50 resultados para SALIVARY-GLANDS


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Background: Thirst and dry mouth are common among hemodialysis (HD) patients. This paper reports a study to evaluate the impact of an acupressure program on HD patients’ thirst and salivary flow rates. Methods: The acupressure program included placebo, followed by true acupressure each applied for 4 weeks. Twenty-eight patients (mean age 57.6, SD = 16.13 years) first received a sticker as placebo acupressure at two acupoints CV23 and TE17 three times a week for 4 weeks, and then received true acupressure in the same area for the next 4 weeks. Salivary flow rate and thirst intensity were measured at baseline, during and after treatment completion for both the placebo and true acupressure program. Results: The true acupressure program was associated with significantly increased salivary flow rate (0.09 ± 0.08 ml/min at baseline to 0.12 ± 0.08 ml/min after treatments completion, p = 0.04). The mean thirst intensity also improved from 4.21 ± 2.66 at baseline to 2.43 ± 2.32 (p = 0.008) after treatment completion in HD patients. There was no statistically significant difference in pre-post program salivary flow rate; however, significant improvement in thirst intensity scores was observed (p = 0.009) in the placebo acupressure program. Conclusion: This study provides preliminary evidence that acupressure may be effective in improving salivary flow rates and thirst intensity.

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Intrinsically photosensitive retinal ganglion cells (ipRGC) signal environmental light level to the central circadian clock and contribute to the pupil light reflex. It is unknown if ipRGC activity is subject to extrinsic (central) or intrinsic (retinal) network-mediated circadian modulation during light entrainment and phase shifting. Eleven younger persons (18–30 years) with no ophthalmological, medical or sleep disorders participated. The activity of the inner (ipRGC) and outer retina (cone photoreceptors) was assessed hourly using the pupil light reflex during a 24 h period of constant environmental illumination (10 lux). Exogenous circadian cues of activity, sleep, posture, caffeine, ambient temperature, caloric intake and ambient illumination were controlled. Dim-light melatonin onset (DLMO) was determined from salivary melatonin assay at hourly intervals, and participant melatonin onset values were set to 14 h to adjust clock time to circadian time. Here we demonstrate in humans that the ipRGC controlled post-illumination pupil response has a circadian rhythm independent of external light cues. This circadian variation precedes melatonin onset and the minimum ipRGC driven pupil response occurs post melatonin onset. Outer retinal photoreceptor contributions to the inner retinal ipRGC driven post-illumination pupil response also show circadian variation whereas direct outer retinal cone inputs to the pupil light reflex do not, indicating that intrinsically photosensitive (melanopsin) retinal ganglion cells mediate this circadian variation.

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A system is described for calculating volume from a sequence of multiplanar 2D ultrasound images. Ultrasound images are captured using a video digitising card (Hauppauge Win/TV card) installed in a personal computer, and regions of interest transformed into 3D space using position and orientation data obtained from an electromagnetic device (Polbemus, Fastrak). The accuracy of the system was assessed by scanning 10 water filled balloons (13-141 ml), 10 kidneys (147  200 ml) and 16 fetal livers (8  37 ml) in water using an Acuson 128XP/10 (5 MHz curvilinear probe). Volume was calculated using the ellipsoid, planimetry, tetrahedral and ray tracing methods and compared with the actual volume measured by weighing (balloons) and water displacement (kidneys and livers). The mean percentage error for the ray tracing method was 0.9 ± 2.4%, 2.7 ± 2.3%, 6.6 ± 5.4% for balloons, kidneys and livers, respectively. So far the system has been used clinically to scan fetal livers and lungs, neonate brain ventricles and adult prostate glands.

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This PhD study has examined the population genetics of the Russian wheat aphid (RWA, Diuraphis noxia), one of the world’s most invasive agricultural pests, throughout its native and introduced global range. Firstly, this study investigated the geographic distribution of genetic diversity within and among RWA populations in western China. Analysis of mitochondrial data from 18 sites provided evidence for the long-term existence and expansion of RWAs in western China. The results refute the hypothesis that RWA is an exotic species only present in China since 1975. The estimated date of RWA expansion throughout western China coincides with the debut of wheat domestication and cultivation practices in western Asia in the Holocene. It is concluded that western China represents the limit of the far eastern native range of this species. Analysis of microsatellite data indicated high contemporary gene flow among northern populations in western China, while clear geographic isolation between northern and southern populations was identified across the Tianshan mountain range and extensive desert regions. Secondly, this study analyzed the worldwide pathway of invasion using both microsatellite and endosymbiont genetic data. Individual RWAs were obtained from native populations in Central Asia and the Middle East and invasive populations in Africa and the Americas. Results indicated two pathways of RWA invasion from 1) Syria in the Middle East to North Africa and 2) Turkey to South Africa, Mexico and then North and South America. Very little clone diversity was identified among invasive populations suggesting that a limited founder event occurred together with predominantly asexual reproduction and rapid population expansion. The most likely explanation for the rapid spread (within two years) from South Africa to the New World is by human movement, probably as a result of the transfer of wheat breeding material. Furthermore, the mitochondrial data revealed the presence of a universal haplotype and it is proposed that this haplotype is representative of a wheat associated super-clone that has gained dominance worldwide as a result of the widespread planting of domesticated wheat. Finally, this study examined salivary gland gene diversity to determine whether a functional basis for RWA invasiveness could be identified. Peroxidase DNA sequence data were obtained for a selection of worldwide RWA samples. Results demonstrated that most native populations were polymorphic while invasive populations were monomorphic, supporting previous conclusions relating to demographic founder effects in invasive populations. Purifying selection most likely explains the existence of a universal allele present in Middle Eastern populations, while balancing selection was evident in East Asian populations. Selection acting on the peroxidase gene may provide an allele-dependent advantage linked to the successful establishment of RWAs on wheat, and ultimately their invasion potential. In conclusion, this study is the most comprehensive molecular genetic investigation of RWA population genetics undertaken to date and provides significant insights into the source and pathway of global invasion and the potential existence of a wheat-adapted genotype that has colonised major wheat growing countries worldwide except for Australia. This research has major biosecurity implications for Australia’s grain industry.

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Objective: Theaflavin (TF) from the black tea can react to human salivary proline-rich proteins (PRPs) to form stains on exposed dental surfaces. Here, we employed a model of protein/pigment film using TF and dephosphorylated bovine b-casein (Db-CN), which has an extended conformation, similar to that of salivary PRPs, on a sensor surface to assess the efficacy of cysteine proteases (CPs) including papain, stem bromelain, and ficin, on removing TF bound to Db-CN and the control TF readsorption on the residual substrate surfaces was also measured. Methods: The protein/pigment complex film was built by using a quartz crystal microbalance with dissipation (QCM-D). The efficacies of CPs were assessed by Boltzman equation model. The surface details were detected by grazing angle infrared spectroscopy spectra, atomic force microscopy images, and contact angles. Results: The efficacy order of CPs on hydrolyzing protein/pigment complex film is ficin > papain > bromelain. The results from grazing angle infrared spectroscopy spectra, atomic force microscopy images, and contact angles demonstrated that TF bound on the Db- CN was effectively removed by the CPs, and the amount of TF readsorption on both the residual film of the Db-CN/TF and the Db-CN was markedly decreased after hydrolysis. Conclusion: This study indicates the potential application of the CPs for tooth stain removal and suggests that these enzymes are worthy of further investigation for use in oral healthcare.

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Charcot-Marie-Tooth neuropathy type 1 (CMT1) is an autosomal dominant disorder of peripheral nerve. The gene for CMT1 was originally localized to chromosome 1 by linkage to the Duffy blood group, but it has since been shown that not all CMT1 pedigrees show this linkage. We report here the results of linkage studies using five chromosome 1 markers - Duffy (Fy), antithrombin III (AT3), renin (REN), β-nerve growth factor (NGFB), and salivary amylase (AMY1) - in 16 CMT1 pedigrees. The total lod scores exclude close linkage of CMT1 to any of these markers. However, individual families show probable linkage of CMT1 to Duffy, AT3, and/or AMY1. No linkage was indicated with REN or NGFB. These results indicate that possible location of a CMT1 gene between the AMY1 and AT3 loci at p21 and q23, respectively, on chromosome 1 and support the theory that there is at least one other CMT1 gene.

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Introduction Patients with virally mediated head and neck cancer (VMHNC) often present with advanced nodal disease that is highly radioresponsive as demonstrated by tumour and nodal regression during treatment. The resultant changes may impact on the planned dose distribution and so adversely affect the therapeutic ratio. The aim of this study was to evaluate the dosimetric effect of treatment-induced anatomical changes in VMHNC patients who had undergone a re-plan. Methods Thirteen patients with virally mediated oropharyngeal or nasopharyngeal cancer who presented for definitive radiotherapy between 2005 and 2010 and who had a re-plan generated were investigated. The dosimetric effect of anatomical changes, was quantified by comparing dose volume histograms (DVH) of primary and nodal gross target volumes and organs at risk (OAR), including spinal cord and parotid glands, from the original plan and a comparison plan. Results Eleven 3DCRT and 2 IMRT plans were evaluated. Dose to the spinal cord and brainstem increased by 4.1% and 2.6%, respectively. Mean dose to the parotid glands also increased by 3.5%. In contrast, the dose received by 98% of the primary and nodal gross tumour volumes decreased by 0.15% and 0.3%, respectively when comparing the initial treatment plan to the comparison plan. Conclusion In this study, treatment-induced anatomical changes had the greatest impact on OAR dose with negligible effect on the dose to nodal gross tumour volumes. In the era of intensity modulated radiotherapy (IMRT), accounting for treatment-induced anatomical changes is important as focus is placed on minimising the acute and long-term side effects of treatment.

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BACKGROUND: The relationships between pain, stress and anxiety, and their effect on burn wound re-epithelialization have not been well explored to-date. The aim of this study was to investigate the effect of the Ditto (a hand-held electronic medical device providing procedural preparation and distraction) intervention on re-epithelialization rates in acute pediatric burns. METHODS/DESIGN: From August 2011 to August 2012, children (4-12 years) with an acute burn presenting to the Royal Children's Hospital, Brisbane, Australia fulfilled the study requirements and were randomized to [1] Ditto intervention or [2] standard practice. Burn re-epithelialization, pain intensity, anxiety and stress measures were obtained at every dressing change until complete wound re-epithelialization. RESULTS: One hundred and seventeen children were randomized and 75 children were analyzed (n=40 standard group; n=35 Ditto group). Inability to predict wound management resulted in 42 participants no longer meeting the eligibility criteria. Wounds in the Ditto intervention group re-epithelialized faster than the standard practice group (-2.14 days (CI: -4.38 to 0.10), p-value=0.061), and significantly faster when analyses were adjusted for mean burn depth (-2.26 days (CI: -4.48 to -0.04), p-value=0.046). Following procedural preparation at the first change of dressing, the Ditto group reported lower pain intensity scores (-0.64 (CI: -1.28, 0.01) p=0.052) and lower anxiety ratings (-1.79 (CI: -3.59, 0.01) p=0.051). At the second and third dressing removals average pain (FPS-R and FLACC) and anxiety scores (VAS-A) were at least one point lower when Ditto intervention was received. CONCLUSIONS: The Ditto procedural preparation and distraction device is a useful tool alongside pharmacological intervention to improve the rate of burn re-epithelialization and manage pain and anxiety during burn wound care procedures.

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BACKGROUND Burns and their associated wound care procedures evoke significant stress and anxiety, particularly for children. Little is known about the body's physiological stress reactions throughout the stages of re-epithelialization following an acute burn injury. Previously, serum and urinary cortisol have been used to measure stress in burn patients, however these measures are not suitable for a pediatric burn outpatient setting. AIM To assess the sensitivity of salivary cortisol and sAA in detecting stress during acute burn wound care procedures and to investigate the body's physiological stress reactions throughout burn re-epithelialization. METHODS Seventy-seven participants aged four to thirteen years who presented with an acute burn injury to the burn center at the Royal Children's Hospital, Brisbane, Australia, were recruited between August 2011 and August 2012. RESULTS Both biomarkers were responsive to the stress of burn wound care procedures. sAA levels were on average 50.2U/ml higher (p<0.001) at 10min post-dressing removal compared to baseline levels. Salivary cortisol levels showed a blunted effect with average levels at ten minutes post dressing removal decreasing by 0.54nmol/L (p<0.001) compared to baseline levels. sAA levels were associated with pain (p=0.021), no medication (p=0.047) and Child Trauma Screening Questionnaire scores at three months post re-epithelialization (p=0.008). Similarly, salivary cortisol was associated with no medication (p<0.001), pain scores (p=0.045) and total body surface area of the burn (p=0.010). CONCLUSION Factors which support the use of sAA over salivary cortisol to assess stress during morning acute burn wound care procedures include; sensitivity, morning clinic times relative to cortisol's diurnal peaks, and relative cost.

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Ghrelin is a 28-amino acid peptide hormone produced predominantly in the stomach but also in a range of normal cell types and tumors, where it has endocrine, paracrine, and autocrine roles. Previously, we have demonstrated that ghrelin has proliferative and antiapoptotic effects in endometrial cancer cell lines, suggesting a potential role in promoting tumor growth. In the present study, we investigated the effect of ghrelin receptor, GHSR, and gene silencing in vitro and in vivo and characterized ghrelin and GHSR1a protein expression in human endometrial tumors. GHSR gene silencing was achieved in the Ishikawa and KLE endometrial cancer cell lines, using a lentiviral short-hairpin RNA targeting GHSR. The effects of GHSR1a knockdown were further analyzed in vivo using the Ishikawa cell line in a NOD/SCID xenograft model. Cell proliferation was reduced in cultured GHSR1a knockdown Ishikawa and KLE cells compared with scrambled controls in the absence of exogenously applied ghrelin and in response to exogenous ghrelin (1,000 nM). The tumor volumes were reduced significantly in GHSR1a knockdown Ishikawa mouse xenograft tumors compared with scrambled control tumours. Using immunohistochemistry, we demonstrated that ghrelin and GHSR1a are expressed in benign and cancerous glands in human endometrial tissue specimens, although there was no correlation between the intensity of staining and cancer grade. These data indicate that downregulation of GHSR expression significantly inhibits endometrial cancer cell line and mouse xenograft tumour growth. This is the first preclinical evidence that downregulation of GHSR may be therapeutic in endometrial cancer.

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Mammographic density (MD) is the area of breast tissue that appears radiologically white on mammography. Although high MD is a strong risk factor for breast cancer, independent of BRCA1/2 mutation status, the molecular basis of high MD and its associated breast cancer risk is poorly understood. MD studies will benefit from an animal model, where hormonal, gene and drug perturbations on MD can be measured in a preclinical context. High and low MD tissues were selectively sampled by stereotactic biopsy from operative specimens of high-risk women undergoing prophylactic mastectomy. The high and low MD tissues were transferred into separate vascularised biochambers in the groins of SCID mice. Chamber material was harvested after 6 weeks for histological analyses and immunohistochemistry for cytokeratins, vimentin and a human-specific mitochondrial antigen. Within-individual analysis was performed in replicate mice, eliminating confounding by age, body mass index and process-related factors, and comparisons were made to the parental human tissue. Maintenance of differential MD post-propagation was assessed radiographically. Immunohistochemical staining confirmed the preservation of human glandular and stromal components in the murine biochambers, with maintenance of radiographic MD differential. Propagated high MD regions had higher stromal (p = 0.0002) and lower adipose (p = 0.0006) composition, reflecting the findings in the original human breast tissue, although glands appeared small and non-complex in both high and low MD groups. No significant differences were observed in glandular area (p = 0.4) or count (p = 0.4) between high and low MD biochamber tissues. Human mammary glandular and stromal tissues were viably maintained in murine biochambers, with preservation of differential radiographic density and histological features. Our study provides a murine model for future studies into the biomolecular basis of MD as a risk factor for breast cancer.

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Fibroblast growth factors (FGFs) are potent mitogens, morphogens, and inducers of angiogenesis, and FGF signaling governs the genesis of diverse tissues and organs from the earliest stages. With such fundamental embryonic and homeostatic roles, it follows that aberrant FGF signaling underlies a variety of diseases. Pathological modifications to FGF expression are known to cause salivary gland aplasia and autosomal dominant hypophosphatemic rickets, while mutations in FGF receptors (FGFRs) result in a range of skeletal dysplasias. Anomalous FGF signaling is also associated with cancer development and progression. Examples include the overexpression of FGF2 and FGF6 in prostate cancer, and FGF8 overexpression in breast and prostate cancers. Alterations in FGF signaling regulators also impact tumorigenesis, which is exemplified by the down-regulation of Sprouty 1, a negative regulator of FGF signaling, in prostate cancer. In addition, several FGFRs are mutated in human cancers (including FGFR2 in gastric cancer and FGFR3 in bladder cancer). We recently identified intriguing alterations in the FGF pathway in a novel model of bladder carcinoma that consists of a parental cell line (TSU-Pr1/T24) and two sublines with increasing metastatic potential (TSU-Pr1-B1 and TSU-Pr1-B2), which were derived successively through in vivo cycling. It was found that the increasingly metastatic sublines (TSU-Pr1-B1 and TSU-Pr1-B2) had undergone a mesenchymal to epithelial transition. FGFR2IIIc expression, which is normally expressed in mesenchymal cells, was increased in the epithelial-like TSU-Pr1-B1 and TSU-Pr1-B2 sublines and FGFR2 knock-down was associated with the reversion of cells from an epithelial to a mesenchymal phenotype. These observations suggest that modified FGF pathway signaling should be considered when studying other cancer types.

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Carcinoma ex pleomorphic adenoma (Ca ex PA) is a carcinoma arising from a primary or recurrent benign pleomorphic adenoma. It often poses a diagnostic challenge to clinicians and pathologists. This study intends to review the literature and highlight the current clinical and molecular perspectives about this entity. The most common clinical presentation of CA ex PA is of a firm mass in the parotid gland. The proportion of adenoma and carcinoma components determines the macroscopic features of this neoplasm. The entity is difficult to diagnose pre-operatively. Pathologic assessment is the gold standard for making the diagnosis. Treatment for Ca ex PA often involves an ablative surgical procedure which may be followed by radiotherapy. Overall, patients with Ca ex PA have a poor prognosis. Accurate diagnosis and aggressive surgical management of patients presenting with Ca ex PA can increase their survival rates. Molecular studies have revealed that the development of Ca ex PA follows a multi-step model of carcinogenesis, with the progressive loss of heterozygosity at chromosomal arms 8q, then 12q and finally 17p. There are specific candidate genes in these regions that are associated with particular stages in the progression of Ca ex PA. In addition, many genes which regulate tumour suppression, cell cycle control, growth factors and cell-cell adhesion play a role in the development and progression of Ca ex PA. It is hopeful that these molecular data can give clues for the diagnosis and management of the disease.

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Technical dinitrotoluene (DNT) is a mixture of 2,4- and 2,6-DNT. In humans, industrial or environmental exposure can occur orally, by inhalation, or by skin contact. The classification of DNT as an 'animal carcinogen' is based on the formation of malignant tumors in kidneys, liver, and mammary glands of rats and mice. Clear signs of toxic nephropathy were found in rats dosed with DNT, and the concept was derived of an interrelation between renal toxicity and carcinogenicity. Recent data point to the carcinogenicity of DNT on the urinary tract of exposed humans. Between 1984 and 1997, 6 cases of urothelial cancer and 14 cases of renal cell cancer were diagnosed in a group of 500 underground mining workers in the copper mining industry of the former GDR and having high exposures to explosives containing technical DNT. The incidences of both urothelial and renal cell tumors in this group were 4.5 and 14.3 times higher, respectively, than anticipated on the basis of the cancer registers of the GDR. The genotyping of all identified tumor patients for the polymorphic enzymes NAT2, GSTM1, and GSTT1 identified the urothelial tumor cases as exclusively 'slow acetylates'. A group of 161 miners highly exposed to DNT was investigated for signs of subclinical renal damage. The exposures were categorized semi-quantitatively into 'low', 'medium', 'high', and 'very high'. A straight dose-dependence of the excretion of urinary biomarker proteins with the ranking of exposure was seen. Biomarker excretion (alpha1-microglobulin, glutathione S-transferases alpha and pi) indicated that DNT-induced damage was directed toward the tubular system. New data on DNT-exposed humans appear consistent with the concept of cancer initiation by DNT isomers and the subsequent promotion of renal carcinogenesis by selective damage to the proximal tubule. The differential pathways of metabolic activation of DNT appear to apply to the proximal tubule of the kidney and to the urothelium of the renal pelvis and lower urinary tract as target tissues of carcinogenicity.

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Hypothesis Melatonin synthesis, which is directly controlled by the central circadian pacemaker indicates the circadian phase better than rectal temperature. Methods: Thirty four men (16-32 years, 7 morning, 13 neither, 14 evening types) performed a constant routine (24-26-hr bedrest, < 30 lux, 18-20°C, hourly isocaloric diet). Salivary melatonin level was determined hourly and rectal temperature was continuously recorded. Results: The nadir of rectal temperature occurred 1.5 hr (P = 0.017), the onset of melatonin synthesis 3 hr earlier (P < 0.0001) in morning than in evening types. Morningness was not related to the quantitative but significantly to the temporal parameters, closer to those of melatonin than of rectal temperature. Conclusions: The melatonin onset is a more reliable indicator of the diurnal type than the nadir of rectal temperature. As morningness has been associated with intolerance to shiftwork, melatonin profiling provides a suitable basis for the establishment of directed preventive measures.