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21.

Objective

The aim of this study is to assess whether C1772T and G1790A hypoxia-inducible factor-1 (HIF-1)α polymorphisms are associated with risk of oral lichen planus (OLP).

Material and methods

Restriction fragment length polymorphism analysis was used to investigate HIF-1α C1779T and G1790A polymorphisms in 32 OLP and 88 individuals without OLP.

Results

The frequency of the CC, TT, GA, and AA genotypes was higher in patients with OLP. Notably, individuals carrying the C and A, and T and A haplotypes showed a significant association OLP risk.

Conclusions

Our study demonstrated that the C1772T and G1790A polymorphisms of HIF-1α gene increased the risk of OLP. C1772T and G1790A polymorphisms of HIF-1α gene had differing patterns of allelic imbalance in the normal samples and subsequent chronic lesions. Further studies are necessary to elucidate the HIF-1α pathway in OLP, which would facilitate the development of novel therapeutic strategies for the prevention and treatment of OLP.

Clinical relevance

These results, in conjunction with previous studies, suggest that HIF-1α may play important roles in the chronicity of oral mucosa lesions of OLP patients. Taken together, we suggest that HIF-1α polymorphisms enhance its target genes, thereby altering the microenvironment and supporting sequential release of inflammatory mediators or cellular events in OLP. It appears unlikely that inhibition of a single proinflammatory mediator will prove useful in clinical practice, but several ways to reprogram mediators engaged in a wide array of roles simultaneously are encouraging.  相似文献   
22.

Objective

This study aimed to investigate the expression of the MSH2 DNA repair protein in head and neck squamous cell carcinoma (HNSCC) in order to analyze its association with clinicopathologic factors and overall survival of patients.

Material and Methods

Clinical data and primary lesions of HNSSC were collected from 55 patients who underwent surgical resection with postoperative radiotherapy in Montes Claros, state of Minas Gerais, Brazil, between 2000 and 2008. Immunohistochemical reactions were performed to analyze MSH2 protein expression.

Results

Bivariate analysis showed no significant correlation or association between MSH2 expression and clinicopathologic parameters by Mann-Whitney and Kruskal-Wallis tests. Patients with locoregional metastatic disease (OR=4.949, p<0.001) and lower MSH2 immunohistochemical expressions (OR=2.943, p=0.032) presented poorer survival for HNSCC by Cox regression models.

Conclusions

Our data demonstrated that lower MSH2 expression might contribute to a higher clinic aggressiveness of HNSCC by promoting an unfavorable outcome.  相似文献   
23.
The aim of this study was to investigate the effects of aging on the central nervous system steroid and myelin basic protein (MBP) profiles. Forty-seven male Sprague-Dawley rats (newborn, 1, 6, 12 and 24-monthsold) were studied. Tissues were obtained from the cerebellum and parietal, frontal, temporal cortex of the central nervous system of the rats for steroid extraction. The estradiol, progesteron, testosterone and dehydroepiandrosterone (DHEA) levels were measured by Enzyme Linked Immunosorbent Assay (ELISA). The average levels of estradiol (pg/g), progesteron (ng/g), DHEA (ng/g) and testosterone (ng/g) in the brain tissues were respectively 24.29, 4.59, 0.27, 0.92 in the newborn-rats; 4.18 ± 1.10, 1.54 ± 0.30, 0.28 ± 0.01, 0.57 ± 0.10 in the 1 month-old-rats; 11.02 ± 1.10, 2.96 ± 0.30, 0.27 ± 0.01, 0.61 ± 0.10 in the 6 month-old-rats; 15.80 ± 1.10, 4.80 ± 0.30, 0.28 ± 0.10, 0.67 ± 0.10 in the 12 monthold- rats; 20.07 ± 1.10, 4.12 ± 0.30, 0.28 ± 0.01, 0.55±0.10 in the 24 month-old-rats. The myelin basic protein levels were determined by immunohistochemical staining and an elevation was observed in conjunction with the aging process. The results of the study indicate that the alterations in MBP, DHEA, progesterone, testosterone and estrodiol concentrations in the central nervous system of the rats during aging can be considered fundamental for future animal and human studies.  相似文献   
24.
25.
Angiogenesis is essential for bone formation and several bone morphogenetic proteins (BMPs) have been shown to induce angiogenesis through osteoblast-derived vascular endothelial growth factor (VEGF)-A. Growth differentiation factor-5 (GDF-5) is a member of the BMP family expressed in bone and known to induce angiogenesis in vivo. In this study, the effects of GDF-5 on osteogenic differentiation and expression of VEGF-related genes were determined using rat bone marrow stromal cells. GDF-5 stimulated osteogenic differentiation. It also upregulated the expression of VEGF-A after 3 hr, accompanied by a trend of decrease in its receptor VEGFR-2 at 6 and 24 hr. VEGF-D and its receptor VEGFR-3 showed peak expression at later time points. This regulation may be further controlled by neuropilin 2 that exhibited a parallel profile to VEGF-D. These observations indicate that GDF-5 stimulates osteogenic differentiation and has a potential to induce angiogenesis through osteoblast-derived VEGF-A in bone.  相似文献   
26.
Stigma towards mental illness and addictive disorders is a global problem and one of the main obstacles in tackling this issue remains the effective integration of mental health services into primary health care (PHC). In Latin America, information has significantly increased on the existence of stigma; however, little is known about effective interventions to prevent stigma and promote recovery-oriented practices in PHC. The aim of this study is to understand the existing evidence regarding mental health stigma in PHC with a special focus on the Latin American region. A scoping review of the literature related to mental health stigma in PHC was conducted. Two hundred and seventeen articles were evaluated; 74 met inclusion criteria and 14 additional articles were selected from references of search results. Results were subdivided into five different perspectives: users, family members and significant others, health professionals, contextual factors, and potential effective interventions. Only nine studies were based in Latin America, and only one described an intervention to reduce stigma in mental health services, not specifically in PHC. We found an urgent need to develop interventions to understand and reduce stigma in PHC settings, especially in Latin America.  相似文献   
27.
Idiopathic osteosclerosis (IO) is described as a localized no expansible radiopacity with unknown etiology. The IO is generally asymptomatic and could appear as round, elliptical or irregular in shape. The internal aspect is usually uniformly radiopaque. IO should be distinguished from condensing osteitis of dental origin, or other alveolar bone related radiopacities such as periapical cemental dysplasia. This condition may cause changes in tooth position or problems during orthodontic treatment. The purpose of the present study is to report a case of tooth resorption caused by ectopic eruption rote caused by IO. This condition represents a rare complication of IO.  相似文献   
28.
Metabolic myopathies due to disorders of lipid metabolism are a heterogeneous group of diseases. Newborns may present with hypotonia and convulsions, while progressive proximal muscle weakness or recurrent episodes of muscle weakness accompanied by rhabdomyolysis/myoglobinuria may be seen in older ages. There is little knowledge on detection of disorders of lipid metabolism by acylcarnitine profile (ACP) analysis by tandem mass spectrometry outside the neonatal period particularly in cases with recurrent rhabdomyolysis first presenting in adolescence and adulthood. Two adolescent female cases presented with episodes of rhabdomyolysis and muscle weakness. A 13-year-old patient had five episodes of rhabdomyolysis triggered by infections. Tandem mass spectrometry was normal. A 16-year-old female patient was hospitalized eight times due to recurrent rhabdomyolysis. Increased levels of C14:2, C14:1, and C14 were determined in tandem mass spectrometry. Final diagnoses were carnitine palmitoyltransferase II (CPT II) deficiency and very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency. Increased serum levels of long-chain acylcarnitine can guide to the diagnosis of lipid metabolism disorders. Serum ACP should be performed before enzyme assay and genetic studies.  相似文献   
29.
30.

Aim

Kidney hypoxia can predispose to the development of acute and chronic renal failure in diabetes. Ischaemia–reperfusion injury (IRI) causes inflammation, and diabetes is known to exacerbate this inflammatory response in the kidney, whereas alarmin IL-33 could act as an innate immune mediator during kidney IRI. Thus, the present study examined the impact of genetic IL-33 receptor ST2 deficiency (ST2?/?) on renal IRI in euglycaemic and hyperglycaemic mice.

Methods

Hyperglycaemia was induced with streptozotocin (STZ) in adult male C57BL/6JRj wild-type (WT) mice and ST2?/? mice. Unilateral renal IRI was achieved 3 months after STZ treatment by left kidney nephrectomy (non-ischaemic control kidney) and clamping of the right renal artery for 32 min in STZ- and vehicle-treated animals. At 24 h after reperfusion, renal function and injury were determined by levels of plasma creatinine, blood urea nitrogen (BUN) and histological tubule scores. Also, in a complementary pilot clinical study, soluble ST2 concentrations were compared in diabetics and non-diabetics.

Results

Urinary albumin was significantly increased in STZ-induced hyperglycaemic mice, regardless of genotypic background. At 24 h post-ischaemia, plasma creatinine, BUN and tubular injury were significantly reduced in ST2?/? mice compared with vehicle-treated WT mice, but this protective effect was lost in the STZ-induced hyperglycaemic ST2?/? animals. Plasma concentrations of soluble ST2 were significantly greater in type 2 diabetes patients vs non-diabetics.

Conclusion

Our data suggest that the IL-33/ST2 pathway exerts differential effects depending on the glucose environment, opening-up new avenues for future research on alarmins and diabetes in ischaemia-related diseases.  相似文献   
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