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1.
Mol Carcinog ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695604

RESUMO

Cancer vaccines strive to induce robust, antigen-targeted, T-cell-mediated immune responses but have struggled to produce meaningful regression in solid tumors. An autologous cell vaccine, SQZ-PBMC-HPV, was developed by SQZ Biotechnologies using microfluidic squeezing technology to load PBMCs with HPV16 E6 and E7 antigens in HLA-A*02+ patients. The SQZ-PBMC-HPV-101 Phase 1 trial (NCT04084951) enrolled patients with incurable HPV16+ cancers. Here, we present a post hoc analysis of the relationship between Posttreatment CD8+ T cell infiltration and patient outcomes. SQZ-PBMC-HPV was administered as monotherapy every 3 weeks. Tumor samples were collected pre-dose and post-dose 4 weeks after treatment start. Biomarkers including CD8, MHC-I, E6, E7, GZMB, and Ki67 were evaluated by immunohistochemistry, immunofluorescence, and RNA in situ hybridization, and were correlated with clinical response, survival, and drug product composition. Eighteen patients had paired pre- and post-dose biopsies. Six (33%) had an increase in CD8+ T cell density in tumor parenchyma between screening and C2D8. Patients with increased CD8+ T cell density had improved disease control rate (66.7% vs 16.7%) and median overall survival (606.5 days vs 170.0 days, p = 0.0078). Drug product was significantly enriched for higher T cells and lower monocytes in the increased CD8+ T cell density group. In patients with incurable HPV16+ solid tumors treated with SQZ-PBMC-HPV, an increase in CD8+ T cell density within the tumor parenchyma was associated with superior disease control rate and overall survival. The product composition for patients with increased CD8+ T cell density was enriched for T cells.

2.
Reprod Domest Anim ; 58(10): 1359-1367, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37573132

RESUMO

During the sheep breeding season, ovulatory follicles vary widely in age at pessary removal impacting both the timing of oestrus and pregnancy rates following artificial insemination (AI). Ovulatory follicles that emerge between days 7 to 9 of the pessary period are associated with higher fertility whilst those that emerge earlier or later are associated with lower fertility. In this study, two strategies to improve the success of AI by controlling the development of the ovulatory follicle were examined. In the first, ewes were treated with PGF2α at either -12 and/or +6 days (experiment 1) or -27 days (experiment 2) relative to pessary insertion to control the time of emergence of the ovulatory follicle. In the second, ewes were treated with eCG (400 IU per ewe) at either 0 h, -6 h or -12 h relative to pessary removal (experiment 3) to improve the development of young ovulatory follicles. PGF2α administered on day -27 increased the percentage of pregnant ewes by 17.8% and the number of foetuses per 100 ewes inseminated by 33.9%. PGF2α treatment at other times had either no effect or reduced fertility. During the breeding season, treatment with eCG at -12 h improved the synchrony of oestrus, reduced the size of the ovulatory follicle but did not improve pregnancy rate compared with other treatments. Treatment had no effect during the non-breeding season, supporting earlier findings that the quality of young ovulatory follicles differs during the year. In conclusion, PGF2α treatment 27 days before pessary insertion provides a new and cheap strategy to improve the success of fixed-time AI programs.

3.
J Natl Compr Canc Netw ; 19(8): 922-927, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34116502

RESUMO

BACKGROUND: The NCCN Guidelines for Older Adult Oncology recommend that, when possible, older adults with cancer undergo a geriatric assessment (GA) to provide a comprehensive health appraisal to guide interventions and appropriate treatment selection. However, the association of age with GA-identified impairments (GA impairments) remains understudied and the appropriate age cutoff for using the GA remains unknown. PATIENTS AND METHODS: We designed a cross-sectional study using the Cancer and Aging Resilience Evaluation (CARE) registry of older adults with cancer. We included adults aged ≥60 years diagnosed with gastrointestinal malignancy who underwent a patient-reported GA prior to their initial consultation at the gastrointestinal oncology clinic. We noted the presence of GA impairments and frailty using Rockwood's deficit accumulation approach. We studied the relation between chronologic age and GA impairments/frailty using Spearman rank correlation and chi-square tests of trend. RESULTS: We identified 455 eligible older adults aged ≥60 years with gastrointestinal malignancies; the median age was 68 years (range, 64-74 years) and colorectal (33%) and pancreatic (24%) cancers were the most common cancer type. The correlation between chronologic age and number of geriatric impairments was weak and did not reach statistical significance (Spearman ρ, 0.07; P=.16). Furthermore, the prevalence of domain-specific impairments or frailty was comparable across the 3 age groups (60-64 years, 65-74 years, ≥75 years) with the exception of comorbidity burden. Notably, 61% of patients aged 60 to 64 years had ≥2 GA impairments and 35% had evidence of frailty, which was comparable to patients aged 65 to 74 years (66% and 36%, respectively) and ≥75 years (70% and 40%, respectively). CONCLUSIONS: Using chronologic age alone to identify which patients may benefit from GA is problematic. Future studies should identify screening tools that may identify patients at high risk of frailty and GA impairments.


Assuntos
Fragilidade , Neoplasias Gastrointestinais , Neoplasias , Idoso , Estudos Transversais , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/epidemiologia , Avaliação Geriátrica , Humanos , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Sistema de Registros
4.
Mol Reprod Dev ; 84(9): 883-896, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28628264

RESUMO

Lactation anoestrus limits the flexibility of modern pig production systems such that any increase in lactation length reduces farrowing frequency, and thus profit. This review focuses on post-partum development of the sow's reproductive system, the physiology of lactation anoestrus and how it can be overcome, as well as the fertility of sows mated while lactating. The propensity for sows to ovulate spontaneously while lactating is high (24-31%), and a high proportion of sows will ovulate rapidly and synchronously in response to combinations of altered suckling (split weaning, interrupted suckling), daily boar contact, exogenous gonadotrophins, and group housing. The apparent ease with which lactation anoestrus can be overcome represents an opportunity to uncouple sow mating from weaning, thus reducing the impact of lactation length on productivity. This is especially true when considering the benefits of the described stimulation methods on the reproductive performance (i.e., shorter weaning to oestrus intervals and higher litter sizes) of the low proportion of sows that maintain lactation anoestrus.


Assuntos
Sincronização do Estro/métodos , Estro , Lactação , Animais , Feminino , Masculino , Suínos
5.
Lancet ; 386(9988): 63-73, 2015 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-25907157

RESUMO

BACKGROUND: Individuals with a history of recurrent depression have a high risk of repeated depressive relapse or recurrence. Maintenance antidepressants for at least 2 years is the current recommended treatment, but many individuals are interested in alternatives to medication. Mindfulness-based cognitive therapy (MBCT) has been shown to reduce risk of relapse or recurrence compared with usual care, but has not yet been compared with maintenance antidepressant treatment in a definitive trial. We aimed to see whether MBCT with support to taper or discontinue antidepressant treatment (MBCT-TS) was superior to maintenance antidepressants for prevention of depressive relapse or recurrence over 24 months. METHODS: In this single-blind, parallel, group randomised controlled trial (PREVENT), we recruited adult patients with three or more previous major depressive episodes and on a therapeutic dose of maintenance antidepressants, from primary care general practices in urban and rural settings in the UK. Participants were randomly assigned to either MBCT-TS or maintenance antidepressants (in a 1:1 ratio) with a computer-generated random number sequence with stratification by centre and symptomatic status. Participants were aware of treatment allocation and research assessors were masked to treatment allocation. The primary outcome was time to relapse or recurrence of depression, with patients followed up at five separate intervals during the 24-month study period. The primary analysis was based on the principle of intention to treat. The trial is registered with Current Controlled Trials, ISRCTN26666654. FINDINGS: Between March 23, 2010, and Oct 21, 2011, we assessed 2188 participants for eligibility and recruited 424 patients from 95 general practices. 212 patients were randomly assigned to MBCT-TS and 212 to maintenance antidepressants. The time to relapse or recurrence of depression did not differ between MBCT-TS and maintenance antidepressants over 24 months (hazard ratio 0·89, 95% CI 0·67-1·18; p=0·43), nor did the number of serious adverse events. Five adverse events were reported, including two deaths, in each of the MBCT-TS and maintenance antidepressants groups. No adverse events were attributable to the interventions or the trial. INTERPRETATION: We found no evidence that MBCT-TS is superior to maintenance antidepressant treatment for the prevention of depressive relapse in individuals at risk for depressive relapse or recurrence. Both treatments were associated with enduring positive outcomes in terms of relapse or recurrence, residual depressive symptoms, and quality of life. FUNDING: National Institute for Health Research (NIHR) Health Technology Assessment (HTA) programme, and NIHR Collaboration for Leadership in Applied Health Research and Care South West Peninsula.


Assuntos
Antidepressivos/uso terapêutico , Terapia Cognitivo-Comportamental/métodos , Transtorno Depressivo Maior/prevenção & controle , Atenção Plena/métodos , Adulto , Idoso , Antidepressivos/administração & dosagem , Terapia Combinada , Transtorno Depressivo Maior/tratamento farmacológico , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Recidiva , Método Simples-Cego , Fatores Socioeconômicos , Resultado do Tratamento , Adulto Jovem
6.
Anim Reprod Sci ; 262: 107434, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368653

RESUMO

Increasing piglet weaning age while maintaining the reproductive efficiency of the breeding herd depends on being able to stimulate sows to ovulate during lactation without reducing subsequent pregnancy rates and litter sizes. Embryo survival is affected by the quality of the oocytes shed at ovulation, and oocyte quality is profoundly impacted by the follicular environment in which the oocyte matures. This study determined the effect of reducing suckled litter size from 11 to 7 piglets on day 18 of lactation on the ovarian follicular environment and oocyte developmental competence at day 21 of lactation. Thirty-nine, Large White X Landrace sows (parity 3.2 ± 0.2; mean ± SEM; range 2-6) had their litter size either maintained at 11 piglets (control); or reduced to seven piglets on day 18 of lactation (split wean (SW)). Sows were slaughtered on day 21 of lactation and ovaries were collected for analysis of follicular fluid composition and in vitro blastocyst development rates. There was no effect of split weaning on fertilisation rate and development to blastocyst stage; however, a greater proportion of blastocysts from control sows were classified as early blastocyst stage. Furthermore, follicular fluid concentrations of oestradiol were higher in SW sows. Together, these results indicate split weaning prior to mating in lactation alters the ovarian follicular environment and while blastocyst development rates were unaffected, embryos from control sows may be of poorer quality as indicated by a delay in development.


Assuntos
Lactação , Reprodução , Gravidez , Suínos , Animais , Feminino , Desmame , Paridade , Tamanho da Ninhada de Vivíparos , Oócitos
7.
Anim Reprod Sci ; 263: 107440, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38452579

RESUMO

Increasing piglet weaning age while maintaining the reproductive efficiency of the breeding herd depends on the ability to stimulate sows to ovulate during lactation without reducing subsequent pregnancy rates and litter sizes. The aim of this study was to determine if a reduction in piglet suckling load, either prior to or immediately after mating in lactation, altered ovarian follicle development and increased embryo survival to day 30 of gestation. Fifty-nine multiparous Large White x Landrace sows were allocated to one of three treatments; litter size maintained at 11 piglets (control); litter size reduced to seven piglets on day 18 of lactation (split wean (SW)); or litter size reduced to seven piglets at expression of lactation oestrus (oestrus split wean (OES SW)). The percentage of sows that expressed lactation oestrus did not differ between treatments (79.7 %; P > 0.05) and split weaning had minimal effects on ovarian follicle development. Pregnancy rates were higher for SW and OES SW sows, compared to control sows. Embryo survival to day 30 of gestation was higher for SW sows (73.7 %) compared with control (56.4 %) and OES SW sows (49.5 %; P < 0.05). In summary, weaning a portion of the litter prior to mating in lactation improved pregnancy rates and embryo survival.


Assuntos
Lactação , Reprodução , Gravidez , Animais , Feminino , Suínos , Desmame , Taxa de Gravidez , Tamanho da Ninhada de Vivíparos , Paridade
8.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38285624

RESUMO

Diets that provide a negative dietary anion cation difference (DCAD) and supplement with a vitamin D metabolite 25-OH-D3 (calcidiol) may increase calcium availability at parturition, and enhance piglet survival and performance. This factorial study assessed the effects of DCAD, calcidiol (50 µg/kg), and parity (parity 1 or >1) and their interactions. Large White and Landrace sows (n = 328), parity 1 to 8 were randomly allocated in blocks to treatment diets from day 103 of gestation until day 3 postfarrow: 1) negative DCAD without calcidiol (negative DCAD + no CA), n = 84, 2) negative DCAD with calcidiol (negative DCAD + CA) n = 84, 3) positive DCAD without calcidiol (negative DCAD + no CA), n = 81, and 4) positive DCAD with calcidiol (positive DCAD + CA), n = 79. Negative DCAD diets were acidified with an anionic feed (2 kg/t) and magnesium sulfate (2 kg/t). All treatment diets contained cholecalciferol at 1,000 IU/kg. Dry sow diets contained 14.8% crude protein (CP), 5.4% crude fiber (CF), 0.8% Ca, and 83 mEq/kg DCAD. Treatment diets 1 and 2 contained 17.5% CP, 7.3% CF, 0.8% Ca, and -2 mEq/kg DCAD. Treatment diets 3 and 4 contained 17.4% CP, 7.4% CF, 0.8% Ca, and 68 mEq/kg DCAD. Before farrowing, all negative DCAD sows had lower urine pH than all sows fed a positive DCAD (5.66 ± 0.05 and 6.29 ± 0.05, respectively; P < 0.01); urinary pH was acidified for both DCAD treatments indicating metabolic acidification. The percentage of sows with stillborn piglets was not affected by DCAD, calcidiol, or parity alone but sows fed the negative DCAD + CA diet had a 28% reduction in odds of stillbirth compared to the negative DCAD + no CA diet and even lesser odds to the positive DCAD + CA diet. At day 1 after farrowing, blood gas, and mineral and metabolite concentrations were consistent with feeding a negative DCAD diet and that negative DCAD diets influence energy metabolism, as indicated by increased glucose, cholesterol, and osteocalcin concentrations and reduced nonesterified free fatty acids and 3-hydroxybutyrate concentrations. In the subsequent litter, total piglets born and born alive (14.7 ± 0.3 and 13.8 ± 0.3 piglets, respectively; P = 0.029) was greater for positive DCAD diets compared to negative DCAD diets; and there was an interaction between DCAD, calcidiol, and parity (P = 0.002). Feeding a negative DCAD diet influenced stillbirth, subsequent litter size, and metabolic responses at farrowing. More studies are needed to define optimal diets prefarrowing for sows.


The transition period between late gestation and lactation is critical to farrowing and successful lactation; sows with higher blood calcium have less risk of dystocia. We evaluated transition diets that provided a negative dietary cation­anion difference (DCAD) and supplemented with calcidiol (CA), both of which influence calcium metabolism. Purebred Landrace or Large White sows (n = 328) were enrolled in the experiment and selected sows that were either primiparous (n = 99) or multiparous (n = 229; average parity = 2.59 ± 1.51; parity range = 1 to 8) were fed a dry sow ration until day 103 of gestation and were then fed transition diets until day 3 postfarrowing in a factorial study. The diets were formulated to include 1) negative DCAD + no CA, 2) negative DCAD + CA, 3) positive DCAD + no CA, or 4) positive DCAD + CA. All diets induced a metabolic acidosis as indicated by urinary pH. Sows fed the negative DCAD with added calcidiol had a >28% reduction in odds of stillbirth over negative DCAD + no CA and positive DCAD + CA diets. Following weaning and re-mating, there were 0.9 more piglets born in the subsequent litter for both positive DCAD diets compared to negative DCAD diets. Blood gas, and mineral and metabolite concentrations provided evidence that negative DCAD diets positively influenced energy metabolism.


Assuntos
Calcifediol , Doenças dos Suínos , Gravidez , Feminino , Animais , Suínos , Natimorto/veterinária , Lactação , Dieta/veterinária , Suplementos Nutricionais , Ânions/metabolismo , Cátions/metabolismo , Ração Animal/análise
9.
Anim Reprod Sci ; 265: 107477, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38663150

RESUMO

The success of fixed - time artificial insemination (AI) in the ewe is variable due to poor synchrony of estrus. We examined the effects of long-term nutrition (LTN; low, medium, high - 6 months), short-term nutrition (STN; 1.0 M, 1.5 M - 14 days) and progesterone supplementation (P; single pessary, replacement on Day 9) on synchrony and reproductive outcomes. High LTN advanced (P < 0.05) estrus, increased (P = 0.06) pregnancy (range 71.1 - 81.1%) and improved (P < 0.01) litter size (range 1.30 - 1.50). STN increased (P < 0.05) pregnancy (79.0 versus 72.3%) but not litter size or timing of estrus. A LTN x STN interaction (P < 0.01) for time of estrus indicates that the effects of LTN were moderated by STN depending on the level of LTN. Pessary replacement delayed (P < 0.05) the onset of estrus, improved synchrony but did not affect pregnancy or litter size. High LTN increased (P < 0.05) the number of large (≥ 3.8 mm) and medium - size follicles (2.0 - 3.7 mm) but the diameter of large follicles tended to be reduced (P = 0.08) on Day 12. STN did not affect follicle number or size whilst P reduced (P < 0.05) the diameter of large follicles on Day 12 (4.83 versus 5.10 mm) and increased the number of medium - size follicles (3.56 versus 2.74 mm). In conclusion, both LTN and STN are major sources of variability in AI programs whilst pessary replacement has potential to reduce variability.


Assuntos
Suplementos Nutricionais , Inseminação Artificial , Progesterona , Animais , Feminino , Progesterona/administração & dosagem , Progesterona/farmacologia , Inseminação Artificial/veterinária , Inseminação Artificial/métodos , Gravidez , Ovinos/fisiologia , Sincronização do Estro/métodos , Fenômenos Fisiológicos da Nutrição Animal , Ração Animal/análise , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Dieta/veterinária , Estro/efeitos dos fármacos , Estro/fisiologia , Fatores de Tempo
10.
Nat Food ; 5(3): 206-210, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38459392

RESUMO

Livestock heat stress threatens production, particularly in semi-arid, arid and tropical regions. Using established temperature thresholds for sheep, we modelled +1 °C and +3 °C temperature increases over the historical baseline, estimating that 2.1 million potential lambs are lost annually due to heat stress alone, increasing to 2.5 and 3.3 million, respectively, as temperatures rise. Heat stress poses risks at key periods of the reproductive cycle, with consequences across the Australian sheep flock.


Assuntos
Transtornos de Estresse por Calor , Ovinos , Animais , Gravidez , Feminino , Peso ao Nascer , Temperatura , Austrália/epidemiologia , Tamanho da Ninhada de Vivíparos , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico
11.
Theriogenology ; 197: 31-36, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36463668

RESUMO

Progesterone treatment for synchrony of estrus is standard in sheep artificial insemination (AI) programs but can be associated with poor outcomes. Potential for improvement exists through a better understanding of the interactions between follicle development, luteal regression, emergence of the ovulatory follicle and timing of estrus. These interactions were examined by comparing progesterone-treated (Day 1 = day of pessary insertion) and naturally cycling ewes (Day 1 = day after estrus) at three times of the year (Autumn, Spring equinox and late Spring). Observations were made from Day 1 until the day of ovulation. Compared with the natural cycle, progesterone treatment (300 mg intra-vaginal pessary for 14 d) reduced the number of follicle waves (2.2 ± 0.18 versus 2.8 ± 0.12; P < 0.05) and increased the length of the ovulatory wave (8.6 ± 0.45 versus 6.6 ± 0.42 d; P < 0.05). The number of follicles per wave, the inter-wave interval and ovulation rate were not affected. However, progesterone treatment induced (P < 0.05) an earlier luteolysis (9.7 ± 0.51 versus 15.4 ± 0.49 d after Day 1), an earlier emergence of the ovulatory follicle (7.5 ± 0.48 versus 11.4 ± 0.46 d after Day 1) and an earlier onset of estrus (26.1 ± 2.95 versus 53.3 ± 2.84 h after Day 14). Time of year also influenced the response to progesterone treatment. In Autumn compared with the Spring equinox and late Spring, there was a reduction (P < 0.05) in follicle wave number (2.4 ± 0.21 versus 2.5 ± 0.29 versus 3.0 ± 0.20 respectively), follicles per wave (2.6 ± 0.27 versus 3.5 ± 0.25 versus 3.2 ± 0.20 respectively), ovulation rate (1.6 ± 0.12 versus 1.9 ± 0.12 versus 2.0 ± 0.10 respectively) and the inter-wave interval was longer (5.3 ± 0.40 versus 4.0 ± 0.32 versus 3.8 ± 0.27 d respectively; P < 0.05). Time of year also influenced (P < 0.05) the time of luteolysis (earliest in late Spring), emergence of the ovulatory follicle (earliest in Autumn) and onset of estrus (earliest in Autumn). It is concluded that (1) the effects of progesterone treatment on follicle waves are relatively minor, (2) the effects of treatment on timing of luteolysis, emergence of the ovulatory follicle and onset of estrus are all significant although the effects on AI outcomes remain to be determined and (3) time of year has a minimal effect on follicle waves but a more significant effect on other parameters of the estrous cycle. A better understanding of these complexities will assist in the development of improved protocols for synchrony of estrus.


Assuntos
Pessários , Progesterona , Feminino , Animais , Ovinos , Progesterona/farmacologia , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Ciclo Estral , Estradiol/farmacologia , Ultrassonografia
12.
Head Neck ; 45(5): 1315-1326, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36859797

RESUMO

Salivary gland carcinomas (SGC) are a rare and variable group of head and neck cancers with historically poor response to cytotoxic chemotherapy and immunotherapy in the recurrent, advanced, and metastatic settings. In the last decade, a number of targetable molecular alterations have been identified in SGCs including HER2 upregulation, androgen receptor overexpression, Notch receptor activation, NTRK gene fusions, and RET alterations which have dramatically improved treatment outcomes in this disease. Here, we review the landscape of precision therapy in SGC including current options for systemic management, ongoing clinical trials, and promising future directions.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias das Glândulas Salivares , Humanos , Neoplasias das Glândulas Salivares/patologia , Imunoterapia , Fusão Gênica , Glândulas Salivares/patologia
13.
Theriogenology ; 202: 103-109, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36933284

RESUMO

This study extends observations on the effects of intra-vaginal progesterone treatment on the relationships between the time of luteolysis, emergence of the ovulatory follicle, timing of estrus and ewe fertility. Observations were made in progesterone - treated ewes in autumn, the spring equinox and late spring (Experiment 1, Data set 1) and in progesterone - treated ewes and naturally cycling ewes in autumn and the spring equinox (Experiment 1, Data set 2). In Data set 1, the day of emergence of both the first and second ovulatory follicle was positively related to the day luteal regression within each season. In turn, the day of emergence influenced the timing of estrus by means of a season by day of luteal regression interaction (P < 0.001) indicating that the relationship was positive in autumn and the spring equinox but negative in late spring. In autumn, older ovulatory follicles were associated with an earlier onset of estrus compared with younger ovulatory follicles. In late spring, this relationship was reversed and was influenced by whether or not ewes were cycling at the time of pessary insertion. In Data set 2, the relationship between the day of follicle emergence and luteal regression was influenced by a treatment by day of regression interaction indicating the relationship was positive in treated ewes and negative in naturally cycling ewes. Timing of estrus was positively related (P < 0.001) to both the day of luteal regression and the day of follicle emergence (P < 0.05), with both relationships being stronger in naturally cycling ewes than in treated ewes. In Experiment 2, pregnancy rate following artificial insemination in autumn was highest (90.2%) when luteolysis occurred during Days 7-9 of the pessary period compared with Days 1-6 (77.8%, P = 0.16), 10 to 12 (68.8%, P < 0.05) or Days ≥13 (71.2%, P < 0.05). Timing of estrus was not affected. The mean diameter of ovulatory follicles that emerged during Days 7-9 was larger on Day 12 (5.8 ± 0.13 mm) compared with other periods (range 4.7 ± 0.05 to 5.6 ± 0.14 mm). This study provides two potential strategies to improve the success of AI programs. Firstly, appropriately timed treatment with PGF2α to control the time of emergence of ovulatory follicles and, secondly, earlier treatment with eCG to improve the development of ovulatory follicles that emerge late in the pessary period. Each is likely to be influenced by season and the cyclical status of the ewe.


Assuntos
Inseminação Artificial , Folículo Ovariano , Progesterona , Ovinos , Feminino , Animais , Folículo Ovariano/fisiologia , Progesterona/farmacologia , Pessários/veterinária , Estro , Reprodução , Inseminação Artificial/veterinária , Modelos Lineares , Estações do Ano , Resultado da Gravidez/veterinária , Gravidez , Fatores de Tempo
14.
J Clin Transl Sci ; 7(1): e270, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38380392

RESUMO

Introduction: Most students in MD-PhD programs take a leave of absence from medical school to complete PhD training, which promotes a natural loss of clinical skills and knowledge and could negatively impact a student's long-term clinical knowledge. To address this concern, clinical refresher courses in the final year of PhD training have traditionally been used; however, effectiveness of such courses versus a longitudinal clinical course spanning all PhD training years is unclear. Methods: The University of Alabama at Birmingham MD-PhD Program implemented a comprehensive continuing clinical education (CCE) course spanning PhD training years that features three course components: (1) clinical skills; (2) clinical knowledge; and (3) specialty exposure activities. To evaluate course effectiveness, data from an anonymous student survey completed at the end of each semester were analyzed. Results: Five hundred and ninety-seven surveys were completed by MD-PhD students from fall 2014 to 2022. Survey responses indicated that the majority of students found the course helpful to: maintain clinical skills and knowledge (544/597, 91% and 559/597, 94%; respectively), gain exposure to clinical specialties (568/597, 95%), and prepare them for responsibilities during clinical clerkships. During semesters following lockdowns from the COVID-19 pandemic, there were significant drops in students' perceived preparedness. Conclusions: Positive student survey feedback and improved preparedness to return to clinic after development of the course suggests the CCE course is a useful approach to maintain clinical knowledge during research training.

15.
J Natl Cancer Inst ; 115(11): 1392-1403, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37389416

RESUMO

BACKGROUND: The programmed cell death protein 1 (PD-1) and programmed death ligand 1 (PD-L1) are validated cancer targets; however, emerging mechanisms and impact of PD-L1 intracellular signaling on cancer behavior are poorly understood. METHODS: We investigated the cancer cell intrinsic role of PD-L1 in multiple patient-derived models in vitro and in vivo. PD-L1 overexpression, knockdown, and PD-L1 intracellular domain (PD-L1-ICD) deletion (Δ260-290PD-L1) models were assessed for key cancer properties: clonogenicity, motility, invasion, and immune evasion. To determine how PD-L1 transduces signals intracellularly, we used the BioID2 platform to identify the PD-L1 intracellular interactome. Both human papillomavirus-positive and negative patient-derived xenografts were implanted in NOD-scid-gamma and humanized mouse models to investigate the effects of recombinant PD-1, anti-PD-L1, and anti-signal transducer and activator of transcription 3 (STAT3) in vivo. RESULTS: PD-L1 intracellular signaling increased clonogenicity, motility, and invasiveness in multiple head and neck squamous cell carcinoma (HNSCC) models, and PD-1 binding enhanced these effects. Protein proximity labeling revealed the PD-L1 interactome, distinct for unbound and bound PD-1, which initiated cancer cell-intrinsic signaling. PD-L1 binding partners interleukin enhancer binding factors 2 and 3 (ILF2-ILF3) transduced their effect through STAT3. Δ260-290PD-L1 disrupted signaling and reversed pro-growth properties. In humanized HNSCC in vivo models bearing T-cells, PD-1 binding triggered PD-L1 signaling, and dual PD-L1 and STAT3 inhibition were required to achieve tumor control. CONCLUSIONS: Upon PD-1 binding, the PD-L1 extracellular and intracellular domains exert a synchronized effect to promote immune evasion by inhibiting T-cell function while simultaneously enhancing cancer cell-invasive properties.


Assuntos
Antígeno B7-H1 , Neoplasias de Cabeça e Pescoço , Animais , Humanos , Camundongos , Neoplasias de Cabeça e Pescoço/genética , Camundongos Endogâmicos NOD , Receptor de Morte Celular Programada 1 , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
16.
J Natl Med Assoc ; 114(3): 251-257, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35232610

RESUMO

Among the many academic challenges faced by dual-degree MD-PhD students is access to professional support networks designed to overcome the unique academic and personal barriers to physician-scientist training. In the current study, we hypothesized that regional access to a student MD-PhD conference, termed the Southeastern Medical Scientist Symposium (SEMSS), would enhance medical and/or graduate training by fostering such relationships between physician-scientist trainees, doing so by discussing both the challenges of physician-scientist training and effective strategies to overcome them. In the current study, we used a mixed-methods approach to evaluate the overall usefulness of SEMSS over a ten-year period (2010-2020) to identify key areas of particular benefit to trainees. The authors used conference registration data to compile self-reported demographic and regional attendance, followed by a post-conference survey to gauge attendee satisfaction. Over the reporting period, SEMSS was attended by equivalent proportions of MD-PhD and undergraduate students, among which were a high-percentage of students from underrepresented minority (URM) groups relative to the national MD-PhD applicant pool; nearly one-third of URM students attendees later matriculated into MD-PhD programs, far exceeding the national MD-PhD matriculation rate. Among the benefits reported by students were "opportunities to network with peers" and opportunities to learn about the physician-scientist career track. Therefore, we therefore propose regional MD-PhD conferences as an effective model to promote diversity within the physician-scientist training pipeline.


Assuntos
Pesquisa Biomédica , Médicos , Escolha da Profissão , Educação de Pós-Graduação em Medicina/métodos , Humanos , Grupos Minoritários , Satisfação Pessoal
17.
Animals (Basel) ; 11(9)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34573506

RESUMO

Tryptophan indirectly increases plasma calcium levels, which may improve sow health, and melatonin production, which may improve piglet survival when supplemented during late gestation and lactation. It was hypothesised that tryptophan would increase piglet survival and increase sow circulating melatonin and calcium. Seventy-two multiparous (Landrace x Large White) sows were allocated to either control (0.16% tryptophan; n = 24), low tryptophan (0.42%; n = 24) or high tryptophan (0.56%; n = 24). Piglet viability measures consisted of weights, behaviour, meconium staining, rectal temperature, blood glucose and serum immunoglobulin G concentration. Blood samples collected from sows were analysed for melatonin (two daytime and three night-time samples; n = 17) and calcium (two samples pre- and post-farrowing; n = 14). Both tryptophan treatments increased piglet survival compared to the control group (p < 0.001). Tryptophan had no effect on piglet viability (p > 0.05) and no effect on sow plasma melatonin and calcium concentrations compared with the control group (p > 0.05) except at 21:00 when low tryptophan sows had higher melatonin concentration compared with high tryptophan (p = 0.011). Further research to understand the mediating effects of tryptophan (particularly 5-hydroxytryptophan) on piglet survival, including sow behaviour, is warranted.

18.
J Anim Sci Biotechnol ; 12(1): 26, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33583422

RESUMO

Heat stress significantly impairs reproduction of sheep, and under current climatic conditions is a significant risk to the efficiency of the meat and wool production, with the impact increasing as global temperatures rise. Evidence from field studies and studies conducted using environmental chambers demonstrate the effects of hot temperatures (≥ 32 °C) on components of ewe fertility (oestrus, fertilisation, embryo survival and lambing) are most destructive when experienced from 5 d before until 5 d after oestrus. Temperature controlled studies also demonstrate that ram fertility, as measured by rates of fertilisation and embryo survival, is reduced when mating occurs during the period 14 to 50 d post-heating. However, the contribution of the ram to heat induced reductions in flock fertility is difficult to determine accurately. Based primarily on temperature controlled studies, it is clear that sustained exposure to high temperatures (≥ 32 °C) during pregnancy reduces lamb birthweight and will, therefore, decrease lamb survival under field conditions. It is concluded that both ewe and ram reproduction is affected by relatively modest levels of heat stress (≥ 32 °C) and this is a concern given that a significant proportion of the global sheep population experiences heat stress of this magnitude around mating and during pregnancy. Despite this, strategies to limit the impacts of the climate on the homeothermy, behaviour, resource use and reproduction of extensively grazed sheep are limited, and there is an urgency to improve knowledge and to develop husbandry practices to limit these impacts.

19.
BMJ Open ; 10(2): e033892, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32075835

RESUMO

OBJECTIVES: This study aimed to describe the recovery journeys of people with a history of recurrent depression who took part in a psychosocial programme designed to teach skills to prevent depressive relapse (mindfulness-based cognitive therapy (MBCT)), alongside maintenance antidepressant medication (ADM). DESIGN: A qualitative study embedded within a multicentre, single blind, randomised controlled trial (the PREVENT trial). SETTING: Primary care urban and rural settings in the UK. PARTICIPANTS: 42 people who participated in the MBCT arm of the parent trial were purposively sampled to represent a range of recovery journeys. INTERVENTIONS: MBCT involves eight weekly group sessions, with four refresher sessions offered in the year following the end of the programme. It was adapted to offer bespoke support around ADM tapering and discontinuation. METHODS: Written feedback and structured in-depth interviews were collected in the 2 years after participants undertook MBCT. Data were analysed using thematic analysis and case studies constructed to illustrate the findings. RESULTS: People with recurrent depression have unique recovery journeys that shape and are shaped by their pharmacological and psychological treatment choices. Their journeys typically include several over-arching themes: (1) beliefs about the causes of depression, both biological and psychosocial; (2) personal agency, including expectations about their role in recovery and treatment; (3) acceptance, both of depression itself and the recovery journey; (4) quality of life; (5) experiences and perspectives on ADM and ADM tapering-discontinuation; and (6) the role of general practitioners, both positive and negative. CONCLUSIONS: People with recurrent depression describe unique, complex recovery journeys shaped by their experiences of depression, treatment and interactions with health professionals. Understanding how several themes coalesce for each individual can both support their recovery and treatment choices as well as health professionals in providing more accessible, collaborative, individualised and empowering care. TRIAL REGISTRATION NUMBER: Clinical trial number ISRCTN26666654; post results.


Assuntos
Antidepressivos/uso terapêutico , Terapia Cognitivo-Comportamental/métodos , Depressão/terapia , Transtorno Depressivo Maior/terapia , Atenção Plena , Adulto , Idoso , Antidepressivos/administração & dosagem , Atitude , Doença Crônica , Depressão/tratamento farmacológico , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/reabilitação , Feminino , Clínicos Gerais , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Psicoterapia de Grupo , Pesquisa Qualitativa , Qualidade de Vida , Recidiva , Método Simples-Cego , Reino Unido
20.
Animals (Basel) ; 10(10)2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32993073

RESUMO

Betaine increases the synthesis of creatine, an energy-rich amino acid that increases adenosine triphosphate (ATP) and has neuroprotective properties which may improve post-natal lamb survival. This study determined whether maternal betaine supplementation during gestation would improve body weight, thermoregulation, time to stand and suck, colostrum intake and survival to weaning of twin lambs. Twin-bearing Merino ewes received dietary betaine at either 0 g/day (Control, CTL), 2 g/day from ram introduction to parturition (Early betaine, EB) or 4 g/day from Day 80 of gestation to parturition (Late betaine, LB). Ewes were housed individually during parturition and measures were collected at 4, 24 and 72 h and Day 7 post-partum, and at marking (53.2 ± 0.2 days of age) and weaning (99.3 ± 0.2 days of age). The EB treatment resulted in heavier lambs at weaning compared with CTL and LB lambs (p < 0.05). Time to stand and suck from birth was longer in EB lambs (p < 0.05), whereas, the interval from birth to first suck was shorter for LB lambs (p < 0.05). Lamb survival rate was the highest for LB lambs at 72 h and Day 7 (p < 0.05), and lowest for EB lambs on Day 7 (p < 0.05). These data indicated that betaine supplementation at 4 g/day during the second half of pregnancy improved twin lamb survival to Day 7 and shortened the interval from birth to first suck; whereas feeding ewes 2 g/day of betaine for the duration of pregnancy increased twin lamb body weight at weaning, but increased both the time to attain behavioural milestones and mortalities before Day 7.

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