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The growth hormone receptor (GHR) 1A mRNA decreases after calving in the liver of Holstein dairy cows and may coordinate nutrient partitioning. The hypothesis that the decrease in GHR1A mRNA around the time of calving was characteristic of a second dairy breed was tested by examining Guernsey cows in addition to Holstein cows. Holstein and Guernsey cows were housed together and paired by parity and expected calving date. Liver biopsies and blood samples were collected prepartum (d -20 ± 1) and postpartum on d 3, and d 14 ± 1. The amounts of GHR1A, GHR1B, GHR1C, and insulin-like growth factor (IGF)1 mRNA were determined by quantitative reverse transcription polymerase chain reaction. Blood concentrations of growth hormone (GH) and IGF1 were measured by RIA. Both breeds underwent a decrease in GHR1A mRNA, a decrease in liver IGF1 mRNA, a decrease in blood IGF1, and an increase in blood GH after calving. The decrease in liver GHR1A and IGF1 mRNA after calving may be an inherent characteristic of dairy breeds that enables nutrient partitioning for greater milk production. Independent genetic selection in 2 dairy breeds seemingly exploited a similar mechanism, reduced GHR1A expression, to decrease blood IGF1 and increase blood GH, a key hormone involved in nutrient partitioning. [ABSTRACT FROM AUTHOR]

STATEMENT OF PROBLEM: Dentists and patients are regularly confronted by a difficult treatment question: should a tooth be saved through root canal treatment and restoration (RCT), be extracted without any tooth replacement, be replaced with a fixed partial denture (FPD) or an implant-supported single crown (ISC)? PURPOSE: The purpose of this systematic review was to compare the outcomes, benefits, and harms of endodontic care and restoration compared to extraction and placement of ISCs, FPDs, or extraction without tooth replacement. MATERIAL AND METHODS: Searches performed in MEDLINE, Cochrane, and EMBASE databases were enriched by hand searches, citation mining, and expert recommendation. Evidence tables were developed following quality and inclusion criteria assessment. Pooled and weighted mean success and survival rates, with associated confidence intervals, were calculated for single implant crowns, fixed partial dentures, and initial nonsurgical root canal treatments. Data related to extraction without tooth replacement and psychosocial outcomes were evaluated by a narrative review due to literature limitations. RESULTS: The 143 selected studies varied considerably in design, success definition, assessment methods, operator type, and sample size. Direct comparison of treatment types was extremely rare. Limited psychosocial data revealed the traumatic effect of loss of visible teeth. Economic data were largely absent. Success rates for ISCs were higher than for RCTs and FPDs, respectively; however, success criteria differed greatly among treatment types, rendering direct comparison of success rates futile. Long-term survival rates for ISCs and RCTs were similar and superior to those for FPDs. CONCLUSIONS: Lack of comparative studies with similar outcomes criteria with comparable time intervals limited comparison of these treatments. ISC and RCT treatments resulted in superior long-term survival, compared to FPDs. Limited data suggested that extraction without replacement resulted in inferior psychosocial outcomes compared to alternatives. Long-term, prospective clinical trials with large sample sizes and clearly defined outcomes criteria are needed. [ABSTRACT FROM AUTHOR]

SubjectsSubjects were 176 physically disabled school students (ages 10 to 27) who received baseline caries examinations and were assigned nonrandomly to either the xylitol candy group (n = 126) or the control group (n = 50). After 18 months, 145 received follow-up examinations (xylitol n = 105, control n = 40).TreatmentSubjects in the xylitol group sucked a xylitol candy (49% xylitol, but weight not stated) 3 times each school day, but not on weekends or school vacations. Compliance was reported to be good, with only occasional refusals to use the candy. Control group subjects did nothing.Main Outcome MeasureThe main outcome measure was the 18-month increment in decayed, missing, and filled permanent teeth (DMFS), determined by subtracting the baseline DMFS score from the final, 18-month DMFS score. Examinations were performed by 2 calibrated examiners using World Health Organization criteria for detecting caries into dentin.Main ResultThe mean increment in the xylitol group was -1.2 +/- 3.4, compared with 3.5 +/- 4.6 in the control group. The negative increment in the xylitol group was due to 212 surfaces (1.6%) among xylitol subjects being scored as decayed at baseline and sound at 18 months, compared to 1 such surface (0.0%) among control subjects. In contrast, 41 surfaces (0.3%) scored sound at baseline were scored as decayed, filled, or missing at 18 months in the xylitol group, compared with 192 surfaces (3.8%) in the control group.ConclusionsXylitol candies had both a remineralization effect and a preventive effect on coronal caries compared with no use of candies. [ABSTRACT FROM AUTHOR]

Presents a study which examined ovarian follicular responses to high, frequent doses of exogenous luteinizing hormone pulses at levels associated with follicular cysts in experiments in lactating dairy cows . Materials and methods used; Details of the experiments with normal estrous cycles and early postpartum cows; Discussion.

Greater blood concentrations of nonesterified fatty acids (NEFA) and lesser blood concentrations of glucose are indicative of the normal process of nutrient partitioning that occurs in early postpartum dairy cows. The objective was to determine the relationship between blood NEFA and glucose concentrations and subsequent conception at first insemination in postpartum dairy cows. Holstein (n = 148) and Guernsey (n = 8) dairy cows were blood sampled at approximately d 10, 7, and 3 prepartum, on the day of calving and 3, 7, 14, and 21 d postpartum for measurement of NEFA and glucose concentrations. Serum and plasma were harvested and used for measurement of NEFA and glucose concentrations, respectively. Cows were given a presynchronization treatment (2 injections of PGF2α 14 d apart) with the second PGF2α injection occurring 14 d before the initiation of the timed AI (TAI) protocol. Blood for determination of progesterone concentrations was collected at each presynchronization injection and at the initiation of the TAI protocol that was used for first insemination (74 ± 7 d postpartum). Cows were considered noncycling if serum progesterone concentrations at the 2 presynchronization PGF2α injections (d 37 and 51 ± 7 postpartum) and at the initiation of the TAI protocol (d 65 ± 7 postpartum) were =1 ng/mL, and there was no indication of ovulation or presence of a corpus luteum by ultrasound examination at the initiation of the TAI protocol. Pregnancy was determined at 33 d and again at 61 d after first insemination by using ultrasound. Across all days, serum NEFA and plasma glucose concentrations were not different between cows that ovulated before the initiation of the TAI program (cycling) compared with those that did not ovulate (noncycling). Serum NEFA concentrations, however, were less and plasma glucose concentrations were greater during the early postpartum period for cows that subsequently became pregnant at first insemination compared with those that failed to become pregnant. Logistic regressions were used to predict the probability of pregnancy based on NEFA and glucose concentrations from individual days. The prediction with the greatest likelihood ratio was for d 3 postpartum NEFA and glucose concentrations. Nutritional status during the early postpartum period (within 1 wk after calving), as indicated by blood NEFA and glucose concentrations, may affect subsequent fertility by a mechanism that is independent from interval to first ovulation. [ABSTRACT FROM AUTHOR]

Timed artificial insemination (TAI) protocols use PGF2α and GnRH injections to synchronize ovulation. The objective was to evaluate the PGPG protocol (d 0, PGF2α; d 3, GnRH; d 11, PGF2α; d 13, GnRH and TAI) for first TAI and also examine methods for second TAI in nonpregnant cows. A factorial test of the first PGF2α, and first GnRH injections within the PGPG protocol was performed (the last PGF2α and GnRH injections were deemed essential to the TAI). Lactating dairy cows (n = 804) in a commercial herd were assigned to 1 of 5 first-TAI treatments, which were PGPG, GPG (d 0, no treatment; d 3, GnRH; d 11, PGF2α; d 13, GnRH and TAI), PPG (d 0, PGF2α; d 3, no treatment; d 11, PGF2α; d 13, GnRH and TAI), and PG (d 0, no treatment; d 3, no treatment; d 11, PGF2α; d 13, GnRH and TAI); the Ovsynch protocol (GnRH, 7 d, PGF2α, 2 d, GnRH and TAI) was the positive control. For resynchronization, cows received either GnRH or the control (no injection) on d 22 after TAI. Nonpregnant cows on d 28 were then treated with PGF2α, on d 29, GnRH on d 31, and TAI [i.e., resynchronization treatments of ReGPG (received GnRH on d 22) and RePG (did not receive GnRH on d 22)]. Pregnancy rates for PGPG, GPG, PPG, PG, and Ovsynch were similar at d 28 after first TAI. Analyses of multiple explanatory factors by logistic regression detected an effect of uterine or ovarian abnormality on the d-28 pregnancy rate (normal more likely to be pregnant). Day-42 pregnancy rates were affected by uterine or ovarian abnormality (normal more likely to be pregnant), postpartum disease occurrence (healthy cows more likely to be pregnant), milk production, and days in milk. Treatment was not significant for the d-42 pregnancy rate. Effects of postpartum disease, milk production, and days in milk on the d-42 pregnancy rate were apparently manifested through their effects on embryonic loss between d 28 and 42 of pregnancy. High-producing cows that received TAI early postpartum were most likely to experience embryonic loss. Day-42 pregnancy rates after the resynchronization treatment were affected by an interaction of the first synchronization treatment with the resynchronization treatment. We concluded that although PGPG can be used for TAI, a simpler TAI protocol that includes the last 2 injections (PGF2α, 2 d; GnRH and TAI) would be equally effective. [ABSTRACT FROM AUTHOR]