randomised study was designed to evaluate the role of drains in routine total hip arthroplasty. We investigated 552 patients (577 hips) undergoing unilateral or bilateral total hip arthroplasty who had been randomised to either having a drain for 24 hours or not having a drain. All patients followed standardised pre-, intra-, and post-operative regimes and were independently assessed using the Harris hip score before operation and at six, 18 and 36 months follow-up. The rate of superficial and deep infection was 2.9% and 0.4%, respectively, in the drained group and 4.8% and 0.7%, respectively in the undrained group. One patient in the undrained group had a haematoma which did not require drainage or transfusion. The rate of transfusion after operation in the drained group was significantly higher than for undrained procedures (p < 0.042). The use of a drain did not influence the post-operative levels of haemoglobin, the revision rates, Harris hip scores, the length of hospital stay or the incidence of thromboembolism. We conclude that drains provide no clear advantage at total hip arthroplasty, represent an additional cost, and expose patients to a higher risk of transfusion.


Assuntos
Artroplastia de Quadril , Drenagem , Cuidados Pós-Operatórios/métodos , Idoso , Idoso de 80 Anos ou mais , Transfusão de Sangue , Drenagem/efeitos adversos , Feminino , Hemoglobinas/metabolismo , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Resultado do Tratamento
6.
Arch Physiol Biochem ; 110(1-2): 26-33, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11935397

RESUMO

Serine protease inhibitors (serpins) are a family of structurally related proteins that play key roles in the regulation of proteolytic homeostasis. We have isolated a novel intracellular serpin, termed raPIT5a, from the rat pituitary gland. Northern blot analysis indicated raPIT5a mRNA expression in a range of tissues, including the adrenal gland and the brain. In situ hybridisation histochemistry revealed raPIT5a mRNA expression in specific cell populations in the rat pituitary gland, adrenal gland, and pancreas. Based on sequence similarities to other intracellular serpins, we predicted raPIT5a may inhibit the pro-apoptotic serine protease granzyme B. We confirmed this experimentally by identification of a stable inhibitory complex between granzyme B and raPIT5a. To determine whether granzyme B or granzyme B-related enzymes were expressed in the rat pituitary gland, we performed PCR using primers predicted to amplify granzyme B and two other published granzyme sequences. We identified rat natural killer protease-1 (RNKP-1), the rat homologue of granzyme B, and a novel putative serine protease highly similar to granzyme-like protein III (GLP III), which we termed GLP IIIa. These data suggest raPIT5a may regulate apoptosis in the pituitary by inhibition of granzyme B or GLP IIIa, or members of the caspase enzyme family which have similar substrate specificity. We have also identified expression of a second serpin, called neuroserpin, in pituitary tissue and found that it alters the morphology of the AtT20 corticotrope cell line, presumably through changes in cell adhesion. These results identify new roles for serpins in pituitary cell function.


Assuntos
Neuropeptídeos/genética , Hipófise/metabolismo , Serpinas/genética , Sequência de Aminoácidos , Animais , Northern Blotting , Granzimas , Hibridização In Situ , Dados de Sequência Molecular , Neuropeptídeos/metabolismo , Especificidade de Órgãos , RNA Mensageiro/metabolismo , Ratos , Alinhamento de Sequência , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Serpinas/metabolismo , Neuroserpina
7.
Int J Pharm ; 227(1-2): 139-48, 2001 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-11564548

RESUMO

The dielectric response of a simple, self emulsifying, system, based on a polysorbate and a medium chain length triglyceride, has been investigated as a function of the water content in the range 0 to 80% by weight. The low frequency capacitive dispersions have been characterised in terms of an electrode barrier layer dispersion, and the bulk conductance and capacitance have been quantified. It is shown that the barrier parameters are essentially insensitive to the water content, over concentrations from 2.5 to 75% by weight, and that the magnitude of the bulk emulsion conductance determines the form of the dispersions which can be observed.


Assuntos
Físico-Química , Emulsões , Fenômenos Químicos
8.
Protein Expr Purif ; 22(3): 406-13, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11483002

RESUMO

Neuroserpin (NS) is a serine protease inhibitor (or serpin) that is widely expressed in the developing and adult nervous systems. It has been implicated in the regulation of proteases involved in processes such as synaptic plasticity, neuronal migration, and axogenesis. To aid in the characterization of this new serpin we have established a high-level expression system in Drosophila S2 cells and developed a purification strategy to obtain neuroserpin for functional studies. Suspension cultures of S2-NS cells secreted recombinant neuroserpin into the medium. High-level expression was maintained when the cells were switched to a nonselection serum-free medium for 3-4 days to facilitate protein purification. Recombinant neuroserpin was purified by sequential chromatography on Macroprep ceramic hydroxyapatite, Type I, POROS HQ20, Resource Q, and Superdex 75 HR 10/30 media. Two secreted forms of neuroserpin were observed with molecular weights of approximately 49 and approximately 50 kDa which may represent alternative glycosylation at three putative N-linked glycosylation sites. Amino acid sequence analysis indicated three NH(2)-terminal sequences. The major sequence was generated by cleavage at the Gly(18)-Ala(19) bond consistent with removal of an 18-amino-acid signal peptide. Two further sequences were identified each with one fewer amino acids at the NH(2)-terminus. All three NH(2)-terminal sequences were also identified by mass spectrometric analysis of neuroserpin following trypsin digestion. Mass spectrometry also confirmed the protein had an intact carboxyl terminus while complex formation assays indicated the inhibitor was functionally active. In summary, Drosophila S2 cells offered a nonlytic stable expression system for the continual production of neuroserpin in high-density suspension cultures.


Assuntos
Neuropeptídeos/metabolismo , Inibidores de Serina Proteinase/metabolismo , Serpinas/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Drosophila melanogaster/genética , Humanos , Dados de Sequência Molecular , Peso Molecular , Neuropeptídeos/genética , Neuropeptídeos/isolamento & purificação , Ativadores de Plasminogênio/metabolismo , Ratos , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Inibidores de Serina Proteinase/genética , Inibidores de Serina Proteinase/isolamento & purificação , Serpinas/genética , Serpinas/isolamento & purificação , Neuroserpina
9.
J Bone Joint Surg Br ; 83(8): 1141-4, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11764428

RESUMO

We reviewed 286 consecutive patients with a fracture of a pubic ramus. The overall incidence was 6.9/100,000/year in the total population and 25.6/100,000/year in individuals aged over 60 years. The mean age of the patients was 74.7 years and 24.5% suffered from dementia. Women were affected 4.2 times more often than men. After injury, geriatric rehabilitation was frequently required and although most surviving patients returned to their original place of residence, their level of mobility was often worse. The overall survival rates at one and five years were 86.7% and 45.6%, respectively. Multiple logistic regression analysis showed that age and dementia were the only independent significant factors to be predictive of mortality (p < 0.05). Patients with a fracture of a pubic ramus had a significantly worse survival than an age-matched cohort from the general population (log-rank test, p < 0.001), but this was better than patients with a fracture of the hip during the first year after injury, although their subsequent mortality was higher. Five years after the fracture there was no significant difference in survival between the two groups.


Assuntos
Fraturas Ósseas/epidemiologia , Osso Púbico/lesões , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fraturas Ósseas/mortalidade , Fraturas Ósseas/reabilitação , Humanos , Incidência , Modelos Logísticos , Pessoa de Meia-Idade
10.
Invest Ophthalmol Vis Sci ; 41(11): 3348-59, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11006224

RESUMO

PURPOSE: Interferometric methods have considerable potential for studying the thickness of layers of the human tear film and cornea because of their ability to make noninvasive, accurate, and rapid measurements. However, previous interferometric studies by Prydal and Danjo yielded tear thickness values near 40 and 11 microm, respectively, considerably greater than estimates made by invasive methods of 4 to 8 microm. Using a modified version of Danjo's method, interference effects from the tear film and cornea were studied, with the aim of correlation with known structure and optical properties of the cornea and hence determining the most probable value of tear film thickness. METHODS: Reflectance spectra from the human cornea were measured at normal incidence. These spectra show oscillations whose maxima correspond to constructive interference between light reflected from the air surface and from some deeper surface. The frequency of these spectral oscillations is proportional to the thickness of the layer between the air surface and the second surface. Therefore, Fourier analysis of reflectance spectra can be used to determine the thickness of layers of the tear film and cornea. In the main experiment, 36 low-resolution spectra were obtained from six normal eyes for measuring thickness up to 100 microm. Control experiments included measurements of the time course of thickness changes and high-resolution spectra for measuring thickness up to 1000 microm. RESULTS: For the main experiment, in the thickness range 1 to 100 microm, the strongest peak in the Fourier transform was near 3 microm (range, 1.5-4.7 microm) beneath the air surface. In the range 20 to 100 microm, the strongest peak was near 55 microm (range, 50-59 microm) for all 36 spectra; none were in Prydal's range near 40 microm. This 55-microm peak is consistent with a reflection from the basement membrane of the epithelium. Time course measurements after a blink show that the 3-microm peak is not an artifact. High-resolution spectra gave a peak near 510 microm, corresponding to the complete thickness of the cornea (plus tear film). This peak had a contrast similar to that of the 3-microm peak. CONCLUSIONS: These studies did not confirm Prydal's estimate of approximately 40 microm. Nor were there prominent peaks near Danjo's value of approximately 11 microm, except in cases of probable reflex tears. Because the reflection at the aqueous-mucus boundary would be expected to be weaker than that from the epithelial surface, the 3-microm peak is unlikely to correspond to the aqueous layer (rather than the complete tear film). The proposal that the 3-microm peak corresponds to a reflection from the front of the cornea is supported by the demonstration of a peak of similar contrast from the back of the cornea. Thus, the current evidence consistently supports a value of approximately 3 microm for the thickness of the human precorneal tear film.


Assuntos
Córnea/metabolismo , Técnicas de Diagnóstico Oftalmológico , Síndromes do Olho Seco/metabolismo , Lágrimas/metabolismo , Adulto , Piscadela , Síndromes do Olho Seco/patologia , Proteínas do Olho/análise , Feminino , Humanos , Interferometria , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
11.
Optometry ; 71(4): 239-44, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10974923

RESUMO

BACKGROUND: While the environment of the naturally closed eye substantially challenges the oxygen-dependent processes of the cornea, the presence of a contact lens further exacerbates those stresses. The purposes of this study are: (1) to describe responses of the human cornea under closed eye conditions to a wide range of Dk/t environments as ratios of their corresponding normal, open-eye (physiological) baseline rates; (2) to describe the difference ("hypoxic gap") function that separates those closed-eye responses from parallel responses for the open eye; and (3) to present predictive models for all three (closed-eye, open-eye, and difference) response functions in both graphical and mathematical forms. METHODS: Oxygen uptake rates were measured polarographically: for the normal open eye and after both closed- and open-eye wear of six rigid contact lenses of transmissibilities ranging from 0 to 91 x 10(-9) (cm/sec)(ml O2/ml mmHg). RESULTS: Responses from the closed-eye and open-eye series to those six Dk/t levels were compared both graphically and statistically. Those response series were described by best-fit equations, from which a model for Dk/t effectiveness in meeting corneal oxygen needs under both closed- and open-eye conditions was developed. CONCLUSIONS: Response series for both closed and open eyes were found to be well described by natural log equations (R2 values > 0.99). Statistically, separation of those two series could be demonstrated (p < 0.05) by the Dk/t level of 12.8 x 10(-9) (cm/sec)(ml O2/ml mmHg). While, by the highest Dk/t level observed here of 91 x 10(-9) (cm/sec)(ml O2/ml mmHg), corneal responses for the open eye have already moderated down to just 1.5x the "ideal standard," closed-eye response rates are still averaging 2.7x that baseline. The difference ("hypoxic gap") function remaining between those closed- and open-eye curves appears to be stabilizing in its magnitude by 91 x 10(-9) (cm/sec)(ml O2/ml mmHg) as well.


Assuntos
Lentes de Contato , Córnea/metabolismo , Oxigênio/metabolismo , Adulto , Feminino , Humanos , Masculino , Polimetil Metacrilato , Prognóstico , Valores de Referência
12.
Int Contact Lens Clin ; 26(3): 76-77, 2000 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-10863136
13.
Biochem J ; 345 Pt 3: 595-601, 2000 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-10642518

RESUMO

Two cDNAs encoding the serine protease inhibitor (serpin) neuroserpin were cloned from a rat pituitary cDNA library (rNS-1, 2922 bp; rNS-2, 1599 bp). In situ hybridization histochemistry showed neuroserpin transcripts in the intermediate, anterior and posterior lobes of the pituitary gland and medullary cells in the adrenal gland. Expression of rNS-1 mRNA was restricted to selected cells in the pituitary gland. Analysis of purified secretory-granule fractions from pituitary and adrenal tissues indicated that neuroserpin was found in dense-cored secretory granules. This result suggested that endocrine neuroserpin may regulate intragranular proteases or inhibit enzymes following regulated secretion. To investigate the function of neuroserpin in endocrine tissues we established stable anterior pituitary AtT-20 cell lines expressing neuroserpin. Cells with increased levels of neuroserpin responded by extending neurite-like processes. Extracellular proteolysis by serine protease plasminogen activators has been suggested to regulate neurite outgrowth. As neuroserpin inhibits tissue plasminogen activator (tPA) in vitro, we measured plasminogen-activator levels. Zymographic analysis indicated that AtT-20 cells synthesized and secreted a plasminogen activator identical in size to tPA. A higher-molecular-mass tPA-neuroserpin complex was also observed in AtT-20-cell conditioned culture medium. tPA levels were similar in parent AtT-20 cells and a stable cell line with increased levels of neuroserpin. There was no accumulation of a tPA-neuroserpin complex. Together these results identify endocrine cells as an important source of neuroserpin. Moreover they suggest that neuroserpin is released from dense-cored secretory granules to regulate cell-extracellular matrix interactions through a mechanism that may not directly involve tPA.


Assuntos
Glândulas Suprarrenais/metabolismo , Neuritos/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Hipófise/metabolismo , Serpinas/genética , Serpinas/metabolismo , Sequência de Aminoácidos , Animais , Bovinos , Linhagem Celular , Clonagem Molecular , Grânulos Citoplasmáticos/metabolismo , Dados de Sequência Molecular , Adeno-Hipófise/citologia , Adeno-Hipófise/metabolismo , Ratos , Inibidores de Serina Proteinase/genética , Inibidores de Serina Proteinase/metabolismo , Frações Subcelulares , Ativador de Plasminogênio Tecidual/antagonistas & inibidores , Ativador de Plasminogênio Tecidual/metabolismo , Neuroserpina
14.
J Am Optom Assoc ; 70(10): 641-6, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10561922

RESUMO

BACKGROUND: A bifocal rigid gas permeable (RGP) contact lens is now available that totally encapsulates an add segment of a different material within its inferior aspect. The purposes of this study were to determine the effects of the major lens and of its encapsulated segment region on the oxygen uptake rates of underlying cornea. METHODS: Corneal oxygen uptake rates of 10 human corneas were measured--both centrally and inferiorly--for non-wearing conditions and then immediately after 300-second wearing periods of a polymethylmethacrylate (PMMA) lens and of this RGP-encapsulated segment bifocal contact lens. Corneal responses associated with these three environmental conditions were compared statistically (i.e., without the influence of blink-driven tear flow). RESULTS: Under the nonblinking conditions maintained (i.e., with oxygen availability restricted to lens transmissibility alone), central corneal hypoxia was found for the RGP bifocal lens to be only 47% of that induced by the PMMA (Dk/L = 0) condition, while the cornea under the encapsulated segment of the bifocal lens averaged 78% of the hypoxic response induced by that same condition. Central site responses were found to be significantly different for the bifocal and the PMMA lens (p < 0.001), as they were for the two inferior sites with these two lenses (p < 0.001). All lens-related responses were found to be significantly different from the no lens condition (p < 0.001). CONCLUSIONS: Using Smith's model (JAOA, 1997) to estimate lens transmissibility, the major lens of this RGP bifocal design appears to meet approximately 80% of the Holden-Mertz daily-wear oxygen requirement--even without post-lens tear exchange, but only about 25% of that requirement appears to be met beneath the encapsulated segment region. Efficient supplementary infusion of oxygen under this lens by blink-driven tear exchange, then, is necessary to maintain optimal corneal health.


Assuntos
Lentes de Contato de Uso Prolongado , Córnea/metabolismo , Oxigênio/metabolismo , Adulto , Feminino , Humanos , Masculino , Óptica e Fotônica , Polimetil Metacrilato , Presbiopia/metabolismo , Presbiopia/terapia
15.
Optom Vis Sci ; 76(3): 135-40, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10213443

RESUMO

Introduced here are two predictive parameters, peDk/L and peDk. The prefix pe- (for physiologically effective) indicates that such values are estimates of lens transmissibility (Dk/L) and material permeability (Dk) and have been derived through a reverse application of the Residual Hypoxia model of Smith, relating corneal response (in hypoxic stress units) to lens transmissibility (Dk/L). Here, using independent databases, physiological responses to simple oxygen pathways (one layer, one material) but of unknown Dk value were entered into that model to estimate the Dk/L and (then by calculation) the Dk value of single vision rigid gas permeable (RGP) contact lenses. Also demonstrated was the application of this strategy for estimation of composite (integrated) Dk/L and Dk values of complex (multi-layer, multi-material) oxygen pathways, wherein one or more material Dk values and/or one or more local thickness are unknown.


Assuntos
Lentes de Contato , Córnea/metabolismo , Oxigênio/metabolismo , Lentes de Contato/normas , Humanos , Permeabilidade
17.
18.
Optom Vis Sci ; 75(10): 763-71, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9798217

RESUMO

The effects of rigid contact lens material [polymethyl methyacrylate (PMMA) and itabisfluorofocon A] and prism ballasting (0, 1.5, 2.25, and 3 delta) on tear pump efficiency were studied by measuring corneal oxygen uptake rates on the right eyes of six human subjects under three conditions: (1) normal open eye; (2) after 5 min of static (without blinking) wear of the contact lens; and (3) after 5 min of dynamic (with blinking once every 5 s) wear of the same lens. As expected, corneal oxygen uptake rates (i.e., demand for oxygen) measured with the itabisfluorofocon A material were significantly lower (p < 0.0001) than those measured with PMMA under both static and dynamic conditions. Under static conditions, no significant differences were found across materials among the corneal oxygen uptake rates associated with the four amounts of prism ballasting (p = 0.0514). However, under dynamic conditions, significant differences (p < 0.0001) were found across materials among corneal oxygen uptake rates associated with the four amounts of prism ballasting, with the lower amounts of prism ballasting being associated with lower corneal oxygen uptake rates. The changes in the measured corneal oxygen uptake rates from static to dynamic conditions, relative to those measured for the normal open eye, served as an index of tear pump efficiency. There were no significant differences in these changes for the prism amounts studied; however, static condition data were significantly higher than dynamic condition data for the 0 delta and 1.5 delta lenses only, whereas greater amounts of prism ballasting resulted in no reduction in oxygen uptake under dynamic conditions. In addition, significantly greater differences between static and dynamic condition data were found for the PMMA material than for itabisfluorofocon A.


Assuntos
Lentes de Contato , Córnea/metabolismo , Consumo de Oxigênio/fisiologia , Adulto , Disponibilidade Biológica , Feminino , Humanos , Masculino , Polimetil Metacrilato
19.
Am J Obstet Gynecol ; 179(4): 858-63, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9790359

RESUMO

OBJECTIVE: The aim of the study was to assess the developmental outcome of neonatal survivors of hemolytic disease of the neonate treated with modern intrauterine transfusion techniques. STUDY DESIGN: In this prospective, observational study, auditory evoked-response tests were performed in the nursery. Neurodevelopmental evaluation with the Gesell Developmental Schedules was performed between 9 and 18 months of corrected age to assess motor skills, language development, comprehension capacity, and social skills. The McCarthy Scales of Children's Abilities were administered between 36 and 62 months. RESULTS: Forty children who survived severe fetal hemolytic disease were followed up until 62 months old. Demographic data included gestational age at first intrauterine transfusion (26.4 +/- 3.7 weeks), median number of intrauterine transfusions (4, range 1-8), lowest fetal hematocrit (20.2% +/- 7.8%), peak fetal bilirubin (7.1 +/- 2.1 mg/dL), incidence of hydrops fetalis (45%), and mean gestational age at delivery (35.6 +/- 2.2 weeks). One case of severe bilateral deafness and 1 case of right spastic hemiplegia were diagnosed. The Gesell Developmental Schedules score was assessed between 9 and 18 months of corrected age in 22 infants. The global developmental quotient was 101.9 +/- 9.5 (mean for normal population is 100). Regression analysis revealed no correlation between the global developmental quotient and gestational age at the first intrauterine transfusion, gestational age at birth, or the severity of the fetal hemolytic disease (fetal hematocrit, fetal bilirubin, presence of hydrops fetalis, total number of intrauterine transfusions, duration of neonatal phototherapy, and number of neonatal exchange transfusions). Eleven of the 40 children were followed up until they were 62 months old, and the McCarthy Scales of Children's Abilities were administered. The mean cognitive index was 107.6 +/- 9.4 (90-109 is considered average). CONCLUSION: Despite severe fetal hemolytic disease, normal developmental outcome can be expected for children treated with intrauterine transfusions.


Assuntos
Transfusão de Sangue Intrauterina , Eritroblastose Fetal/terapia , Sistema Nervoso/crescimento & desenvolvimento , Bilirrubina/sangue , Pré-Escolar , Feminino , Sangue Fetal/química , Idade Gestacional , Hematócrito , Humanos , Hidropisia Fetal , Lactente , Recém-Nascido , Sistema Nervoso/embriologia , Gravidez , Estudos Prospectivos , Análise de Regressão , Resultado do Tratamento
20.
FEBS Lett ; 440(3): 361-4, 1998 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-9872403

RESUMO

We have cloned a novel serpin (raPIT5a) from a rat pituitary cDNA library which is structurally related to members of the ovalbumin subfamily of serine protease inhibitors. This new cDNA encodes a 374-amino acid protein, designated raPIT5a. raPIT5a was expressed in specific cells in the intermediate and anterior lobes of the pituitary. Recombinant raPIT5a was not secreted suggesting raPIT5a functions to inhibit intracellular proteases. Recombinant raPIT5a formed an SDS-stable complex with human granzyme B, a serine protease which induces apoptosis by activating members of the caspase enzyme family. These data suggest raPIT5a may have a role in regulating granzyme B or related enzymes and apoptosis in the pituitary gland.


Assuntos
Hipófise/metabolismo , Serina Endopeptidases/metabolismo , Inibidores de Serina Proteinase/genética , Serpinas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/análise , Granzimas , Humanos , Dados de Sequência Molecular , Neuropeptídeos , Ovalbumina/metabolismo , RNA Mensageiro/metabolismo , Ratos , Homologia de Sequência de Aminoácidos , Inibidores de Serina Proteinase/biossíntese , Serpinas/biossíntese , Neuroserpina
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