The physiological and disturbing effects of surgical face masks in the COVID-19 era.

BACKGROUND: In the COVID-19 pandemic, the concern about mask-harmful effects disturbed mask-adherence. However, it is not certain whether the masks cause cardiopulmonary overload. OBJECTIVE: To investigate the physiological and disturbing effects of surgical face masks during exercise. METHOD: The study was conducted in a tertiary hospital with 100 healthy volunteers between September 2020 and January 2021. Individuals with impaired walking, cardiopulmonary disease, and smoking were not included in the study. Initially, respiratory rate (RR), heart rate (HR), oxygen saturation (SpO2), end-tidal carbon dioxide (EtCO2) were measured.  Participants underwent 6-minute walking test (6MWT) with and without surgical masks.  Mask-discomfort questionnaire was applied before and after 6 MWT with the mask. RESULTS: Surgical masks during 6 MWTs significantly increased HR, RR, and EtCO2 levels (p<0.001).  Walking distance (p<0.001) and SpO2 level (p=0.002) were significantly decreased with mask. In Mask-Discomfort Questionnaire, humidity, temperature, resistance, salinity, odor, fatigue (p<0.001), and itching (p=0.001) scores significantly increased after 6MWT with mask. CONCLUSION: In healthy volunteers, HR, RR, EtCO2 were increased, and SpO2 and walking distance were decreased in the short-term, light exercise performed with the surgical mask. Findings support the concern that masks may cause cardiopulmonary overload (Tab. 3, Fig. 1, Ref. 17). Text in PDF www.elis.sk Keywords: COVID-19, masks, physiology, psychological side effects, questionnaire.

Evaluation of the course of the marginal mandibular branch of the facial nerve: a fresh cadaveric study.

The aim of this study was to determine the course of marginal mandibular nerve (MMN) in relation to the inferior border of the mandible from the gonion until its terminal insertion to the depressor anguli oris, relating the position to a palpable anatomical landmark with emphasis on the depth of the nerve in relation to platysma and the deep cervical fascia. Twelve fresh adult cadavers were dissected and the mandibular base was contoured using needles with 5mm gaps, starting from the mandibular angle to the muscular termination point of the nerve bilaterally. The distance between the MMN and the mandibular base and total length of the nerve was measured bilaterally. The highest levels of MMN were measured 6.9mm and 6.5mm above, and the lowest levels were measured 4mm and 3mm below the mandibular base on right and left sides, respectively. The mean (SD) total length of the nerve until the muscular termination point was calculated 33.57 (3.41) mm on the right and 33.51 (4.88) mm on the left side. Previous publications that we had read all fell short of defining the schematic pathway of the nerve, as the described landmarks were of a combination of bone and soft tissue, which are not always clinically reliable. We have overcome this difficulty by standardising the inferior border of the mandible as a point in order to trace the marginal mandibular branch pathway. It originates along the gonion and ends at the second premolar tooth area.

Uterus retrieval in cadaver: technical aspects.

The authors describe uterus retrieval in cadavers. Uterine retrieval with its vasculature could be successfully achieved in four of the presented cases. Special attention was given to dissection of bilateral ureters and hypogastric vasculature. Uterine retrieval with its vasculature and supporting sacrouterine,vesicouterine peritoneal folds is an anatomically feasible procedure in preparation for uterus transplantation.

Co-existence of the pectoralis quartus and pectoralis intermedius muscles.

During the routine dissection studies on the right side of a 56-year-old female cadaver we encountered co-existence of the pectoralis quartus and pectoralis intermedius muscles. The pectoralis quartus originated from the costochondral junction of the fifth and sixth ribs, and then extended laterally under the border of pectoralis major muscle, but it was entirely separate from it. The pectoralis quartus formed a long flat band with an average width of 1.5 cm. It then inserted as an aponeurosis to the both of lateral lip of the intertubercular groove of the humerus and tendon of the short head of the biceps brachii muscle. Furthermore, the pectoralis intermedius muscle was a fleshy slip between the pectoralis minor and pectoralis quartus muscles and arose from the third and fourth ribs. It then united to the tendon of the short head of the biceps brachii muscle two cm below the coracoid process.

Frequency-dependent transport through a quantum dot in the Kondo regime.

We study the ac conductance and equilibrium current fluctuations of a Coulomb-blockaded quantum dot in the Kondo regime. To this end we have developed an extension of the numerical renormalization group suitable for the nonperturbative calculation of finite-frequency transport properties. We demonstrate that ac transport gives access to the many-body resonance in the equilibrium spectral density. It provides a new route for measuring this key signature of Kondo physics, which so far has defied direct experimental observation.

Arterial, neural and muscular variations in the upper limb.

During our routine dissection studies we observed arterial, neural and muscular variations in the upper limbs of an adult male cadaver. In this case we observed the superficial brachial artery origination from the third part of the axillary artery, communications between the musculocutaneous and median nerves, variant formation of the brachial plexus, origination of the profunda brachii artery from the posterior circumflex humeral artery and supernumerary tendons of the abductor pollicis longus muscle. We think that such variations should be kept in mind during surgical and diagnostic procedures.

Kondo effect in the presence of itinerant-electron ferromagnetism studied with the numerical renormalization group method.

The Kondo effect in quantum dots (QDs)-artificial magnetic impurities-attached to ferromagnetic leads is studied with the numerical renormalization group method. It is shown that the QD level is spin split due to the presence of ferromagnetic electrodes, leading to a suppression of the Kondo effect. We find that the Kondo effect can be restored by compensating this splitting with a magnetic field. Although the resulting Kondo resonance then has an unusual spin asymmetry with a reduced Kondo temperature, the ground state is still a locally screened state, describable by Fermi liquid theory and a generalized Friedel sum rule, and transport at zero temperature is spin independent.

A variant of the Cannieu-Riche communication: case report.

A variant of Cannieu-Riche communication was encountered during the dissection studies. The communication was between the digital branch to the index finger and branch to the adductor pollicis muscle. Terminal communications between motor nerves may provide muscles with double motor innervation, and are important for the motor innervation of the hand, in particular the thenar muscles. This variant should be kept in mind during surgical operations, electrophysiological examinations of the hand.

A case with subclavius posticus muscle.

During routine dissection studies, we encountered an aberrant muscle in the neck region of a 50 year-old female cadaver. The accessory muscle was on the left side. It arose from the superior angle of the scapula and lay over the brachial plexus and brachial artery then inserted to the first rib's cartilage. According to its origin and insertion, the aberrant muscle was considered to be the subclavius posticus. The accessory muscle was innervated by a branch coming from the suprascapular nerve.

Anteroposterior diameter of the vertebral canal in cervical region: comparison of anatomical, computed tomographic, and plain film measurements.

The purpose was to compare the computed tomographic and plain film measurements with those of anatomical specimens to determine the antero-posterior diameter of the spinal canal in cervical region. Antero-posterior diameters of 75 cervical vertebral canals (15 sets of C3-C7) were measured anatomically at two different levels. Computed tomographic and plain film measurements were also obtained at the corresponding levels. Considering anatomical measurements as the gold standard, plain film and computed tomographic measurements were statistically compared. Interobserver and intraobserver differences were also evaluated. At the uppermost pedicle levels, there was no statistically significant difference between plain films and anatomical measurements, a good correlation. However, at lowermost pedicle level there was a statistically significant difference between plain films and anatomical measurements but not between tomographic and anatomical measurements. Our results suggest that plain films can accurately estimate cervical spinal canal mid-sagittal diameter at the uppermost pedicle level and be used as a first step examination for the evaluation of cervical spinal stenoses.

The canal of the posterior ampullar nerve: an important anatomic landmark in the posterior fossa transmeatal approach.

The canal of the posterior ampullar nerve is located between the inferior part of the internal acoustic meatus and ampulla of the posterior semicircular canal. It permits a more accurate localisation of the underlying labyrinth in inner-ear surgery. An anatomical and radiological study was undertaken to determine the importance the relationship between the canal and the labyrinth. Ten dry and 10 cadaveric temporal bone dissections, together with 20 high resolution CT scans of the same temporal bones were studied in an attempt to describe the anatomy of the canal of the posterior ampullar nerve. The length of the canal of the posterior ampullar nerve, the length of internal acoustic meatus, and distances from porus acusticus to the singular foramen and the transverse crest, and from the singular foramen to the vestibule and transverse crest, and from operculum to the sigmoid sinus and to the porus acusticus were measured. During the transmeatal posterior cranial fossa approach using the canal of the posterior ampullar nerve as a landmark enables more bone to be safely removed from the internal acoustic meatus thus preserving hearing.

The importance of the anatomy of the splenic artery and its branches in splenic artery embolisation.

Splenic artery embolisation can be performed preoperatively in an attempt to decrease thrombocyte destruction, or as an alternative to surgery, to obtain partial or total organ ablation. During this procedure, it is very important to deliver embolising agents distal to the origin to pancreatic branches to avoid the risk of pancreatitis. Therefore, a detailed knowledge of the anatomy of the splenic artery and its branches is required to achieve safe embolisation. The purpose of our study is to measure the average distance between the origin of the last pancreatic branch and the splenic hilum in digital angiograms and cadaver specimens.

[Pronounced bilateral mammary hypertrophy as a rare manifestation of acute lymphatic leukemia]. / Ausgeprägte bilaterale Mammahypertrophie als ungewöhnliche Manifestation einer akuten lymphatischen Leukämie.

A 33-year-old patient, hitherto healthy, has been admitted for clarification of bilateral mammary hypertrophy. In the course of the usual routine examination a lump of the size of a cherry was identified in the right breast. Within 6 weeks both breasts had become tight and grown symmetrically to three times their original size. A provisionary diagnosis of high malignant non-hodgkin lymphoma was made by multiple high speed needle biopsies and was later confirmed by a surgical tissue specimen of the right breast. For further classification a bone-marrow biopsy was taken from the pelvic bone and an immature acute lymphoblastic leukemia (ALL), known as preB1-ALL, diagnosed. Sonographic examination, computer tomography of the thorax and mammographical findings, as well as symptoms, outcome and differential diagnosis of a proliferative lymphatic disease with first manifestation in both breasts are presented and discussed.

Anatomical evaluation of the groove for the vertebral artery in the axis vertebrae for atlanto-axial transarticular screw fixation technique.

Anatomical measurements were studied on 40 dry axis vertebrae to determine the suitability of the groove for the vertebral artery for atlanto-axial transarticular screw fixation technique. We measured 13 parameters including three angular and 10 linear dimensions related to the groove of the vertebral artery, pedicle, and pars interarticularis and evaluated 80 measurements for each parameter. All measurements were done after placing a Kischner guide wire through the pedicle. We found that differences between measurements on the left and right sides of each vertebra were nonsignificant. In spite of the variability in measurements such as height, width, and median angle of the pedicle, the decline angle for instrumentation, the depth of the groove for the vertebral artery, and the internal height of the pars interarticularis, all of these had good symmetry. However, there were statistically significant differences between the sides in measurements for both the width (P=0.05) and the angle (P<0.02) of the pedicle allowing instrumentation and they did not show good symmetry. The risk of vertebral artery injury was found to be 22.5% per specimen, or 16.25% per screw inserted because the internal height of the pars interarticularis at point of fixation was

Tibial tubercle position and patellar height as indicators of malalignment in women with anterior knee pain.

In this study, we evaluated 70 limbs in 42 women with anterior knee pain. We investigated tibial tubercle position and patellar height indices as indicators of malalignment. Tibial tubercle rotation angles were determined by computed tomography, and patellar height indicators, Insall-Salvati, modified Insall-Salvati, Caton, and Blackburne indices were calculated on lateral knee roentgenograms. The results were compared to values obtained from 80 limbs in 40 healthy female volunteers. Tibial tubercle rotation angle was 68.1 degrees (+/-3.6) in the study group and 70.3 degrees (+/-3.8) in the control group. The difference was statistically significant (P< 0. 01). Patellar height indicators were not statistically different between the two groups. These results suggested that patellar height is not a malalignment indicator in female patients with anterior knee pain. These patients should be investigated by computed tomography to determine tibial tubercle position.

Percutaneous anterior odontoid screw fixation technique. A new instrument and a cadaveric study.

We describe a new instrument and a percutaneous technique for closed anterior fixation of odontoid fracture. The instrument which we developed consists of a telescopic tube system. This new instrument and closed fixation technique was used in six cadavers with type II odontoid fractures and to two cadavers with an intact odontoid process. Each cadaver underwent satisfactory placement of the screw to the odontoid with this technique under biplanar scopy control. After this procedure, no serious injury was found in the parapharyngeal and neurovascular areas of the necks of the cadavers, in which anatomical dissection along the track of this instrument was performed. The instrumentation and the technique as a whole is seen as reliably applicable for odontoid fracture fixation. Also, we expect to reduce operating time and hospital costs because this system is simple, easily applicable and minimally invasive.

An anomalous digastric muscle with three accessory bellies and one fibrous band.

During our routine dissection studies we encountered an anomalous digastric muscle with three accessory bellies and one fibrous band in one embedded cadaver. All of these structures were attached to the mylohyoid raphe. This anomaly should be considered during surgical procedures involving this region.

The effect of condylectomy on extreme lateral transcondylar approach to the anterior foramen magnum.

The dorsolateral, suboccipital, transcondylar technique was used in this cadaveric study. The angle and distance measurements in the corridors were taken intradurally both superior and inferior of the foramen magnum level. In the first stage of this study, the findings which were gained from the standard lateral suboccipital approach were compared with the findings after condyle and lateral atlantal mass removal. After condylectomy, the approach to anterior foramen magnum via both corridors was found to be shorter and the lateral angle of the exposure of the anterior foramen magnum was found to be wider. The considerable shortening of the distances to the anterior foramen magnum, especially in the superior corridor, emphasises the necessity of combining standard approaches with condylectomy. In addition, it was found that after condylectomy, considerable widening of both transverse and longitudinal planes in the inferior corridor allows the surgeon greater access to work on lesions. Furthermore, the freed space between the superior corridor and the interior corridor, which was gained by condylectomy, shows that condylectomy provides a combined approach to the inferior and superior parts of the foramen magnum anteriorly.

Peptide-binding macromolecules in the blood of seriously ill or mentally retarded patients.

This report describes macromolecules that bind (des-aspartic acid1)-angiotensin II, the des aspartic acid1 derivative of angiotensin I, and several biologically active and inactive analogues of these polypeptides. The macromolecules were found in the plasma of approximately 2 per cent of ambulatory adults and hospitalized children and 32 per cent of the patients at two institutions for the mentally retarded. The binding properties of these macromolecules were studied by incubating with peptides labeled with 125iodine, and separating bound from free labeled peptide using small gel filtration columns. The peptide-binding macromolecules from several patients were compared. They showed very similar specificity for a group of arginyl peptides of the des-aspartyl1-angiotensin sequence. The plasma binders differed from one another in their optimum pH and their mobility in electrophoretic fields. Those with more acid pH optima displayed more rapid electrophoretic mobility. The binders fell into two classes based on apparent molecular weight, approximately 140,000 and 250,000. Those with the higher apparent molecular weight contained a large proportion of binder that could be precipitated with antiserum to human IgA. Kinetic measurements showed that the plasma binders were somewhat heterogeneous with respect to affinity for (des-asp1)-angiotensin, with apparent association constants ranging from 10(7) to 10(8) M-1. Binding activity was labile to heat, and to treatment with pepsin or trypsin. It was inhibited by calcium, protamine, streptomycin, and some other cationic compounds. The plasma peptide binder differed in specificity and molecular weight from soluble angiotensin-binding molecules extracted from tissues, and from properties expected of a receptor for angiotensin. These macromolecules may be useful reagents for measuring (des-asp1)-angiotensins. Their presence in plasma samples may interfere with angiotensin assays in some circumstances.