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PubMed2005

Age effect of broiler breeders on fertility and sperm penetration of the perivitelline layer of the ovum.

The objective of this study was to determine the age effect of a broiler breeder flock on duration of fertility and number of spermatozoa penetrating the perivitelline layer overlying the germinal disc (SP/mm(2) GDIPVL). Moreover, in the second half of the flock's reproductive life, the effect of using ejaculates of young roosters (CA2) in artificial insemination (AI) on the above parameters of fertility was estimated. The commercial flock of broiler breeder hens (n = 100) was inseminated six times from 31 to 62 weeks of age. Additional inseminations, with ejaculates of roosters aged 31 and 36 weeks (CA2), were performed at 56 and 62 weeks of age. AI was performed during two consecutive days (D0 and D1) with an insemination dose of 125 x 10(6) spermatozoa/0.06 ml containing pooled ejaculates. The following parameters were studied: the effective and maximum duration of fertility (De and Dm), percent of fertility on different days after AI (FD10, FD15 and FD20), indices of duration of sperm penetration (DSP, SP < or = 3/GDIPVL), SP/mm(2) GDIPVL in eggs laid on successive days after insemination of hens at different age, and correlations between some fertility indices. Both for De and Dm, the highest values were noted after AI of the layers at 36 weeks of age (14.8 +/- 0.49 and 17.4 +/- 0.46 days, respectively), which were about 2 days longer than at 56 weeks. All fertility indices decreased gradually with age, starting from AI at peak egg production (31-36 weeks of age), while the use of ejaculates from CA2 did not help to increase them significantly. Correlation coefficients between SP/mm(2) GDIPVL and the other fertility indices were positive and highest for eggs laid on D3. It is concluded that high De values can be obtained from broiler breeders in adequate environmental and technological conditions of AI. It is suggested that the age-related decrease in fertility is more pronounced in females, in which the efficiency of sperm storage tubules decreases. The present fertility indices indicate the possibility of lengthening AI intervals, especially at peak egg production.

Aging↗

PubMed2005

Conception rates and serum progesterone concentration in dairy cattle administered gonadotropin releasing hormone 5 days after artificial insemination.

The objectives of this study were to determine the effect of administration of exogenous GnRH 5days after artificial insemination (AI) on ovarian structures, serum progesterone concentration, and conception rates in lactating dairy cows. In experiment 1, 23 Holstein cows were synchronized using the Ovsynch protocol. Five days after AI (day 0) cows were assigned randomly to receive either saline (saline; n=11) or 100microg GnRH (GnRH; n=12). To examine ovarian structures, ultrasonography was performed on day 1 and every other day beginning on day 5 until day 13. On days 5 and 13 blood samples were obtained to measure serum progesterone concentrations. All cows in the GnRH-treated group developed an accessory corpus luteum (CL), whereas cows in the saline group did not. Mean serum progesterone concentrations did not differ between GnRH and saline groups on day 5 (1.64+/-0.46ng/ml versus 2.04+/-0.48ng/ml). On day 13 serum progesterone concentrations were greater (P<0.05) in the GnRH group compared with saline (5.22+/-0.46ng/ml versus 3.36+/-0.48ng/ml). In experiment 2, 542 lactating cows, at two different commercial dairies, were used to test the effect of administering GnRH 5 days after AI on conception rates. Cows were synchronized and detected for estrus according to tail chalk removal. Cows detected in estrus received AI within 1h after detection of estrus. Five days after AI, cows were assigned randomly to receive either GnRH (n=266) or saline (n=276). Pregnancy status was determined by palpation per rectum of uterine contents approximately 40 days after AI. There was no effect of farm on conception rate. There was no effect of treatment as conception rates did not differ between GnRH and saline groups (26.7% GnRH versus 24.3% saline). Regardless of treatment, days in milk, parity, milk yield, and number of services had no effect on the odds ratio of pregnancy. In summary, the results of this study indicated that GnRH administered 5 days after AI increased serum progesterone by developing an accessory CL but did not improve conception rates in dairy cattle.

Animals↗

PubMed2006

Relationship of pre-ovulatory follicle size, estradiol concentrations and season to pregnancy outcome in dairy cows.

This study was carried out to evaluate effects of pre-ovulatory follicle size, plasma concentrations of estradiol and progesterone, and season on pregnancy outcomes in dairy cows. Holstein cows (n = 144) were synchronized and inseminated (Ovsynch/TAI protocol) in two distinct periods (cold versus warm season). Blood samples were collected daily from AI (day 0) to day 8 and on days 15, 22, 29, 36 and 64 to measure progesterone and estradiol. Pregnancy diagnosis was performed at days 29, 43 and 64. The pre-ovulatory follicle size was larger and the plasma estradiol concentrations on the day of AI were greater in animals that became pregnant. Plasma progesterone concentrations diverged and became greater after day 5 post-AI, in cows diagnosed pregnant, as compared to non-pregnant cows. The overall pregnancy rate (33%) or late embryonic/early fetal losses (23%) did not differ between seasons, but plasma estradiol concentrations on the day of AI and plasma concentrations of progesterone in pregnant cows were lower in the warm season. Reduced CL function, measured as plasma progesterone concentrations, from days 22 or 29 post-AI onward for cold and warm season, respectively, was associated with subsequent late embryonic/early fetal mortality. Overall, pregnancy was related to diameter of the pre-ovulatory follicle and plasma E2 on the day of AI, but embryonic/fetal losses were not. Season did not affect these outcomes, even though it influenced luteal function after AI.

Abortion, Veterinary↗

PubMed2026

The application of artificial intelligence in healthcare practice: A mapping review of systematic reviews.

Artificial intelligence (AI) is rapidly transforming healthcare practice, with growing evidence supporting its use in diagnosis, prognosis, treatment planning, and operational decision-making. The proliferation of systematic reviews in recent years underscores the need for an updated synthesis of the literature to inform research, policy, and practice. We searched PubMed, Web of Science, Scopus, IEEE Xplore, and CINAHL for systematic reviews and meta-analyses published between 2019 and February 2026. Eligible reviews focused on AI applications in healthcare practice, were peer-reviewed, and written in English. A total of 368 reviews met the inclusion criteria. Publication volume increased steadily, peaking in 2025. AI research was concentrated in high-density domains, such as radiology, oncology, and critical care. Across reviews, diagnostic imaging, electronic health record (EHR) data, and biomarkers/laboratory results accounted for 68% of training data sources, though newer data types, such as wearable device and sensor data, emerged from 2022 onward. Diagnosis, prognosis, and treatment comprised over 80% of AI applications, with novel uses emerging in recent years, such as AI-assisted clinical documentation (e.g., ambient documentation tools) and patient education. Ethical concerns were reported in 78.5% of reviews, with privacy, model accuracy, data and algorithmic bias, and explainability as recurrent themes. The proportion of reviews reporting ethical concerns increased from 2021 to 2025. AI applications in healthcare are expanding in scope, diversifying in data sources, and evolving toward novel clinical and operational uses. The human-centered AI or augmented intelligence paradigm, integrating computational precision with clinical expertise, holds significant promise but will require parallel advances in governance, regulatory frameworks, and ethical oversight to ensure safe adoption.

Artificial Intelligence↗

PubMed2004

Relationship between plasma lipid concentrations and HDL subclasses.

BACKGROUND: It is generally accepted that different high-density lipoprotein (HDL) subclasses have distinct but interrelated metabolic functions. HDL is known to directly influence the atherogenic process and changes in HDL subclasses distribution may be related to the incidence and prevalence of atherosclerosis. METHODS: Apo-AI contents(mg/l) of plasma HDL subclasses were determined by 2-dimensional gel electrophoresis coupled with immunodetection for apo-AI. Four hundred forty-two Chinese adults subjects aged 33 to 78 years were assigned to different groups according to the third Report of NCEP (ATP III) guidelines. The subjects were first divided into 2 groups, normal and high TG, then further classified by plasma TC, HDL-C and LDL-C concentrations. The subjects were also divided into TC desirable and TC high groups. RESULTS: Apo-A contents of prebeta(1)-HDL were higher while HDL(2b) were lower in high TG subjects vs. the corresponding normal TG subjects according to plasma TC and LDL-C concentrations. With the increase of plasma TC concentrations, apo-AI contents of prebeta(1)-HDL were significantly higher in high TC subgroup vs. TC desirable subgroup in normal TG subjects. With the decrease of HDL-C concentrations, apo-AI contents of HDL(2b) tended to decrease in normal TG subjects. And, with the increases of LDL-C concentration, in normal TG subjects, apo-AI contents of prebeta(1)-HDL and HDL(3b) were significantly higher and those of HDL(2b) were significantly lower in very high LDL-C subgroup vs. LDL-C optimal subgroup. On the other hand, apo-AI contents of prebeta(1)-HDL and HDL(3a) were significantly higher, while HDL(2a) and HDL(2b) were significantly lower in high TG and very high TG subgroup vs. normal TG subgroup within either TC desirable or TC high subjects. In a multivariate linear regression model, TG and TC concentrations were all associated independently and positively with high prebeta(1)-HDL; however, HDL-C were inversely associated with high prebeta(1)-HDL. And TG and TC concentrations were all associated independently and negatively with low HDL(2b), but HDL-C and apo-AI were positively associated with low HDL(2b). CONCLUSIONS: With the increase of plasma TG, TC, LDL-C or the decrease of plasma HDL-C concentrations, there was a general shift toward smaller-sized HDL, which, in turn, indicates that reverse cholesterol transport might be weakened and HDL maturation might be abnormal. Plasma TG concentration is a more important factor than TC concentration on the changes of HDL subclass distribution. Moreover, when TG is normal and HDL-C decreased, large-size HDL particles tended to decrease.

Adult↗

PubMedDate not supplied

Does academic intervention impact ABS qualifying examination results?

OBJECTIVES: To assess the impact of a focused academic support program on American Board of Surgery In-Training Examination (ABSITE) scores and Qualifying Examination (QE) outcomes. METHODS: A mandatory intervention program was begun in April 2001 for residents with ABSITE Total Test (TT) percentiles <31. Program elements included: 1) individual faculty mentoring and personal learning plan 2) QE videotape review sessions 3) Surgical Education and Self-Assessment Program (SESAP) 4) monthly rotation evaluations, and 5) quarterly status feedback. A free medical evaluation was offered. Mock orals participation, educational psychologist consultation, and voluntary followup mentoring were added later. Study data were reviewed for 2003-2005 Chief Residents including ABSITE scores, QE results, conference attendance, rotation Overall Performance ratings, and resident surgeon case volumes. Results were compared for the academic intervention (AI) and no intervention (NI) groups. RESULTS: Fifteen residents graduated during the study period. Eight residents completed nine interventions; seven returned to TT percentiles >30 (7/8, 88%). First post-intervention ABSITE gains were large compared to NI and national peer groups. Standard Score (SS) TT gains were maintained until residency completion by four AI residents. Median AI PGY-5 TT percentile was 32 and three scores were <or=25. Six AI residents (6/8, 75%) and all NI residents (7/7, 100%) passed the QE on their first attempts. AI and NI groups were similar for conference attendance, rotation evaluations, and operative log totals. CONCLUSIONS: A focused academic support intervention for residents with marginal ABSITE TT percentiles can produce immediate substantial gains. Gains are variably maintained through remaining residency years. PGY-5 TT percentiles <or=25, seen with three AI residents (3/8, 38%), are associated with a 40% first QE failure rate. Therefore, our 75% QE first-time pass rate for AI residents argues for intervention success.

Curriculum↗

PubMed2005

The influence of valve physiology on outcome following aortic valvotomy for congenital bicuspid valve in children: 30-year results from a single institution.

OBJECTIVE: Aortic valvotomy is widely used for the treatment of congenital aortic stenosis in children. We sought to evaluate whether the predominant post-valvotomy physiology, aortic insufficiency (AI) or aortic stenosis (AS) independently affected patient outcome. METHODS: From 1972-2002, 57 children with congenital aortic stenosis underwent valvotomy. We divided age-matched patients with residual lesions based on their predominant pathology into three groups: Group I (n=14), patients with moderate AI; Group II (n=14), patients with moderate AS, and Group III (n=14), patients with combined AI and AS. Fifteen patients with severe AI or mild residual lesions following valvotomy were excluded from analysis. RESULTS: mean freedom from aortic valve replacement (AVR) was 11.2+/-1.7 years in Group I and 21.5+/-3.9 years in Group II, P=0.05. AVR was required in 11 patients (79%) in Group I vs. only 5 (36%) in Group II, P=0.05. Group III was intermediate, with 9 (64%) requiring AVR. At the time of AVR, patients with aortic stenosis had significantly higher fractional shortening % than those with insufficiency or combined lesions, (Group 1: 38.2+/-7.9 vs. Group II: 46.3+/-5.5 vs. Group III: 39.2+/-3.7, P=0.007). Patients in Group II also had less severely dilated ventricles (mm) than those in the other groups, (Group 1: 50.2+/-12.5 vs. Group II: 39.5+/-8.3 vs. Group III: 49.0+/-8.1, P=0.030). CONCLUSIONS: patients with predominant AI following valvotomy are more likely to need AVR sooner than those with residual stenosis without AI. Therefore, cautious use of repeat valvotomy using maneuvers to avoid AI (small balloons), may prolong freedom from aortic valve replacement in those patients with significant residual AS.

Aortic Valve↗

PubMed2006

Intrathecal synthesis of anti-viral antibodies in pediatric patients.

INTRODUCTION: Detection of intrathecal synthesis of specific antibodies (antibody index (AI)) is an established method to prove cerebral viral infection. Experience on its clinical application in large patient groups, however, is sparse. METHODS: Retrospective analysis of pediatric patients with positive viral AI treated at RWTH Aachen University Hospital between 1999 and 2005. RESULTS: 63 patients were studied, including 14 with encephalitis, 12 with neuritis, nine with cerebral vasculitis, six with multiple sclerosis (MS), five with severe cephalgia, five with psychiatric symptoms, three with hearing loss, two with seizures, three with white matter diseases, two with movement disorders, one with meningococcal meningitis and one with sinus venous thrombosis. Seven had several positive AI among them only one patient with MS. Of the 51 patients with a single positive AI and not having MS, 16 showed a positive AI for herpes simplex-, 13 for varicella zoster-, nine for Epstein-Barr-, four for cytomegalo-, four for mumps-, three for rubella- and two for measles virus. Frequent combinations were varicella zoster virus (VZV) and vasculitis (n = 8), herpes simplex virus (HSV) and neuritis (n = 6), Epstein-Barr virus (EBV) (n = 5), respectively, VZV (n = 4) and encephalitis as wells as mumps virus (n = 2) and hearing loss. Matched polymerase chain reaction (PCR) and AI data were available in 25 patients. PCR was simultaneously positive in three cases only. DISCUSSION: AI testing identifies a similar spectrum of pathogens as known from cerebrospinal fluid (CSF) PCR studies. It complements the PCR and increases the chance for adequate diagnosis and treatment of patients with assumed cerebral viral infections.

Adolescent↗

PubMed2005

A thermodynamic study of mesophilic, thermophilic, and hyperthermophilic L-arabinose isomerases: the effects of divalent metal ions on protein stability at elevated temperatures.

To gain insight into the structural stability of homologous homo-tetrameric l-arabinose isomerases (AI), we have examined the isothermal guanidine hydrochloride (GdnHCl)-induced unfolding of AIs from mesophilic Bacillus halodurans (BHAI), thermophilic Geobacillus stearothermophilus (GSAI), and hyperthermophilic Thermotoga maritima (TMAI) using circular dichroism spectroscopy. The GdnHCl-induced unfolding of the AIs can be well described by a two-state reaction between native tetramers and unfolded monomers, which directly confirms the validity of the linear extrapolation method to obtain the intrinsic stabilities of these proteins. The resulting unfolding free energy (DeltaGU) values of the AIs as a function of temperature were fit to the Gibbs-Helmholtz equation to determine their thermodynamic parameters based on a two-state mechanism. Compared with the stability curves of BHAI in the presence and absence of Mn2+, those of holo GSAI and TMAI were more broadened than those of the apo enzymes at all temperatures, indicating increased melting temperatures (Tm) due to decreased heat capacity (DeltaGp). Moreover, the extent of difference in DeltaCp between the apo and holo thermophilic AIs is larger than that of BHAI. From these studies, we suggest that the metal dependence of the thermophilic AIs, resulting in the reduced DeltaCp, may play a significant role in structural stability compared to their mesophilic analogues, and that the extent of metal dependence of AI stability seems to be highly correlated to oligomerization.

Aldose-Ketose Isomerases↗

PubMed2005

Purification and characterization of an L-arabinose isomerase from an isolated strain of Geobacillus thermodenitrificans producing D-tagatose.

The araA gene, encoding l-arabinose isomerase (AI), from the thermophilic bacterium Geobacillus thermodenitrificans was cloned and expressed in Escherichia coli. Recombinant AI was isolated with a final purity of about 97% and a final specific activity of 2.10 U/mg. The molecular mass of the purified AI was estimated to be about 230 kDa to be a tetramer composed of identical subunits. The AI exhibited maximum activity at 70 degrees C and pH 8.5 in the presence of Mn2+. The enzyme was stable at temperatures below 60 degrees C and within the pH range 7.5-8.0. d-Galactose and l-arabinose as substrate were isomerized with high activities. Ribitol was the strongest competitive inhibitor of AI with a Ki of 5.5mM. The apparent Km and Vmax for L-arabinose were 142 mM and 86 U/mg, respectively, whereas those for d-galactose were 408 mM and 6.9 U/mg, respectively. The catalytic efficiency (kcat/Km) was 48 mM(-1)min(-1) for L-arabinose and 0.5mM(-1)min(-1) for D-galactose. Mn2+ was a competitive activator and increased the thermal stability of the AI. The D-tagatose yield produced by AI from d-galactose was 46% without the addition of Mn2+ and 48% with Mn2+ after 300 min at 65 degrees C.

Aldose-Ketose Isomerases↗

PubMed2005

Regulation of LuxPQ receptor activity by the quorum-sensing signal autoinducer-2.

The extracellular signaling molecule autoinducer-2 (AI-2) mediates quorum-sensing communication in diverse bacterial species. In marine vibrios, binding of AI-2 to the periplasmic receptor LuxP modulates the activity of the inner membrane sensor kinase LuxQ, transducing the AI-2 information into the cytoplasm. Here, we show that Vibrio harveyi LuxP associates with LuxQ in both the presence and absence of AI-2. The 1.9 A X-ray crystal structure of apoLuxP, complexed with the periplasmic domain of LuxQ, reveals that the latter contains two tandem Per/ARNT/Simple-minded (PAS) folds. Thus, although many prokaryotic PAS folds themselves bind ligands, the LuxQ periplasmic PAS folds instead bind LuxP, monitoring its AI-2 occupancy. Mutations that disrupt the apoLuxP:LuxQ interface sensitize V. harveyi to AI-2, implying that AI-2 binding causes the replacement of one set of LuxP:LuxQ contacts with another. These conformational changes switch LuxQ between two opposing enzymatic activities, each of which conveys information to the cytoplasm about the cell density of the surrounding environment.

Amino Acid Sequence↗

PubMed2005

Intrathecal neostigmine reduces the zymosan-induced inflammatory response in a mouse air pouch model via adrenomedullary activity: involvement of spinal muscarinic type 2 receptors.

Intrathecal (IT) injection of neostigmine (a cholinesterase inhibitor) has been reported to produce a significant anti-nociceptive effect in a number of inflammatory pain models. However, a potential anti-inflammatory effect of IT neostigmine in these models has not been investigated. In the present study, we have examined the 'anti-inflammatory effect of IT injection of neostigmine' (AI-NEO) using a standard mouse air pouch model by evaluating the effect of AI-NEO on zymosan-induced leukocyte migration and myeloperoxidase (MPO) release. IT neostigmine was found to suppress both leukocyte migration and MPO degranulation in a dose dependent manner. We then established which subtypes of cholinergic receptors were involved in this AI-NEO. IT pretreatment with atropine (a muscarinic receptor antagonist) but not hexamethonium (a nicotinic receptor antagonist) completely blocked the IT neostigmine anti-inflammatory effect. Subsequent experiments showed that IT pretreatment with methoctramine (a muscarinic type 2 (M2) receptor antagonist), but not pirenzepine (M1 receptor antagonist) or 4-DAMP (M3 receptor antagonist), suppressed the AI-NEO. We then evaluated whether adrenal glandular activity was important in the AI-NEO. Adrenalectomy significantly blocked the AI-NEO, while intraperitoneal pretreatment with the beta-adrenoceptor antagonist (propranolol), but not the corticosteroid antagonist (RU486) reversed AI-NEO. In conclusion, these results indicate that IT neostigmine facilitates the activation of spinal M2 receptors and this activation ultimately leads to release of adrenal catecholamines which contribute to the anti-inflammatory effect observed at the site of tissue inflammation.

Adrenal Cortex Hormones↗

PubMed2004

Effects of abnormal ovarian cycles during pre-service period postpartum on subsequent reproductive performance of high-producing Holstein cows.

The primary objective of this study was to investigate the effects of abnormal ovarian cycles during the pre-service postpartum period on subsequent reproductive performance of high-producing Holstein cows. The study was conducted in a commercial dairy farm with approximately 150 lactating cows, in a subtropical region of Japan. Animals were kept in free-stall barn, and fed a total mixed ration. Cows that calved from June 2001 to July 2002 were included in the study. Milk samples were collected twice weekly from 2 to 11 weeks postpartum, and progesterone concentrations in skim milk were determined by ELISA. After a voluntary waiting period of 40 days, cows detected in estrus were bred by artificial insemination (AI). Pregnancy was confirmed by palpation per rectum 40-70 days after AI. Out of a total of 91 cases, 39 (42.9%) had normal ovarian cycles (ovulation within 45 days after calving, followed by normal ovarian cycles), 32 (35.2%) had prolonged luteal phase (i.e. luteal activity for >20 days), and 12 (13.2%) had anovulation or delayed first ovulation (i.e. first ovulation did not occur until >45 days after calving). The remaining (8.8%) had other types of abnormalities. When compared with cows with a normal ovarian cycle, prolonged luteal phase cows had a lower 100 days AI submission rate, conception rate and pregnancy rate (84.2% versus 56.3%; P<0.05, 50% versus 16.7%; P<0.05 and 42.1% versus 9.4%; P<0.01, respectively), and longer intervals to first AI and to conception ( 67+/-6 days versus 98+/-7 days and 95+/-9 days versus 136+/-11 days; P<0.01 for each). Similarly, when compared with cows with normal ovarian cycles, those with anovulation had lower 100 days conception rate and pregnancy rate (50% versus 0%; P<0.05 and 42.1% versus 0%; P<0.01, respectively), and longer intervals to first AI and to conception ( 67+/-6 days versus 93+/-12 days; P<0.05 and 95+/-9 days versus 155+/-14 days; P<0.01, respectively). Survival analysis of the data for calving to conception interval showed that cows with prolonged luteal phase or anovulation were getting pregnant at a slower rate, and took longer to get pregnant than the cows with normal resumption of ovarian cyclicity postpartum. In conclusion, abnormal ovarian cycles during the pre-service period postpartum adversely affected reproductive performance, including AI submission rate, pregnancy rate, interval to first AI, and calving to conception interval in high-producing Holstein cows.

Animals↗

PubMed2005

Perspectives for artificial insemination and genomics to improve global swine populations.

Civilizations throughout the world continue to depend on pig meat as an important food source. Approximately 40% of the red meat consumed annually worldwide (94 million metric tons) is pig meat. Pig numbers (940 million) and consumption have increased consistent with the increasing world population (FAO 2002). In the past 50 years, research guided genetic selection and nutrition programs have had a major impact on improving carcass composition and efficiency of production in swine. The use of artificial insemination (AI) in Europe has also had a major impact on pig improvement in the past 35 years and more recently in the USA. Several scientific advances in gamete physiology and/or manipulation have been successfully utilized while others are just beginning to be applied at the production level. Semen extenders that permit the use of fresh semen for more than 5 days post-collection are largely responsible for the success of AI in pigs worldwide. Transfer of the best genetics has been enabled by use of AI with fresh semen, and to some extent, by use of AI with frozen semen over the past 25 years. Sexed semen, now a reality, has the potential for increasing the rate of genetic progress in AI programs when used in conjunction with newly developed low sperm number insemination technology. Embryo cryopreservation provides opportunities for international transport of maternal germplasm worldwide; non-surgical transfer of viable embryos in practice is nearing reality. While production of transgenic animals has been successful, the low level of efficiency in producing these animals and lack of information on multigene interactions limit the use of the technology in applied production systems. Technologies based on research in functional genomics, proteomics and cloning have significant potential, but considerable research effort will be required before they can be utilized for AI in pig production. In the past 15 years, there has been a coordinated worldwide scientific effort to develop the genetic linkage map of the pig with the goal of identifying pigs with genetic alleles that result in improved growth rate, carcass quality, and reproductive performance. Molecular genetic tests have been developed to select pigs with improved traits such as removal of the porcine stress (RYR1) syndrome, and selection for specific estrogen receptor (ESR) alleles. Less progress has been made in developing routine tests related to diseases. Major research in genomics is being pursued to improve the efficiency of selection for healthier pigs with disease resistance properties. The sequencing of the genome of the pig to identify new genes and unique regulatory elements holds great promise to provide new information that can be used in pig production. AI, in vitro embryo production and embryo transfer will be the preferred means of implementing these new technologies to enhance efficiency of pig production in the future.

Animals↗

PubMed2006

Influence of sire and sire breed (Gyr versus Holstein) on establishment of pregnancy and embryonic loss in lactating Holstein cows during summer heat stress.

Heat stress has negative effects on pregnancy rates of lactating dairy cattle. There are genetic differences in tolerance to heat stress; Bos taurus indicus (B. t. indicus) cattle and embryos are more thermotolerant than Bos taurus taurus (B. t. taurus). In the present study, the effects of sire and sire breed on conception and embryonic/fetal loss rates of lactating Holstein cows during the Brazilian summer were determined. In Experiment 1, cows (n=302) were AI after estrus detection or at a fixed-time with semen from one Gyr (B. t. indicus) or one Holstein sire (B. t. taurus). Pregnancy was diagnosed 80 days after AI. In Experiment 2, cows (n=811) were AI with semen from three Gyr and two Holstein sires. Pregnancy was diagnosed at 30-40 and at 60-80 days after AI. Cows diagnosed pregnant at the first examination but non-pregnant at the second were considered as having lost their embryo or fetus. Data were analyzed by logistic regression. The model considered the effect of sire within breed, sire breed, days postpartum, period of lactation, and AI type (AI after estrus versus fixed-time). There was no effect of the AI type, days postpartum or milk production on conception or embryonic loss rates. The use of Gyr bulls increased pregnancy rate when compared to Holstein bulls [9.1% (60/657) versus 5.0% (23/456), respectively, P=0.008; data from Experiments 1 and 2 combined]. Additionally, in Experiment 2, cows inseminated using semen from sire #4 (Gyr) had lower embryonic loss (10%) when compared with other B. t. indicus (35.3% and 40%) or B. t. taurus sires (18.2% and 38.5%, P=0.03). In conclusion, the use of B. t. indicus sires may result in higher conception rates in lactating Holstein cows during summer heat stress. Moreover, sire can affect embryonic loss and selection of bulls according to this criterion may result in higher parturition rates in lactating Holstein cows.

Abortion, Veterinary↗

PubMed2006

Prioritising veterinary medicines according to their potential indirect human exposure and toxicity profile.

Veterinary medicines are used widely in the United Kingdom (UK) to protect animal health, prevent economic loss, and to help ensure a safe food supply. Veterinary medicine active ingredients (AIs) have been detected in various environmental media, including surface and groundwater, suggesting the potential for indirect human exposure from such residues. To fully assess the potential level of such exposures and the resultant potential risks to humans from all veterinary medicine AIs would be resource intensive. This paper proposes a method for prioritising veterinary medicine AIs according to estimates of their potential for indirect human exposure via the environment and their toxicity profile, and demonstrates its feasibility using an initial set of 83 veterinary medicine AIs approved for use in the UK. Overall, 13 AIs were classified as 'High' priority for detailed risk assessment, 19 as 'Medium' priority, 5 as 'Low' priority, and 46 as 'Very low' priority. The veterinary medicine AIs classified as 'High' or 'Medium' priority for detailed risk assessment included 15 different chemical groups and 10 different therapeutic indications. Overall, the proposed prioritisation scheme was demonstrated to provide a scientifically robust and pragmatic means of assessing the relative priority of veterinary medicine AIs for further detailed risk assessment regarding human exposure. However, there remain a number of data gaps that, if filled, would improve the accuracy of the resultant prioritisation.

Animals↗

PubMed2004

Proliferation to apoptosis ratio as a prognostic marker in adenocarcinoma of uterine cervix.

OBJECTIVES: To determine the Mitotic Index (MI), Apoptotic Index (AI), the ratio of the two indices (MI/AI) in normal endocervical glands, adenocarcinoma in situ (AIS) and invasive adenocarcinoma of cervix, and to evaluate the relationship among these indices with various clinicopathological features. METHODS: The MI, AI and MI/AI ratio in cervical adenocarcinoma were evaluated based on: (1) cell morphology in hematoxylin and eosin-stained sections; (2) immunohistochemical study for Ki67 antigen and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL). Eighty cases of invasive adenocarcinoma and eighteen cases of adenocarcinoma in situ (AIS) adjacent to invasive adenocarcinoma were included. Adjacent normal endocervical epithelium in 26 cases of adenocarcinoma was included as control. RESULTS: The MI, AI and MI/AI in normal endocervical glands, AIS and invasive carcinomas showed statistically significant differences (P<0.001). A significant positive correlation was found between AI and MI, as assessed by morphological features (P<0.001) and immunohistochemistry (P=0.006). The MI/AI ratio, determined by morphology, significantly correlated with staging (P=0.023) and survival (P=0.0045). Multivariate survival analysis showed that both MI/AI ratio determined by morphology (P<0.001) and stage of tumor (P=0.03) had independent prognostic value in invasive adenocarcinoma. CONCLUSIONS: Tumor proliferation significantly correlated with apoptotic activity in cervical adenocarcinoma. The MI/AI ratio was an independent prognostic factor associated with patient survival. Histological determination of MI/AI ratio proved to be an economical and potentially useful adjunct in predicting clinical outcome of patients with cervical adenocarcinoma.

Adenocarcinoma↗

PubMed2006

Arginase induction by sodium phenylbutyrate in mouse tissues and human cell lines.

Hyperargininemia is a urea cycle disorder caused by mutations in the gene for arginase I (AI) resulting in elevated blood arginine and ammonia levels. Sodium phenylacetate and a precursor, sodium phenylbutyrate (NaPB) have been used to lower ammonia, conjugating glutamine to produce phenylacetylglutamine which is excreted in urine. The elevated arginine levels induce the second arginase (AII) in patient kidney and kidney tissue culture. It has been shown that NaPB increases expression of some target genes and we tested its effect on arginase induction. Eight 9-week old male mice fed on chow containing 7.5 g NaPB/kg rodent chow and drank water with 10 g NaPB/L, and four control mice had a normal diet. After one week all mice were sacrificed. The arginase specific activities for control and NaPB mice, respectively, were 38.2 and 59.4 U/mg in liver, 0.33 and 0.42 U/mg in kidney, and 0.29 and 1.19 U/mg in brain. Immunoprecipitation of arginase in each tissue with AI and AII antibodies showed the activity induced by NaPB is mostly AI. AII may also be induced in kidney. AI accounts for the fourfold increased activity in brain. In some cell lines, NaPB increased arginase activity up to fivefold depending on dose (1-5 mM) and exposure time (2-5 days); control and NaPB activities, respectively, are: erythroleukemia, HEL, 0.06 and 0.31 U/mg, and K562, 0.46 and 1.74 U/mg; embryonic kidney, HEK293, 1.98 and 3.58 U/mg; breast adenocarcinoma, MDA-MB-468, 1.11 and 4.06 U/mg; and prostate adenocarcinoma, PC-3, 0.55 and 3.20 U/mg. In MDA-MB-468 and HEK most, but not all, of the induced activity is AI. These studies suggest that NaPB may induce AI when used to treat urea cycle disorders. It is relatively less useful in AI deficiency, although it could have some effect in those patients with missense mutations.

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