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1.
Int J Mol Sci ; 24(19)2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37833914

RESUMO

Epileptogenesis is characterized by intrinsic changes in neuronal firing, resulting in hyperactive neurons and the subsequent generation of seizure activity. These alterations are accompanied by changes in gene transcription networks, first with the activation of early-immediate genes and later with the long-term activation of genes involved in memory. Our objective was to engineer a promoter containing binding sites for activity-dependent transcription factors upregulated in chronic epilepsy (EpiPro) and validate it in multiple rodent models of epilepsy. First, we assessed the activity dependence of EpiPro: initial electrophysiology studies found that EpiPro-driven GFP expression was associated with increased firing rates when compared with unlabeled neurons, and the assessment of EpiPro-driven GFP expression revealed that GFP expression was increased ~150× after status epilepticus. Following this, we compared EpiPro-driven GFP expression in two rodent models of epilepsy, rat lithium/pilocarpine and mouse electrical kindling. In rodents with chronic epilepsy, GFP expression was increased in most neurons, but particularly in dentate granule cells, providing in vivo evidence to support the "breakdown of the dentate gate" hypothesis of limbic epileptogenesis. Finally, we assessed the time course of EpiPro activation and found that it was rapidly induced after seizures, with inactivation following over weeks, confirming EpiPro's potential utility as a gene therapy driver for epilepsy.


Assuntos
Epilepsia , Estado Epiléptico , Ratos , Camundongos , Animais , Epilepsia/genética , Epilepsia/terapia , Epilepsia/metabolismo , Convulsões/genética , Convulsões/terapia , Convulsões/metabolismo , Neurônios/metabolismo , Estado Epiléptico/genética , Estado Epiléptico/terapia , Estado Epiléptico/metabolismo , Pilocarpina , Terapia Genética , Modelos Animais de Doenças , Hipocampo/metabolismo
2.
Am J Physiol Endocrinol Metab ; 322(6): E551-E555, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35521831

RESUMO

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged as the causative agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic that has spread worldwide, resulting in over 6 million deaths as of March 2022. Older people have been disproportionately affected by the disease, as they have a greater risk of hospitalization, are more vulnerable to severe infection, and have higher mortality than younger patients. Although effective vaccines have been rapidly developed and administered globally, several clinical trials are ongoing to repurpose existing drugs to combat severe infection. One such drug, rapamycin, is currently under study for this purpose, given its immunosuppressant effects that are mediated by its inhibition of the mechanistic target of rapamycin (mTOR), a master regulator of cell growth. Consistent with this premise, acute rapamycin administration in young healthy humans blocks or attenuates mTOR and its downstream effectors, leading to the inhibition of muscle protein synthesis (MPS). Skeletal muscle mass declines when MPS is chronically lower than muscle protein breakdown. This is consequential for older people who are more susceptible to anabolic resistance (i.e., the blunting of MPS) due to reduced activity, sedentariness, or bed rest such as that associated with COVID-19 hospitalization, and who have also demonstrated a delayed or blunted ability to regain inactivity-induced muscle loss. The lack of studies investigating rapamycin administration on skeletal muscle in older people, and the emergence of effective antiviral medications against severe infection, may indicate the reduced relevance of drug repurposing for present or future pandemics.


Assuntos
Tratamento Farmacológico da COVID-19 , Idoso , Idoso de 80 Anos ou mais , Reposicionamento de Medicamentos , Humanos , Proteínas Musculares , Músculo Esquelético , SARS-CoV-2 , Sirolimo , Serina-Treonina Quinases TOR
4.
Neurobiol Learn Mem ; 137: 134-141, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27913293

RESUMO

In addition to protein synthesis, protein degradation or protein cleavage may be necessary for intermediate (ITM) and long-term memory (LTM) to remove molecular constraints, facilitate persistent kinase activity and modulate synaptic plasticity. Calpains, a family of conserved calcium dependent cysteine proteases, modulate synaptic function through protein cleavage. We used the marine mollusk Aplysia californica to investigate the in vivo role of calpains during intermediate and long-term operant memory formation using the learning that food is inedible (LFI) paradigm. A single LFI training session, in which the animal associates a specific netted seaweed with the failure to swallow, generates short (30min), intermediate (4-6h) and long-term (24h) memory. Using the calpain inhibitors calpeptin and MDL-28170, we found that ITM requires calpain activity for induction and consolidation similar to the previously reported requirements for persistent protein kinase C activity in intermediate-term LFI memory. The induction of LTM also required calpain activity. In contrast to ITM, calpain activity was not necessary for the molecular consolidation of LTM. Surprisingly, six hours after LFI training we found that calpain activity was necessary for LTM, although this is a time at which neither persistent PKC activity nor protein synthesis is required for the maintenance of long-term LFI memory. These results demonstrate that calpains function in multiple roles in vivo during associative memory formation.


Assuntos
Aprendizagem por Associação/efeitos dos fármacos , Calpaína/antagonistas & inibidores , Condicionamento Operante/efeitos dos fármacos , Memória/efeitos dos fármacos , Animais , Aplysia , Aprendizagem por Associação/fisiologia , Condicionamento Operante/fisiologia , Inibidores de Cisteína Proteinase/farmacologia , Dipeptídeos/farmacologia , Memória/fisiologia
5.
J Dairy Sci ; 98(3): 1885-902, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25547302

RESUMO

This study investigated the effect of metabolizable protein (MP) supply and rumen-protected (RP) Lys and Met supplementation on productivity, nutrient digestibility, urinary N losses, apparent total-tract digestibility of dietary AA, and the efficiency of AA utilization for milk protein synthesis in dairy cows. The experiment was conducted with 8 ruminally cannulated Holstein cows in a replicated 4×4 Latin square design trial with 21-d periods. Treatments were (1) MP-adequate diet (AMP; MP balance of -24 g/d); (2) MP-deficient diet (DMP; MP balance of -281 g/d); (3) DMP supplemented with 100 g of RPLys/cow per day (estimated digestible Lys supply=24 g/d; DMPL; MP balance of -305g/d); and (4) DMPL supplemented with 24 g of RPMet/cow per day (estimated digestible Met supply=15 g/d; DMPLM; MP balance of -256g/d). Diet had no effect on total-tract nutrient digestibility, milk production, and milk composition, but the DMP diets decreased urinary N excretion and the ammonia emitting potential of manure. Plasma Met concentration was increased by DMPLM compared with AMP. Supplementation with RPLys had no effect on plasma Lys. Concentration of most AA in milk protein was increased or tended to be increased by DMPLM compared with DMPL. Except for the AA supplemented as RPAA (i.e., Met and Lys), apparent total-tract digestibility of all dietary AA was generally greater for the DMP diets and ranged from 33% (Arg, AMP diet) to 67% (Thr, DMPL diet). Apparent recovery of dietary AA in milk protein followed the same trends, being greater for the DMP diets than AMP and generally lower for Lys and Met with the RPAA-supplemented diets versus AMP and DMP. The RPAA were apparently not used for milk protein synthesis in the conditions of this experiment. The AA recoveries in milk protein varied from around 17% (Ala) to 70% (Pro). Milk protein recoveries of essential AA (EAA) were around 54% for the DMP diet and 49% for AMP. The estimated efficiency of utilization of digestible EAA for milk protein synthesis was generally greater for the DMP diets compared with AMP. In this trial, blood plasma Lys and Met were labeled by abomasal pulse-dose of 15N-Lys and 13C-Met (respectively). Analysis of the 15N-Lys and 13C-Met decay curves in plasma indicated trends for a faster extraction of Lys and Met from plasma for the MP-deficient diets, compared with AMP. Overall, this study confirmed conclusions from previous analyses that the efficiency of utilization of dietary EAA will increase with decreasing MP-AA supply.


Assuntos
Aminoácidos/administração & dosagem , Aminoácidos/metabolismo , Bovinos/metabolismo , Proteínas Alimentares/administração & dosagem , Proteínas do Leite/biossíntese , Rúmen/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Proteínas Alimentares/metabolismo , Suplementos Nutricionais , Digestão , Feminino , Lactação , Lisina/administração & dosagem , Lisina/sangue , Lisina/metabolismo , Metionina/administração & dosagem , Metionina/sangue , Metionina/metabolismo , Leite/química
6.
ACS Chem Neurosci ; 15(11): 2091-2098, 2024 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-38747710

RESUMO

Xylazine (also known as "tranq") is a potent nonopioid veterinary sedative that has recently experienced a surge in use as a drug adulterant, most often combined with illicitly manufactured fentanyl. This combination may heighten the risk of fatal overdose. Xylazine has no known antidote approved for use in humans, and age-adjusted overdose deaths involving xylazine were 35 times higher in 2021 than 2018. In April 2023, the Biden Administration declared xylazine-laced fentanyl an emerging drug threat in the United States. In 2022, the Drug Enforcement Agency (DEA) reported nearly a quarter of seized fentanyl powder contained xylazine. This dramatic increase in prevalence has solidified the status of xylazine as an emerging drug of abuse and an evolving threat to public health. The following narrative review outlines the synthesis, pharmacokinetics, pharmacodynamics, and adverse effects of xylazine, as well as the role it may play in the ongoing opioid epidemic.


Assuntos
Xilazina , Xilazina/farmacologia , Humanos , Animais , Hipnóticos e Sedativos/farmacologia , Hipnóticos e Sedativos/química , Fentanila/farmacologia , Fentanila/química , Analgésicos Opioides/química , Analgésicos Opioides/farmacologia , Overdose de Drogas/epidemiologia
7.
Behav Brain Res ; 474: 115208, 2024 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-39154755

RESUMO

Existing maze apparatuses used in rodents often exclusively assess spatial discriminability as a means to evaluate learning impairments. Spatial learning in such paradigms is reportedly spared by moderate prenatal alcohol exposure in rats, suggesting that spatial reinforcement alone is insufficient to delineate executive dysfunction, which consistently manifests in humans prenatally-exposed to alcohol. To address this, we designed a single-session continuous performance task in the T-maze apparatus that requires rats to discriminate within and between simultaneously-presented spatial (left or right) and tactile (sandpaper or smooth) stimuli for food reinforcement across four sequential discrimination stages: simple discrimination, intradimensional reversal 1, extradimensional shift, and intradimensional reversal 2. This design incorporates elements of working memory, attention, and goal-seeking behavior which collectively contribute to the executive function construct. Here, we found that rats prenatally-exposed to alcohol performed worse in both the tactile intradimensional reversal and extradimensional shift; alternatively, rats prenatally-exposed to alcohol acquired the extradimensional shift faster when shifting from the tactile to spatial dimension. In line with previous work, moderate prenatal alcohol exposure spared specifically spatial discrimination in this paradigm. However, when tactile stimuli were mapped into the spatial dimension, rats prenatally-exposed to alcohol required more trials to discriminate between the dimensions. We demonstrate that tactile stimuli can be operantly employed in a continuous performance T-maze task to detect discriminatory learning impairments in rats exposed to moderate prenatal alcohol. The current paradigm may be useful for assessing features of executive dysfunction in rodent models of fetal alcohol spectrum disorders.


Assuntos
Etanol , Aprendizagem em Labirinto , Efeitos Tardios da Exposição Pré-Natal , Animais , Gravidez , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Feminino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Etanol/farmacologia , Etanol/administração & dosagem , Etanol/efeitos adversos , Masculino , Ratos , Ratos Long-Evans , Percepção Espacial/efeitos dos fármacos , Percepção Espacial/fisiologia , Discriminação Psicológica/efeitos dos fármacos , Discriminação Psicológica/fisiologia , Percepção do Tato/fisiologia , Percepção do Tato/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Memória de Curto Prazo/fisiologia , Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Tato/fisiologia , Tato/efeitos dos fármacos
8.
J Dairy Sci ; 96(12): 7892-903, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24119814

RESUMO

Three experiments (Exp.) were conducted to study the effects of dietary addition of an essential oil product (EO) based on eugenol and cinnamaldehyde (0, control, or 525 mg/d of Xtract 6965; Pancosma SA, Geneva, Switzerland) on ruminal fermentation, total-tract digestibility, manure gas emissions, N losses, and dairy cow performance. In Exp. 1 and 3, the EO supplement was added to the vitamin-mineral premix. In Exp. 2, EO was top-dressed. Experiments 1 and 2 were crossover designs with 20 multiparous Holstein cows each (including 4 and 8 ruminally cannulated cows, respectively) and consisted of two 28-d periods. Intake of dry matter did not differ between treatments. Most ruminal fermentation parameters were unaffected by EO. Concentrations of ammonia (Exp. 1), isobutyrate (Exp. 1 and 2), and isovalerate (Exp. 1) were increased by EO compared with the control. Apparent total-tract digestibility of nutrients was similar between treatments, except total-tract digestibility of neutral-detergent fiber, which was increased or tended to be increased by EO in Exp. 1 and 2. Manure emissions of ammonia and methane were unaffected by EO. Blood plasma and milk urea-N concentrations and urinary N losses were increased by EO compared with the control in Exp. 1, but not in Exp. 2. Average milk yield, 3.5% fat-corrected milk yield, and milk fat, protein, and lactose concentrations were unaffected by treatment. Urinary excretion of purine derivatives, a marker for microbial protein production in the rumen, was greater in cows receiving the EO diet in Exp. 1, but not in Exp. 2. In Exp. 3, 120 Holstein cows were grouped in pens of 20 cows/pen in a 12-wk experiment to study production effects of EO. Dry matter intake, milk yield (a trend for a slight decrease with EO), milk components, milk urea N, and feed efficiency were similar between treatments. Results from these studies indicate that supplementing dairy cows with 525 mg/d of Xtract 6965 had moderate effects on ruminal fermentation, but consistently increased ruminal isobutyrate concentration and tended to increase total-tract digestibility of neutral-detergent fiber. Under the conditions of these experiments, Xtract 6965 fed at 525 mg/d did not affect milk production or composition.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais , Lactação/efeitos dos fármacos , Óleos Voláteis/farmacologia , Rúmen/efeitos dos fármacos , Amônia/análise , Ração Animal/análise , Animais , Dieta/veterinária , Digestão/efeitos dos fármacos , Feminino , Fermentação , Lactação/fisiologia , Lactose/metabolismo , Esterco , Metano/metabolismo , Leite/química , Óleos Voláteis/administração & dosagem , Rúmen/metabolismo , Suíça
9.
J Dairy Sci ; 96(2): 1189-202, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23245964

RESUMO

This experiment investigated the effects of dietary supplementation of Origanum vulgare L. leaf material (OR) on rumen fermentation, production, and milk fatty acid composition in dairy cows. The experimental design was a replicated 4 × 4 Latin square with 8 rumen-cannulated Holstein cows and 20-d experimental periods. Treatments were control (no OR supplementation), 250 g/cow per day OR (LOR), 500 g/d OR (MOR), and 750 g/d OR (HOR). Oregano supplementation had no effect on rumen pH, volatile fatty acid concentrations, and estimated microbial protein synthesis, but decreased ammonia concentration and linearly decreased methane production per unit of dry matter intake (DMI) compared with the unsupplemented control: 18.2, 16.5, 11.7, and 13.6g of methane/kg of DMI, respectively. Proportions of rumen bacterial, methanogen, and fungal populations were not affected by treatment. Treatment had no effect on total-tract apparent digestibility of dietary nutrients, except neutral detergent fiber digestibility was slightly decreased by all OR treatments compared with the control. Urinary N losses and manure odor were not affected by OR, except the proportion of urinary urea N in the total excreted urine N tended to be decreased compared with the control. Oregano linearly decreased DMI (28.3, 28.3, 27.5, and 26.7 kg/d for control, LOR, MOR, and HOR, respectively). Milk yield was not affected by treatment: 43.4, 45.2, 44.1, and 43.4 kg/d, respectively. Feed efficiency was linearly increased with OR supplementation and was greater than the control (1.46, 1.59, 1.60, and 1.63 kg/kg, respectively). Milk composition was unaffected by OR, except milk urea-N concentration was decreased. Milk fatty acid composition was not affected by treatment. In this short-term study, OR fed at 250 to 750 g/d decreased rumen methane production in dairy cows within 8h after feeding, but the effect over a 24-h feeding cycle has not been determined. Supplementation of the diet with OR linearly decreased DMI and increased feed efficiency. Oregano had no effects on milk fatty acid composition.


Assuntos
Ácidos Graxos/análise , Fermentação/efeitos dos fármacos , Lactação/efeitos dos fármacos , Leite/química , Origanum , Rúmen/efeitos dos fármacos , Ração Animal , Animais , Bovinos , Suplementos Nutricionais , Feminino , Lactação/fisiologia , Folhas de Planta , Rúmen/fisiologia
10.
J Dairy Sci ; 96(12): 7830-43, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24140326

RESUMO

This study investigated the effect of phytonutrients (PN) supplied postruminally on nutrient utilization, gut microbial ecology, immune response, and productivity of lactating dairy cows. Eight ruminally cannulated Holstein cows were used in a replicated 4×4 Latin square. Experimental periods lasted 23 d, including 14-d washout and 9-d treatment periods. Treatments were control (no PN) and daily doses of 2g/cow of either curcuma oleoresin (curcumin), garlic extract (garlic), or capsicum oleoresin (capsicum). Phytonutrients were pulse-dosed into the abomasum of the cows, through the rumen cannula, 2 h after feeding during the last 9 d of each experimental period. Dry matter intake was not affected by PN, although it tended to be lower for the garlic treatment compared with the control. Milk yield was decreased (2.2 kg/d) by capsicum treatment compared with the control. Feed efficiency, milk composition, milk fat and protein yields, milk N efficiency, and 4.0% fat-corrected milk yield were not affected by treatment. Rumen fermentation variables, apparent total-tract digestibility of nutrients, N excretion with feces and urine, and diversity of fecal bacteria were also not affected by treatment. Phytonutrients had no effect on blood chemistry, but the relative proportion of lymphocytes was increased by the capsicum treatment compared with the control. All PN increased the proportion of total CD4(+) cells and total CD4(+) cells that co-expressed the activation status signal and CD25 in blood. The percentage of peripheral blood mononuclear cells (PBMC) that proliferated in response to concanavalin A and viability of PBMC were not affected by treatment. Cytokine production by PBMC was not different between control and PN. Expression of mRNA in liver for key enzymes in gluconeogenesis, fatty acid oxidation, and response to reactive oxygen species were not affected by treatment. No difference was observed due to treatment in the oxygen radical absorbance capacity of blood plasma but, compared with the control, garlic treatment increased 8-isoprostane levels. Overall, the PN used in this study had subtle or no effects on blood cells and blood chemistry, nutrient digestibility, and fecal bacterial diversity, but appeared to have an immune-stimulatory effect by activating and inducing the expansion of CD4 cells in dairy cows. Capsicum treatment decreased milk yield, but this and other effects observed in this study should be interpreted with caution because of the short duration of treatment.


Assuntos
Ração Animal/análise , Capsicum , Bovinos/imunologia , Curcumina , Suplementos Nutricionais , Alho , Abomaso/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos/fisiologia , Dieta/veterinária , Fezes/química , Feminino , Fermentação , Lactação/fisiologia , Leite/química , Rúmen/fisiologia
11.
QJM ; 116(4): 288-291, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-36519833

RESUMO

INTRODUCTION: Previous studies have shown an association between number of stroke admissions and outcomes. Small hospitals often support more remote areas and we studied national data to determine if an association exists between hospital remoteness and stroke care. METHODS: Data from the Irish National Audit of Stroke (INAS) on average stroke admissions, adjusted mortality for ischaemic stroke, thrombolysis rate and proportion with door to needle (DTN) ≤45 min were analysed. Hospital remoteness was quantified by distance to the next hospital, nearest neurointerventional centre and location within 10 km of the national motorway network. RESULTS: Data for 23 of 24 stroke services were evaluated. Median number of strokes admitted per year was 186 (range 84-497). Nine hospitals (39%) admitted ≥200 stroke patients per year (mean 332). Average adjusted mortality (7.0 vs. 7.3, P = 0.67 t-test), mean thrombolysis rate (12.1% vs. 9.2%, P = 0.09) and mean proportion of patients treated ≤45 min (40.4% vs. 31.3%, P = 0.2) did not differ significantly between higher and lower volume hospitals.Hospitals close to the motorway network (n = 15) had a higher mean thrombolysis rate (11.9% vs. 7.5%, P = 0.01 t-test) and proportion DTN ≤45 min (43.7-18.4%, P < 0.001).Number of stroke admissions did not correlate with mortality (r = 0.06, P = 0.78), DTN (r = 0.12, P = 0.95) or thrombolysis rate (r = 0.35, P = 0.20). Distance to next hospital correlated strongly negatively with DTN (r = -0.47, P = 0.02) and thrombolysis rate (-0.43, P = 0.04). CONCLUSION: Remoteness of hospitals is associated with worse measures of stroke outcome and management.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Isquemia Encefálica/complicações , Terapia Trombolítica , Tamanho das Instituições de Saúde , Tempo para o Tratamento , Resultado do Tratamento
12.
Sports Med Health Sci ; 5(1): 10-19, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36994172

RESUMO

Skeletal muscle anabolism is driven by numerous stimuli such as growth factors, nutrients (i.e., amino acids, glucose), and mechanical stress. These stimuli are integrated by the mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) signal transduction cascade. In recent years, work from our laboratory and elsewhere has sought to unravel the molecular mechanisms underpinning the mTOR-related activation of muscle protein synthesis (MPS), as well as the spatial regulation of these mechanisms within the skeletal muscle cell. These studies have suggested that the skeletal muscle fiber periphery is a region of central importance in anabolism (i.e., growth/MPS). Indeed, the fiber periphery is replete with the substrates, molecular machinery, and translational apparatus necessary to facilitate MPS. This review provides a summary of the mechanisms underpinning the mTOR-associated activation of MPS from cell, rodent, and human studies. It also presents an overview of the spatial regulation of mTORC1 in response to anabolic stimuli and outlines the factors that distinguish the periphery of the cell as a highly notable region of skeletal muscle for the induction of MPS. Future research should seek to further explore the nutrient-induced activation of mTORC1 at the periphery of skeletal muscle fibers.

13.
PLOS Glob Public Health ; 3(8): e0002190, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37531350

RESUMO

This qualitative study examines the social determinants of health among noncitizen deported United States veterans. We utilized Photovoice, a participatory action research method used to inform structural level change, with 12 veterans. Audio-recorded semi-structured interviews explored photos and discussed deportation's effects on veteran health. We performed rapid template and matrix analysis of interview transcripts. Interviews were conducted in Tijuana, Mexico from December 2018 to January 2019. Study findings show that veterans prioritize returning to the United States to improve their quality of life. Analysis of photos and narrative text indicated that deportation caused social, economic, and political insecurities. Veterans struggled to maintain access to necessities post-deportation. Disrupted social networks compounded their situation, resulting in chronic stress and poor health outcomes. The findings from this study offer insight into the ways deportation acts as a social determinant of health. The findings suggest modifying veteran reintegration programs, as well as reforming criminal justice and immigration laws, such as creating more Veteran Treatment Courts and allowing immigration judges to consider military history during deportation proceedings involving noncitizen veterans.

14.
J Dairy Sci ; 95(9): 5253-5268, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22916930

RESUMO

Two experiments were conducted with the objective of investigating the effects of rumen-protected methionine (RPMet) supplementation of metabolizable protein (MP)-deficient or MP-adequate but Met-deficient diets on dairy cow performance. Experiment (Exp.) 1 utilized 36 Holstein dairy cows blocked in 12 blocks of 3 cows each. Cows within block were assigned to one of the following dietary treatments: (1) MP-adequate diet [AMP; positive MP balance according to the National Research Council (2001) dairy model]; (2) an MP-deficient diet supplemented with 100g of rumen-protected Lys (RPLys)/cow per day (DMPL); and (3) DMPL supplemented with 24 g of RPMet/cow per day (DMPLM). Experiment 2 utilized 120 Holstein cows assigned to 6 pens of 20 cows each. Pens (3 per treatment) were assigned to one of the following dietary treatments: (1) AMP diet supplemented with 76 g of RPLys/cow per day (AMPL); and (2) AMPL (74 g of RPLys/cow per day) supplemented with 24 g of RPMet/cow per day (AMPLM). Each experiment lasted for 10 wk (2-wk adaptation and 8-wk experimental periods) following a 2-wk covariate period (i.e., a total of 12 wk). In Exp. 1, the MP-deficient diets decreased apparent total-tract nutrient digestibility but had no statistical effect on dry matter intake (DMI), milk yield, or milk fat percentage and yield. Compared with AMP, DMPL decreased milk protein content; both DMPL and DMPLM diets decreased milk protein yield. Urinary N losses and milk urea-N concentration were decreased by the MP-deficient diets compared with AMP. The ammonia emitting potential of manure from the MP-deficient diets was decreased by about 37% compared with that of AMP manure. Plasma Lys and Met concentrations were not affected by treatment, but concentrations of His, Thr, and Val were lower for the MP-deficient diets compared with AMP. In Exp. 2, the AMPLM diet had lower milk yield than AMPL due to numerically lower DMI; no other effects were observed in Exp. 2. In conclusion, feeding MP-deficient diets supplemented with RPLys and RPMet did not statistically decrease milk yield in dairy cows in Exp. 1. However, without RPMet supplementation, milk protein content was decreased compared with the MP-adequate diet. Other amino acids, possibly His, may limit milk production in MP-deficient, corn or corn silage-based diets. A summary of 97 individual cow data from trials in which MP-deficient diets were fed suggested the National Research Council (2001) model under-predicts milk yield in cows fed MP-deficient diets (MP balance of -20 to -666 g/d) in a linear manner: milk yield under-prediction [National Research Council (2001) MP-allowable milk yield, kg/d - actual milk yield, kg/d] = 0.0991 (±0.0905) + 0.0230 (±0.0003) × MP balance, g/d (R(2)=0.99).


Assuntos
Amônia/metabolismo , Proteínas Alimentares/farmacologia , Suplementos Nutricionais , Lactação/efeitos dos fármacos , Lisina/farmacologia , Esterco/análise , Metionina/farmacologia , Nitrogênio/metabolismo , Amônia/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais , Bovinos , Dieta , Feminino , Lactação/fisiologia
15.
J Dairy Sci ; 95(6): 3310-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22612964

RESUMO

The effects of dry glycerol as a partial replacement for dietary starch in a lactating cow diet on ruminal fermentation and bacterial protein synthesis were evaluated using 4 single-flow, continuous-culture fermentors (ranging from 1,015 to 1,040 mL in volume). The basal lactating cow diet was formulated to have partial contents of dietary starch provided from a corn starch supplement [at 12.37% diet dry matter (DM)], which was partially or completely replaced by a dry glycerol product. Both the corn starch supplement and dry glycerol product contained 65% of pure corn starch or glycerol, respectively. The final inclusion rate for pure glycerol was at 0, 3, 5, or 8% of DM in the basal diet. The experiment was conducted using a 4 × 4 Latin square design with four 9-d periods, with the first 6 d for adaptation and last 3 d for sampling. Fermentors were inoculated with 1L of ruminal fluid and 25 g of ruminal digesta from a ruminally cannulated cow receiving a lactation total mixed ration (16% crude protein, 32% neutral detergent fiber, and 25% starch; DM basis). Each fermentor was fed 75 g of DM of its respective experimental diet daily in 3 equal portions (at 0800, 1400, and 2000 h). Liquid dilution rate of the fermentors was maintained at 10%/h and solids retention time was set at 24 h. Fermentation fluid and the effluent from each fermentor were sampled once daily (at 1330 h) from d 7 to 9 of each period and pooled by period. Postprandial ruminal fermentation was studied by sampling the fermentors hourly for 5 h after the 0800 h feeding on d 9 of each period. The total fermentation contents were harvested at the end of the period for estimations of bacterial protein synthesis. Replacing corn starch with dry glycerol linearly increased the proportions of propionate and valerate at the expense of acetate in the fermentation fluid measured daily or for the first 5h after feeding. Replacing corn starch with dry glycerol also linearly increased the digestibility of dietary neutral detergent fiber without a change on the flow or efficiency of bacterial protein synthesis during continuous culture. Results indicate that glycerol as a dry product can replace dietary starch as corn starch at a level of up to 8% of DM in the diet without negatively affecting ruminal fermentation and digestibility during continuous culture.


Assuntos
Dieta/veterinária , Carboidratos da Dieta/metabolismo , Fermentação/efeitos dos fármacos , Glicerol/metabolismo , Rúmen/fisiologia , Amido/metabolismo , Animais , Proteínas de Bactérias/análise , Bovinos/fisiologia , Suplementos Nutricionais , Feminino , Fermentação/fisiologia , Conteúdo Gastrointestinal/química , Conteúdo Gastrointestinal/microbiologia , Lactação/fisiologia , Rúmen/metabolismo
16.
J Dairy Sci ; 95(10): 6042-56, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22863104

RESUMO

The objective of this experiment was to evaluate the effect of supplementing a metabolizable protein (MP)-deficient diet with rumen-protected (RP) Lys, Met, and specifically His on dairy cow performance. The experiment was conducted for 12 wk with 48 Holstein cows. Following a 2-wk covariate period, cows were blocked by DIM and milk yield and randomly assigned to 1 of 4 diets, based on corn silage and alfalfa haylage: control, MP-adequate diet (ADMP; MP balance: +9 g/d); MP-deficient diet (DMP; MP balance: -317 g/d); DMP supplemented with RPLys (AminoShure-L, Balchem Corp., New Hampton, NY) and RPMet (Mepron; Evonik Industries AG, Hanau, Germany; DMPLM); and DMPLM supplemented with an experimental RPHis preparation (DMPLMH). The analyzed crude protein content of the ADMP and DMP diets was 15.7 and 13.5 to 13.6%, respectively. The apparent total-tract digestibility of all measured nutrients, plasma urea-N, and urinary N excretion were decreased by the DMP diets compared with ADMP. Milk N secretion as a proportion of N intake was greater for the DMP diets compared with ADMP. Compared with ADMP, dry matter intake (DMI) tended to be lower for DMP, but was similar for DMPLM and DMPLMH (24.5, 23.0, 23.7, and 24.3 kg/d, respectively). Milk yield was decreased by DMP (35.2 kg/d), but was similar to ADMP (38.8 kg/d) for DMPLM and DMPLMH (36.9 and 38.5kg/d, respectively), paralleling the trend in DMI. The National Research Council 2001model underpredicted milk yield of the DMP cows by an average (±SE) of 10.3 ± 0.75 kg/d. Milk fat and true protein content did not differ among treatments, but milk protein yield was increased by DMPLM and DMPLMH compared with DMP and was not different from ADMP. Plasma essential amino acids (AA), Lys, and His were lower for DMP compared with ADMP. Supplementation of the DMP diets with RP AA increased plasma Lys, Met, and His. In conclusion, MP deficiency, approximately 15% below the National Research Council requirements from 2001, decreased DMI and milk yield in dairy cows. Supplementation of the MP-deficient diet with RPLys and RPMet diminished the difference in DMI and milk yield compared with ADMP and additional supplementation with RPHis eliminated it. As total-tract fiber digestibility was decreased with the DMP diets, but DMI tended to increase with RP AA supplementation, we propose that, similar to monogastric species, AA play a role in DMI regulation in dairy cows. Our data implicate His as a limiting AA in high-producing dairy cows fed corn silage- and alfalfa haylage-based diets, deficient in MP. The MP-deficient diets clearly increased milk N efficiency and decreased dramatically urinary N losses.


Assuntos
Histidina/farmacologia , Lactação/efeitos dos fármacos , Lisina/farmacologia , Metionina/farmacologia , Proteínas do Leite/análise , Leite/química , Deficiência de Proteína/veterinária , Rúmen/metabolismo , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais , Bovinos , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/fisiopatologia , Dieta/veterinária , Proteínas Alimentares/farmacologia , Suplementos Nutricionais , Feminino , Histidina/metabolismo , Histidina/fisiologia , Lactação/metabolismo , Lactação/fisiologia , Lisina/metabolismo , Lisina/fisiologia , Metionina/metabolismo , Metionina/fisiologia , Deficiência de Proteína/metabolismo , Deficiência de Proteína/fisiopatologia , Rúmen/fisiologia
17.
Int J Stroke ; 17(2): 163-171, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33538655

RESUMO

BACKGROUND: Inflammation driven by pro-inflammatory cytokines is a new therapeutic target in coronary disease. Few data exist on the association of key upstream cytokines and post-stroke recurrence. In a prospective cohort study, we investigated the association between pivotal cytokines, high-sensitivity C-reactive protein (hsCRP) and one-year outcomes. METHODS: BIO-STROKETIA is a multi-center prospective cohort study of non-severe ischemic stroke (modified Rankin score ≤ 3) and transient ischemic attack. Controls were patients with transient symptoms attending transient ischemic attack clinics with non-ischemic final diagnosis. Exclusion criteria were severe stroke, infection, and other pro-inflammatory disease; hsCRP and cytokines (interleukin (IL) 6, IL-1ß, IL-8, IL-10, IL-12, interferon-γ (IFN-γ), tumor-necrosis factor-α (TNF-α)) were measured. The primary outcome was one-year recurrent stroke/coronary events (fatal and non-fatal). RESULTS: In this study, 680 patients (439 stroke, 241 transient ischemic attack) and 68 controls were included. IL-6, IL-1ß, IL-8, IFN-γ, TNF-α, and hsCRP were higher in stroke/transient ischemic attack cases (p ≤ 0.01 for all). On multivariable Cox regression, IL-6, IL-8, and hsCRP independently predicted one-year recurrent vascular events (adjusted hazard ratios (aHR) per-quartile increase IL-6 1.31, confidence interval (CI) 1.02-1.68, p = 0.03; IL-8 1.47, CI 1.15-1.89, p = 0.002; hsCRP 1.28, CI 1.01-1.62, p = 0.04). IL-6 (aHR 1.98, CI 1.26-3.14, p = 0.003) and hsCRP (aHR 1.81, CI 1.20-2.74, p = 0.005) independently predicted one-year fatality. IL-6 and hsCRP (adjusted odds ratio per-unit increase 1.02, CI 1.01-1.04) predicted poor functional outcome, with a trend for IL-1ß (p = 0.054). CONCLUSION: Baseline inflammatory cytokines independently predicted late recurrence, supporting a rationale for randomized trials of anti-inflammatory agents for prevention after stroke and suggesting that targeted therapy to high-risk patients with high baseline inflammation may be beneficial.


Assuntos
Proteína C-Reativa , Citocinas , Ataque Isquêmico Transitório , Acidente Vascular Cerebral , Proteína C-Reativa/metabolismo , Humanos , Ataque Isquêmico Transitório/complicações , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/complicações
18.
J Dairy Sci ; 94(1): 382-95, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21183049

RESUMO

The objectives of this experiment were to investigate the effects of lauric (LA) and myristic (MA) acids on ruminal fermentation, production, and milk fatty acid (FA) profile in lactating dairy cows and to identify the FA responsible for the methanogen-suppressing effect of coconut oil. The experiment was conducted as a replicated 3×3 Latin square. Six ruminally cannulated cows (95±26.4 DIM) were subjected to the following treatments: 240 g/cow per day each of stearic acid (SA, control), LA, or MA. Experimental periods were 28 d and cows were refaunated between periods. Lauric acid reduced protozoal counts in the rumen by 96%, as well as acetate, total VFA, and microbial N outflow from the rumen, compared with SA and MA. Ruminal methane production was not affected by treatment. Dry matter intake was reduced 35% by LA compared with SA and MA, which resulted in decreased milk yield. Milk fat content also was depressed by LA compared with SA and MA. Treatment had no effect on milk protein content. All treatments increased milk concentration of the respective treatment FA. Concentration of C12:0 was more than doubled by LA, and C14:0 was increased (45%) by MA compared with SA. Concentration of milk FAC16 FA and MUFA were increased, by LA compared with the other treatments. In this study, LA had profound effects on ruminal fermentation, mediated through inhibited microbial populations, and decreased DMI, milk yield, and milk fat content. Despite the significant decrease in protozoal counts, however, LA had no effect on ruminal methane production. Thus, the antimethanogenic effect of coconut oil, observed in related studies, is likely due to total FA application level, the additive effect of LA and MA, or a combination of both. Both LA and MA modified milk FA profile significantly.


Assuntos
Ácidos Graxos/análise , Fermentação/efeitos dos fármacos , Lactação/efeitos dos fármacos , Ácidos Láuricos/farmacologia , Leite/química , Ácidos Mirísticos/farmacologia , Rúmen/efeitos dos fármacos , Animais , Bovinos , Feminino , Metano/biossíntese , Rúmen/metabolismo , Rúmen/microbiologia , Rúmen/parasitologia
19.
J Dairy Sci ; 94(11): 5544-57, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22032378

RESUMO

The objective of this study was to investigate the effect of metabolizable protein (MP) deficiency and coconut oil supplementation on N utilization and production in lactating dairy cows. The hypothesis of the study was that a decrease in ruminal protozoal counts with coconut oil would increase microbial protein synthesis in the rumen, thus compensating for potential MP deficiency. The experiment was conducted for 10 wk with 36 cows (13 primiparous and 23 multiparous), including 6 ruminally cannulated cows. The experimental period, 6 wk, was preceded by 2-wk adaptation and 2-wk covariate periods. Cows were blocked by parity, days in milk, milk yield, and rumen cannulation and randomly assigned to one of the following diets: a diet with a positive MP balance (+44 g/d) and 16.7% dietary crude protein (CP) concentration (AMP); a diet deficient in MP (-156 g/d) and 14.8% CP concentration (DMP); or DMP supplemented with approximately 500 g of coconut oil/head per day (DMPCO). Ruminal ammonia tended to be greater and plasma urea N (20.1, 12.8, and 13.1 mg/dL, for AMP, DMP, and DMPCO diets, respectively) and milk urea N (12.5, 8.3, and 9.5mg/dL, respectively) were greater for AMP compared with DMP and DMPCO. The DMPCO diet decreased total protozoa counts (by 60%) compared with DMP, but had no effect on the methanogens profile in the rumen. Total tract apparent digestibility of dry matter and CP was decreased by DMP compared with AMP. Fiber digestibility was lower for both DMP and DMPCO compared with AMP. Urinary N excretion was decreased (by 37%) by both DMP and DMPCO compared with AMP. The DMP and DMPCO diets resulted in greater milk N efficiency compared with AMP (32.0 and 35.1 vs. 27.6%, respectively). Milk yield was decreased by both DMP and DMPCO compared with AMP (36.2, 34.4, and 39.3 kg/d, respectively) and coconut oil supplementation suppressed feed intake and caused milk fat depression. Coconut oil supplementation decreased short-chain fatty acid (C4:0, C6:0, and C8:0) concentration and increased medium-chain (C12:0 and C14:0) and total trans fatty acids in milk. Overall, the MP-deficient diets decreased N losses, but could not sustain milk production in this study. Coconut oil decreased feed intake and similar to DMP, suppressed fiber digestibility. Despite decreased protozoal counts, coconut oil had no effect on the methanogen population in the rumen.


Assuntos
Bovinos , Dieta/veterinária , Proteínas Alimentares/metabolismo , Suplementos Nutricionais , Lactação , Nitrogênio/metabolismo , Óleos de Plantas , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bactérias/metabolismo , Bovinos/metabolismo , Bovinos/fisiologia , Óleo de Coco , Digestão/fisiologia , Ingestão de Alimentos/fisiologia , Feminino , Fermentação/fisiologia , Lactação/metabolismo , Leite/química , Leite/metabolismo , Distribuição Aleatória , Rúmen/metabolismo , Rúmen/microbiologia
20.
J Dairy Sci ; 94(8): 4057-74, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21787941

RESUMO

The objective of this experiment was to investigate the effects of replacing conventional, solvent-extracted canola meal (control; CTRL) with high oil content; conventional, mechanically extracted canola meal (CMEC); high-oleic, low polyunsaturated fatty acid (FA) canola meal (HOLL); and high-erucic acid, low-glucosinolate rapeseed meal (RPS) on rumen function, digestibility, milk production, and milk FA composition in lactating dairy cows. The experimental design was a replicated 4×4 Latin square with 8 lactating dairy cows. Four of the cows were ruminally cannulated. All oilseed meals were included at approximately 12 to 13% of dietary dry matter (DM). Crude protein and fat concentrations (% of DM) of the meals were 43 and 3.1%, 32.8 and 16.1%, 45.2 and 13.7%, and 34.3 and 17.9% for CTRL, CMEC, HOLL, and RPS, respectively. All diets were formulated to supply net energy of lactation in excess of requirements. The CMEC and RPS diets were predicted to be about 1% deficient in metabolizable protein. Relative to the CTRL, inclusion of high-oil seed meals in the diet lowered ruminal acetate concentration and the molar acetate:propionate ratio and decreased DM intake. Milk yield generally followed DM intake and was lower for CMEC and RPS than the CTRL. Treatments had no effect on milk composition, other than an increase in milk urea nitrogen concentration for HOLL. Fat-corrected milk (3.5%) feed efficiency was increased by HOLL and RPS compared with CTRL. Urinary urea nitrogen losses were increased by HOLL, which, as a consequence, increased the ammonia-emitting potential of manure. The ratio of milk N-to-N intake was greater for CMEC and RPS. Replacing solvent-extracted canola meal with the high-oil meal decreased milk fat 12:0, 14:0, 16:0, and total saturated FA content and enhanced cis-9 18:1 and total monounsaturated FA concentrations. Relative to the CTRL, canola increased total trans FA in milk, whereas inclusion of HOLL in the diet increased trans-11 18:1 and cis-9, trans-11 CLA content. The RPS increased milk fat cis-13 22:1 content from 0.07 to 2.33 g/100g of FA. In conclusion, HOLL or RPS, which are likely to come from small-scale biodiesel plants where oil is cold pressed without hexane extraction, fed at levels at or above 12 to 13% of dietary DM may decrease feed intake and milk production, but can be used to alter milk FA composition in lactating dairy cows.


Assuntos
Ração Animal , Brassica rapa , Bovinos/fisiologia , Ácidos Graxos Monoinsaturados/farmacologia , Ácidos Graxos/análise , Lactação/efeitos dos fármacos , Leite/metabolismo , Rúmen/efeitos dos fármacos , Ração Animal/análise , Animais , Brassica rapa/química , Dieta/veterinária , Ácidos Graxos Monoinsaturados/análise , Feminino , Fermentação/efeitos dos fármacos , Fermentação/fisiologia , Lactação/fisiologia , Leite/química , Valor Nutritivo , Óleo de Brassica napus , Rúmen/fisiologia
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