Δευτέρα 29 Ιουλίου 2019

Chondroepitrochlearis and a supernumerary head of the biceps brachii

Abstract

Unique variants of the pectoralis major and biceps brachii were found during a routine student dissection of a 96-year-old Caucasian female’s axilla and brachium. The donor cadaver had bilateral presentation of a muscle originating from the pectoralis major, near the lateral lip of the intertubercular groove, extending obliquely to insert on the medial intermuscular septum and medial epicondyle of the humerus. This muscle variant is currently described as a rare presentation of the chondroepitrochlearis, potentially a remnant of the panniculus carnosus in man. Often considered to be a thin, slender muscle taking origin from the true ribs, the right-side chondroepitrochlearis described in this report was notably larger—to the authors’ knowledge—than all other published cases, measuring 38.1 mm at the widest point. Meanwhile, another small muscle originating on the posterior surface of the pectoralis major tendon was present. Due to its insertion, the muscle was identified as a supernumerary portion, or a third head, of the biceps brachii. The proximal attachment of both the chondroepitrochlearis and the third head of the biceps brachii could impose functional limitations on the pectoralis major.

Histological and biochemical changes induced by gibberellic acid in the livers of pregnant albino rats and their offspring: ameliorative effect of Nigella sativa

Abstract

Gibberellic acid (GA3), a plant growth regulator, is widely used in agriculture in many countries to accelerate the growth of fruits and vegetables. We designed histological, immunohistochemical, and biochemical studies to evaluate the deleterious effects of GA3 on the livers of adult pregnant rats and their offspring and to assess the possible ameliorative effect of Nigella sativa Linn. (NsL.oil) against these effects. Twenty-four pregnant albino rats were utilized, randomly divided into four groups: The first group was used as a negative control group, while the second group (positive control group) was provided NsL.oil at a dose of 100 mg/kg of bodyweight. Animals in the third group (GA3 group) were provided 200 ppm of GA3 dissolved in distilled water from the 7th day of pregnancy until 1 day after delivery. Animals in the last group (GA3 + NsL.oil group) were provided GA3 and NsL-oil at the same doses as mentioned above. One day after delivery, each group of lactating mothers and their pups were sacrificed. Liver specimens were subjected to histopathological, immunohistochemical, and biochemical examinations. The livers of rats from the GA3 group showed various degenerative changes, being predominant in the livers of the mothers compared with the offspring. The pathological changes in the livers of the offspring suggested transplacental passage of GA3. The results reveal that GA3 ingestion induced a significant increase in alanine aminotransferase (ALT) and aspartate transaminase (AST) activities in the serum of both groups of mothers and their pups, with a significant increment in lipid peroxidation as evidenced by enhanced malondialdehyde (MDA) levels with significant decrements in superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) enzymatic activities in comparison with control groups in the liver of mothers and their offspring. Histopathological examination showed hydropic degeneration and inflammatory cellular infiltration. Additionally, there was fibrosis around the portal area. Moreover, immunolocalization revealed downregulation of the expression of the antiapoptotic marker Bcl-2 in hepatocytes and upregulation of the expression of the apoptotic marker Bax in the treated group. Concomitant use of NsL.oil along with GA3 exerted a considerable reversing effect on histopathological and biochemical changes in the livers of mother groups and their pups. The results of the present study highlight the consequences of exposure to GA3 during pregnancy on hepatic tissue in both mothers and their offspring. Furthermore, the study suggests use of NsL.oil as a potential protective strategy against GA3-induced liver toxicity.

The natural plant flavonoid apigenin is a strong antioxidant that effectively delays peripheral neurodegenerative processes

Abstract

Oxidative stress contributes to the progression of neurodegenerative diseases of the central and peripheral nervous systems, including Alzheimer’s disease, Parkinson’s disease, stroke, and diabetic neuropathy. Despite the greater capability of peripheral nerves to regenerate compared with those in the brain or spinal cord, chronic oxidative stress leads to irreversible neurodegeneration in peripheral nerves. Thus, many efforts have been made to defend against irreversible peripheral nerve degeneration and oxidative stress. Numerous phytochemicals have been revealed as antioxidants which neutralize free radicals and reduce peripheral neurocellular damage. Among them, polyphenols alleviate neurodegeneration by interacting with reactive oxygen species. Apigenin is a polyphenol found in plant-derived foods, including parsley, thyme, celery, and chamomile tea. Apigenin has been reported to exert antioxidative effects by scavenging free radicals. In particular, apigenin has a neuroprotective effect against oxidative stress in neurological disorders, such as cerebral ischemia. However, to date, no studies have shown an association of the inhibitory effect of apigenin with peripheral nerve degeneration. In this work, we showed that apigenin has a neuroprotective effect against peripheral nerve degeneration according to four key phenotypes: axonal degradation, myelin fragmentation, trans-dedifferentiation, and proliferation of Schwann cells via Krox20- and extracellular signal-regulated kinase-independent processes. Thus, apigenin could be a good candidate to treat peripheral neurodegenerative diseases.

Checking the shape and lobation of the right atrial appendage in view of their clinical relevance

Abstract

Clinically, anatomy of the appendage of the atrium is associated with atrial fibrillation, with the shape and lobation of the appendage having been used to stratify the risk of thromboembolic events. The aim of this study was to examine the age-dependent change in the shape and lobation of the right atrial appendage. A cross-sectional evaluation of the heart of 172 adults and 61 children, fixed in 4% formalin solution was performed. The morphology of the atrial appendage was assessed based on its shape and number of lobes. The following shapes of the appendage were identified: horse head, parrot beak, anvil, sailboat, and undefined. Using the horse head shape as a reference, the risk for a thromboembolic event was higher for anvil, sailboat and undefined shapes of the appendage (p < 0.001). The number of lobes ranged between 1 and 6 in adults, and 1 and 5 in children. The number of lobes for each shape was equivalent between adults and children (p > 0.05). Our analysis indicated that the number of lobes and the distribution of shapes of the atrial appendage remained unchanged throughout life. The risk for a thromboembolic event increased with the morphological complexity of the appendage (anvil, sailboat, and undefined), with 21% of adult hearts being prone to intra-atrial thrombosis in cases of fibrillation.

Two mammalian species in which the intercostal nerves innervate the serratus anterior or scalenus muscles together with the cervical nerves: an important clue to clarify the homology of cervico-thoracic trunk muscles in mammals

Abstract

The levator scapulae, rhomboideus, and serratus anterior muscles (as a group referred to the dorsal shoulder girdle muscles) and the scalenus muscles in mammals are usually innervated by cervical nerves. However, in koalas, the serratus anterior is additionally innervated by the lateral cutaneous branch of the first intercostal nerve. In cats, as in some other mammalian species, a part of the scalenus muscle (scalenus longus muscle) is innervated by the lateral cutaneous branches of the intercostal nerves. A precise comparison of the innervating nerves at the same segment in these two cases could clarify the homological relationship between the cervical and thoracic trunk muscles. In this context, the aim of this study was to follow the nerve fibers included in the nerves supplying the dorsal shoulder girdle and scalenus muscles up to the level of the spinal nerve roots in two koalas and two cats. The resultant observations revealed that both of the nerves to the serratus anterior in koalas and to the scalenus muscles in cats from the lateral cutaneous branch of the intercostal nerve occupy the same position in the spinal roots as the cervical nerve branches to the dorsal shoulder girdle muscles and the thoracic nerve branches to the external intercostal muscle. Based on these results, the axial trunk muscles in the cervico-thoracic region could be classified as follows: the scalenus and dorsal shoulder girdle muscles belong to the same lateral axial trunk muscle group as the external intercostal muscle, and are clearly distinguished from the medial group, such as the internal and innermost intercostal muscle.

Incidence of vertebral artery of aortic arch origin, its level of entry into transverse foramen, length, diameter and clinical significance

Abstract

The aim of this study was to show the incidence of vertebral artery of aortic arch origin, its level of entry into transverse foramen, including extra- and intracranial morphometry, and clinical significance. A total of 266 embalmed cadavers were studied. We found 14 left vertebral arteries (5.3%) emerging from aortic arch. Most of the left vertebral arteries of aortic arch origin (78.6%) entered the fifth cervical transverse foramina, whereas most of the vertebral arteries of subclavian origin (94.7% left and 99.2% right) entered the sixth cervical transverse foramina. Their average prevertebral length was 8.24 ± 1.09 cm ,which was about twice as long as the right vertebral artery (3.88 ± 1.14 cm). The average outer diameters of the prevertebral part and ensuing intracranial part of the left vertebral artery of aortic arch origin were 4.36 ± 0.93 and 3.62 ± 0.62 mm, respectively. The mean corresponding diameters of the vertebral artery of subclavian origin were 5.06 ± 1.04 and 3.87 ± 0.83 mm, respectively. All of the vertebral arteries decreased significantly in size after entering the cranial cavity. The reduction in caliber of the intracranial part of the vertebral artery compared with the prevertebral part of its own vessel has never been reported elsewhere. Knowledge of such anatomical variations is important in interpreting CT angiography, anterior cervical decompression and aortic arch surgery to prevent iatrogenic injury of the vertebral artery.

Influence of phase of respiration on thoracic conformation at multiple vertebral levels in German shepherd dog

Abstract

This study aimed to objectively assess the influence of phase of respiration on thoracic conformation at different vertebral levels. An observational prospective study was done on 30 German shepherd dogs. Thoracic radiographs were obtained at peak inspiration and expiration; thoracic depth and width were measured at each vertebral level. The change in thoracic dimensions, and the frontosagittal and vertebral indices were calculated at each level. The level of the 10th thoracic segment was the deepest and widest level of the thorax. At the first three thoracic segments, the percentage change of thoracic depth ranged from 3.2 ± 3.0 to 5.1 ± 3.9 % and 4.2 ± 2.8 to 6.6 ± 4.9 % for thoracic width. At the 4th–9th thoracic segments, this change increased to 13.3 ± 5.0 to 19.3 ± 3.8 % in thoracic depth and 13.9 ± 6.2 to 18.8 ± 8.2 % in thoracic width. The percentage change in thoracic width was significantly greater than thoracic depth at the level of the 6th and 7th thoracic segments (P = 0.027, 0.019). Phase of respiration had an influence on thoracic conformation objectively evaluated at multiple vertebral levels.

A new human cadaver model for laparoscopic training using N -vinyl-2-pyrrolidone: a feasibility study

Abstract

The demand for cadavers for clinical skills training is increasing. However, conventional formalin-fixed bodies are often unsuitable for surgical training because the tissues become too hard. We recently developed a new formalin-free embalming method with N-vinyl-2-pyrrolidone (pyrrolidone) that has excellent fixative, disinfectant, and preservative properties, while still keeping tissues soft and pliable. In the study reported here we investigated the feasibility of laparoscopic manipulation using pyrrolidone-fixed cadavers. Donated cadavers were embalmed either with pyrrolidone (n = 7) or with formalin-containing fixative (n = 3). A laparoscopic 12-mm trocar was inserted into the umbilical region, and CO2 gas was insufflated. Intra-abdominal structures were observed with an endoscopic camera. In the pyrrolidone-embalmed cadavers, the abdomen remained soft and depressed. In addition, CO2 injection resulted in a marked expansion of the abdominal cavity, and it was possible to move the laparoscope freely in all directions. Clear endoscopic images of the abdominal viscera were obtained. The gallbladder and rectum were identified by grasping the surrounding organs with forceps. By contrast, in the formalin-fixed bodies, the abdominal wall was rigid, and it was difficult to move the laparoscope in the peritoneal space and observe structures in detail. The amount of CO2 and changes in abdominal diameter and circumference in response to CO2 injection were significantly larger in the pyrrolidone group. In conclusion, we successfully created a sufficient pneumoperitoneum state and obtained clear endoscopic images in the pyrrolidone-embalmed cadavers. Handling and dissection of the intra-abdominal structures with forceps closely replicated real-life surgery. These findings suggest the feasibility of laparoscopic training on cadavers embalmed with this pyrrolidone fixative.

Anatomical entrapment of the dorsal scapular and long thoracic nerves, secondary to brachial plexus piercing variation

Abstract

Circumscapular pain is a frequent complaint in clinical practice. The dorsal scapular and long thoracic nerves course through the neck, where they may become entrapped between or within adjacent scalene muscles. Additionally, a high frequency of brachial plexus “piercing” variants have recently been documented, and it is unclear how they influence branching patterns distally along the brachial plexus. In the project reported here we strived to identify and quantify variations in dorsal scapular nerve and long thoracic nerve secondary to brachial plexus piercing variation. Ninety brachial plexuses from human cadavers (45 female/45 male) were evaluated to identify nerve branching patterns, specifically piercing versus non-piercing variants in the brachial plexus roots and nerves. Anatomical entrapment of the dorsal scapular nerve and long thoracic nerve was found in high frequencies (60.8% and 44.6%, respectively). Anomalous brachial plexus piercing variants were associated with higher frequencies of distal nerve branches also coursing through the scalene musculature, and there was a statistically significant correlation between brachial plexus and long thoracic nerve piercings (p = 0.027). Anatomical entrapment of nerves within scalene musculature is common and may be causative factors for idiopathic circumscapular pain, dorsalgia, and dysfunction of scapulohumeral rhythm. This study revealed a link between anatomical arrangement of the brachial plexus and occurrence of long thoracic nerve entrapment, which may lead to a series of cascading neurologic effects in which affected individuals may suffer from increased incidence of thoracic outlet syndrome and long thoracic nerve entrapment resulting in additional symptoms of interscapular pain and compromised shoulder mobility.

Differences in the shape and direction-course of the nasopalatine canal among dentate, partially edentulous and completely edentulous subjects

Abstract

We aimed to analyze the nasopalatine canal shape and anatomical variations of the buccal bone wall and compare the effect of the presence or absence of the central maxillary incisors on the nasopalatine canal. The shape of the nasopalatine canal and the dimensions of the buccal bone wall were measured in 150 patients who underwent a cone-beam computed tomography study. We found that the most prevalent shape of the nasopalatine canal was funnel (31%) and the most common direction-course was slanted-straight (33%). The buccal bone wall in relation to the nasopalatine canal was thickest at the anterior nasal spine level and narrowest at the level of the most anterior-inferior point of the buccal cortex of the maxilla. A statistically significant difference was detected between morphology and direction-course of the nasopalatine canal and dental status. In sum, the study of the nasopalatine canal showed multiple variations. Precise knowledge of these variations may help to decrease the incidence of complications during implantology treatment and during facial and dental surgery.

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