The Impact of Repeated Steam Sterilization Cycles on the Efficacy of Chairside Adjustment Kits for Polishing Monolithic Multi-Layered Zirconia Dental Restoration Material.

BACKGROUND Before insertion, chairside adjustment kits are heat sterilized for positioning and polishing dental restorations. This study aimed to evaluate the effects of 2 steam sterilization cycles on the efficacy of polishing highly translucent monolithic zirconia (HTMLZ) dental restoration material. MATERIAL AND METHODS 100 HTMLZ disc-shaped specimens were adjusted (grinding, finishing, polishing) with EVE Diacera kit. Two steam sterilization techniques [standard (Gp S), immediate/flash (Gp (F)] of CAK were further subgrouped based on number of sterilization cycles [cycle 1 (control), cycle 5, 10, 15, and 20 (experimental)] (n=10 each). Each subgroup accordingly was evaluated for average surface roughness (Ra) and root mean square roughness (Rq) using a profilometer. Mean and standard deviation of 5 subgroups were statistically analyzed using one-way ANOVA/post hoc Tukey's test. Scanning electron microscopy complemented Ra, Rq measurements. Statistical differences of P≤0.05 were considered significant. RESULTS HTMLZ specimens in both groups showed increased (Ra/Rq) values after repeated sterilization of EVE Diacera kit, with Gp F showing lesser increase than Gp S (20 cycles). Gp F at 10 cycles and Gp S at 15 cycles showed clinically unacceptable roughness threshold (0.25 µm). Differences between subgroups for Ra and Rq values were significant (P≤0.05) with less differences within groups observed in early cycles (1, 10). Results validate the manufacturer's recommendations of using flash sterilization/10 cycles for EVE Diacera kit. CONCLUSIONS Repeated sterilization reduces efficacy of chairside adjustment kit to produce smooth surfaces on HTMLZ. This study recommends flash sterilization to a maximum of 10 times to get the clinically acceptable results of Ra and Rq.

Assessment of risk factors associated with multidrug-resistant organism infections among patients admitted in a tertiary hospital - a retrospective study.

Background: Bacterial resistance has become a global health concern. To treat suspected multidrug resistant organisms (MDROs), physicians first use broad-spectrum antibiotics; however, this increases the chance of developing antimicrobial resistance. Thus, defining the risk factors for MDROs could aid in the selection of the ideal initial antimicrobial therapy and improve clinical outcomes. Objective: This study aimed to identify the common risk factors for MDRO infection among patients admitted to King Fahad Hospital (KFH) and to analyze the comorbidity factors associated with MDRO infections. Methods: This retrospective, observational, case-control study included adult patients ≥ 18 years old admitted to KFH between 1st of January to 31st of March 2021, with positive microbial culture. Pediatric patients, outpatients, or patients with only positive fungal cultures were excluded. Data were obtained from the KFH laboratory MDRO documenting database. Results: Two hundred and seventy patients were included in this study: 136 in the study group and 134 in the control group. Among patients, 167 (61.9 %) were males and 184 (68.1%) were 18 to 65 years old. The use of drugs such as cotrimoxazole, amikacin, and imipenem (OR = 4.331, C. I. of OR:1.728, 10.855, p = 0.002) were significantly associated with MDRO infections, whereas cefazolin was associated with a lower risk of MDRO infections (OR = 0.080, C.I. of OR:0.018, 0.347, p < 0.001). The intensive care unit showed higher odds of significant association with MDRO infections than those of the surgical unit (odds ratio [OR] = 8.717, 95% C.I. of OR: 3.040, 24.998, p < 0.001). Patients who previously consumed acid-suppressive medications showed higher odds of developing MDRO infections (OR = 5.333, C.I. of OR: 2.395, 11.877, p < 0.001). Conclusion: The most significant comorbidities were diabetes, hypertension, antibiotic use prior to hospitalization and the use of cotrimoxazole, amikacin and imipenem among other antibtiotics was mostly associated with MRDO infections. This study revealed an increasing trend of MDRO infections and a positive correlation with the incidence of strokes and mortality, which highlights the importance of understanding the risk factors for MDRO infections.

Early Versus Late Antipseudomonal ß-Lactam Antibiotic Dose Adjustment in Critically Ill Sepsis Patients With Acute Kidney Injury: A Prospective Observational Cohort Study.

Background: Acute kidney injury (AKI) is a common complication of sepsis, contributing to an increased mortality rate. However, some studies have demonstrated that renal function improves in sepsis patients with AKI within 48 hours, raising questions about the necessity for early antibiotic adjustment. This study evaluates the association between the timing of antipseudomonal ß-lactam dose adjustment and the outcomes of critically ill sepsis patients with AKI. Methods: A prospective, multicenter observational study of critically ill patients aged ≥18 years admitted to the intensive care unit with sepsis and AKI and started on antipseudomonal ß-lactam therapy. After the initial dose, eligible patients were grouped as early ß-lactam antibiotic (E-BLA) or late ß-lactam antibiotic (L-BLA) dose adjustments based on the administration of subsequent renally adjusted doses within 24 hours and after 24 hours of sepsis recognition, respectively. The main outcome of interest was in-hospital mortality. Results: Among 1185 patients screened, 224 (mean age, 62.7 ± 16.8 years; 62% were male) met inclusion criteria. Eighty-four and 140 patients were included in the E-BLA and L-BLA groups, respectively. Approximately half of the cohort presented with AKI stage II, and piperacillin-tazobactam was prescribed as initial empirical therapy in more than 50% of the cohort. In the multivariable Cox proportional hazards model, L-BLA was associated with a significant reduction in in-hospital mortality compared to E-BLA (hazard ratio, 0.588 [95% confidence interval, .355-.974]). Conclusions: In sepsis patients with AKI, L-BLA was associated with in-hospital mortality benefits.

Buccaneer model building with neural network fragment selection.

Tracing the backbone is a critical step in protein model building, as incorrect tracing leads to poor protein models. Here, a neural network trained to identify unfavourable fragments and remove them from the model-building process in order to improve backbone tracing is presented. Moreover, a decision tree was trained to select an optimal threshold to eliminate unfavourable fragments. The neural network was tested on experimental phasing data sets from the Joint Center for Structural Genomics (JCSG), recently deposited experimental phasing data sets (from 2015 to 2021) and molecular-replacement data sets. The experimental results show that using the neural network in the Buccaneer protein-model-building software can produce significantly more complete protein models than those built using Buccaneer alone. In particular, Buccaneer with the neural network built protein models with a completeness that was at least 5% higher for 25% and 50% of the original and truncated resolution JCSG experimental phasing data sets, respectively, for 28% of the recently collected experimental phasing data sets and for 43% of the molecular-replacement data sets.

Severe Insomnia Induced by Isotretinoin Use for the Management of Acne Vulgaris: A Rare Side Effect.

Isotretinoin has been widely prescribed for the management of moderate to severe acne vulgaris worldwide. It has been associated with different sleep disorders, mainly sleep apnea and hypersomnia. To our knowledge, only one study has found an association between isotretinoin use and insomnia. In addition, psychiatric disorders, such as psychosis and depression, have been linked to the use of isotretinoin previously. Here, we present a case of a 21-year-old male patient with severe acne vulgaris that underwent a therapeutic course of isotretinoin. During the course of treatment, he developed severe insomnia and depression. By reducing the daily dose, his insomnia was treated, as well as his depression. This case led to the conclusion that isotretinoin is associated with severe insomnia, and the severity of insomnia is dose-dependent.

Bilateral, Symmetrical, Congenital Becker's Nevus Melanosis: A Rare Presentation and Review of the Literature.

Becker's nevus, also known as Becker's melanosis or Becker's pigmentary hamartoma, is a concurrent melanosis first described by S. William Becker. It is a type of acquired hyperpigmentation characterized by well-defined, unilateral lesions with regular borders. It is associated with hypertrichosis and hyperpigmented brownish patches with a mean diameter of 15 cm. The shoulder, scapular area, and upper arms are the most commonly affected areas, but it can occur on any area of the body, including the forehead, face, neck, lower trunk, extremities, and buttocks. The lesion usually appears around puberty, and males are more likely to be affected than females. A 27-year-old male of Arabic descent who was medically free presented to the dermatology clinic complaining of bilateral, symmetrical, hyperpigmented patches on the upper back. The lesions started almost at birth, gradually growing in size and darkening in color over time. On local skin examination, the lesions were bilateral, symmetrical, hyperpigmented patches on the upper back. They were both homogeneous and brown in color with irregular borders and blotchy hyperpigmented macules on both sides of the upper back associated with sparse hair development. Histopathological examination revealed epidermal hyperkeratosis, acanthosis, and focal regular elongation of rete ridges with clubbing. Increased basal layer pigmentation was noticed. The dermis showed focal areas with pigment incontinence. Based on the above clinicopathological findings, the patient was diagnosed with Becker's melanosis. He was referred to the laser clinic for further treatment.

Predicting the performance of automated crystallographic model-building pipelines.

Proteins are macromolecules that perform essential biological functions which depend on their three-dimensional structure. Determining this structure involves complex laboratory and computational work. For the computational work, multiple software pipelines have been developed to build models of the protein structure from crystallographic data. Each of these pipelines performs differently depending on the characteristics of the electron-density map received as input. Identifying the best pipeline to use for a protein structure is difficult, as the pipeline performance differs significantly from one protein structure to another. As such, researchers often select pipelines that do not produce the best possible protein models from the available data. Here, a software tool is introduced which predicts key quality measures of the protein structures that a range of pipelines would generate if supplied with a given crystallographic data set. These measures are crystallographic quality-of-fit indicators based on included and withheld observations, and structure completeness. Extensive experiments carried out using over 2500 data sets show that the tool yields accurate predictions for both experimental phasing data sets (at resolutions between 1.2 and 4.0 Å) and molecular-replacement data sets (at resolutions between 1.0 and 3.5 Å). The tool can therefore provide a recommendation to the user concerning the pipelines that should be run in order to proceed most efficiently to a depositable model.

Pairwise running of automated crystallographic model-building pipelines.

For the last two decades, researchers have worked independently to automate protein model building, and four widely used software pipelines have been developed for this purpose: ARP/wARP, Buccaneer, Phenix AutoBuild and SHELXE. Here, the usefulness of combining these pipelines to improve the built protein structures by running them in pairwise combinations is examined. The results show that integrating these pipelines can lead to significant improvements in structure completeness and Rfree. In particular, running Phenix AutoBuild after Buccaneer improved structure completeness for 29% and 75% of the data sets that were examined at the original resolution and at a simulated lower resolution, respectively, compared with running Phenix AutoBuild on its own. In contrast, Phenix AutoBuild alone produced better structure completeness than the two pipelines combined for only 7% and 3% of these data sets.

AUC- vs. Trough-Guided Monitoring of Vancomycin in Infants.

OBJECTIVE: Improving vancomycin therapy with therapeutic drug monitoring is recommended. Over the past few years, a few studies have demonstrated that trough concentrations may not be the optimal parameter for monitoring vancomycin concentration and Area under the curve (AUC) should be used instead. In this study authors evaluate two methods to estimate the AUC. The first method is based on linear regression using only a trough concentration. The second method uses a simplified two-sample equation-based strategy to estimate the AUC. METHODS: Data from 70 infant patients were collected retrospectively from their medical records at King Saud University Medical City. The prediction accuracy for vancomycin therapy monitoring was optimized by comparing the two methods for the AUC calculation, the simple linear regression and simplified two-sample equation-based strategy. RESULTS: The target AUC > 400 µg × h/ml was achieved in 10%, 71%, and 100% of patients with trough concentration ranges of 5-10, 10-15, and > 15 µg/ml, respectively. There was a strong correlation between the predicted and observed AUC calculated using the simplified two-sample equation-based strategy (R2 = 0.91, bias = -3.9%, precision =12%). CONCLUSIONS: The target AUC > 400 µg × h/ml can be achieved at trough concentrations <15 µg/ml in most patients. Targeting trough concentrations >15 can lead to overdoing and increase risk of nephrotoxicity. The authors recommend estimating the AUC using the simplified two-sample equation strategy for more precise dosing of vancomycin. Using AUC-guided dosing instead of the trough-guided approach can prevent over dosing and reduce the risk of nephrotoxicity.

Comparison of automated crystallographic model-building pipelines.

A comparison of four protein model-building pipelines (ARP/wARP, Buccaneer, PHENIX AutoBuild and SHELXE) was performed using data sets from 202 experimentally phased cases, both with the data as observed and truncated to simulate lower resolutions. All pipelines were run using default parameters. Additionally, an ARP/wARP run was completed using models from Buccaneer. All pipelines achieved nearly complete protein structures and low Rwork/Rfree at resolutions between 1.2 and 1.9 Å, with PHENIX AutoBuild and ARP/wARP producing slightly lower R factors. At lower resolutions, Buccaneer leads to significantly more complete models.