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•Early childhood caries is a complex, multifactorial oral disease.•About half of U.S. children do not receive regular oral health care.•Parental depression and COVID-19 were associated with increased cancelations and failed dental appointments.•Canceled or no-show appointments were associated with increased reported alcohol use and low social support.•Pediatric routine dental appointments and pediatric study visits were observed over a 2-year period.

•Wind erosion is a major resource concern for rangeland managers because it can impact soil health, ecosystem structure and function, hydrologic processes, agricultural production, and air quality.•Despite its significance, little is known about which landscapes are eroding, by how much, and when.•The National Wind Erosion Research Network was established in 2014 to develop tools for monitoring and assessing wind erosion and dust emissions across the United States.•The Network, currently consisting of 13 sites, creates opportunities to enhance existing rangeland soil, vegetation, and air quality monitoring programs.•Decision-support tools developed by the Network will improve the prediction and management of wind erosion across rangeland ecosystems.

Recent evidence suggests that the ovine premammillary hypothalamic area (PMH) is an important target for the pineal hormone, melatonin, and its role in seasonal reproduction. In rodents, the PMH is a complex region consisting of several cell groups with differing neurochemical content and anatomical connections. Therefore, to obtain a better understanding of the potential neural targets for melatonin in this area of the sheep brain, we have undertaken a detailed anatomical characterization of the PMH, including its nuclear divisions and the location of neuropeptide/neurotransmitter cells within them. By combining immunocytochemistry for NeuN, a neuronal marker, with Nissl staining in anestrous, ovariectomized, estradiol-treated ewes, we identified three nuclei within the PMH: a caudal continuation of the hypothalamic arcuate nucleus (cARC), the ventral division of the premammillary nucleus (PMv), and the ventral tuberomammillary nucleus (TMv). The cARC contained neurons that were immunoreactive for tyrosine hydroxylase, dynorphin, estrogen receptor α, cocaine- and amphetamine-regulated transcript peptide (CART), and nitric oxide synthase (NOS). The PMv was also characterized by the presence of cells that contained NOS and CART, although the size of these cells was larger than that of their corresponding phenotype in the cARC. By contrast, in the TMv, of the markers examined in the present study, only fibers immunoreactive for orexin were seen. Thus, the ovine PMH is a heterogeneous region comprised of three subdivisions, each with distinct morphological and neurochemical characteristics. This anatomical map of the PMH provides a basis for future studies to determine the functional contribution of each component to the influence of melatonin on seasonal reproduction.

Allelic loss of the chromosome 19q arm is a frequent event in human diffuse gliomas, suggesting that it contains a tumor suppressor gene. Recent deletion mapping studies have broadly implicated a 1.6-Mb interval between D19S241E and D19S596, with a limited subset of tumors, suggesting that the region may be as narrow as 150 kb. Focusing on this smaller interval, we have used cDNA selection, exon amplification, and genomic sequencing to identify three novel transcripts (EHD2, GLTSCR1,and GLTSCR2) and to map two known genes (SEPW1and CRX). A partial transcript map of 19 transcripts and two EST markers has been constructed for the 1.6-Mb interval D19S241E–D19S596. Ten of these transcripts, including the 5 mapped to the 150-kb deletion interval, have been examined for alterations in a panel of gliomas with allelic loss of 19q. Tumor-specific alterations have not been identified in the transcripts examined thus far. Collectively, these data should facilitate subsequent efforts to identify and characterize the remaining transcripts in the 1.6-Mb interval.

Potentially cariogenic microorganisms cultured from noncarious and carious root and coronal (enamel) surfaces were quantitatively compared in patients 22 to 84 years of age (mean, 52 years). We collected 150 plaque specimens from 26 in situ teeth with initial root lesions and from 25 extracted teeth with advanced root lesions. The frequencies of isolation of Streptococcus mutans, Actinomyces viscosus, and Lactobacillus spp. were, respectively, 94, 72, and 51% at the noncarious root site; 98, 71, and 54% at the root lesion; 84, 61, and 44% at the noncarious enamel site; and 100, 66, and 90% at the enamel lesion. The streptococci made up the largest mean proportion of the total anaerobic cultivable microflora, ranging from 31.2% at the noncarious enamel site to 37.6% at the root lesion, while S. mutans varied between 18% at the noncarious enamel and root surfaces and approximately 24% at both the enamel and root lesions. The proportion of actinomyces ranged from 12.3% at the root lesion to 23.6% at the noncarious root site, while A. viscosus varied from 7.8% at the root lesion to 15.1% at the noncarious root site. The largest mean proportion of lactobacilli (4.2%) was recovered at the enamel lesion site. Proportions of Candida spp. made up less than 0.1% at all sites. Proportions of microorganisms did not differ significantly between noncarious enamel and root sites, but the noncarious coronal and root sites had higher (P less than 0.05) proportions of actinomyces than did the root lesion. Also, enamel lesions had a greater (P less than 0.05) percentage of Lactobacillus spp. than did root lesions. The number of streptococci recovered from the root lesion was greater (P less than 0.01) than the number of actinomyces at the same site. S. mutans was recovered from initial root lesions in greater numbers (P less than 0.001) than were actinomyces and lactobacilli. The number of S. mutans recovered at the initial root lesions was greater (P less than 0.01) than that recovered from the advanced root lesions.

Serum, gingival crevicular fluid, and parotid, submandibular, and labial minor gland saliva from four individuals stimulated glucan formation from sucrose by the Streptococcus mutans strain 6715 dextransucrase (EC 2.4.1.5). At final dilutions of 1:10 all of the fluids stimulated crude enzyme preparations approximately 1.8-fold. The fluids stimulated the purified water-insoluble glucan-synthesizing form of the dextransucrase approximately 3.2-fold and the water-soluble glucan-producing form of the enzyme approximately 2.4-fold. The fluids all contained concentrations of stimulatory material that could be reduced to undetectable levels only after dilutions of greater than 1:1,000. The increased rates of glucan formation caused by the fluids and dextran were additive, indicating that stimulation by the fluids was primarily due to interactions with entities other than glucan primer molecules. In contrast, the elevated levels of glucan formation in the presence of the fluids was not further enhanced by the addition of lysophosphatidylcholine. Lysophosphatidylcholine purified from parotid and submandibular saliva by solvent extraction and thin-layer chromatography stimulated the dextransucrase as effectively as egg yolk lysophosphatidylcholine. Thus, phospholipids normally found in human oral fluids can enhance the activity of an enzyme believed to be directly associated with the cariogenic potential of S. mutans.

In sheep, females have twice as many neurokinin B (NKB)-containing neurons in the arcuate nucleus as males, and nearly all of these neurons contain estrogen receptor-α. Further, we have preliminary data [McManus et al., Society for Neuroscience Abstr. 760.8, 2005] that i.c.v. administration of an agonist for the NKB receptor, neurokinin-3 receptor (NK3R), induces a dramatic increase in LH concentrations in follicular phase ewes, indicating that NKB may mediate the estradiol (E2)-induced preovulatory LH surge. We have identified NK3R in the retrochiasmatic area (RCh), and in this study, tested the hypothesis that administration of the NK3R agonist, senktide, in the RCh would induce surge-like concentrations of LH in early follicular phase ewes (i.e., prior to normal onset of the surge). Ovary-intact, breeding season ewes (n=5), with bilateral guide cannulae surgically implanted aiming at the RCh, were estrous-synchronized using a combination of PGF2α injections and intravaginal progesterone-releasing devices (P4). Beginning 24 h following P4 removal (i.e., early follicular phase), jugular blood samples were collected every 12 min from 36 min before to 4 hrs after insertion of microimplants either containing crystalline senktide or left empty (control). The frequency of blood collection was increased to every 4 min from hour 1 to hour 2 after the beginning of treatment to determine if senktide-induced increases in LH concentrations were due to high-frequency LH pulses. Implants were removed after 4 h, and blood continued to be collected hourly for an additional 4 h. This protocol was repeated the next follicular phase using a cross-over design. LH concentrations were determined by RIA and area under the curve (AUC) of LH compared between senktide and control treatments in the first 4 h and last 4 h following treatment by two-way repeated measures ANOVA. In 4 of 5 ewes receiving senktide, there was a sustained increase in LH concentrations beginning about 2 hrs after and peaking (LH concentrations 25-35 ng/ml) 5-6 hrs after the start of treatment. There was no obvious change in LH with control treatment in these ewes, so there was a significant treatment x time interaction (p<0.05). In the last 4 h of blood collection, LH AUC was significantly greater in senktide-treated compared with control-treated ewes (4920 ± 1192 vs 861 ± 275 ng/ml*min; p <0.05). Only 2 of 5 ewes had clear LH pulses during the period of 4-min sampling that began 1 h after insertion of senktide microimplants, suggesting that the NK3R agonist may be inducing an LH surge. Because NK3R agonist in the RCh appeared to advance the onset of the LH surge in early follicular phase ewes, we hypothesize that in ewes, the RCh is a site of action of neurokinin B for GnRH and LH surge generation. Support provided by NIH HD17864 (R.L.G.).

There is now considerable evidence that a neural circuit involving A15 dopaminergic (DA) neurons plays a key role in the seasonal changes in response to estradiol (E) negative feedback in the ewe. Previous studies using local E microimplants and tract tracing have identified E-responsive neurons in the preoptic (POA) and retrochiasmatic areas (RCh) that act via A15 DA neurons to inhibit LH pulse frequency during anestrus, but not in the breeding season. We have recently reported that E microimplants in the arcuate nucleus (ARC) also reduce LH pulse frequency in anestrous, but not breeding season, ewes. In this experiment, we tested the hypothesis that these E-responsive neurons in the ARC also act via DA neurons. Our experimental design was based on prior studies in which i.m. injection of the dopamine D2-receptor antagonist, sulpiride, reversed the inhibition of LH pulse frequency by E microimplants in the POA or in the RCh of anestrous ewes. Anestrous, ovariectomized ewes (n=10) were anesthetized and surgically implanted with bilateral guide cannulae into the ARC. After full recovery, blood was collected by jugular venipuncture from the ewes at 12 min intervals for three 4-h periods. The first collection was a pre-treatment control (No E). The second collection (E ARC) was on day 5 after insertion of bilateral E microimplants (22-ga tubing with crystalline E tamped into the lumen). Immediately following the E ARC collection, ewes were injected with sulpiride, i.m. (1.2 mg/kg in 0.1M tartaric acid), and blood collected for the final 4 h period (EARC+S). Plasma LH concentrations were determined via radioimmunoassay. The number of LH pulses in 4 h was compared across treatments using the Friedman test. When significant differences were detected, pairwise comparisons were made between treatments using the Wilcoxon signed rank test. One ewe was excluded from further analysis when no LH pulses were detected in the No E control period and a pituitary tumor compressing the ARC was found on post-mortem exam. Consistent with our previous findings, LH pulse frequency was significantly reduced (p<0.05) by E microimplants into the ARC (No E: 3.33 ± 0.17 pulses/4 h ; E ARC: 1.78 ± 0.49 pulses/4 h). Contrary to our hypothesis, LH pulse frequency remained significantly suppressed (p<0.05) following sulpiride treatment (EARC+S: 1.67 ± 0.33 pulse/4 h) compared with the No E controls. LH pulse frequency for EARC+S was not significantly different from the pulse frequency detected following E treatment alone (p=0.813). These results indicate that E acts in the ARC of anestrous ewes via a novel pathway independent of the dopaminergic pathway through which E-responsive neurons in the POA and RCh act to suppress LH pulse frequency. This is most consistent with the hypothesis that seasonal reproduction involves redundant inhibition of GnRH and LH pulse frequency through both A15 DA and ARC neurons. (Funding provided by HD17864)(platform)

Estradiol (E2), acting through estrogen receptor-α (ERα), suppresses GnRH and LH pulse frequency in anestrous, but not breeding season, ewes. However, GnRH neurons do not contain ERα. There is ERα in the arcuate nucleus (ARC), but the negative feedback effects of E2 in the ARC have not been tested. This study tested the hypothesis that E2 acts in the ARC to suppress LH pulse frequency in anestrous ewes, and examined the possible role of steroid receptor coactivator-1 (SRC-1), which enhances ERα transcriptional activity, by determining the effects of E2 treatment on SRC-1-ir. In experiment 1, ovariectomized (OVX) ewes were treated with E2-filled or blank microimplants in ARC, or s.c. E2 implants, in randomized order with one week between treatments during either anestrous (n=5) or breeding season (n=6). Blood was collected every 12 min for 6 h on day 5 of treatment and plasma LH measured by RIA. At the end of the experiment, ewes were treated with either blank or E2-filled microimplants in the ARC (n=2/group/season), or s.c. E2 implants (n=1 anestrus; n=2 breeding season) for another 5 days, then euthanized, heads perfused, and hypothalami collected. Coronal sections (50 μm) through the ARC of anestrous ewes were processed for dual immunofluorescent detection of ERα and SRC-1, and percentage colocalization determined using confocal microscopy. In experiment 2, OVX, anestrous ewes with and without s.c. E2 implants (n=4/group) were similarly perfused and 50 μm sections through the caudal ARC processed and analyzed for ERα and SRC-1 immunofluorescence as in Exp. 1. In Exp 1, E2 implants significantly reduced LH pulse frequency (ARC: 0.6 ± 0.4 pulse/6h; s.c.: 0.2 ± 0.2 pulse/6h) compared with blank controls (4.2 ± 0.7 pulse/6h) in anestrous ewes (P<0.05), but not in breeding season ewes. ARC E2 also reduced the percentage of ERα neurons containing SRC-1-ir in anestrous ewes (E2 vs blank: 58.7% vs 90.7%) in Exp 1, as did s.c E2 treatment in Exp. 2 (OVX+E: 57.8 ± 2.3%; OVX: 90.1 ± 2.9%). The simplest explanation for these results is that structural changes caused by SRC-1 interactions with the E2-ERα transcriptional complex prevent immunological detection of this co-factor. We thus propose that ERα neurons in the ARC mediate seasonal suppression of LH pulse frequency in ewes, and SRC-1 may be a component of the cellular mechanism mediating increased responsiveness to E2 negative feedback in anestrus. Supported by NIH Grant 5P20RR016477 to the West Virginia IDeA Network for Biomedical Research Excellence, NSF 0620195 (H.J.B.), and NIH HD17864 (R.L.G.).

A human oculogenital strain of Chlamydia trachomatis was instilled intravaginally in the outbred CF-1 mouse to establish cervical infection. The mice were neither hormonally nor immunologically manipulated before inoculation. Duration of chlamydial excretion varied from two to ten days. In the culture-positive animals, IgG and IgM antibody titers were elevated in 38% and 17%, respectively. Neither intracytoplasmic inclusions nor elementary bodies of C. trachomatis were detected in genital tissues. Infection was limited primarily to the cervix and only rarely extended into the uterus. Chlamydial infection could only be established during specific periods of the estrus cycle (metestrus-2, diestrus, and proestrus; P < .001), stages when leukocytes are present in the vaginal smear. Thus, chlamydial infection of the cervix is cycle-dependent in the mouse. In summary, infection of the cervix of the mouse has been established with a human oculogenital strain of C. trachomatis and may be useful as a model of human chlamydial cervicitis.