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1.
J Cachexia Sarcopenia Muscle ; 14(1): 198-213, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36398408

RESUMO

BACKGROUND: Chronic mTORC1 activation in skeletal muscle is linked with age-associated loss of muscle mass and strength, known as sarcopenia. Genetic activation of mTORC1 by conditionally ablating mTORC1 upstream inhibitor TSC1 in skeletal muscle accelerates sarcopenia development in adult mice. Conversely, genetic suppression of mTORC1 downstream effectors of protein synthesis delays sarcopenia in natural aging mice. mTORC1 promotes protein synthesis by activating ribosomal protein S6 kinases (S6Ks) and inhibiting eIF4E-binding proteins (4EBPs). Whole-body knockout of S6K1 or muscle-specific over-expression of a 4EBP1 mutant transgene (4EBP1mt), which is resistant to mTORC1-mediated inhibition, ameliorates muscle loss with age and preserves muscle function by enhancing mitochondria activities, despite both transgenic mice showing retarded muscle growth at a young age. Why repression of mTORC1-mediated protein synthesis can mitigate progressive muscle atrophy and dysfunction with age remains unclear. METHODS: Mice with myofiber-specific knockout of TSC1 (TSC1mKO), in which mTORC1 is hyperactivated in fully differentiated myofibers, were used as a mouse model of sarcopenia. To elucidate the role of mTORC1-mediated protein synthesis in regulating muscle mass and physiology, we bred the 4EBP1mt transgene or S6k1 floxed mice into the TSC1mKO mouse background to generate 4EBP1mt-TSC1mKO or S6K1-TSC1mKO mice, respectively. Functional and molecular analyses were performed to assess their role in sarcopenia development. RESULTS: Here, we show that 4EBP1mt-TSC1mKO, but not S6K1-TSC1mKO, preserved muscle mass (36.7% increase compared with TSC1mKO, P < 0.001) and strength (36.8% increase compared with TSC1mKO, P < 0.01) at the level of control mice. Mechanistically, 4EBP1 activation suppressed aberrant protein synthesis (two-fold reduction compared with TSC1mKO, P < 0.05) and restored autophagy flux without relieving mTORC1-mediated inhibition of ULK1, an upstream activator of autophagosome initiation. We discovered a previously unidentified phenotype of lysosomal failure in TSC1mKO mouse muscle, in which the lysosomal defect was also conserved in the naturally aged mouse muscle, whereas 4EBP1 activation enhanced lysosomal protease activities to compensate for impaired autophagy induced by mTORC1 hyperactivity. Consequently, 4EBP1 activation relieved oxidative stress to prevent toxic aggregate accumulation (0.5-fold reduction compared with TSC1mKO, P < 0.05) in muscle and restored mitochondrial homeostasis and function. CONCLUSIONS: We identify 4EBP1 as a communication hub coordinating protein synthesis and degradation to protect proteostasis, revealing therapeutic potential for activating lysosomal degradation to mitigate sarcopenia.


Assuntos
Alvo Mecanístico do Complexo 1 de Rapamicina , Sarcopenia , Animais , Camundongos , Modelos Animais de Doenças , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Sarcopenia/genética , Sarcopenia/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
2.
Childs Nerv Syst ; 38(7): 1371-1375, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34609612

RESUMO

BACKGROUND: Neurophysiological brainstem mapping techniques facilitate the intra-operative localisation of cranial nerve nuclei amidst distorted anatomy. Neurophysiological recording in young infants can be limited due to immature myelination and synaptogenesis, as well as an increased sensitivity to anaesthetic agents. CASE REPORT: A 5-month-old boy was diagnosed with a cystic brainstem lesion located dorsally within the pons and upper medulla. An open surgical biopsy was undertaken via a posterior fossa craniotomy, revealing a grossly distorted fourth ventricular floor. Intra-operative neurophysiological mapping produced oculomotor, facial, glossopharyngeal and vagal muscle responses allowing a deviated functional midline to be identified. Direct stimulation was used to identify an area in the floor of the fourth ventricle eliciting no cranial nerve responses and allow safe entry into the tumour cavity and biopsy. Transcranial motor evoked responses (TcMEPs), short-latency somatosensory evoked potentials (SSEPs) and brainstem auditory evoked potentials (BAEPs) were all successfully recorded throughout the procedure, despite the use of halogenated gaseous anaesthesia. CONCLUSIONS: We describe the use of brainstem mapping techniques for identification of a distorted midline on the floor of the 4th ventricle in an infant, with reproducible recordings of intra-operative TcMEPs, SSEPs and BAEPs.


Assuntos
Potenciais Somatossensoriais Evocados , Quarto Ventrículo , Tronco Encefálico/cirurgia , Nervos Cranianos , Potencial Evocado Motor , Potenciais Somatossensoriais Evocados/fisiologia , Quarto Ventrículo/cirurgia , Humanos , Lactente , Masculino , Ponte
3.
Bone ; 153: 116134, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34332160

RESUMO

AIM: To investigate the associations between indices of bone health in childhood and corresponding parental measures. METHODS: The Southampton Women's Survey characterised 12,583 non-pregnant women aged 20-34 years; 3158 subsequently had singleton live births. In a subset, dual-energy X-ray absorptiometry (DXA) measurements of bone area (BA), bone mineral content (BMC) and areal bone mineral density (aBMD) lumbar spine and total hip were obtained in the parent/offspring (aged 8-9 years) trios. Another subset of children (aged 6-7 years), and their parents, had peripheral quantitative computed tomography (pQCT; 4% and 38% tibia) measures. Using multivariable linear regression we examined relationships between mother/father and offspring, adjusting for parental age, habitual walking speed and education; offspring age and sex; and the corresponding bone measure in the other parent (ß-coefficients (95%CI) unit/unit for each bone measure). RESULTS: Data were available for 260 trios with DXA and 99 with pQCT. There were positive associations for BA, BMC and aBMD between either parent and offspring. Mother-child associations were of greater magnitude than father-child; for example, mother-child aBMD (ß = 0.26 g·cm-2/g·cm-2 (0.21,0.32)) and father-child aBMD (ß = 0.16 g·cm-2/g·cm-2 (0.11,0.21)), P-difference in ß = 0.007. In the subset with pQCT there was a positive association for mother-offspring 4% tibial total area (ß = 0.33 mm2/mm2 (0.17,0.48)), but little evidence of a father-offspring association (ß = -0.06 mm2/mm2 (-0.17,0.06)). In contrast offspring 38% cortical density was more strongly associated with this measure in fathers (ß = 0.48 mg·cm-3/mg·cm-3 (0.15,0.82)) than mothers (ß = 0.27 mg·cm-3/mg·cm-3 (-0.03,0.56)). In general mother-father differences were attenuated by adjustment for height. CONCLUSIONS: Whilst offspring bone measures are independently associated with those of either parent, the magnitude of the association is often greater for maternal than paternal relationships. These findings are consistent with an in utero influence on offspring growth but might also reflect genetic and/or epigenetic parent of origin effects. SUMMARY: In an established parent-offspring cohort, associations between parent and offspring bone indices were generally greater in magnitude for mother-offspring than father-offspring relationships.


Assuntos
Densidade Óssea , Osso e Ossos , Absorciometria de Fóton , Osso e Ossos/diagnóstico por imagem , Feminino , Humanos , Vértebras Lombares , Relações Pais-Filho
4.
J Dairy Sci ; 103(1): 846-851, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31733865

RESUMO

Ectoparasitic stable flies (Stomoxys calcitrans [L.]), horn flies (Haematobia irritans [L.]), and face flies (Musca autumnalis De Geer) negatively affect dry matter intake, milk production, and health of pastured dairy cows. These flies cause fly avoidance behaviors and are a major welfare concern for dairy producers. The objective of this study was to evaluate the effects of mesh Shoofly Leggins (Stone Manufacturing & Supply, Kansas City, MO) on fly avoidance behaviors and numbers of flies attacking pastured dairy cows. In a crossover design, lactating dairy cows (n = 80) were randomly assigned to groups with and without leggings (Shoofly Leggins worn on all legs). All cows were managed in one group. Cows were observed for 2-wk periods, and then treatments were reversed in the next 2-wk interval. Counts of stable flies, horn flies, and face flies on all cows were recorded twice daily (once in morning per cow: 0930 to 1230 h; and once in the afternoon per cow: 1330 to 1630 h), 3 times per wk on Tuesday, Wednesday, and Thursday of each week during the study period. The total number of flies per cow was greater on cows with leggings than cows without leggings. The number of horn flies per cow was greater on cows in with leggings (26.4 flies/side) compared with cows without leggings (24.1 flies/side). Stable fly numbers were similar for cows with and without leggings (12.8 flies/leg). A random subset of 20 focal cows per group was observed during 5-min intervals to record frequencies of 4 behaviors: leg stomps, head tosses, skin twitches, and tail swishes. Counts of head tosses (2.6 vs. 3.1), skin twitches (20.9 vs. 19.6), and tail swishes (21.3 vs. 19.3) were similar for cows without leggings versus cows with leggings, respectively. However, foot stomps were 39% lower for cows with leggings compared with cows without leggings, and leg stomps were 26% higher in the afternoon than in the morning (2.9 vs. 2.4, respectively). A positive correlation was observed between stable and horn flies and all insect avoidance behaviors. Numbers of stable flies were 1.5 times greater in the afternoon than in the morning. The results of this study indicated that flies were associated with cow fly avoidance behaviors regardless of the use of leggings, but leggings effectively reduced foot stomps by 39%, so their use may provide some relief from stable fly injury to pastured dairy cows.


Assuntos
Doenças dos Bovinos/parasitologia , Ectoparasitoses/veterinária , Muscidae , Roupa de Proteção/veterinária , Animais , Aprendizagem da Esquiva , Comportamento Animal , Bovinos , Doenças dos Bovinos/prevenção & controle , Estudos Cross-Over , Ectoparasitoses/prevenção & controle , Feminino , Lactação
5.
J Dairy Sci ; 102(11): 10606-10615, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31477309

RESUMO

The objective of this study was to evaluate the effects of 2 winter (December to April) housing systems on dairy cow hygiene scores, frostbite, teat condition, clinical mastitis, and activity and rumination across 3 winter seasons (2013, 2014, and 2015). Certified-organic cows (n = 268) were randomly assigned to 2 treatments (2 replicates per system): (1) outdoor straw pack (outdoor) or (2) 3-sided compost-bedded pack barn (indoor). Cows calved during 2 seasons (spring or fall) at the University of Minnesota West Central Research and Outreach Center, Morris, Minnesota, organic dairy. Organic wheat straw was used as bedding for the 2 outdoor straw packs, and bedding was maintained by farm management to keep cows dry and absorb manure throughout the winter. The compost-bedded pack barn (2 pens in the barn) was bedded with organic-approved sawdust, and the bedding material was stirred twice per day with a small chisel plow. Hygiene scores were recorded biweekly as cows exited the milking parlor. Incidence of clinical mastitis was recorded in a binary manner as treated (1) or not treated (0) at least once during a lactation. Frostbite incidence was collected monthly. Activity and rumination times (daily and 2-h periods) were monitored electronically using a neck collar sensor (HR-LD Tags, SCR Dairy, Netanya, Israel). Indoor cows had greater udder hygiene scores (1.75 vs. 1.46) and greater abdomen hygiene scores (1.79 vs. 1.43) compared with outdoor cows. Additionally, the indoor cows had greater upper and lower leg hygiene scores compared with outdoor cows. Incidence of clinical mastitis was greater for indoor cows compared with outdoor cows (27.1% vs. 15.1%, respectively). Frostbite incidence was not different between indoor (30.1%) and outdoor (17.5%) cows. Daily rumination was 509 min/d for indoor cows and 530 min/d for the outdoor cows. In summary, lactating cows housed outdoors on straw-bedded packs had cleaner udders and improved udder health compared with cows housed in a compost-bedded pack barn.


Assuntos
Doenças dos Bovinos/prevenção & controle , Indústria de Laticínios , Congelamento das Extremidades/veterinária , Abrigo para Animais , Glândulas Mamárias Animais/fisiologia , Ruminação Digestiva , Animais , Bovinos , Feminino , Congelamento das Extremidades/prevenção & controle , Higiene , Israel , Lactação , Leite , Minnesota , Estações do Ano
6.
Nat Commun ; 10(1): 632, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30733432

RESUMO

To reveal how cells exit human pluripotency, we designed a CRISPR-Cas9 screen exploiting the metabolic and epigenetic differences between naïve and primed pluripotent cells. We identify the tumor suppressor, Folliculin(FLCN) as a critical gene required for the exit from human pluripotency. Here we show that FLCN Knock-out (KO) hESCs maintain the naïve pluripotent state but cannot exit the state since the critical transcription factor TFE3 remains active in the nucleus. TFE3 targets up-regulated in FLCN KO exit assay are members of Wnt pathway and ESRRB. Treatment of FLCN KO hESC with a Wnt inhibitor, but not ESRRB/FLCN double mutant, rescues the cells, allowing the exit from the naïve state. Using co-immunoprecipitation and mass spectrometry analysis we identify unique FLCN binding partners. The interactions of FLCN with components of the mTOR pathway (mTORC1 and mTORC2) reveal a mechanism of FLCN function during exit from naïve pluripotency.


Assuntos
Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Via de Sinalização Wnt/fisiologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/fisiologia , Linhagem Celular , Estrona/genética , Estrona/metabolismo , Humanos , Imunoprecipitação , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Proteômica , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Via de Sinalização Wnt/genética
7.
J Dairy Sci ; 102(1): 706-714, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30343929

RESUMO

Certified-organic dairy cows (n = 268) were used to evaluate the effect of 2 winter (December to April) housing systems on milk production, somatic cell score (SCS), body weight, body condition score (BCS), and economics across 3 winter seasons (2013, 2014, and 2015). Bedding cultures from the housing systems were also evaluated. Cows were randomly assigned to 2 treatments (2 replicates per group): (1) outdoor (straw pack, n = 140) or (2) indoor (3-sided compost bedded pack barn, n = 128). Cows calved during 2 seasons (spring or fall) at the University of Minnesota West Central Research and Outreach Center, Morris, Minnesota, organic dairy. Milk, fat, and protein production and SCS were recorded from monthly milk recording. Body weight and BCS were recorded biweekly as cows exited the milking parlor. Bedding cultures from the housing systems were collected biweekly. Costs for key inputs and the price received for milk production were recorded for the study period and averaged for use in the profitability analysis. Energy-corrected milk and SCS were not different for the outdoor (15.1 kg/d, 2.64) and indoor (15.7 kg/d, 2.57) housing systems, respectively. In addition, cows in the outdoor and indoor housing systems were not different for body weight (528 vs. 534 kg) and BCS (3.22 vs. 3.23), respectively. Daily dry matter intake was 19.1 kg/d for the outdoor cows and 19.6 kg/d for indoor cows. The total bacteria count from bedding samples tended to be lower in the outdoor (13.0 log10 cfu/mL) compared with the indoor (14.9 log10 cfu/mL) system. Milk revenue and feed cost were not different for the 2 housing systems. Labor and bedding costs were lower and net return was higher for the outdoor housing system. The outdoor straw pack system had a $1.42/cow per day net return advantage over the indoor compost bedded pack barn. In summary, lactating cows housed outdoors on straw-bedded packs did not differ for production or SCS, or for body weight, BCS, or dry matter intake, but had greater profitability than cows housed in an indoor compost bedded pack barn.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios/economia , Abrigo para Animais , Lactação/fisiologia , Agricultura Orgânica/métodos , Estações do Ano , Ração Animal/economia , Animais , Roupas de Cama, Mesa e Banho/economia , Roupas de Cama, Mesa e Banho/microbiologia , Peso Corporal , Contagem de Células/veterinária , Custos e Análise de Custo , Indústria de Laticínios/métodos , Ingestão de Alimentos , Feminino , Leite/química , Leite/citologia , Leite/economia , Minnesota
8.
Mymensingh Med J ; 27(2): 429-436, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29769515

RESUMO

Complications in paediatric anaesthesia can be conveniently classified as minor or major. Major morbidity includes cardiac arrest, brain damage and death. Minor morbidity can be assessed by clinical audits with smell patient samples. Major morbidity is rare. It is best assessed by very large clinical studies and by review of cases malpractice claims. Both minor & major complication occurs most commonly in infants and children under three especially those with severe co-morbidities. Knowledge of risk profiles in paediatric anaesthesia is a starting point for the reduction of risk complication.


Assuntos
Anestesia Geral , Parada Cardíaca , Imperícia , Anestesia Geral/efeitos adversos , Criança , Parada Cardíaca/etiologia , Humanos , Lactente , Morbidade
9.
Undersea Hyperb Med ; 45(2): 199-208, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29734572

RESUMO

INTRODUCTION: Patients with prior primary spontaneous pneumothorax (PSP) frequently seek clearance to dive. Despite wide consensus in precluding compressed-air diving in this population, there is a paucity of data to support this decision. We reviewed the literature reporting the risk of PSP recurrence. METHODS: A literature search was performed in PubMed and Web of Science using predefined terms. Studies published in English reporting the recurrence rate after a first PSP were included. RESULTS: Forty studies (n=3,904) were included. Risk of PSP recurrence ranged 0-67% (22 ± 15.5%; mean ± SD). Mean follow-up was 36 months, and 63 ± 39% of recurrences occurred during the first year of follow-up. Elevated height/weight ratio and emphysema-like changes (ELCs) are associated with PSP recurrence. ELCs are present in 59%-89% (vs. 0-15%) of patients with recurrence and can be detected effectively with high-resolution CT scan (sensitivity of 84-88%). Surgical pleurodesis reduces the risk of recurrence substantially (4.0 ± 4% vs. 22 ± 15.5%). CONCLUSION2: Risk of PSP recurrence seems to decline over time and is associated to certain radiological and clinical risk factors. This could be incremented by the stresses of compressed-air diving. A basis for informed patient-physician discussions regarding future diving is provided in this review.


Assuntos
Mergulho/efeitos adversos , Pneumotórax/etiologia , Estatura , Peso Corporal , Humanos , Pleurodese , Pneumotórax/diagnóstico por imagem , Pneumotórax/cirurgia , Pneumotórax/terapia , Enfisema Pulmonar/complicações , Enfisema Pulmonar/diagnóstico por imagem , Recidiva , Fatores de Risco , Prevenção Secundária , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
10.
J Dairy Sci ; 101(5): 4667-4675, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29501334

RESUMO

The objective of this study was to evaluate the efficacy of a commercial vacuum fly trap (CowVac, Spalding Laboratories, Reno, NV) in on-farm organic dairy production systems to control horn flies, stable flies, and face flies. As cows walk through the trap, flies are brushed off the face, flank, and back with hanging flaps and blown off the belly, udder, and legs from one side, and then vacuumed from the air into a chamber from vacuum inlets opposite the blower and above the cow. The study included 8 organic dairy farms during the summer of 2015 in Minnesota, and herds ranged from 30 to 350 cows in size. The farms were divided into pairs by location; during the first period of the summer (June to July), the trap was set up on 1 farm, whereas during the second period of the summer (August to September) the trap was sent to its paired farm. Farms were visited once per week to collect and count flies from the trap as well as count and record flies on cows. Bulk tank milk, fat, and protein production and somatic cell count were collected on farms during the entire study period. Data were analyzed using the GLM procedure of SAS (version 9.3, SAS Institute Inc., Cary, NC). Independent variables for analyses were the fixed effects of farm, trap presence, housing scenario, and summer period. Horn fly numbers on cows were lower by 44% on farm in the presence of a trap (11.4 vs. 20.5 flies/cow-side) compared with the absence of a trap. Stable fly (5.4 vs. 7.1 flies/leg) and face fly (1.0 vs. 1.0 flies/cow) numbers were similar on farm whether the trap was present or absent on farms, respectively. Milk production was similar for farms with the trap (15.5 kg/d) compared to without (15.3 kg/d) the trap. Bulk tank milk, milk components, and somatic cell count were statistically similar in the presence and absence of the trap, so potential benefits of the trap for those measures were not evident at low fly populations observed during the study. The presence of a trap on farm reduced horn fly population growth rates (-1.01 vs. 1.00 flies/d) compared with the absence of a trap. Cows on farms with no housing (100% pasture) tended to have reduced horn fly numbers (11.7 vs. 28.3 flies/cow-side) in the presence of a trap compared with the absence of a trap on farm. Cows on farms with housing had similar horn fly numbers (11.2 vs. 14.8 flies/cow-side) in the presence of a trap compared with the absence of a trap on farm. In summary, these results indicate the trap was effective in reducing horn fly numbers on cows and reduced horn fly growth rates during the pasture season in organic dairy production systems, but benefits in improved milk production were not evident likely because of relatively low fly populations.


Assuntos
Bovinos/microbiologia , Dípteros/crescimento & desenvolvimento , Controle de Insetos/métodos , Animais , Bovinos/metabolismo , Bovinos/parasitologia , Indústria de Laticínios , Feminino , Controle de Insetos/instrumentação , Masculino , Leite/metabolismo , Minnesota , Agricultura Orgânica , Estações do Ano , Vácuo
11.
Oncogene ; 36(22): 3119-3136, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28092677

RESUMO

Aberrant regulation of WNT/ß-catenin signaling has a crucial role in the onset and progression of cancers, where the effects are not always predictable depending on tumor context. In melanoma, for example, models of the disease predict differing effects of the WNT/ß-catenin pathway on metastatic progression. Understanding the processes that underpin the highly context-dependent nature of WNT/ß-catenin signaling in tumors is essential to achieve maximal therapeutic benefit from WNT inhibitory compounds. In this study, we have found that expression of the tumor suppressor, phosphatase and tensin homolog deleted on chromosome 10 (PTEN), alters the invasive potential of melanoma cells in response to WNT/ß-catenin signaling, correlating with differing metabolic profiles. This alters the bioenergetic potential and mitochondrial activity of melanoma cells, triggered through regulation of pro-survival autophagy. Thus, WNT/ß-catenin signaling is a regulator of catabolic processes in cancer cells, which varies depending on the metabolic requirements of tumors.


Assuntos
Melanoma/metabolismo , Mitocôndrias/metabolismo , PTEN Fosfo-Hidrolase/genética , Via de Sinalização Wnt , beta Catenina/metabolismo , Animais , Humanos , Masculino , Melanoma/enzimologia , Melanoma/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , PTEN Fosfo-Hidrolase/metabolismo
12.
J Dairy Sci ; 99(12): 9942-9948, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27692720

RESUMO

The objectives of this study were to evaluate activity, rumination time, and their association with 3 kinds of pasture flies for organic dairy cows (n=57) fed 3 grain supplementation strategies during the grazing season from May to September 2013. Cows were assigned to 1 of 3 replicate supplementation groups: (1) no corn-grain supplementation (100% pasture, PAS, n=19); (2) low corn-grain (2.72kg/cow per day, LG, n=19); and (3) high corn-grain (5.44kg/cow per day, HG, n=19). Cows calved during 2 seasons (fall and spring) at the University of Minnesota West Central Research and Outreach Center, Morris, from October to December 2012 and March to May 2013. Supplement (corn-grain and minerals) was fed in a total mixed ration of corn silage and alfalfa silage, and at least 30% of diet dry matter intake for LG and HG cows consisted of pasture. Activity and rumination time (daily and 2-h blocks of time) were monitored electronically using HR-LD tags (SCR Engineers Ltd., Netanya, Israel) for 125d. Activity (cow body movement and head movement) was reported in activity units from SCR DataFlow II software, and rumination times were reported in minutes per day. PROC HPMIXED in SAS (SAS Institute Inc., Cary, NC) was used for statistical analysis, and independent variables were season of calving (fall or spring), month of grazing (June to September), supplementation group, and interactions of month of grazing and supplementation group. Replicate was a random effect with repeated measures. Daily activity was higher for PAS cows (1,138 activity units) than for HG cows (1,001 activity units), and LG cows (1,019 activity units). Daily activity was highest in July (1,258 activity units) and lowest in September (819 activity units). Rumination was not different for PAS (397min/d), LG (384min/d), or HG (370min/d) cows. Daily rumination was greater in September (402min/d) than in July (361min/d). Daily activity increased rapidly between 0600-0800h and 1600-1800h. From 1800 to 2000h, cows had a rapid decline in activity until 0600h the next day. All supplementation groups had the greatest rumination activity from 0200 to 0400h and the least between 1000 and 1200h. Greater activity of cows on a herd basis was moderately correlated with increased fly populations. Monthly activity patterns of grazing cows were associated with fly populations on cows.


Assuntos
Bovinos/fisiologia , Digestão , Atividade Motora , Muscidae/fisiologia , Silagem/análise , Zea mays/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Indústria de Laticínios/métodos , Dieta/veterinária , Suplementos Nutricionais/análise , Grão Comestível/química , Feminino , Controle de Insetos , Minnesota , Densidade Demográfica
13.
J Appl Physiol (1985) ; 121(4): 953-964, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27633739

RESUMO

Diving narcosis results from the complex interaction of gases, activities, and environmental conditions. We hypothesized that these interactions could be separated into their component parts. Where previous studies have tested single cognitive tasks sequentially, we varied inspired partial pressures of CO2, N2, and O2 in immersed, exercising subjects while assessing multitasking performance with the Multi-Attribute Task Battery II (MATB-II) flight simulator. Cognitive performance was tested under 20 conditions of gas partial pressure and exercise in 42 male subjects meeting U.S. Navy age and fitness profiles. Inspired nitrogen (N2) and oxygen (O2) partial pressures were 0, 4.5, and 5.6 ATA and 0.21, 1.0, and 1.22 ATA, respectively, at rest and during 100-W immersed exercise with and without 0.075-ATA CO2 Linear regression modeled the association of gas partial pressure with task performance while controlling for exercise, hypercapnic ventilatory response, dive training, video game frequency, and age. Subjects served as their own controls. Impairment of memory, attention, and planning, but not motor tasks, was associated with N2 partial pressures >4.5 ATA. Sea level O2 at 0.925 ATA partially rescued motor and memory reaction time impaired by 0.075-ATA CO2; however, at hyperbaric pressures an unexpectedly strong interaction between CO2, N2, and exercise caused incapacitating narcosis with amnesia, which was augmented by O2 Perception of narcosis was not correlated with actual scores. The relative contributions of factors associated with diving narcosis will be useful to predict the effects of gas mixtures and exercise conditions on the cognitive performance of divers. The O2 effects are consistent with O2 narcosis or enhanced O2 toxicity.


Assuntos
Dióxido de Carbono/sangue , Mergulho/efeitos adversos , Oxigenoterapia Hiperbárica/efeitos adversos , Narcose por Gás Inerte/fisiopatologia , Óxido Nítrico/sangue , Oxigênio/metabolismo , Desempenho Psicomotor , Adulto , Pressão Atmosférica , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Humanos , Narcose por Gás Inerte/etiologia , Masculino , Pessoa de Meia-Idade , Movimento , Adulto Jovem
14.
J Am Mosq Control Assoc ; 32(2): 83-90, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27280346

RESUMO

An adult mosquito survey was conducted at 12 sites using carbon dioxide traps in northern Minnesota throughout the summer of 2012. Specimens were counted, identified to species, sorted into pools, and tested for eastern equine encephalitis (EEEV) and West Nile virus (WNV). Our findings extend the known range of Culiseta melanura, Anopheles barberi, and An. quadrimaculatus and document the presence and abundance of 27 other mosquito taxa in the region. None of the pools tested positive for EEEV or WNV.


Assuntos
Culicidae/fisiologia , Culicidae/virologia , Vírus da Encefalite Equina do Leste/isolamento & purificação , Insetos Vetores/fisiologia , Insetos Vetores/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Distribuição Animal , Animais , Biodiversidade , Feminino , Minnesota , Densidade Demográfica , Estações do Ano
15.
J Dairy Sci ; 99(4): 3183-3192, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26830734

RESUMO

The objective of this study was to describe and compare husbandry practices on organic and conventional dairy farms of similar sizes in Minnesota. Organic (ORG, n=35), same-sized conventional (SC, n=15, <200 cows) and medium-sized conventional (MC, n=13, ≥200 cows) dairy herds were visited in 2012, and farmers were interviewed once about their farm, herd demographics, and herd management practices concerning nutrition, housing, and reproductive programs. Organic farms had been established as long as conventional farms, and ORG producers had most commonly selected ORG farming because of a negative perception of pesticides for human health. The distribution of cattle breeds and ages differed across farm types. Organic farms had more crossbred cows and a greater number of older cows than conventional farms, who had mainly Holstein cattle. Organic farms did not dock tails, were more likely to use breeding bulls, and were less likely to conduct pregnancy diagnoses in cattle. All conventional farmers fed corn, corn silage, and hay, but no forage or feed supplement was fed by all ORG farms with the exception of pasture. Kelp was supplemented on most ORG farms but on none of the conventional farms. In summary, although there were differences across farm types regarding the use of pasture, feeds, and feed additives, breed and age distribution, reproductive management, and the use of tail docking, observations in other management areas showed large overlap across herd types.


Assuntos
Bovinos , Indústria de Laticínios/métodos , Agricultura Orgânica , Animais , Cruzamento , Doenças dos Bovinos , Dieta/veterinária , Feminino , Abrigo para Animais , Masculino , Minnesota , Gravidez , Reprodução , Silagem , Zea mays
17.
Osteoporos Int ; 27(2): 809-13, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26286627

RESUMO

UNLABELLED: Fracture history is an important component of osteoporosis diagnosis in children. One in six parentally reported lifetime fractures in children were not confirmed on review of radiographs. Care should be taken to avoid unnecessary investigations for possible osteoporosis due to parental over-reporting of soft tissue injuries as fractures. INTRODUCTION: The diagnosis of osteoporosis in children requires either a vertebral compression fracture, or a significant fracture history (defined as ≥2 long bone fractures <10 years or ≥3 long bone fractures <19 years, excluding high impact fractures) and low bone mineral density. As children with frequent fractures might benefit from further evaluation, we determined whether parental reports of lifetime fracture were accurate compared to radiological reports and if they appropriately selected children for further consideration of osteoporosis. METHODS: Parents of children (<18 years) with a musculoskeletal injury completed a questionnaire on their child's fracture history, including age, site and mechanism of previous fracture(s). Radiological reports were reviewed to confirm the fracture. RESULTS: Six hundred sixty parents completed the questionnaire and reported 276 previous fractures in 207 children. An injury treated at our hospital was recorded in 214 of the 276 parentally reported fractures. Thirty-four of 214 (16 %) were not a confirmed fracture. An injury was recorded for all parentally reported fractures in 150 children, but for 21 % children, there were inaccurate details (no evidence of fracture, incorrect site or forgotten fractures) on parent report. Eighteen of 150 children had a significant fracture history on parental report alone, but following review of radiology reports, 2 of 18 (11 %) did not have clinically significant fracture histories. CONCLUSIONS: Approximately one in six fractures reported by parents to have occurred in their child's lifetime had not resulted in a fracture. One in nine children with a significant fracture history could have been investigated unnecessarily.


Assuntos
Anamnese/normas , Rememoração Mental , Osteoporose/diagnóstico , Fraturas por Osteoporose/diagnóstico , Pais/psicologia , Adolescente , Criança , Pré-Escolar , Inglaterra , Feminino , Humanos , Lactente , Masculino , Fraturas por Osteoporose/psicologia , Seleção de Pacientes , Recidiva , Procedimentos Desnecessários/estatística & dados numéricos
18.
J Econ Entomol ; 108(4): 1728-38, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26470314

RESUMO

Western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), is a native, univoltine pest of corn and dry beans in North America. The current degree-day model for predicting a specified percentage of yearly moth flight involves heat unit accumulation above 10°C after 1 May. However, because the moth's observed range has expanded into the northern and eastern United States, there is concern that suitable temperatures before May could allow for significant S. albicosta development. Daily blacklight moth catch and temperature data from four Nebraska locations were used to construct degree-day models using simple or sine-wave methods, starting dates between 1 January and 1 May, and lower (-5 to 15°C) and upper (20 to 43.3°C) developmental thresholds. Predicted dates of flight from these models were compared with observed flight dates using independent datasets to assess model performance. Model performance was assessed with the concordance correlation coefficient to concurrently evaluate precision and accuracy. The best model for predicting timing of S. albicosta flight used simple degree-day calculations beginning on 1 March, a 3.3°C (38°F) lower threshold, and a 23.9°C (75°F) upper threshold. The revised cumulative flight model indicated field scouting to estimate moth egg density at the time of 25% flight should begin when 1,432 degree-days (2,577 degree-days °F) have accumulated. These results underscore the importance of assessing multiple parameters in phenological models and utilizing appropriate assessment methods, which in this case may allow for improved timing of field scouting for S. albicosta.


Assuntos
Voo Animal , Modelos Biológicos , Mariposas/fisiologia , Distribuição Animal , Animais , Feminino , Masculino , Nebraska
19.
20.
J Dairy Sci ; 98(5): 3143-51, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25726119

RESUMO

The objective of this study was to describe the prevalence and practices used to manage internal helminth parasites and external arthropod parasites on organic and conventional dairy herds in Minnesota. All organic (ORG) dairy herds in Minnesota (n=114) and a convenience sample of conventional herds were invited to participate in the study. Thirty-five ORG herds and 28 conventional herds were visited once in summer and fall of 2012. Conventional dairy herds were split into small conventional (SC,<200 cows) and medium-sized conventional herds (MC, ≥200 cows) so that SC herds were comparable in size to the ORG herds. Dairy managers were surveyed to assess their farm management practices and perceptions about parasites, hygiene scores were recorded for adult stock, and fecal samples were collected from a nominal 20 breeding-age heifers to characterize abundance of internal parasites. Nonparametric tests were used to compare fecal egg counts per gram (FEC) among farms grouped by management systems and practices. Organic farms had more designated pasture and were more likely to use rotational grazing compared with conventional farms, but the stocking densities of animals on pasture were similar among farm types. The overall FEC were very low, and only a few individual ORG heifers had FEC >500 eggs/gram. Samples from heifers on ORG farms had significantly more strongyle-type eggs than those on SC and MC farms (ORG: 6.6±2.1; SC: 0.5±0.3; MC: 0.8±0.7), but egg counts of other types of gastrointestinal parasites did not differ significantly among the 3 herd groups. Fly control measures were applied mainly to milking cows and preweaned calves and were used on 88.6% of ORG herds, 60.0% of SC herds, and 91.7% of MC herds. Approximately half of the producers reported having seen skin conditions suggestive of lice or tail mange in their cattle during the previous winter (ORG: 48.6%, SC: 57.1%, MC: 53.9%). Although most conventional producers reported treating these skin conditions, most organic producers stated they had not treated them. In conclusion, gastrointestinal parasite egg counts were low overall at the time of the survey, and most surveyed producers did not perceive gastrointestinal parasites to be a problem for their animals' health. Independent of the herd type, fly control was mostly targeted at the lactating herd and preweaned calves.


Assuntos
Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/parasitologia , Indústria de Laticínios/métodos , Agricultura Orgânica/métodos , Animais , Artrópodes , Bovinos , Doenças dos Bovinos/epidemiologia , Ectoparasitoses/epidemiologia , Ectoparasitoses/prevenção & controle , Ectoparasitoses/veterinária , Fezes/parasitologia , Feminino , Trato Gastrointestinal/parasitologia , Helmintos , Abrigo para Animais , Lactação , Leite , Minnesota , Contagem de Ovos de Parasitas/veterinária , Dermatopatias/parasitologia , Dermatopatias/veterinária
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