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Journal of Neuroengineering and... Mar 2023Contractions of muscles in the calf induced by neuromuscular electrical stimulation (NMES) may prevent venous thromboembolism, help rehabilitation and optimize strength...
BACKGROUND
Contractions of muscles in the calf induced by neuromuscular electrical stimulation (NMES) may prevent venous thromboembolism, help rehabilitation and optimize strength training, among other uses. However, compliance to NMES-treatment is limited by the use of suboptimal stimulation points which may cause discomfort and less effectivity. Knowledge of where one is most likely to find muscle motor points (MP) could improve NMES comfort and compliance.
AIMS
To anatomically map the MPs of the calf as well as to calculate the probability of finding a MP in different areas of the calf.
MATERIAL AND METHODS
On 30 healthy participants (mean age 37 years) anatomical landmarks on the lower limbs were defined. The location of the four most responsive MPs on respectively the medial and lateral head of gastrocnemius were determined in relation to these anatomical landmarks using a MP search pen and a pre-set MP search program with 3 Hz continuous stimulation (Search range:4.0-17.5 mA). The anatomy of the calves was normalized and subdivided into a matrix of 48 (6 × 8) smaller areas (3 × 3 cm), from upper medial to lower lateral, in order to calculate the probability of finding a MP in one of these areas. The probability of finding a MP was then calculated for each area and presented with a 95% confidence interval.
RESULTS
The MP heatmap displayed a higher concentration of MPs proximally and centrally on the calf. However, there were wide inter-individual differences in the location of the MPs. The highest probability of finding a MP was in area 4, located centrally and medially, and in area 29, located centrolaterally and around the maximum circumference, both with 50% probability (95% CI: 0.31-0.69). The second highest probability of finding MPs was in areas 9, 10, 16, proximally and medially, all with 47% probability (95% CI: 0.28-0.66). These areas 4, 9, 10, 16 and 29 exhibited significantly higher probability of finding motor points than all areas with a mean probability of 27% and lower (p < 0.05) The lateral and distal outskirts exhibited almost zero probability of finding MPs.
CONCLUSIONS
This MP heatmap of the calf could be used to expedite electrode placement and to improve compliance in order to receive consistent and enhanced results of NMES treatments.
Topics: Animals; Cattle; Humans; Adult; Muscles; Lower Extremity; Electrodes; Healthy Volunteers; Individuality
PubMed: 36859293
DOI: 10.1186/s12984-023-01152-5 -
The Journal of Invasive Cardiology Feb 2022During an optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) of a calcified left anterior descending artery (LAD), the distal tip of the...
During an optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) of a calcified left anterior descending artery (LAD), the distal tip of the OCT catheter got stuck, and forceful tugging on the catheter by the operator led to LAD stent deformation proximally across the overlap between the proximal and middle stents. The purpose of these images is to make the readers aware of the very real and serious risk of a stuck OCT catheter, especially while imaging distal coronary arteries and overlapping stents. Increasing the length of the over-the-wire segment and hydrophilic coating of the OCT catheter may also be explored with manufacturers to prevent this complication.
Topics: Catheters; Coronary Angiography; Coronary Artery Disease; Coronary Vessels; Humans; Percutaneous Coronary Intervention; Stents; Tomography, Optical Coherence; Treatment Outcome; Ultrasonography, Interventional
PubMed: 35100558
DOI: No ID Found -
Cureus Mar 2020Introduction The aim of our study was to describe the injury pattern and outcomes of active-duty subjects that underwent humeral external fixation and to determine if...
Introduction The aim of our study was to describe the injury pattern and outcomes of active-duty subjects that underwent humeral external fixation and to determine if the placement of external fixator pins outside of the radial nerve safe zones is correlated with injury to the radial nerve. Materials and methods We examined all US Service members treated with humeral external fixation at our facility from June 2005 through June 2015. The mechanism of injury, injury pattern, location of external fixation application, pre- and postoperative radial nerve function, presence or absence of radial nerve transection from injury or external fixation, anatomic location of pins in relation to the radial nerve safe zone, and final radial nerve outcomes were recorded. We defined the proximal safe zone as 5 cm distal to the acromion to 14.8 cm proximal to the lateral epicondyle, and we defined the distal safe zone as the proximal 70% of the transepicondylar width of the humerus when projected proximally from the lateral epicondyle. Results For our study, 123 patients were identified over our date range, and 16 subjects were included with documentation regarding nerve function/injury characteristics, appropriate radiographs, and active duty status. Around 80% of injuries resulted from a blast mechanism, and 80% of injury patterns included either an intraarticular or open fracture. The radial nerve safe zone was violated in 15 of the 16 subjects (94%). The one subject with a safe construct did not sustain a nerve injury. Complete preoperative documentation on nerve function was only available for half of the subjects. Two of five subjects known to have intact function prior to external fixation had a postoperative neurologic deficit (40%). Of eight subjects with unknown radial nerve function prior to external fixation, seven subjects had full nerve function at the final follow up, and one subject had partial sensory function only. Of the three subjects with impaired preoperative radial nerve function, two made a full recovery, and the third recovered sensory function only. Around 50% of all subjects required medical retirement. Conclusion External fixation of upper extremity injuries in combat is rarely absolutely indicated, often results in the placement of pins outside of the radial nerve safe zone, and is associated with up to a 40% incidence of radial nerve injury.
PubMed: 32351815
DOI: 10.7759/cureus.7435 -
Cellular and Molecular Life Sciences :... Jul 2021Cyclin-dependent kinase 9 (CDK9), the kinase component of positive transcription elongation factor b (P-TEFb), is essential for transcription of most protein-coding... (Review)
Review
Cyclin-dependent kinase 9 (CDK9), the kinase component of positive transcription elongation factor b (P-TEFb), is essential for transcription of most protein-coding genes by RNA polymerase II (RNAPII). By releasing promoter-proximally paused RNAPII into gene bodies, CDK9 controls the entry of RNAPII into productive elongation and is, therefore, critical for efficient synthesis of full-length messenger (m)RNAs. In recent years, new players involved in P-TEFb-dependent processes have been identified and an important function of CDK9 in coordinating elongation with transcription initiation and termination has been unveiled. As the regulatory functions of CDK9 in gene expression continue to expand, a number of human pathologies, including cancers, have been associated with aberrant CDK9 activity, underscoring the need to properly regulate CDK9. Here, I provide an overview of CDK9 function and regulation, with an emphasis on CDK9 dysregulation in human diseases.
Topics: Animals; Cyclin-Dependent Kinase 9; Cyclin-Dependent Kinases; Humans; Phosphorylation; RNA Polymerase II; Transcription, Genetic
PubMed: 34146121
DOI: 10.1007/s00018-021-03878-8 -
Clinics in Colon and Rectal Surgery Jan 2023Many surgeons tend to overuse proximal fecal diversion in the setting of colonic surgery. The decision to proximally divert an anastomosis should be made with careful... (Review)
Review
Many surgeons tend to overuse proximal fecal diversion in the setting of colonic surgery. The decision to proximally divert an anastomosis should be made with careful consideration of the risks and benefits of proximal diversion. Proximal diversion does not decrease the rate of anastomotic leak, but it does decrease the severity of leaks. Anastomotic height for low pelvic anastomoses, hemodynamic instability, steroid use, male sex, obesity, malnutrition, smoking, and alcohol abuse increase the rate of anastomotic leak. Biologics, most immunosuppressive agents, unprepped colons, and radiation for rectal cancer do not contribute to increased rates of anastomotic leak. Proximal fecal diversion creates additional potential morbidity, higher rates of readmission, and need for a subsequent hospitalization and operation for reversal. Additionally, diverted patients have higher rates of anastomotic stricture and delayed recognition of chronic leaks. These downsides to diversion must be weighed with a patient's perceived ability to handle the physiologic stress and consequences of a severe leak if reoperation is required. When trying to determine which patients can handle a leak, the modified frailty index can help to objectively determine a patient's risk for increased rate of morbidity and failure to rescue in the event of a leak. While proximal diversion is still warranted in many cases, we find that certain clinical scenarios often lead to overuse of proximal diversion. The old surgical adage "If you are considering diverting, you should probably do it" should be tempered by an understanding of the risk and benefits of diversion.
PubMed: 36619277
DOI: 10.1055/s-0042-1757559 -
Updates in Surgery Feb 2023Classification of adenocarcinomas (AC) arising around or within the gastroesophageal junction (GEJ) is hampered by major morphologic and phenotypic overlaps. We reviewed... (Review)
Review
Classification of adenocarcinomas (AC) arising around or within the gastroesophageal junction (GEJ) is hampered by major morphologic and phenotypic overlaps. We reviewed the surgical pathology of esophagectomy specimens of 115 primary resected AC of the esophagus as defined by the 5th edition of the WHO classification regarding the anatomical site of the tumor, with corresponding categorization according to the Siewert AEG Classification and the preceding 4th edition of the WHO (discriminating esophageal adenocarcinomas/EAC and adenocarcinomas of the gastroesophageal junction/AdGEJ), and further histology findings. In addition, immunohistochemistry (IHC) for CDX2, CK7, CK20, MUC2, MUC5AC and MUC6 was performed. Sixty-eight cases were Siewert AEG type I and 47 cases Siewert AEG type II. Out of the AEG I tumors, 26 were classified as AdGEJ. Regardless of the classification system, more proximally located tumors showed less aggressive behavior with lower rates of lymph node metastases, lymphatic, venous and perineural invasion, better histological differentiation (p < 0.05 each) and were more frequently associated with pre-neoplastic Barrett's mucosa (p < 0.001). Histologically, the tumors displayed intestinal morphology in the majority of cases. IHC showed non-conclusive patterns with a frequent CK7+/CK20+ immunophenotype in all tumors, but also a gastric MUC5AC+ and MUC6+ phenotype in some proximal tumors. In conclusion, histology of the tumors and IHC failed to distinguish reliably between more proximal and more distal tumors. The presence of Barrett's mucosa rather than location alone, however, may help to further differentiating adenocarcinomas arising in this region and may be indicative for a particular biologic type.
Topics: Humans; Barrett Esophagus; Pathology, Surgical; Stomach Neoplasms; Esophageal Neoplasms; Esophagogastric Junction; Adenocarcinoma
PubMed: 36001283
DOI: 10.1007/s13304-022-01360-z -
Blood Jun 2022Approximately a third of patients with paroxysmal nocturnal hemoglobinuria (PNH) remain transfusion dependent or have symptomatic anemia despite treatment with a C5...
Approximately a third of patients with paroxysmal nocturnal hemoglobinuria (PNH) remain transfusion dependent or have symptomatic anemia despite treatment with a C5 inhibitor. Pegcetacoplan inhibits complement proximally at the level of C3 and is highly effective in treating persistent anemia resulting from C3-mediated extravascular hemolysis. We describe the rationale for C3 inhibition in the treatment of PNH and discuss preclinical and clinical studies using pegcetacoplan and other compstatin derivatives. We propose an approach for sequencing complement inhibitors in PNH.
Topics: Antibodies, Monoclonal, Humanized; Complement C3; Erythrocytes; Hemoglobinuria, Paroxysmal; Hemolysis; Humans; Peptides, Cyclic
PubMed: 35349667
DOI: 10.1182/blood.2021014868