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71.
Aim:

Low-level laser therapy has still not been well established, and it is important to define a standardized protocol for the treatment of temporomandibular disorders (TMDs) using low level laser. There is no consensus on controlled clinical trials concerning the best option for laser therapy with regard to wavelength. The aim of this study was to evaluate the efficacy of red and infrared laser therapy in patients with TMD, using a randomized parallel-group double-blind trial.

Methodology:

Each hemiface of 19 subjects was randomized to receive intervention, in a total of 116 sensitive points. Pain was measured at baseline and time intervals of 24 hours, 30 days, 90 days, and 180 days after treatment. Irradiation of 4 J/cm2 in the temporomandibular joints and 8 J/cm2 in the muscles was used in three sessions.

Results:

Both treatments had statistically significant results (P<0·001); there was statistical difference between them at 180 days in favor of the infrared laser (P?=?0·039). There was improvement in 24 hours, which extended up to 180 days in both groups.

Conclusion:

Both lasers are effective in the treatment and remission of TMD symptoms.  相似文献   
72.

Objectives

The combination of sodium hypochlorite (NaOCl) and chlorhexidine (CHX) yields a “precipitate potentially toxic” (PPT). The aim of this study was to evaluate the tissue response to implanted polyethylene tubes filled with PPT-soaked fibrin sponge.

Methods

Forty rats received four polyethylene tubes each; each tube was filled with fibrin sponge soaked by 2.5 % NaOCl, 2.0 % CHX, PPT (2.5 % NaOCl plus 2.0 % CHX), or not soaked (control). The observation time points were 7, 15, 30, 60, and 90 days. At each time point, eight animals were killed, and the tubes and surrounding tissues were removed, fixed, and prepared for light microscopic analysis by performing glycol methacrylate embedding, serial cutting into 3-μm sections, and hematoxylin–eosin staining. Qualitative and quantitative evaluations of the reactions were performed. Results were statistically analyzed by Kruskal–Wallis test (p?<?0.05).

Results

All chemical solutions caused moderate reactions at 7 days. On day 30, PPT group was more cytotoxic than the control group and the CHX group (p?<?0.05). On days 15 and 60, PPT group was more cytotoxic than the control group (p?<?0.05). On day 90, there was no statistically significant difference between the different groups.

Conclusion

PPT is more cytotoxic than NaOCl and CHX alone, particularly in the short term.

Clinical significance

Protocols which suggest the use of CHX and NaOCl must be revised because this mixture produces cytotoxic product.  相似文献   
73.

Purpose

Myofibroma is a rare benign spindle cell neoplasm, and the aim of the present study was to carry out a literature review and present a clinical case of a patient with a myofibroma in the submandibular region and its management.

Conclusions

Diagnosis of myofibroma can be reached by a histopathologic and immunohistochemical analysis and surgical excision is the treatment of choice.  相似文献   
74.

Purpose

The objective of this study is to compare the ability of panoramic radiography and cone beam computed tomography (CBCT) in detecting anatomical variations of the mandibular canal and mental foramen.

Methods

One hundred twenty-seven preoperative panoramic and CBCT images were evaluated. Two oral and maxillofacial radiologists investigated the presence of bifid mandibular canals and/or additional mental foramina on the right, left, or both sides of the mandible. Intra- and interobserver reliability was determined using Cohen’s kappa coefficient. McNemar’s test compared the prevalence of mandibular anatomical variations between panoramic radiography and CBCT. The significance level was set at 0.05.

Results

Additional mental foramen and bifid mandibular canal were detected in 1.2 and 7.4 % of the panoramic radiographs and 7.4 and 9.8 % of the CBCT images, respectively. The incidence of anatomical variations on the mandibular canal was not significantly different between both imaging modalities (P?>?0.05).

Conclusions

Although CBCT provides better viewing of anatomical structures, including location, shape, and relationship with the surrounding area, panoramic radiography is a conventional imaging modality that can be used in the study of the bifid mandibular canals.  相似文献   
75.
Vascular calcification (VC) is a risk factor for cardiovascular mortality in the setting of chronic kidney disease (CKD). Pyrophosphate (PPi), an endogenous molecule that inhibits hydroxyapatite crystal formation, has been shown to prevent the development of VC in animal models of CKD. However, the possibility of harmful effects of exogenous administration of PPi on bone requires further investigation. To this end, we examined by histomorphometry the bone of CKD mice after intraperitoneal PPi administration. After CKD creation or sham surgery, 10-week-old female apolipoprotein-E knockout (apoE?/?) mice were randomized to one non-CKD group or 4 CKD groups (n = 10–35/group) treated with placebo or three distinct doses of PPi, and fed with standard diet. Eight weeks later, the animals were killed. Serum and femurs were sampled. Femurs were processed for bone histomorphometry. Placebo-treated CKD mice had significantly higher values of osteoid volume, osteoid surface and bone formation rate than sham-placebo mice with normal renal function. Slightly higher osteoid values were observed in CKD mice in response to very low PPi dose (OV/BV, O.Th and ObS/BS) and, for one parameter measured, to high PPi dose (O.Th), compared to placebo-treated CKD mice. Treatment with PPi did not modify any other structural parameters. Mineral apposition rates, and other parameters of bone formation and resorption were not significantly different among the treated animal groups or control CKD placebo group. In conclusion, PPi does not appear to be deleterious to bone tissue in apoE?/? mice with CKD, although a possible stimulatory PPi effect on osteoid formation may be worth further investigation.  相似文献   
76.

Background

Parathyroidectomy (PTx) decreases the mortality rate of refractory secondary hyperparathyroidism (rSHP) due to chronic kidney disease. A consensus regarding which techniques of PTx are associated with better outcomes is not available. The aims of this study are to evaluate the clinical and laboratory evolution of 49 hemodialysis patients with rSHP who underwent PTx using different techniques.

Methods

Patients underwent subtotal PTx (sub-PTx) or total PTx with autotransplantation (AT) of 45 (PTx-AT45) or 90 parathyroid fragments (PTx-AT90) and were followed for 12 months. We analyzed the expression of proliferating cell nuclear antigen (PCNA), calcium-sensing receptor (CasR), vitamin D receptor (VDR), fibroblast growth factor receptor-1 (FGFR1), sodium-dependent phosphate cotransporter-1 (PIT1), and Klotho in parathyroid glands.

Results

Baseline median serum intact parathyroid hormone (iPTH) levels were 1,466 (1,087–2,125) pg/mL; vascular calcification scores correlated with serum iPTH (r?=?0.529; P?=?.002) and serum phosphate levels (r?=?0.389; P?=?.028); and Klotho expression was negatively correlated with serum phosphate levels (r?=??0.4; P?=?.01). After 12 months, serum iPTH and alkaline phosphatase levels were significantly controlled in all groups, as was bone pain. The proportions of patients with serum iPTH levels within the ranges recommended by Kidney Disease: Improving Global Outcomes were similar among the treatment groups. During the hungry bone disease (HBS), patients received 3,786?g (1,412–7,580) of elemental calcium, and a trend toward a positive correlation between the cumulative calcium load at the end of follow up and VC score post-PTx was noted (r?=?0.390; P?=?.06). Two cases evolved to clinically uncontrolled hyperparathyroidism in the sub-PTx group. The expression patterns of PCNA, VDR, CasR, PIT1, FGFR1, and Klotho in parathyroid glands did not correlate with serum systemic iPTH levels or the duration of HBS.

Conclusions

All 3 operative techniques were effective at controlling rSHP, both in clinical and laboratory terms. Neither the quantity nor quality of parathyroid fragments influenced serum systemic iPTH and AT-iPTH levels. The cumulative calcium load appeared to correlate with the VC score and may have affected its progression. The effects of phosphate restriction on Klotho expression in human parathyroid glands and the subsequent decrease in FGF23 resistance must be addressed in further studies.  相似文献   
77.

Background

Acute liver failure (ALF) is a clinical syndrome that results from the abrupt loss of liver function in a patient without previous liver disease. The most frequent causes are viral hepatitis, drug induced, and autoimmune disease, but in 20% of cases no cause is identified. Carthamus tinctorius (safflower) oil is used as a dietary supplement for weight loss and antioxidant. There are 4 cases described in the literature of ALF induced by the use of this substance. The objective of this study was to report 3 cases of ALF treated at the Clinical Hospital of the State University of Campinas that suggest the use of C tinctorius oil as a probable etiologic factor.

Case Reports

The 3 patients had a diagnosis of ALF according to the King's College criteria. All had a history of ingestion of this oil for weight loss. During etiologic evaluation, viral hepatitis, autoimmune diseases, or any other drug cause were excluded, thus pointing to C tinctorius oil as the triggering factor. All 3 patients underwent liver transplantation: 2 had good postoperative evolution, and 1 died 12 days after the procedure.

Conclusions

Two cases are described in which the hepatic insufficiency induced by C tinctorius oil was successfully treated through liver transplantation. This highlights the risk of misuse of this substance for weight loss.  相似文献   
78.
The objective of this study was to evaluate the effects of LED on burns healing. Five patients with skin burns were submitted to photobiomodulation by LED, GaAsIP diode, (λ 658 nm) with 40 mW, 7 J/cm2 on every other day. Biopsies of burned skin were performed and the healing process was photographed. Patients with bilateral burns were used as self-control, having one limb being irradiated and the contralateral limb irradiated with placebo. The burns treated with LED showed higher epithelization, with keratinocytes and fibroblasts proliferation, increased collagen synthesis, decreased pain, and pruritus. In conclusion, there was a faster clinical improvement in the irradiated limbs.  相似文献   
79.

Purpose

Bone biopsy defines classical diseases that constitute the renal osteodystrophy. There is a recent concern regarding other histological findings that are not appreciated by using the turnover, mineralization, and volume (TMV) classification. Iron (Fe) overload has been considered a new challenge and the real significance of the presence of this metal in bones is not completely elucidated. Therefore, the main goal of the current study was to not only to identify bone Fe, but also correlate its presence with demographic, and biochemical characteristics.

Methods

This is a cross-sectional analysis of bone biopsies performed in 604 patients on dialysis from 2010 to 2014 in a tertiary academic Hospital.

Results

Histomorphometric findings revealed the presence of Fe in 29.1%. Fe was associated with higher levels of serum ferritin and serum calcium. No TMV status was related to Fe bone overload.

Conclusion

Our study has highlighted that the presence of Fe in one-third of bone samples has unknown clinical significance. The lack of other contemporary bone biopsy study reporting Fe prevents us from comparison. The findings presented here should be specifically addressed in a future research and will require attention prior to implementation of any clinical guideline. If any proposed treatment, however, would change the bone Fe-related morbidity is undetermined.
  相似文献   
80.
Male obesity is associated with decreased testosterone levels but the pathophysiological mechanisms behind this association are not completely understood. This study aimed to investigate the impact of hyperglycaemia/insulin resistance and sex hormone‐binding globulin (SHBG) levels on testosterone levels in a population of obese men. We investigated the impact of several clinical, anthropometric and analytic measures on testosterone levels in 150 obese males. Testosterone deficiency was present in 52.0% of the enrolled patients. This percentage dropped to 17.6% when only calculated free testosterone (FT) was accounted, as SHBG levels were correlated negatively with body mass index (r = ?.20; < .05). Older age (< .05) and higher homoeostasis model assessment of insulin resistance (HOMA‐IR) (< .01) and lower SHBG levels (< .05) were independently correlated with lower FT. Weight and fasting plasma glucose lost their statistical significance after multivariate adjustment. Patients with type 2 diabetes mellitus and pre‐diabetes had lower FT than those with normal glucose tolerance (< .05 and < .01 respectively). Insulin resistance, and not hyperglycaemia and weight per se, seems to be the main determinant of low testosterone levels in obese males. Low SHBG levels are correlated with low FT even after HOMA‐IR adjustment. This suggests that SHBG can be associated with testosterone deficiency beyond the influence of insulin resistance unlike previously reported.  相似文献   
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