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131.
Despite the nomenclature suggested to be a tumor, torus palatinus (TP) is an overgrowth of the bone in the palatal region and represents an anatomic variation. Its prevalence varies among the population studied and its etiology is still unclear; however, it seems to be a multifactorial disorder with genetics and environmental involvement. Surgical removal of the TP is indicated in the following circumstances: (1) deglutition and speech impairment, (2) cancer phobia, (3) traumatized mucosa over the torus, and (4) prosthetic reasons. The aim of this case report is describe cases that occurred in two sisters, emphasizing the genetic etiology of this anatomic variation. In addition, intra-oral exam and computed tomography scan (axial, coronal and sagittal view) provided a detailed assessment of the TP and elimination of other possible diagnoses, furthermore allowed a better analyzes of the anatomic relation with adjacentes structures. No surgical removal was indicated for both cases.  相似文献   
132.
Plant growth-promoting bacteria are a promising alternative to improve agricultural sustainability. Gluconacetobacter diazotrophicus is an osmotolerant bacterium able to colonize several plant species, including sugarcane, coffee, and rice. Despite its biotechnological potential, the mechanisms controlling such osmotolerance remain unclear. The present study investigated the key mechanisms of resistance to osmotic stress in G. diazotrophicus. The molecular pathways regulated by the stress were investigated by comparative proteomics, and proteins essential for resistance were identified by knock-out mutagenesis. Proteomics analysis led to identify regulatory pathways for osmotic adjustment, de novo saturated fatty acids biosynthesis, and uptake of nutrients. The mutagenesis analysis showed that the lack of AccC protein, an essential component of de novo fatty acid biosynthesis, severely affected G. diazotrophicus resistance to osmotic stress. Additionally, knock-out mutants for nutrients uptake (Δtbdr and ΔoprB) and compatible solutes synthesis (ΔmtlK and ΔotsA) became more sensitive to osmotic stress. Together, our results identified specific genes and mechanisms regulated by osmotic stress in an osmotolerant bacterium, shedding light on the essential role of cell envelope and extracytoplasmic proteins for osmotolerance.  相似文献   
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Patients with mucopolysaccharidosis type VI (MPS VI) present with a wide range of disease severity and clinical manifestations, with significant functional impairment and shortened lifespan. Enzyme replacement therapy (ERT) with galsulfase has been shown to improve clinical and biochemical parameters including patient survival, quality of life and growth. The present study is a resurvey of 34 Brazilian MPS VI patients with rapidly progressive disease (classical phenotype) who initiated ERT with galsulfase under five years of age and had been on ERT until data collection in 2019, with few exceptions (n = 4 patients who died before 2019).Anthropometric measures, urinary glycosaminoglycans, and data regarding cardiac, orthopedic, neurologic, sleep apnea, hearing and ophthalmologic outcomes were filled in by specialists. Pubertal development, clinical complications, hospitalizations, and surgeries were also assessed.In this resurvey study, treatment with galsulfase has shown to be safe and well tolerated in MPS VI patients who initiated ERT under the age of 5 years and who have been undergoing ERT for approximately 10 years. Mortality rate suggests that early initiation of ERT may have a positive impact on patients' survival, improving but not preventing disease progression and death. MPS VI patients on ERT also showed improved growth velocity and the pubertal development was normal in all surviving patients.Follow-up data on pneumonia and hospitalization suggest that early ERT may have a protective effect against major respiratory complications. Cardiac valve disease progressed since their prior evaluation and spinal cord compression was observed in a large number of patients, suggesting that these disease complications were not modified by ERT.  相似文献   
135.
Objective

To answer the question: What do we know so far about the clinical performance of short implants (≤ 7 mm) when compared to standard length implants in vertically augmented bone, as well as which is the overall confidence of the systematic reviews (SRs) about this topic?

Materials and methods

An overview of SRs was conducted. The searches were performed in six electronic databases and grey literature. SRs about short (≤ 7 mm) versus standard dental implants performance in vertically augmented bone were included. The assessed outcomes were marginal bone loss (MBL), implant survival (IS), prosthetic (PC) and biological complications (BC), costs, surgical time, and patient satisfaction. AMSTAR 2 was used to evaluate the overall confidence of included SRs.

Results

Thirteen SRs were included. Nine of twelve SRs reported a lower MBL for the short implant group. All the included SRs showed no difference in the IS between groups. A higher rate of BC was reported for standard-length implants in four out of five SRs. No differences regarding PC were reported in four of five SRs. Information related to patient preference, cost, and surgery time were underreported. The confidence evaluation of the SRs was stratified as low for five SRs and critically low for eight SRs.

Conclusions

In an overall low-to-very low confidence levels, short implants appear to perform better in the mid-term (up to 5 years) than standard dental implants associated with vertical bone augmentation regarding MBL and BC, but they have a similar performance regarding IS rates and PC. There is an imperative need to improve the methodological quality of SRs, and efforts should focus on conducting RCTs to broaden the knowledge on this topic.

Clinical relevance

Short implants could represent a viable, simpler, and less invasive treatment when available bone height is limited.

  相似文献   
136.
There has been a strong and urgent demand to diagnose community transmission-driven coronavirus disease 2019 (COVID-19) after it crossed borders. A large number of rapid and accurate tests and diagnoses are required at drive-through test stations, community clinics and hospitals. Isothermal amplification technology, such as loop-mediated isothermal amplification (LAMP) and recombinase polymerase amplification (RPA), provides excellent alternatives for resource limited test environments. LAMP has been shown to be comparable with polymerase chain reaction (PCR) and can be performed in less than 30 min by non-laboratory staff without ribonucleic acid (RNA) extractions commonly associated with PCR. LAMP tests on assays with SARS-CoV-2 and other pathogenic microorganisms, such as Dengue, Malaria, and Influenza viruses and Helicobacter pylori show color changes allowing test results to be interpreted by the color change of the assays. However, visual inspection of a large number of assays is prone to human error and manual record keeping makes test result tracking for an epidemiologic investigation very difficult and inefficient. The epidemiologic investigation is an essential part of the fight against community transmission-driven viruses. We have developed a very accurate and reliable, human error free, tablet PC-based portable device for colorimetric determination of assays including SARS-CoV-2 and other pathogenic microorganisms.

There has been a strong and urgent demand to diagnose community transmission-driven coronavirus disease 2019 (COVID-19) after it crossed borders. Tablet PC-based portable device for colorimetric determination and 3D printed sample holders.  相似文献   
137.
138.
Clinical Oral Investigations - To evaluate and compare irrigant distribution throughout the root canal system of mesial roots of mandibular molars after application of distinct adjunctive irrigant...  相似文献   
139.
The International Journal of Cardiovascular Imaging - There is conflicting evidence regarding the significance of iatrogenic atrial septal defects (iASDs) after transseptal puncture during...  相似文献   
140.
The reaction of O2 with a Ru13@Pt42 core–shell particle consisting of a Ru13 core and a Pt42 shell was theoretically investigated in comparison with Pt55. The O2 binding energy with Pt55 is larger than that with Ru13@Pt42, and O–O bond cleavage occurs more easily with a smaller activation barrier (Ea) on Pt55 than on Ru13@Pt42. Protonation to the Pt42 surface followed by one-electron reduction leads to the formation of an H atom on the surface with considerable exothermicity. The H atom reacts with the adsorbed O2 molecule to afford an OOH species with a larger Ea value on Pt55 than on Ru13@Pt42. An OOH species is also formed by protonation of the adsorbed O2 molecule, followed by one-electron reduction, with a large exothermicity in both Pt55 and Ru13@Pt42. O–OH bond cleavage occurs with a smaller Ea on Pt55 than on Ru13@Pt42. The lower reactivity of Ru13@Pt42 than that of Pt55 on the O–O and O–OH bond cleavages arises from the presence of lower energy in the d-valence band-top and d-band center in Ru13@Pt42 than in Pt55. The smaller Ea for OOH formation on Ru13@Pt42 than on Pt55 arises from weaker Ru13@Pt42–O2 and Ru13@Pt42–H bonds than the Pt55–O2 and Pt55–H bonds, respectively. The low-energy d-valence band-top is responsible for the weak Ru13@Pt42–O and Ru13@Pt42–OH bonds. Thus, the low-energy d-valence band-top and d-band center are important properties of the Ru13@Pt42 particle.

In this theoretical study by DFT computations, characteristic features of the Ru13@Pt42 core–shell particle in O2 activation are clearly discussed in comparison with Pt55.  相似文献   
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