The prevalence of double- and multiple crush syndromes in patients surgically treated for peripheral nerve compression in the upper limb.

OBJECTIVE: The double crush syndrome describes a condition characterized by multifocal entrapment of a nerve. In the upper limb, the high prevalence of carpal tunnel syndrome makes it a common diagnosis of assumption in the setting of median neuropathy. More proximal compressions may tend to be overlooked, under-diagnosed and under-treated in the population. This study aims to map the prevalence of peripheral upper limb nerve compressions among patients undergoing peripheral nerve decompression. METHODS: A prospective case series was conducted on 183 patients undergoing peripheral nerve decompression in a private hand surgery clinic. Level(s) of nerve compression in the median, ulnar and radial nerves were determined by history and physical examination. The prevalence of each nerve compression syndrome or combination of syndromes was analyzed. RESULTS: A total of 320 upper limbs in 183 patients were analyzed. A double crush of the median nerve at the levels of the lacertus fibrosus and carpal tunnel was identified in 78% of upper limbs with median neuropathy, whereas isolated lacertus syndrome and carpal tunnel syndrome were present in only 5% and 17% of affected limbs respectively. Cubital tunnel syndrome affected 12.5% of upper limbs, and 80% of these had concomitant lacertus and carpal tunnel syndromes, compared to only 7.5% with isolated cubital tunnel syndrome. CONCLUSION: A high prevalence should prompt clinicians towards more routine assessment for double crush syndrome to avoid misdiagnosis, inadequate treatment, recurrence, and revision surgeries.

Microbiota DNA isolation, 16S rRNA amplicon sequencing, and bioinformatic analysis for bacterial microbiome profiling of rodent fecal samples.

Fecal samples are frequently used to characterize bacterial populations of the gastrointestinal tract. A protocol is provided to profile gut bacterial populations using rodent fecal samples. We describe the optimal procedures for collecting rodent fecal samples, isolating genomic DNA, 16S rRNA gene V4 region sequencing, and bioinformatic analyses. This protocol includes detailed instructions and example outputs to ensure accurate, reproducible results and data visualization. Comprehensive troubleshooting and limitation sections address technical and statistical issues that may arise when profiling microbiota. For complete details on the use and execution of this protocol, please refer to Gubert et al. (2022).

Return to Play and Fracture Union After the Surgical Management of Jones Fractures in Athletes: A Systematic Review and Meta-analysis.

BACKGROUND: Proximal fifth metatarsal fractures are among the most common forefoot injuries in athletes. The management of this injury can be challenging because of delayed union and refractures. Intramedullary (IM) screw fixation rather than nonoperative management has been recommended in the athletic population. PURPOSE: To provide an updated summary of the return-to-play (RTP) rate and time to RTP after Jones fractures in athletes with regard to their management, whether operative or nonoperative, and to explore the union rate and time to union as well as the rate of complications such as refractures. STUDY DESIGN: Meta-analysis. METHODS: Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, 2 independent team members searched several databases including PubMed, MEDLINE, Embase, Google Scholar, Web of Science, Cochrane Library, and ClinicalTrials.gov through November 2019 to identify studies reporting on Jones fractures of the fifth metatarsal exclusively in athletes. The primary outcomes were the RTP rate and time to RTP, whereas the secondary outcomes were the number of games missed, time to union, and union rate as well as the rates of nonunion, delayed union, and refractures. RESULTS: Of 168 studies identified, 22 studies were eligible for meta-analysis with a total of 646 Jones fractures. The overall RTP rate was 98.4% (95% CI, 97.3%-99.4%) in 626 of 646 Jones fractures. The RTP rate with IM screw fixation only was 98.8% (95% CI, 97.8%-99.7%), with other surgical fixation methods (plate, Minifix) was 98.4% (95% CI, 95.8%-100.0%), and with nonoperative management was 71.6% (95% CI, 45.6%-97.6%). There were 3 studies directly comparing RTP rates with surgical versus nonoperative management, which showed significant superiority in favor of surgery (odds ratio, 0.033 [95% CI, 0.005-0.215]; P < .001). The RTP rate according to type of sport was 99.0% (95% CI, 97.5%-100.0%) in football, 91.1% (95% CI, 82.2%-99.4%) in basketball, and 96.6% (95% CI, 92.6%-100.0%) in soccer. The overall time to RTP was 9.6 weeks (95% CI, 8.5-10.7 weeks). The time to RTP in the surgical group (IM screw fixation) was 9.6 weeks (95% CI, 8.3-10.9 weeks), which was significantly less than that in the nonoperative group of 13.1 weeks (95% CI, 8.2-18.0 weeks). The pooled union rate in the operative group (excluding refractures) was 97.3% (95% CI, 95.1%-99.4%), whereas the pooled union rate in the nonoperative group was 71.4% (95% CI, 49.1%-93.7%). The overall time to union was 9.1 weeks (95% CI, 7.7-10.4 weeks). The time to union with IM screw fixation (8.2 weeks [95% CI, 7.5-9.0 weeks]) was shorter than that with nonoperative treatment (13.7 weeks [95% CI, 12.7-14.6 weeks]). The rate of delayed union was 2.5% (95% CI, 1.2%-3.7%), and the overall refracture rate was 10.2% (95% CI, 5.9%-14.5%). CONCLUSION: The RTP rate and time to RTP after the surgical management of Jones fractures in athletes were excellent, regardless of the implant used and type of sport. IM screw fixation was superior to nonoperative management, as it led to a higher rate of RTP, shorter time to RTP, higher rate of union, shorter time to union, and improved functional outcomes. We recommend surgical fixation for all Jones fractures in athletes.

Identification of a thalidomide derivative that selectively targets tumorigenic liver progenitor cells and comparing its effects with lenalidomide and sorafenib.

BACKGROUND & AIMS: The availability of non-tumorigenic and tumorigenic liver progenitor cell (LPC) lines affords a method to screen putative anti-liver cancer agents to identify those that are selectively effective. To prove this principle we tested thalidomide and a range of its derivatives and compared them to lenalidomide and sorafenib, to assess their growth-inhibitory effects. METHODS: Cell growth, the mitotic and apoptotic index of cell cultures were measured using the Cellavista instrument (SynenTec) using commercially available reagents. RESULTS: Neither lenalidomide nor thalidomide (100 µM) affected tumorigenic LPCs but killed their non-tumorigenic counterparts. Sorafenib arrested growth in both cell types. All but two derivatives of thalidomide were ineffective; of the two effective derivatives, one (thalidomide C1) specifically affected the tumorigenic cell line (10 µM). Mitotic and apoptotic analyses revealed that thalidomide C1 induced apoptotic cell death and not mitotic arrest. CONCLUSIONS: This study shows that screens incorporating non-tumorigenic and tumorigenic liver cell lines are a sound approach to identify agents that are effective and selective. A high throughput instrument such as the Cellavista affords robust and reproducible objective measurements with a large number of replicates that are reliable. These experiments show that neither lenalidomide nor thalidomide are potentially useful for anti-liver cancer therapy as they kill non-tumorigenic liver cells and not their tumorigenic counterparts. Sorafenib in contrast, is highly effective, but not selective. One tested thalidomide derivative has potential as an anti-tumor drug since it induced growth arrest; and importantly, it selectively induced apoptotic cell death only in tumorigenic liver progenitor cells.

iPSC-derived human mesenchymal stem cells improve myocardial strain of infarcted myocardium.

We investigated global and regional effects of myocardial transplantation of human induced pluripotent stem cell (iPSC)-derived mesenchymal stem cells (iMSCs) in infarcted myocardium. Acute myocardial infarction (MI) was induced by ligation of left coronary artery of severe combined immunodeficient mice before 2 × 10(5) iMSCs or cell-free saline were injected into peri-infarcted anterior free wall. Sham-operated animals received no injection. Global and regional myocardial function was assessed serially at 1-week and 8-week by segmental strain analysis by using two dimensional (2D) speckle tracking echocardiography. Early myocardial remodelling was observed at 1-week and persisted to 8-week with global contractility of ejection fraction and fractional area change in saline- (32.96 ± 14.23%; 21.50 ± 10.07%) and iMSC-injected (32.95 ± 10.31%; 21.00 ± 7.11%) groups significantly depressed as compared to sham control (51.17 ± 11.69%, P < 0.05; 34.86 ± 9.82%, P < 0.05). However, myocardial dilatation was observed in saline-injected animals (4.40 ± 0.62 mm, P < 0.05), but not iMSCs (4.29 ± 0.57 mm), when compared to sham control (3.74 ± 0.32 mm). Furthermore, strain analysis showed significant improved basal anterior wall strain (28.86 ± 8.16%, P < 0.05) in the iMSC group, but not saline-injected (15.81 ± 13.92%), when compared to sham control (22.18 ± 4.13%). This was corroborated by multi-segments deterioration of radial strain only in saline-injected (21.50 ± 5.31%, P < 0.05), but not iMSC (25.67 ± 12.53%), when compared to sham control (34.88 ± 5.77%). Improvements of the myocardial strain coincided with the presence of interconnecting telocytes in interstitial space of the infarcted anterior segment of the heart. Our results show that localized injection of iMSCs alleviates ventricular remodelling, sustains global and regional myocardial strain by paracrine-driven effect on neoangiogenesis and myocardial deformation/compliance via parenchymal and interstitial cell interactions in the infarcted myocardium.

Hydrogen sulfide augments the proliferation and survival of human induced pluripotent stem cell-derived mesenchymal stromal cells through inhibition of BKCa.

BACKGROUND: Hydrogen sulfide (H2S) is an endogenously generated gaseous transmitter known for its cytoprotective effect mediated by the PI3K-Akt signaling pathway. Human induced pluripotent stem cell (hiPSC)-derived mesenchymal stromal cells (MSCs), or hiPSC-MSCs, represent an alternative source of MSCs for autologous cell therapy. The big-conductance Ca(2+)-activated outward K(+) currents (BKCa), known to mediate cell proliferation, have been detected in >80% of hiPSC-MSCs. The present study aimed to explore the effect of H2S on survival and proliferation of hiPSC-MSCs and investigate the mediatory role of BKCa. METHODS: Effects of H2S on proliferation and survival of hiPSC-MSCs were measured by 5-bromo-2-deoxyuridine incorporation, population doubling and cell cycle assays, and by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide assay and 4'-6-diamidino-2-phenylindole staining, respectively. BKCa was recorded by means of the whole-cell patch-clamp technique. The expressions of KCa 1.1 (encoding BKCa) and apoptosis-related genes were measured by reverse transcriptase-polymerase chain reaction. The phosphorylation of Akt was assessed by Western blot analysis. RESULTS: Exogenously administered NaHS (an H2S donor, 50-300 µmol/L) significantly promoted proliferation of hiPSC-MSCs. NaHS prevented the hypoxia-induced apoptosis and suppressed BKCa currents without altering the expression levels of α- and ß-KCa 1.1. In addition, NaHS increased the phosphorylation of Akt and decreased the expression of Caspase 8 and Bax in hiPSC-MSCs. Paxilline (1 µmol/L), a BKCa blocker, showed similar effects on promoting cell proliferation and phosphorylation of Akt and suppression of apoptotic genes in hiPSC-MSCs. CONCLUSIONS: Our data confirmed that H2S arguments the proliferation and survival of hiPSC-MSCs through activation of the PI3K-Akt pathway and that such effects could be mediated through inhibition of BKCa.

One-step derivation of cardiomyocytes and mesenchymal stem cells from human pluripotent stem cells.

Cardiomyocytes (CMs) and mesenchymal stem cells (MSCs) are important cell types for cardiac repair post myocardial infarction. Here we proved that both CMs and MSCs can be simultaneously generated from human induced pluripotent stem cells (hiPSCs) via a pro-mesoderm differentiation strategy. Two hiPSC lines, hiPSC (1) and hiPSC (2) were generated from human dermal fibroblasts using OCT-4, SOX-2, KLF-4, c-Myc via retroviral-based reprogramming. H9 human embryonic stem cells (hESCs) served as control. CMs and MSCs were co-generated from hiPSCs and hESCs via embryoid body-dependent cardiac differentiation protocol involving a serum-free and insulin-depleted medium containing a p38 MAPK inhibitor, SB 203580. Comparing to bone marrow and umbilical cord blood-derived MSCs, hiPSC-derived MSCs (iMSCs) expressed common MSC markers and were capable of adipogenesis, osteogenesis and chondrogenesis. Moreover, iMSCs continuously proliferated for more than 32 population doublings without cellular senescence and showed superior pro-angiogenic and wound healing properties. In summary, we generated a large number of homogenous MSCs in conjunction with CMs in a low-cost and efficient one step manner. Functionally competent CMs and MSCs co-generated from hiPSCs may be useful for autologous cardiac repair.