The integration of Coxiella burnetii PCR testing in serum into the diagnostic algorithm of suspected acute Q fever in an endemic setting

Serum polymerase chain reaction (PCR) for the detection of Coxiella burnetii DNA has been suggested for rapid Q fever diagnosis. We evaluated the role of PCR testing in serum in the diagnosis of acute Q fever in an endemic setting. We examined patients suspected of acute Q fever tested for C. burnetii-specific serum real-time PCR in a tertiary hospital between January 2019 toand December 2022. In the first half, PCR orders were consultation-based by infectious diseases specialists, while in the second half, they were guided by serology, positive IgM2, and negative IgG1 and IgG2, indicating early acute infection. Logistic regression analyzed independent predictors for positive PCR. PCR positivity rates were calculated using various clinical criteria in the diagnostic algorithm. Out of 272 patients, 13 (4.8%) tested positive and 130 exhibited serologically suspected early infection. Presentation during April-July and aspartate aminotransferase (AST) > 3× upper normal limit (UNL) were independently associated with positive PCR with an odds ratio (OR) = 15.03 [95% confidence interval (CI), 1.58-142.46], P = 0.018 and OR = 55.44 [95% CI, 6.16-498.69], P < 0.001, respectively. PCR positivity rate was 8.5% in serologically suspected early infection vs 1.4% in other serology, yielding OR = 6.4 [95% CI, 1.4-29.7], P = 0.009. Adding AST > 3× UNL increased OR to 49.5 [95% CI, 5.9-408.7], P ≤ 0.001 reducing required PCR tests for a single acute Q fever case from 11.8 to 3. Elevated AST in serologically suspected early Q fever is proposed to be used in a diagnostic stewardship algorithm integrating PCR in serum in an endemic setting.

IMPORTANCE

Our study suggests in a diagnostic stewardship approach the integration of molecular testing (Coxiella burnetii targeted PCR) for the diagnosis of acute Q fever in a reliable time in the endemic setting. Integrating PCR detecting Coxiella burnetii in serum in routine testing of suspected early acute Q fever based on serology result increased the PCR positivity rate significantly. Adding increased transaminases optimizes PCR utility which is highly requested particularly in endemic areas.

Effect of ferrule height and distribution on the fracture resistance of endodontically treated premolars

Objective

To evaluate the effect of varying ferrule height and distribution on the fatigue resistance and fracture strength of endodontically treated premolars.

Materials and Method

Thirty-two extracted human premolars were endodontically treated and prepared to receive all-ceramic crowns. Teeth were randomly divided into two groups. The occluso-cervical height was reduced to 2 mm and 4 mm for the 1^st and 2^nd groups, respectively. According to the ferrule distribution, samples in each group were randomly divided into two subgroups with inadequate ferrule on 1 or 2 proximal walls, respectively. Coronal tooth structure was built-up to 4 mm using a core build-up material retained by a fiber post. The CEREC system (Sirona) was used to design and mill lithium-disilicate crowns. All posts and crowns were cemented to their respective teeth using self-adhesive universal resin cement. All crowns were subjected to cyclic loading in a universal testing machine (Instron) (20-100N, 100,000 cycles, 20Hz). After fatigue, crowns were loaded to fracture. Fracture load data were analyzed using two-way ANOVA at α = 0.05.

Results

All crowns passed the fatigue testing without any signs of fracture or crack. Two-way ANOVA revealed a statistically significant effect of the number of missing walls (P < 0.05) on the fracture load, but not the ferrule height or the interaction terms. Samples with one missing wall showed higher fracture load in comparison to samples with two missing walls.

Conclusion

The number of missing walls, not the ferrule height, has a significant effect on the fracture load of the lithium-disilicate crowns restoring endodontically treated premolars.

Supercomputer-Based Ensemble Docking Drug Discovery Pipeline with Application to Covid-19

We present a supercomputer-driven pipeline for in silico drug discovery using enhanced sampling molecular dynamics (MD) and ensemble docking. Ensemble docking makes use of MD results by docking compound databases into representative protein binding-site conformations, thus taking into account the dynamic properties of the binding sites. We also describe preliminary results obtained for 24 systems involving eight proteins of the proteome of SARS-CoV-2. The MD involves temperature replica exchange enhanced sampling, making use of massively parallel supercomputing to quickly sample the configurational space of protein drug targets. Using the Summit supercomputer at the Oak Ridge National Laboratory, more than 1 ms of enhanced sampling MD can be generated per day. We have ensemble docked repurposing databases to 10 configurations of each of the 24 SARS-CoV-2 systems using AutoDock Vina. Comparison to experiment demonstrates remarkably high hit rates for the top scoring tranches of compounds identified by our ensemble approach. We also demonstrate that, using Autodock-GPU on Summit, it is possible to perform exhaustive docking of one billion compounds in under 24 h. Finally, we discuss preliminary results and planned improvements to the pipeline, including the use of quantum mechanical (QM), machine learning, and artificial intelligence (AI) methods to cluster MD trajectories and rescore docking poses.

Supercomputer-Based Ensemble Docking Drug Discovery Pipeline with Application to Covid-19

We present a supercomputer-driven pipeline for in-silico drug discovery using enhanced sampling molecular dynamics (MD) and ensemble docking. We also describe preliminary results obtained for 23 systems involving eight protein targets of the proteome of SARS CoV-2. THe MD performed is temperature replica-exchange enhanced sampling, making use of the massively parallel supercomputing on the SUMMIT supercomputer at Oak Ridge National Laboratory, with which more than 1ms of enhanced sampling MD can be generated per day. We have ensemble docked repurposing databases to ten configurations of each of the 23 SARS CoV-2 systems using AutoDock Vina. We also demonstrate that using Autodock-GPU on SUMMIT, it is possible to perform exhaustive docking of one billion compounds in under 24 hours. Finally, we discuss preliminary results and planned improvements to the pipeline, including the use of quantum mechanical (QM), machine learning, and AI methods to cluster MD trajectories and rescore docking poses.

Hemodynamic performance of stentless porcine bioprosthesis and mechanical bileaflet prosthesis using dobutamine stress echocardiography

Currently available aortic valve prostheses have satisfactory hemodynamic performance during rest, but with exercise they possess different responses. The objective was to compare the hemodynamic response of the stentless porcine bioprosthesis (SP) and the mechanical bileaflet prosthesis (MB) at rest and during peak exercise using dobutamine stress echocardiography (DSE). DSE was used to evaluate the effective orifice area index (EOAI), peak and mean pressure gradients at rest and during maximum stress in 15 patients with SP (group T, mean age, 30.9 year) and another 15 patients with MB (group M, mean age, 28.6 year). The increment in pressure gradient (mean/peak) was significantly less in patients with SP than those with MB (P <.01). The EOAI did not change with exercise. At rest, both valve substitutes have satisfactory hemodynamics, but during exercise the stentless porcine bioprosthesis has better hemodynamics because it is less obstructive that justifies its use in young population.

Serum nickel, copper and zinc in Norplant users

Changes in serum nickel, copper and zinc were evaluated in 45 Norplant users. Two groups were selected for this study. Group I included 15 regularly menstruating females as controls and as short-term users (90 days after Norplant insertion). Group II included 30 Norplant users for one year or more as long-term users. These elements were determined by atomic absorption spectrophotometry. Serum nickel showed no significant change in short-term nor in long-term users when compared to the control group or to each other. Serum copper and zinc revealed a significant increase in short-term users for a short period of time, which returned to normal levels in long-term users. There was disappearance of the cyclic changes in serum copper and zinc concentrations on comparing their levels in ovulatory to non-ovulatory Norplant users. The use of Norplant has no deleterious effects on serum levels of nickel, copper and zinc.

A family with spondyloepimetaphyseal dwarfism: a 'new' dysplasia or Kniest disease with autosomal recessive inheritance?

We present an Arab family with some features of Kniest disease. The proband was a six year old boy with rhizomelic short limbed dwarfism, 'dish-like' facies, cleft palate, deafness, and camptodactyly. Most radiological changes were compatible with Kniest disease. Two younger sibs, similarly affected, had died at a few months old, and the pedigree shows strong evidence of autosomal recessive inheritance, unlike previously reported cases of Kniest disease which have shown autosomal dominant inheritance.

Serum nickel concentration in normal menstrual cycle and after combined contraceptive pill

Serum nickel concentration in the different phases of the menstrual cycle and after use of a combined contraceptive pill (Anovlar) was determined by atomic absorption spectrophotometry. Twenty ovulating females had their serum nickel level measured on day 5 and on day 27 of their cycle. Forty females using Anovlar for 6 months and 40 females using it for more than 3 years had their serum nickel determined. The serum nickel concentration of the non-pill users was higher on day 5 (2.52 +/- 0.46 micrograms/L) than on day 27 (2.21 +/- 0.37 micrograms/L p less than 0.05). In long-term users, the serum nickel (0.98 +/- 0.38 microgram/L) was less than the short-term users (2.38 +/- 0.35 micrograms/L, p less than 0.01) and the non-users (p less than 0.01). There was a negative correlation between the duration of pill use and the serum nickel level (r = -0.44, p less than 0.01). The significance of the decreased serum nickel level with long-term pill use remains to be determined.

Spondyloepiphyseal dysplasia tarda with progressive arthropathy

We present a family with numerous first cousin marriages and several members affected with spondyloepiphyseal dysplasia tarda with progressive arthropathy causing severe crippling and deformity. The extensive pedigree provides strong evidence for autosomal recessive inheritance.

Blunt abdominal trauma and hollow viscus injury in children: the diagnostic value of plain radiography

Although blunt abdominal trauma is common in children, the G-I tract is involved only rarely. However, this paper deals with a series of 24 cases in whom a hollow viscus was injured. We present the radiological and operative findings as well as the results of subsequent radiological workup in patients who had no surgery. Contrary to the recent trend which stresses early abdominal CT as critically important for guiding treatment we have retained a more conservative attitude. Our present protocol includes plain radiography frequently combined with sonographic screening of the abdomen. In patients with stable vital signs and when necessary, we follow up with scintigraphy. CT is reserved for complicated cases with obscure clinical manifestations which do not fit the plain radiological findings and also cases running an unexpected course.

Arthro-osteo-renal dysplasia. Report of a case

A rare case of bone dysplasia with moderate modelling anomalies of the long bones, joint dislocation, osteolysis, a congenital calvarial defect, a patent ductus arteriosus, a mild degree of hypospadias and hypertensive renal cystic dysplasia is presented. In spite of many similarities with the Hajdu - Cheney Syndrome (HCS), important dissimilarities indicate that this case may be either an extreme variant of HCS, or a closely related, separate entity for which the term Arthro-Osteo-Renal Dysplasia is proposed.

Effect of topically applied acidulated phosphate fluoride on dental caries

A 4-year clinical trial was conducted to determine the effect on dental caries incidence of the use of acidulated phosphate fluoride (APF 1.23%). 1,653 Egyptian schoolchildren aged 8 years started the trial. Dental caries was assessed annually by clinical examinations. 1,027 children completed the study. After 4 years, the children in the study group showed a mean of 2.58 DMF teeth and 2.68 DMF surfaces. Those in the control group showed 2.58 and 2.67, respectively. No significant reduction in the caries increment was observed at 0.05 level. The findings of this study suggest that topical application of fluoride does not decrease pit and fissure caries.