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1.
Reprod Toxicol ; 128: 108631, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38830453

RESUMO

Epidemiological evidence suggests the potential for air pollutants to induce male reproductive toxicity. In experimental studies, exposure to ozone during sensitive windows in the sperm lifecycle has been associated with impaired sperm motility. Subsequently, we sought to investigate the effects of episodic exposure to ozone during sperm maturation in the rat. Long-Evans rats were exposed to either filtered air or ozone (0.4 or 0.8 ppm) for five non-consecutive days over two weeks. Ozone exposure did not impact male reproductive organ weights or sperm motility ∼24 hours following the final exposure. Furthermore, circulating sex hormones remained unchanged despite increased T3 and T4 in the 0.8 ppm group. While there was indication of altered adrenergic signaling attributable to ozone exposure in the testis, there were minimal impacts on small non-coding RNAs detected in cauda sperm. Only two piwi-interacting RNAs (piRNAs) were altered in the mature sperm of ozone-exposed rats (piR-rno-346434 and piR-rno-227431). Data across all rats were next analyzed to identify any non-coding RNAs that may be correlated with reduced sperm motility. A total of 7 microRNAs (miRNAs), 8 RNA fragments, and 1682 piRNAs correlated well with sperm motility. Utilizing our exposure paradigm herein, we were unable to substantiate the relationship between ozone exposure during maturation with sperm motility. However, these approaches served to identify a suite of non-coding RNAs that were associated with sperm motility in rats. With additional investigation, these RNAs may prove to have functional roles in the acquisition of motility or be unique biomarkers for male reproductive toxicity.


Assuntos
Poluentes Atmosféricos , Ozônio , Ratos Long-Evans , Motilidade dos Espermatozoides , Animais , Masculino , Ozônio/toxicidade , Motilidade dos Espermatozoides/efeitos dos fármacos , Poluentes Atmosféricos/toxicidade , Espermatozoides/efeitos dos fármacos , Ratos , RNA Interferente Pequeno/genética
2.
PLoS One ; 13(11): e0203653, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30427840

RESUMO

Across many southern regions of Australia, native grasslands have become seriously threatened by human activity, with only a fraction of the original areas remaining undisturbed. In particular, the introduction and establishment of exotic invasive weeds has caused significant degradation to the ecosystems in these areas by contributing to a decrease in native plant density and diversity, and this has ultimately led to major changes to the ecosystem structure and function. One such example is Galenia pubescens. Our objective of this study was to assess the effectiveness of four different attempts to control G. pubescens: herbicide control with glyphosate; organic herbicide control with pine oil; the application of mulch; and the addition of seeds of native species to the seedbank. Results shows that any one single control strategy is insufficient to control G. pubescens, and, in addition, it has shown that regeneration of native vegetation is limited unless direct seeding is applied. There was a strong indication that a combined strategy employing more than two of the aforementioned techniques is likely to be the most effective approach, at least in the short term. Underscoring the complexity of this task, our analysis on foliage cover of G. pubescens shows that the interaction of pine oil and glyphosate treatments appeared to be very effective after six months, but were not so effective after 18 months. By contrast, seeding with native seeds was not particularly effective at six months, but its longer-term contribution appears to be effective at 18 months. Further, our results obtained from the seedbank abundance study indicate that time alone was not a significant factor in restoration of the grasslands (p = 0.165); however there were interactions with time, shown by time*glyphosate (p = 0.008) and time*seeding (p = 0.016). Both interactions indicated that the applications of glyphosate and seeding were more beneficial after 18 months compared to six months. However, full regeneration of invaded native grasslands may not be possible unless further restoration programs are re-implemented after the first cycle of G. pubescens' treatments have been completed.


Assuntos
Aizoaceae/crescimento & desenvolvimento , Pradaria , Espécies Introduzidas , Modelos Biológicos , Vitória
3.
Resuscitation ; 62(2): 143-50, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15294399

RESUMO

BACKGROUND: Cardiac arrest causes devastating neurological morbidity and mortality. Mild/moderate hypothermia is neuroprotective after global cerebral ischemia. More rapid controlled attainment of the target temperature may increase efficacy. METHODS: We assessed the safety and feasibility of endovascular cooling in a single arm study of comatose patients who had been successfully resuscitated after cardiac arrest. Core temperature was reduced to a target of 33 degrees C for 24 h using a closed loop endovascular system placed in the inferior vena cava, followed by controlled rewarming. Primary outcomes were speed and accuracy of cooling, survival and GOS after 30 days. RESULTS: Thirteen patients were enrolled, six male, age 60 +/- 19 years. Time from cardiac arrest to return of spontaneous circulation was 14.3 min (range 5-32.5). It took 3h and 39 min (median 210 min, IQ 80-315) to reach 33 degrees C; cooling averaged 0.8 +/- 0.3 degrees C/h (range 0.22-1.12 degrees C/h). Temperature was tightly maintained for all patients averaging 32.7 +/- 0.5 degrees C. Rewarming lasted 18.3 +/- 5.9 h. Five patients (38%) had 30-day Glasgow Outcome Scores of 1-2. Four patients died, none related to the hypothermia procedure. No unanticipated or procedure-related adverse events occurred. CONCLUSION: In comatose survivors of cardiac arrest, hypothermia via endovascular methods is safe and feasible, and target temperatures can be achieved and controlled rapidly and precisely. More studies are needed to assess the efficacy of rapid endovascular hypothermia after cardiac arrest.


Assuntos
Parada Cardíaca , Hipotermia Induzida/instrumentação , Ressuscitação/métodos , Cateteres de Demora , Estudos de Viabilidade , Feminino , Escala de Coma de Glasgow , Parada Cardíaca/terapia , Humanos , Hipotermia Induzida/métodos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Reaquecimento , Segurança , Fatores de Tempo , Veia Cava Inferior
4.
Angew Chem Int Ed Engl ; 40(13): 2509-2512, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29712276

RESUMO

The substituents at the peri positions of dehydro[14]annulenes 1 have a dramatic effect on the stability of these macrocycles, and lead to derivatives that are stable even at elevated temperatures (up to 190°C).

5.
Angew Chem Int Ed Engl ; 40(13): 2509-2512, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-11443681
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