Dissemination and genome characterization of a human adenovirus F41 in a patient with B-Cell lymphoma.

Adenovirus (HAdV) F41 is a common cause of gastroenteritis and has rarely been reported associated with disseminated disease. In this report, an adult patient with a history of ulcerative colitis, cryptogenic cirrhosis, stage III adenocarcinoma, high-grade diffuse large B-cell lymphoma on chemotherapy was diagnosed with disseminated adenovirus infection. HAdV DNA was quantified in stool, plasma, and urine with viral loads of 7, 4, and 3 log10 copies/mL, respectively. The patient's course was rapidly progressive and he passed away 2 days after initiation of antiviral therapy. The patient's infecting virus was characterized as HAdV-F41 by whole genome sequencing.

Histologic Evaluation of the Triceps Brachii Tendon Insertion: Implications for Triceps-Sparing Surgery.

PURPOSE: Triceps detachment and olecranon osteotomy are 2 techniques used to enhance exposure in elbow surgery. Both the techniques can potentially add considerable morbidity and lengthen the recovery after surgery. Triceps-sparing surgery can potentially mitigate those issues. The purpose of this study was to evaluate the triceps tendon insertion at a histologic level to help improve triceps-sparing surgical techniques used in elbow trauma and arthroplasty. METHODS: Seventeen fresh-frozen cadaveric elbow specimens were collected. The olecranon and its soft tissue attachments were isolated. We performed gross measurements and sectioned the specimens for histologic evaluation in the saggital or coronal planes. The proximal-to-distal and medial-to-lateral dimensions of the tendon and the distance from the proximal tip of the olecranon to the proximal tendon insertion were measured microscopically on stained embedded sections. RESULTS: The proximal-to-distal dimension of the triceps tendon insertion was less than previously reported, whereas the medial-to-lateral dimension was similar. The true distance from the tip of the olecranon to the proximal tendon insertion was greater than the previously reported distance obtained via gross measurement. CONCLUSIONS: Gross measurement of the triceps tendon insertion overestimates and inaccurately represents the true insertional footprint. Gross measurement has been shown to demonstrate consistent disparity compared with histologic measurement. Histologic investigation provides a more accurate description. CLINICAL RELEVANCE: The finding that the distance from the articular tip of the olecranon to the proximal tendon insertion is greater than previously reported may have clinical implications. A triceps split approach may allow more visualization and exposure of the posterior joint and, therefore, lessen the need for triceps detachment or olecranon osteotomy.

Cathodic Voltage-controlled Electrical Stimulation Plus Prolonged Vancomycin Reduce Bacterial Burden of a Titanium Implant-associated Infection in a Rodent Model.

BACKGROUND: Cathodic voltage-controlled electrical stimulation (CVCES) of titanium implants, either alone or combined with a short course of vancomycin, has previously been shown to reduce the bone and implant bacterial burden in a rodent model of methicillin-resistant Staphylococcus aureus (MRSA) implant-associated infection (IAI). Clinically, the goal is to achieve complete eradication of the IAI; therefore, the rationale for the present study was to evaluate the antimicrobial effects of combining CVCES with prolonged antibiotic therapy with the goal of decreasing the colony-forming units (CFUs) to undetectable levels. QUESTIONS/PURPOSES: (1) In an animal MRSA IAI model, does combining CVCES with prolonged vancomycin therapy decrease bacteria burden on the implant and surrounding bone to undetectable levels? (2) When used with prolonged vancomycin therapy, are two CVCES treatments more effective than one? (3) What are the longer term histologic effects (inflammation and granulation tissue) of CVCES on the surrounding tissue? METHODS: Twenty adult male Long-Evans rats with surgically placed shoulder titanium implants were infected with a clinical strain of MRSA (NRS70). One week after infection, the rats were randomly divided into four groups of five: (1) VANCO: only vancomycin treatment (150 mg/kg, subcutaneous, twice daily for 5 weeks); (2) VANCO + 1STIM: vancomycin treatment (same as the VANCO group) coupled with one CVCES treatment (-1.8 V for 1 hour on postoperative day [POD] 7); (3) VANCO + 2STIM: vancomycin treatment (same as the VANCO group) coupled with two CVCES treatments (-1.8 V for 1 hour on POD 7 and POD 21); or (4) CONT: no treatment. On POD 42, the implant, bone, and peripheral blood were collected for CFU enumeration and histological analysis, where we compared CFU/mL on the implants and bone among the groups. A pathologist, blinded to the experimental conditions, performed a semiquantitative analysis of inflammation and granulation tissue present in serial sections of the humeral head for animals in each experimental group. RESULTS: The VANCO + 1STIM decreased the implant bacterial burden (median = 0, range = 0-10 CFU/mL) when compared with CONT (median = 5.7 × 10(4), range = 4.0 × 10(3)-8.0 × 10(5) CFU/mL; difference of medians = -5.6 × 10(4); p < 0.001) and VANCO (median = 4.9 × 10(3), range = 9.0 × 10(2)-2.1 × 10(4) CFU/mL; difference of medians = -4.9 × 10(3); p < 0.001). The VANCO + 1STIM decreased the bone bacterial burden (median = 0, range = 0-0 CFU/mL) when compared with CONT (median = 1.3 × 10(2), range = 0-9.4 × 10(2) CFU/mL; difference of medians = -1.3 × 10(2); p < 0.001) but was not different from VANCO (median = 0, range = 0-1.3 × 10(2) CFU/mL; difference of medians = 0; p = 0.210). The VANCO + 2STIM group had implant CFU (median = 0, range = 0-8.0 × 10(1) CFU/mL) and bone CFU (median = 0, range = 0-2.0 × 10(1) CFU/mL) that were not different from the VANCO + 1STIM treatment group implant CFU (median = 0, range = 0-10 CFU/mL; difference of medians = 0; p = 0.334) and bone CFU (median = 0, range = 0-0 CFU/mL; difference of medians = 0; p = 0.473). The histological analysis showed no deleterious effects on the surrounding tissue as a result of the treatments. CONCLUSIONS: Using CVCES in combination with prolonged vancomycin resulted in decreased MRSA bacterial burden, and it may be beneficial in treating biofilm-related implant infections. CLINICAL RELEVANCE: CVCES combined with clinically relevant lengths of vancomycin therapy may be a treatment option for IAI and allow for component retention in certain clinical scenarios. However, more animal research and human trials confirming the efficacy of this approach are needed before such a clinical recommendation could be made.

A biomechanical analysis of a single-row suture anchor fixation of a large bony bankart lesion.

PURPOSE: This study was conducted to assess whether a single-row suture anchor repair of a bony Bankart lesion comprising 19% of the glenoid length restores peak translational force and glenoid depth compared with the intact shoulder. METHODS: Nine thawed adult cadaveric shoulders were dissected and mounted in 45° of abduction and 30° of external rotation. A bony Bankart lesion was simulated with an anterior longitudinal osteotomy, parallel to the superoinferior axis of the glenoid, equivalent to 19% of the glenoid length. The humeral head was displaced 10 mm anteriorly at a speed of 2 mm/s with a 50-N compressive load applied. Testing was performed with the glenoid intact, a simulated lesion, and the lesion repaired with 3 single-row suture anchors. Median (interquartile range [IQR]) peak translational force and glenoid depth were reported. The Friedman test and post hoc comparisons with the Wilcoxon signed rank test were used for between-group analyses. RESULTS: Peak translational force decreased after osteotomy (13.7 N; IQR, 9.6 to 15.5 N; P = .01) and increased after the repair (18.3 N; IQR, 18.3 to 20.6 N; P = .01) compared with the intact shoulder (23.7 N; IQR, 16.4 to 29.9 N). Glenoid depth significantly decreased after the osteotomy (0.2 mm; IQR, -0.6 to 0.7 mm) compared with baseline (1.7 mm; IQR, 1.3 to 2.0 mm; P = .01) and increased after repair (0.8 mm; IQR, 0.1 to 1.0 mm; P = .03) compared with the osteotomized shoulder. The glenoid depth of the repair was less than the baseline value (P = .01). CONCLUSIONS: Repair of an anterior bony Bankart lesion equivalent to 19% of the glenoid length with 3 suture anchors restored the peak translational force needed to anteriorly displace the humerus relative to the glenoid; however, this technique failed to restore the natural glenoid depth in a laboratory setting. CLINICAL RELEVANCE: Our findings describe the inability of a single-row suture anchor repair to provide anatomic fixation of the bony Bankart lesion equivalent to 19% of the glenoid length.

Respiratory Adenovirus Quantification with a Droplet Digital Polymerase Chain Reaction (ddPCR) Assay.

Human adenoviruses (HAdVs) are double-stranded DNA viruses that can cause a wide spectrum of disease, including respiratory infections. Little is known about the value of respiratory HAdV quantification and its correlation with disease severity. In this study, we developed a quantitative HAdV droplet digital PCR (ddPCR) assay to study the association between viral loads, circulating types, and clinical outcomes. Remnant respiratory specimens positive for HAdV after the standard of care testing were collected from December 2020 to April 2022. A total of 129 samples were tested by a ddPCR method. Typing was performed using Nanopore sequencing of the hexon gene hypervariable region. Clinical chart reviews were performed to correlate the viral loads with the disease severity. The ddPCR assay showed an analytical sensitivity and a lower limit of quantification below 100 copies/mL. Of 129 positive clinical samples, 100 were quantified by ddPCR, 7 were too concentrated to be quantified, and 22 were negative. Of the 22 false negatives, only 3 were successfully typed; however, 99 of the 107 positive samples had a characterized genotype. The main HAdV types identified in this cohort were C1 (49.5%) followed by C2 (34.3%). No significant difference in HAdV loads was noted between patients who were admitted, those who required supplemental oxygen, and outpatients or between different HAdV types. HAdV ddPCR is a reliable absolute quantification approach for HAdV from respiratory samples. HAdV loads at initial presentation does not appear to differ between patients who require hospitalization versus outpatients. IMPORTANCE Measuring viral load using droplet digital PCR (ddPCR) is an absolute quantification approach that can facilitate comparability between different laboratories. This approach could prove valuable in studies that focus on the clinical utility of quantification. In this study, we evaluate a human adenovirus (HAdV) ddPCR assay and study the relationship between viral loads and outcomes after HAdV respiratory infections.

Participatory Media Literacy in Collaborative Video Annotation.

Collaborative Video Annotation (CVA) is a kludge where learners annotate video together, experiencing both the video and each other's annotations in a dynamic discussion. Three scenes from small group CVA discussions were selected for analysis from 14 CVA discussions where 8-12 learners interacted via the annotation tool on top of a video. The twenty-second scenes were analyzed for semiotic meaning-making practices and this revealed a variety of participatory media literacy levels among these undergraduates. Topics of discussions were related but not identical, and the selected exemplars showed a range of attention to communicative features of the media. Discussions evolved in dramatically different ways due to the interplay of images, text, and learner choices. Results suggest that converged media require new literacies educators would be wise to explore and wiser still to educate our learners about.

Energy absorbed by longitudinally splitting a tibialis anterior allograft: implications for double-bundle anterior cruciate ligament reconstruction.

PURPOSE: Split tibialis anterior (TA) allografts have been proposed as a source for double-bundle anterior cruciate ligament reconstruction. We sought to determine whether longitudinally splitting a TA tendon leads to a change in the mechanical properties of the tendon. METHODS: Seven cadaveric matched pairs of TA tendons were procured. One member of each pair was longitudinally pierced in its midportion and then bluntly split, creating 2 longitudinally divided grafts. The other member of the pair remained intact. Each tendon was then frozen into thermoelectrically cooled clamps and loaded to failure on an MTS machine (MTS Systems, Eden Prairie, MN) at a displacement of 1 mm/s. The area under the force-versus-displacement curve was calculated as an indicator of energy absorbed by the tendon before failure. The energy absorbed by the intact tendon was then compared with the summed energy absorbed by the 2 specimens obtained by splitting the sibling specimen. RESULTS: Energy absorbed by the intact tendon was 10,300 +/- 3,433 Nmm, whereas total energy absorbed by the 2 longitudinally split tendons was 10,530 +/- 2,095 Nmm (P = .78). CONCLUSIONS: Longitudinal splitting of a TA allograft by the technique described does not significantly affect the graft's ability to absorb energy. CLINICAL RELEVANCE: The splitting technique described can safely be used to create 2 grafts if surgeons wish to use a TA graft for a double-bundle anterior cruciate ligament reconstruction or for reconstruction by use of fixation devices requiring 2 looped tendon grafts.

Effects of hydroxyapatite on titanium foam as a bone ingrowth surface in acetabular shells: a canine study.

This study investigated a highly porous titanium foam with and without a PeriApetite coating as an alternative surface for implant fixation. Twelve mongrel canines received staged total hip replacements under International Animal Care and Use Committee (IACUC) approval from our institution. Animals were randomly placed in three- or six-month groups for sacrifice. Seventeen total hips were available for evaluation. The area and depth of ingrowth was measured by SEM. At three months, PeriApetite Ti foam had 37% more depth and almost 10% more bone ingrowth. Both groups were found not to be different at the six-month mark with over 36% of ingrowth calculated on SEM. The results prove not only that titanium foam is a viable ingrowth surface but also that PA coating can enhance the time to bony incorporation.

Comparing the analytical performance of three SARS-CoV-2 molecular diagnostic assays.

In December 2019, a novel coronavirus (SARS-CoV-2) was first isolated from Wuhan city, China and within three months, the global community was challenged with a devastating pandemic. The rapid spread of the virus challenged diagnostic laboratories to rapidly develop molecular diagnostic methods. As SARS CoV-2 assays became available for testing on existing molecular platforms, laboratories devoted unprecedented energy and resources into evaluating the analytical performance of the new tests and in some cases developed their own diagnostic assays under FDA-EUA guidance. This study compares the validation of three different molecular assays at the Johns Hopkins Molecular Virology laboratory: the RealStar® SARS-CoV-2 RT-PCR, ePlex® SARS-CoV-2, and the CDC COVID-19 RT-PCR tests. Overall, our studies indicate a comparable analytical performance of the three assays for the detection of SARS-CoV-2.

A prospective randomized trial of endoscopic versus conventional harvesting of the saphenous vein in coronary artery bypass surgery.

OBJECTIVES: Our objectives were (1) to determine whether minimally invasive endoscopic harvesting of the saphenous vein reduces morbidity due to postoperative wound infection and pain with improved cosmetic results and mobilization as compared with the conventional technique and (2) to compare the histologic properties of the saphenous veins harvested conventionally and endoscopically. METHODS: One hundred forty-four patients undergoing coronary artery bypass grafting were randomized to have vein harvesting performed by either the conventional (n = 72) or an endoscopic (n = 72) minimally invasive technique. RESULTS: Vein harvest time (open leg wound time) was significantly reduced in the endoscopic group (27.6 vs 64.4 minutes; P <.0001). The rate of leg wound infection was significantly reduced in the endoscopic group (4.3%) as compared with the conventional group (24.6%), a relative risk reduction of 83% (95% confidence interval: 36%-129%; P =.0006). The majority of infections (84.2%) occurred after hospital discharge. Postoperative leg pain, mobilization, and overall patient satisfaction were also significantly improved in the endoscopic group. Double blinded histologic assessment of harvested vein (n = 28) showed no evidence of any clinically important significant damage to the specimens in either group. CONCLUSIONS: In this prospective randomized trial, endoscopic harvesting of the saphenous vein significantly reduced postoperative leg wound complications, including infection, and improved patient satisfaction as compared with the conventional harvesting technique. There were no significant histologic differences between the conventional and endoscopically harvested saphenous veins.

Biomechanical comparison of femoral fixation devices for anterior cruciate ligament reconstruction using a novel testing method.

BACKGROUND: A novel biomechanical test method was implemented to compare the mechanical performance of two femoral fixation anchors (AperFix(r), Cayenne Medical, Scottsdale, AZ, USA or the AppianFx(r), KFx Medical, Carlsbad, CA, USA) that were utilized in anterior cruciate ligament reconstruction. METHODS: Anterior cruciate ligament reconstructions were performed in 20 porcine femurs by using bovine extensor tendon grafts secured with 9 mm femoral anchors (AperFix(r) or AppianFx(r)). 10 specimens were tested for each anchor type. Infrared position sensors determined the repair construct displacements during conditioning (20 cycles at 5-50 N at 0.25 Hz), cyclic loading (1500 cycles at 50-200 N at 1 Hz), and ultimate loading (150 mm/min). Outcomes included tendon elongation, anchor displacement, stiffness, maximum load, yield load, and load at 5mm of anchor displacement. It was hypothesized that there would be no differences in the outcomes of these two devices. Independent measure t-tests compared the performance of the devices (p<0.05). FINDINGS: The performance of the two anchors was comparable during the cyclic loading. During ultimate loading, a statistically higher yield load (p<0.01) and a load at 5mm of anchor displacement (p<0.01) were demonstrated for the AppianFx(r) as compared to AperFix(r). Maximum load and stiffness were not significantly different. INTERPRETATION: Given the good clinical track record of the AperFix(r), the comparable, and in some cases superior, the biomechanical data presented here for the AppianFx(r) are encouraging for their clinical implementation. This study also introduced a novel test method that directly tracks the relevant construct displacements during cyclic and ultimate loading tests of the anterior cruciate ligament reconstructions.

Ulnar coronoid process anatomy: possible implications for elbow instability.

Ulnar coronoid process fractures are relatively uncommon injuries usually occurring with elbow dislocations and contributing to elbow instability. Recent evidence suggests coronoid tip fractures have a role in the instability. We sought to quantify the capsular and brachialis attachments of the ulnar coronoid process to better understand why instability occurs. We prepared eight fresh-frozen cadaveric specimens to ascertain the specific attachment locations. After dissection, we isolated and resected the proximal ulna, including the coronoid process and its soft tissue attachments. We then embedded, sectioned, and stained the specimens. The average distance from the tip of the coronoid to the proximal capsule was 2.36 +/- 0.39 mm. The average distance from the tip of the coronoid to the proximal brachialis insertion was 10.13 +/- 1.6 mm. Most coronoid tip fractures included disruption of the anterior capsule, which potentially explains why instability can be associated with these fractures.

Isoxsuprine hydrochloride in the therapy of sickle cell leg ulceration

A double blind trial of isoxsuprine hydrochloride(Vasodilan) at the dose level of 40 mg b.d. has failed to show any effect on healing of leg ulcers or on certain haematological parameters in a 6-month trial in 40 patients with sickle cell disease (AU)