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1.
Crit Rev Food Sci Nutr ; : 1-15, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36004513

RESUMO

It has become apparent that beer (both alcoholic and nonalcoholic) contains appreciable amounts of non-starch polysaccharides, a broad subgroup of dietary fiber. It is worth noting that the occurrence of non-starch polysaccharides in alcoholic beer does not imply this should be consumed as a source of nutrition. But the popularity of nonalcoholic beer is growing, and the lessons learnt from non-starch polysaccharides in brewing can be largely translated to nonalcoholic beer. For context, we briefly review the origins of dietary fiber, its importance within the human diet and the significance of water-soluble dietary fiber in beverages. We review the relationship between non-starch polysaccharides and brewing, giving focus to the techniques used to quantify non-starch polysaccharides in beer, how they affect the physicochemical properties of beer and their influence on the brewing process. The content of non-starch polysaccharides in both regular and low/nonalcoholic beer ranges between 0.5 - 4.0 g/L and are predominantly composed of arabinoxylans and ß-glucans. The process of malting, wort production and filtration significantly affect the soluble non-starch polysaccharide content in the final beer. Beer viscosity and turbidity are strongly associated with the content of non-starch polysaccharides.

2.
Environ Sci Technol ; 53(13): 7621-7631, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31184883

RESUMO

Heat treatment, i.e., boiling or pasteurization, is the most widely recognized and practiced form of household water treatment. Considering recent advances in the development of light harvesting nanoparticles for solar-to-heat conversion, we envision that a nanomaterial enhanced water heating treatment system could obviate the need to use fuels or electricity to heat water by replacing the energy source with sunlight. In this study, we demonstrate that functional disinfection temperatures can be easily achieved with unconcentrated sunlight using a single layer interfacial photothermal film in direct contact with a tortuous flowing water channel. Photothermal films were fabricated by dispersing high concentrations of light harvesting nanoparticles, carbon black and Au nanorods, into a highly transparent curable polymer. Bench-scale 3-D printed reactors were employed to determine the effect of different parameters on reactor performance, such as channel height, retention time, flow rate, initial water temperature, and light intensity. Simulations demonstrate the scalability of the treatment system, predicting that a reactor footprint of 45 × 45 cm would be required for a photothermal treatment system that could produce 8 L of water per day with 8 h of sunlight at 1 Sun intensity.


Assuntos
Nanopartículas , Purificação da Água , Desinfecção , Luz Solar , Água
3.
J Hand Surg Eur Vol ; 49(2): 272-274, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37747739

RESUMO

Dissection of arthritic cadaveric digits revealed an expanded extensor tendon footprint involving the dorsal osteophyte on the terminal phalanx. Osteophyte attachments can be safely released up to the width of a number 15 scalpel blade without risking the integrity of the extensor tendon.


Assuntos
Falanges dos Dedos da Mão , Osteófito , Humanos , Osteófito/cirurgia , Cadáver , Tendões/cirurgia , Tendões/anatomia & histologia , Articulações dos Dedos/cirurgia
4.
Foot Ankle Surg ; 18(4): 263-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23093121

RESUMO

BACKGROUND: It is a common understanding that the fifth toe has three bones with two interphalangeal joints. However, our experience shows that a significant number have only two phalanges with one interphalangeal joint. METHODS: We identified 676 patients listed as having had a foot radiograph, during an eight week period, of which 606 radiographs were available for the assessment. The radiographs were then assessed counting the number of phalanges in the fifth toe. RESULTS: The patients consisted of 344 females and 262 males. Bilateral radiographs had been performed in 49 patients. 362 radiographs (55.3%) were found to have 3 phalanges in their 5th toe, with 291 (44.4%) having only two phalanges. CONCLUSIONS: We have demonstrated the presence of two phalanges is a common anatomical variant. This finding has clinical implications with regard to the treatment of deformities of the fifth toe and the type of internal fixation device used.


Assuntos
Articulação do Dedo do Pé/anatomia & histologia , Articulação do Dedo do Pé/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Adulto Jovem
5.
Int J Chronic Dis ; 2022: 9486679, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35462626

RESUMO

Background: Achieving good outcomes in type 2 diabetes mellitus patients' needs a decent integrated care service with access to resources. The Fiji Islands has one of the highest rates of diabetes disease burden and has available resources to alleviate the diabetic disease pandemic in its population, yet patient outcomes are getting worse. We hypothesize that a dysfunction in health-care delivery system may be accentuating the diabetic disease process; therefore, this service evaluation study was conducted to provide insight into the management of T2DM in a secondary care clinic setting. Methods: We conducted a retrospective chart review of patient records for the past three years (2015-2018). Random quota sampling was used to extract patient folders over a one-month period. A total of 113 patient charts were analyzed which met the inclusion criteria. Results: The overall glycemic levels were uncontrolled in every seven out of ten patients. Most of the patients were on combination drug therapy and at maximum dosing ranges. HbA1c tests, as a monitoring tool, were being inadequately used. Nonadherence to management was prominent in poor controlled patients, and physicians failed to provide appropriate interventions in this group. Nearly all the patients had not received eye assessments, foot risk assessment, and individualized dietetic counselling over three years. Macrovascular complications were more common than microvascular end organ damage. Conclusion: There is a high degree of uncontrolled glycemia and comorbidities in patients attending the service of study which is being perpetuated by poor integrated diabetes care. Strengthening educational initiatives, using validated strategic tools to streamline diabetic services and astute evidence-based resource allocation and management, is needed.

6.
Reproduction ; 138(1): 107-14, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19439562

RESUMO

Growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) are essential for ovarian follicular growth in sheep, whereas only GDF9 is essential in mice suggesting that the roles of these oocyte-derived growth factors differ among species. At present, however, there is only limited information on the action of BMP15 and GDF9 in other species. Thus, the aim of this experiment was to determine the effect of neutralizing GDF9 and/or BMP15 in vivo on ovarian follicular development and ovulation rate in cattle through active immunization using the mature regions of the proteins or peptides from the N-terminal area of mature regions. Immunization with the BMP15 peptide, with or without GDF9 peptide, significantly altered (increased or decreased) ovulation rate. In some animals, there were no functional corpora lutea (CL), whereas in others up to four CL were observed. From morphometric examination of the ovaries, immunization with GDF9 and/or BMP15 reduced the level of ovarian follicular development as assessed by a reduced proportion of the ovarian section occupied by antral follicles. In addition, immunization against GDF9 and/or BMP15 peptides reduced follicular size to <25% of that in the controls. In conclusion, immunization against GDF9 and BMP15, alone or together, altered follicular development and ovulation rate in cattle. Thus, as has been observed in sheep, both GDF9 and BMP15 appear to be key regulators of normal follicular development and ovulation rate in cattle.


Assuntos
Antígenos/imunologia , Proteína Morfogenética Óssea 15/imunologia , Bovinos/imunologia , Fator 9 de Diferenciação de Crescimento/imunologia , Imunização/veterinária , Folículo Ovariano/imunologia , Ovário/imunologia , Ovulação , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos/sangue , Antígenos/administração & dosagem , Antígenos/metabolismo , Proteína Morfogenética Óssea 15/administração & dosagem , Proteína Morfogenética Óssea 15/metabolismo , Bovinos/metabolismo , Feminino , Fator 9 de Diferenciação de Crescimento/administração & dosagem , Fator 9 de Diferenciação de Crescimento/metabolismo , Folículo Ovariano/metabolismo , Ovário/metabolismo
7.
FEMS Microbiol Rev ; 31(5): 535-69, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17645521

RESUMO

During brewery handling, production strains of yeast must respond to fluctuations in dissolved oxygen concentration, pH, osmolarity, ethanol concentration, nutrient supply and temperature. Fermentation performance of brewing yeast strains is dependent on their ability to adapt to these changes, particularly during batch brewery fermentation which involves the recycling (repitching) of a single yeast culture (slurry) over a number of fermentations (generations). Modern practices, such as the use of high-gravity worts and preparation of dried yeast for use as an inoculum, have increased the magnitude of the stresses to which the cell is subjected. The ability of yeast to respond effectively to these conditions is essential not only for beer production but also for maintaining the fermentation fitness of yeast for use in subsequent fermentations. During brewery handling, cells inhabit a complex environment and our understanding of stress responses under such conditions is limited. The advent of techniques capable of determining genomic and proteomic changes within the cell is likely vastly to improve our knowledge of yeast stress responses during industrial brewery handling.


Assuntos
Cerveja/microbiologia , Microbiologia Industrial , Saccharomyces cerevisiae/fisiologia , Fermentação , Regulação Fúngica da Expressão Gênica , Saccharomyces cerevisiae/genética
8.
Yeast ; 25(8): 549-62, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18668645

RESUMO

The fermentable carbohydrate composition of wort and the manner in which it is utilized by yeast during brewery fermentation have a direct influence on fermentation efficiency and quality of the final product. In this study the response of a brewing yeast strain to changes in wort fermentable carbohydrate concentration and composition during full-scale (3275 hl) brewery fermentation was investigated by measuring transcriptome changes with the aid of oligonucleotide-based DNA arrays. Up to 74% of the detectable genes showed a significant (p

Assuntos
Fermentação , Perfilação da Expressão Gênica , Microbiologia Industrial , Saccharomyces/genética , Saccharomyces/metabolismo , Cerveja/microbiologia , Transporte Biológico , Análise por Conglomerados , Etanol/metabolismo , Regulação Fúngica da Expressão Gênica , Genes Fúngicos/genética , Gluconeogênese/genética , Glicólise/genética , Saccharomyces/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
9.
Nurs Womens Health ; 22(2): 116-125, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29628051

RESUMO

Transporting a newborn out of the operating room after cesarean birth can contribute to maternal awareness of discomfort, anxiety, and the need for administration of analgesics and anxiolytics for relief. This retrospective study analyzed the association between skin-to-skin contact in the operating room and administration of analgesics and anxiolytics to women in the operating and recovery rooms after cesarean birth. Our results indicated a trend toward decreased medication administration for women who experienced skin-to-skin contact and add to evidence supporting the incorporation of skin-to-skin contact in the operating room as the standard of care for cesarean birth. This practice has the potential to enhance the birth experience, promote breastfeeding, and provide greater safety with less exposure to opioids and benzodiazepines for women and their newborns.


Assuntos
Cesárea/efeitos adversos , Relações Mãe-Filho , Gestantes/psicologia , Tato , Adolescente , Adulto , Analgésicos/efeitos adversos , Analgésicos/uso terapêutico , Ansiolíticos/efeitos adversos , Ansiolíticos/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Salas Cirúrgicas/organização & administração , Gravidez , Estudos Retrospectivos
10.
Musculoskeletal Care ; 15(4): 341-344, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28052489

RESUMO

Enhanced recovery programmes have improved outcomes following elective arthroplasty surgery. There are few studies assessing the role of patient education. In our enhanced recovery programme, all patients are offered the chance to attend a preoperative education class. Not all patients attend, enabling a comparison of outcomes. We have published data demonstrating that patients undergoing hip arthroplasty have improved outcomes. In the present article, we present data for total knee arthroplasty. Using a prospectively collected database, we identified all patients undergoing elective primary total knee arthroplasty. Data were assessed to look at patient outcomes. This was analysed using non-parametric tests. Between April 2009 and March 2013, 563 patients underwent elective total knee replacement. A total of 503 attended the class and 60 did not. Patients attending had a reduced length of stay when compared with the non-attenders but this did not reach statistical significance (4.13 days versus 4.57 days; p = 0.118). The spread of length of stay was slightly larger in the group that attended. Our analysis demonstrated that, for these patients, there is no statistically significant difference in length of stay or outcome scores. Therefore, in tougher economic times it may be prudent to focus preoperative education on total hip arthroplasty patients if resources are limited.


Assuntos
Artroplastia do Joelho , Tempo de Internação , Educação de Pacientes como Assunto , Resultado do Tratamento , Idoso , Humanos
11.
Reprod Fertil Dev ; 18(4): 403-12, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16737633

RESUMO

Sheep (Ovis aries) are a highly diverse species, with more than 900 different breeds that vary significantly in their physiological characteristics, including ovulation rate and fecundity. From examination of inherited patterns of ovulation rate, several breeds have been identified with point mutations in two growth factor genes that are expressed in oocytes. Currently, five different point mutations have been identified in the BMP15 (GDF9b) gene and one in GDF9. Animals heterozygous for the GDF9 and/or the BMP15 mutations have higher ovulation rates than their wild-type counterparts. In contrast, those homozygous for any of the aforementioned BMP15 or GDF9 mutations are sterile owing to arrested follicular development. In bovine and ovine ovaries, GDF9 was expressed exclusively in oocytes throughout follicular growth from the primordial stage of development, whereas in sheep BMP15 was expressed exclusively in oocytes from the primary stage: no data for the ontogeny of BMP15 expression are currently available for cattle. In vitro, ovine growth differentiation factor 9 (oGDF9) has no effect on (3)H-thymidine incorporation by either bovine or ovine granulosa cells, whereas ovine bone morphogenetic protein 15 (oBMP15) has modest (1.2- to 1.6-fold; P < 0.05) stimulatory effects. Ovine GDF9 or oBMP15 alone inhibited progesterone production by bovine granulosa cells, whereas in ovine cells only oGDF9 was inhibitory. The effects of oGDF9 and oBMP15 together were often cooperative and not always the same as those observed for each factor alone. Active immunisation of ewes with BMP15 and/or GDF9 peptides affected ovarian follicular development and ovulation rate. Depending on the GDF9 and/or BMP15 vaccine formulation, ovulation rate was either increased or suppressed. A primary and single booster immunisation of ewes with a BMP15 peptide in a water-based adjuvant has led to 19-40% increases in lambs born per ewe lambing. Collectively, the evidence suggests that oocyte signalling molecules have profound effects on reproduction in mammals, including rodents, humans and ruminants. Moreover, in vivo manipulation of these oocyte signalling molecules provides new opportunities for the management of the fertility of ruminants.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Oócitos/química , Reprodução/fisiologia , Ruminantes/fisiologia , Transdução de Sinais , Animais , Bovinos , Feminino , Gonadotropinas Hipofisárias/farmacologia , Imunização , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Folículo Ovariano/fisiologia , Mutação Puntual , Ovinos
12.
Theriogenology ; 85(3): 466-75, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26489910

RESUMO

The antral follicle count (AFC) in cattle is consistent throughout the estrous cycle of individual cows, and cows with a lower AFC have lower fertility. We assessed the AFC at random stages of the estrous cycle, examined the correlation between AFC classifications, and determined the relationship between the most rapid and practical laboratory-based AFC classification (AFC of follicles of ≥ 2 mm in diameter) and fertility measures in New Zealand lactating dairy cows. Cows detected in estrus (n = 202) or not (n = 239) during the first 4 weeks of the breeding season were subjected to ultrasonography and classified as having a high, medium, or low AFC at the time of scanning (on-site classification). Images from ultrasound scanning were recorded onto video for accurate follicle counting in an imaging laboratory. A strong association (P < 0.05) between the AFC of follicles with a diameter of 2 mm or greater and fertility was observed. Cows with a high AFC had a shorter (P < 0.05) interval from calving to conception by artificial insemination (AI; 82.4 ± 1.6 vs. 87.3 ± 1.2 days) and greater pregnancy rates (PRs; i.e., PR to the first AI [68.1% vs. 45.3%], 6-week PR [81.9% vs. 67.3%], and overall PR [91.3% vs. 79.7%]) than cows with a low AFC. The AFC was positively associated (P < 0.0001) with age. Progesterone concentrations during diestrus were greater (P < 0.05) in high-AFC cows (7.6 ± 0.3 ng/mL) than in low-AFC cows (6.5 ± 0.3 ng/mL), whether these were pregnant (7.7 ± 0.3 ng/mL) or not (6.3 ± 0.2 ng/mL). A rapid on-site scoring system determined that cows classified as having a high AFC had a shorter (P < 0.05) interval from calving to the first AI (76.5 ± 1.7 vs. 82.3 ± 1.9 days) and were more likely to show estrus (P < 0.01; 56.8% vs. 36.4%) and have a CL at the beginning of the breeding season (P < 0.01; 93.4% vs. 79.6%) than cows with a low on-site AFC. Collectively, we have confirmed an association between AFC2 and fertility, and these results support the hypothesis that cows with a greater number of antral follicles are more fertile than cows with a lesser number of follicles. Although the on-site classification was related to resumption of estrous cycles after calving, associations with other fertility measurements could not be observed, highlighting a need for further refinement of the on-site classification system for rapid phenotyping of the AFC.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios/métodos , Fertilidade/fisiologia , Lactação , Folículo Ovariano/anatomia & histologia , Reprodução , Animais , Cruzamento , Feminino , Fertilização/fisiologia , Humanos , Inseminação Artificial , Nova Zelândia , Folículo Ovariano/diagnóstico por imagem , Gravidez , Taxa de Gravidez , Progesterona/sangue , Fatores de Tempo , Ultrassonografia
13.
Mol Cell Endocrinol ; 192(1-2): 115-26, 2002 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-12088873

RESUMO

The oocyte derived growth differentiation factor (GDF) 9 and bone morphogenetic protein 15 (BMP15; also known as GDF9b) are essential for normal follicular growth. However, little is known about expression of these factors during ovarian development. Therefore, we determined the ontogeny of expression of GDF9 and BMP15 mRNA in the developing ovary of the brushtail possum. Ovaries were collected from pouch young (n=3-5 per group) around times of key developmental events namely: (1) morphological sexual differentiation (i.e. days 1-5 following birth), (2) after sexual differentiation (i.e. days 10-15), (3) before and during initiation of germ-cell meiosis (i.e. days 22-45), (4) shortly after initiation of follicular growth (i.e. days 78-85), (5) during preantral follicular growth (i.e. days 96-113) and (6) during antral follicular growth (i.e. days 155-190). Ovaries were also collected from three juvenile and four adult animals and gene expression was determined by in situ hybridization. The mRNAs encoding GDF9 and BMP15 were first observed in oocytes of newly-formed primordial follicles (i.e. days 78-85). Expression of both mRNAs was restricted to the oocyte and was present in follicles irrespective of whether they were non-growing primordial follicles or undergoing preantral or antral development. Thus, since the mRNAs encoding GDF9 and BMP15 were not observed until follicular formation, it is unlikely that these proteins have any role in early germ cell development. Nevertheless, the findings that the mRNAs encoding both proteins were observed in oocytes from the primordial stage of follicular formation suggest a possible role for these proteins in the maintenance of primordial follicles as well as a key role during follicular development. These results highlight important species differences in the ontogeny of expression of GDF9 and BMP15 between possums and other species such as the human, sheep or rat.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Peptídeos e Proteínas de Sinalização Intercelular/genética , Marsupiais/metabolismo , Oogênese/genética , Folículo Ovariano/metabolismo , RNA Mensageiro/biossíntese , Sequência de Aminoácidos , Animais , Proteína Morfogenética Óssea 15 , Sequência Consenso , DNA Complementar/genética , Feminino , Fator 9 de Diferenciação de Crescimento , Hibridização In Situ , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Mamíferos/metabolismo , Marsupiais/genética , Marsupiais/crescimento & desenvolvimento , Dados de Sequência Molecular , Oócitos/metabolismo , Especificidade de Órgãos , Ovário/crescimento & desenvolvimento , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Maturidade Sexual/genética
14.
J Neurosci Methods ; 131(1-2): 9-26, 2003 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-14659819

RESUMO

We describe new manufacturing techniques and physical properties of an improved polymer-based longitudinal intrafascicular electrode (polyLIFE). Modifications were made to correct: (1) poor metal film adhesion and fatigue resistance, (2) inconsistent insulation adhesion and control over recording/stimulation zone length, and (3) insufficient tensile strength for clinical use. Metal adhesion was significantly improved by both plasma treatment and fiber rotation (about the long axis) during metal deposition. Fatigue resistance was improved by reduction in sputtering energy (time x power) combined with long axis rotation, resulting in thin metal films that were 250 times more resistant to cyclic bending fatigue. Insulation adhesion was enhanced with the application of an adhesion-promoting silicone (MED2-4013, Nusil), while the recording/stimulation zone length was controlled to 1 +/- 0.2mm (mean +/- S.D.). The polyLIFE was made more robust by the inclusion of three individually metallized fibers, improving its tensile strength by a factor of 4 while producing minimal changes to its overall stiffness. However, the metallized fiber redundancy did not significantly affect fatigue resistance. The manufacturing changes described in this study enable the construction of more mechanically robust polyLIFEs, which should provide greater success when chronically implanted in peripheral nerves.


Assuntos
Materiais Revestidos Biocompatíveis/química , Eletrodos Implantados , Próteses e Implantes , Impedância Elétrica , Ouro , Teste de Materiais , Microeletrodos , Microscopia Eletrônica de Varredura/métodos , Nervos Periféricos/fisiologia , Platina , Polímeros/química , Propriedades de Superfície , Temperatura , Fatores de Tempo , Aderências Teciduais , Engenharia Tecidual , Titânio
15.
J Pharmacol Pharmacother ; 2(3): 189-90, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21897715

RESUMO

Paracetamol is one of the most commonly used drugs both over the counter and on prescription. Liquid paracetamol is available over the counter all over the world. Most commonly available concentrations are 120 mg/5 ml and 250 mg/5 ml. Many parents and healthcare professionals assume that doses available in different countries are similar. However, 500 mg/5 ml bottle is available in some countries including the United Kingdom. This leaves a potential for accidental overdose with therapeutic intent. We have reviewed the experience of diagnosing and managing an interesting case of paracetamol over dosage caused by several ingestions over 24 hours period (staggered paracetamol over dosage). It highlights the importance of communication between health professionals and parents while managing common medical problems.

16.
Case Rep Med ; 2010: 234289, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20589088

RESUMO

Lung cancer is the commonest cause of acrometastatic disease to the fingers. Here we describe a case of occult lung cancer presenting as unrelenting finger pain and swelling from a metastatic phalangeal fracture. The patient's management was largely palliative and he died soon after discovery of the primary tumor. Digital acrometastatic disease rarely becomes symptomatic before the primary lung cancer is diagnosed and, as observed in this case, carries a very poor prognosis. Clinicians should be cognizant of the strong association between digital acrometastases and bronchogenic carcinoma and vigilant in screening high-risk patients with importunate finger symptoms.

17.
Science ; 329(5999): 1624-7, 2010 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-20813921

RESUMO

Observations with the Hubble Space Telescope (HST), conducted since 1990, now offer an unprecedented glimpse into fast astrophysical shocks in the young remnant of supernova 1987A. Comparing observations taken in 2010 with the use of the refurbished instruments on HST with data taken in 2004, just before the Space Telescope Imaging Spectrograph failed, we find that the Lyα and Hα lines from shock emission continue to brighten, whereas their maximum velocities continue to decrease. We observe broad, blueshifted Lyα, which we attribute to resonant scattering of photons emitted from hot spots on the equatorial ring. We also detect N v λλ1239, 1243 angstrom line emission, but only to the red of Lyα. The profiles of the N v lines differ markedly from that of Hα, suggesting that the N4+ ions are scattered and accelerated by turbulent electromagnetic fields that isotropize the ions in the collisionless shock.

18.
Biomed Microdevices ; 10(1): 123-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17694375

RESUMO

In this paper we investigate a number of gas flames for fire polishing borosilicate glass capillaries used in the manufacturing of IVF micro-pipettes. Hydrofluoric acid (HF) was also used as an alternative to finish the pipette end. Glass micro tools in the IVF industry are drawn from hollow glass capillaries of diameter 1 mm. These capillaries are cut manually to a length of 100 mm from hollow glass rods resulting in sharp and chipped edges. These capillaries are held in a customised holder having padding of soft silicone or rubber. Sharp and uneven edges of these capillaries pick up particles of rubber or soft silicone shavings, rendering them ineffective for IVF treatments. The working range of borosilicate glass is 800-1,200 degrees C. The experiments involved analysis of fire polishing process for borosilicate glass capillaries using candle, butane, propane, 2350 butane propane, oxyacetylene gas flames, finding the optimum distance of the capillary relative to the flame, optimum time for which the capillary should be held in the flame and optimum region of the flame which gives the required temperature range. The results show that 2350 butane propane gas mix is optimum for fire polishing of borosilicate glass capillaries. The paper is concluded by comparing the results of fire polishing with the results of acid polishing, in which HF of 1.6% concentration is used to etch the ends of the borosilicate glass pipettes.


Assuntos
Fertilização in vitro/instrumentação , Ação Capilar , Vidro
19.
FEMS Yeast Res ; 8(4): 574-85, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18373683

RESUMO

Commercial brewing yeast strains are exposed to a number of potential stresses including oxidative stress. The aim of this investigation was to measure the physiological and transcriptional changes of yeast cells during full-scale industrial brewing processes with a view to determining the environmental factors influencing the cell's oxidative stress response. Cellular antioxidant levels and genome-wide transcriptional changes were monitored throughout an industrial propagation and fermentation. The greatest increase in cellular antioxidants and transcription of antioxidant-encoding genes occurred as the rapidly fermentable sugars glucose and fructose were depleted from the growth medium (wort) and the cell population entered the stationary phase. The data suggest that, contrary to expectation, the oxidative stress response is not influenced by changes in the dissolved oxygen concentration of wort but is initiated as part of a general stress response to growth-limiting conditions, even in the absence of oxygen. A mechanism is proposed to explain the changes in antioxidant response observed in yeast during anaerobic fermentation. The available data suggest that the yeast cell does not experience oxidative stress during industrial brewery handling. This information may be taken into consideration when setting parameters for industrial brewery fermentation.


Assuntos
Regulação Fúngica da Expressão Gênica , Estresse Oxidativo , Saccharomyces/fisiologia , Anaerobiose , Antioxidantes/análise , Catalase/metabolismo , Contagem de Colônia Microbiana , Meios de Cultura/química , Fermentação , Frutose/metabolismo , Perfilação da Expressão Gênica , Glucose/metabolismo , Glutationa/análise , Maltose/metabolismo , Oxigênio/análise , Saccharomyces/química , Saccharomyces/genética , Saccharomyces/crescimento & desenvolvimento , Trissacarídeos/metabolismo
20.
Biol Reprod ; 77(6): 990-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17715428

RESUMO

Woodlands sheep have a putative genetic mutation (FecX2(W)) that increases ovulation rate. At present, the identity of FecX2(W) is unknown. The trait does not appear to be due to the previously described mutations in bone morphogenetic protein 15 (BMP15), growth differentiation factor 9 (GDF9), or bone morphogenetic protein receptor type 1B (BMPR1B) that affect ovulation rate in sheep. Potentially, FecX2(W) could be an unidentified genetic mutation in BMP15 or in the closely related GDF9, which interacts with BMP15 to control ovarian function. Alternatively, FecX2(W) may affect ovulation rate by changing the expression patterns in the molecular pathways activated by genes known to regulate ovulation rate. The objectives of these experiments were to sequence the complete coding region of the BMP15 and GDF9 genes, determine the patterns of expression of mRNAs encoding GDF9, BMP15, TGFBR1, BMPR1B, and BMPR2 during follicular development, and characterize the follicular populations in ewes heterozygous for the Woodlands mutation and their wild-type contemporaries. No differences in the coding sequences of BMP15 or GDF9 genes were identified that were associated with enhanced ovulation rate. The expression patterns of GDF9 and BMPR2 mRNAs were not different between genotypes. However, expression of BMP15 mRNA was less in oocytes of FecX2(W) ewes in large preantral and antral follicles. Expression of ALK5 mRNA was significantly higher in the oocytes of FecX2(W) ewes, whereas expression of BMPR1B was decreased in both oocytes and granulosa cells of FecX2(W) ewes. FecX2(W) ewes also had increased numbers of antral follicles <1 mm in diameter. These follicles were smaller in average diameter, with the oocytes also being of a smaller mean diameter. Given that a mutation in BMP15 or BMPR1B results in increased ovulation rates in sheep, the differences in expression levels of BMP15 and BMPR1B may play a role in the increase in ovulation rate observed in Woodlands ewes with the FecX2(W) mutation.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Folículo Ovariano/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Carneiro Doméstico/metabolismo , Animais , Receptores de Proteínas Morfogenéticas Ósseas/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Fator 9 de Diferenciação de Crescimento , Peptídeos e Proteínas de Sinalização Intercelular/genética , Mutação , Folículo Ovariano/anatomia & histologia , Folículo Ovariano/crescimento & desenvolvimento , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/genética , Análise de Sequência de DNA , Carneiro Doméstico/genética
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