Folia morphologica最新文献

Knowledge of the configuration of root canals is essential for the success of endodontic treatment. The main aim of this systematic review was to determine the number of roots and the number of root canals in maxillary third molars, as well as where possible to determine the Vertucci classification. This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement guidelines. The study protocol was registered and approved on PROSPERO, the International Prospective Register of Systematic Reviews (Reg. No: CRD42022366444), before the start of the study. 12 studies were included in the analysis, differing in sample origin and methodology. The combined studies were analysed based on the number of roots, the number of canals, and the root canal configurations, and the findings were compared to those of other international studies. Analysing the available research results regarding the root anatomy and canal configuration of the third maxillary molar, most commonly maxillary third molars had three roots (59.0%). Single-rooted teeth (24.2%) or double-rooted teeth (13.8%) were less common. In addition, we observed that maxillary third molars typically possessed three root canals (47.28%) and the MB (mesiobuccal), DB (distobuccal), and P (palatal) canals most often showed Vertucci Type I (59.53%, 95.83% and 98.61%, respectively) in three-rooted form. Due to the small number of available studies, it is necessary to conduct further analyses taking into account demographic and ethnic differences that may affect the anatomical and morphological structure of the teeth.

Background: In recent years, elucidating the actual state of the liver nervous system has attracted attention, owing to clinical needs, such as liver transplantation. Conventional methods for studying the intrahepatic nerve distribution mostly use liver tissue sections, specific markers for immunohistological studies, or anterograde/retrograde tracing in animals. However, knowledge of the three-dimensional structure of intrahepatic innervation is vague or speculative.

Materials and methods: In this study, Suncus murinus (n = 10) were perfused and fixed, the livers were excised, and the liver parenchyma was carefully removed, leaving only the intrahepatic vasculature. Specimens were prepared to study the three-dimensional structure of Suncus murinus intrahepatic and hilar innervation by whole-mount immunohistochemical staining using a neurofilament protein antibody.

Results: After the nerves running along the intrahepatic arterial system entered the liver parenchyma from the hepatic hilum, they maintained a relatively rich distribution along the interlobular arteries until the distal end. The innervation of the portal system began to decrease after entering the liver parenchyma and decreased significantly after reaching the deep parts. By the time it reached the end of the interlobular vein, there was very little left. The number of nerves running along the intrahepatic bile duct system was significantly reduced after entering the porta hepatis, and innervation was difficult to observe after completely entering the liver parenchyma.

Conclusions: Whole-mount immunohistochemical analyses with an anti-NFP antibody showed that intrahepatic innervation mainly accompanied the hepatic interlobular arteries and extended to their terminal ends. Neuronal regulation is very important in the functional regulation of intrahepatic nutritional vessels. However, there were very few NFP-immunoreactive nerves accompanying the intrahepatic bile duct system, possibly suggesting that the functional regulation of the intrahepatic biliary system mainly relies on hormones and neuropeptides.

The lumbar plexus is a collection of nerves, and it originates from the anterior rami of the T12-L5 laterally to the intervertebral foramina. It gives off 6 peripheral nerves, and in the available literature there are a lot of descriptions of each nerve and its possible morphological variations. In some cases, the occurrence of accessory nerve or absence of whole nerve is observed. In other cases, morphological variations regarding the origin, course, or division into more branches are also noticed. Such variations may be associated with some clinical aspects. Understanding the anatomical variations of the lumbar plexus's nerves is essential for procedures involving the lower abdomen, regional anaesthesia, and managing nerve entrapment syndromes. The main aim of this review is to present condensed information on the lumbar plexus based on the available literature. A further aim is to compare the classification systems and the results of previous studies in adults and foetuses. This manuscript also includes information on the most common clinical implications associated with anatomical variations of the individual nerves of the lumbar plexus.

Background: Considering the tortuous course of the facial canal that houses the facial nerve, the stylomastoid artery, and the homonymous vein, its morphological features are of great clinical significance in otologic, maxillofacial, oncologic, reconstructive and plastic surgery of the head and neck. The aim of this paper was to determine the individual specific features of the mastoid segment of the facial canal and of the stylomastoid foramen.

Materials and methods: The study was carried out on 82 temporal bones (41 right/41 left), at the Department of Anatomy and Clinical Anatomy of Nicolae Testemitanu State University of Medicine and Pharmacy of the Republic of Moldova. The morphometry of the mastoid segment of the facial canal and of the stylomastoid foramen was performed. The morphometric parameters were statistically analysed by descriptive and inferential statistics methods.

Results: The mastoid segment exited the facial canal at obtuse, right and sharp angles, with a mean value of 113.1 ± 21.80° (right/left - 112.1 ± 23.85°/114.1 ± 19.76°), p = 0.701. The mean length of the mastoid segment was 15.1 ± 3.78 mm (right/left - 15.7 ± 3.66 mm/14.5 ± 3.84 mm), p = 0.153. The longitudinal diameter of the stylomastoid foramen had a meanof 3.0 ± 0.93 mm (right/left - 3.3 ± 0.96 mm/2.7 ± 0.81 mm), p = 0.007. The transverse diameter had a mean of 2.6 ± 0.74 mm (right/left - 2.9 ± 0.80 mm/2.4 ± 0.60 mm), p = 0.012.

Conclusions: In otologic surgery, particularly in mastoidectomy, it should be taken into consideration that the mastoid segment of the facial canal could exit the temporal bone at sharp, right and obtuse angles. This peculiarity, along with high morphological variability of the stylomastoid foramen, might be a predisposing factor for Bell's palsy.

Background: Monosodium glutamate is a food additive and flavour enhancer in processed foods and soups that is considered to affect testicular histology. The aim of this research was to investigate the impact of monosodium glutamate (MSG) on testicular structure in rats and explore the potentially protective effects of resveratrol.

Materials and methods: Four experimental groups involved in our study contained 10 rats in each. The first group was a control group; in the second group (the resveratrol group) control rats received 20 mg/kg of resveratrol via oral gavage; in the third group (the MSG group) rats received monosodium glutamate (MSG) at a dose of 60 mg/kg body weight daily, via a gastric tube. The fourth group we called the MSG + resveratrol group. Serum levels of testosterone, FSH, and LH were measured. Testicular specimens were prepared for measurement of oxidative stress markers, and gene expression of NLRP3, caspase-3, and GSK-3b. Moreover, paraffin blocks contained testicular tissue used for histological and immunohistochemical examination. Additionally, seminal smears from epididymis were examined.

Results: MSG administration adversely affected testosterone production, hormonal levels, and sperm parameters, Histological examination revealed marked testicular degeneration, and oxidative stress assessments indicated an elevated level of MDA, a lipid peroxidation marker, and decreases in SOD and CAT, two antioxidant enzymes. Moreover, MSG induced apoptotic and pyroptotic markers and its gene expressions. Importantly, the administration of resveratrol reversedthese detrimental effects of MSG, demonstrating its corrective influence on hypothalamic-pituitary-gonadal axis disruption, the improvement of sperm parameters, the attenuation of oxidative stress, and anti-apoptotic activity and anti-pyroptotic effects. The expression of Ki-67 as a cell proliferation marker further supported the positive response to spermatogenesis dysfunction upon resveratrol treatment.

Conclusions: This article sheds light on the protective effect of resveratrol against MSG-induced testicular damage, with an exploration of its mechanistic role.

Background: Bone morphogenetic proteins (BMPs) are used in clinical practice for the stimulation of bone formation, but can often lead to serious complications. Recent studies have demonstrated that BMPs involved in the early stages of bone formation are species-specific. In cattle the most common forms encountered are BMP7, growth differentiation factor 5 (GDF5), and NEL-like protein 1 (NELL1), while in rats the most common are BMP2, BMP5 and BMP6. The aim of this study was to compare the action of species-specific BMPs on osteoprogenitor cells. Thus, rat osteoprogenitor cells were exposed to one BMP in a high dose, and three of them at one third of the high dose.

Materials and methods: Isolated rat osteoprogenitor cells were treated in culture with different concentrations of BMP2, BMP5 and BMP6 or with lower concentrations of combinations of these cytokines. The activity of alkaline phosphatase, calcium deposition and mRNA level for transcription factor SP7 (osterix) and tissue non-specific alkaline phosphatase (TNAP) served as indicators of BMPs effect.

Results: BMPs stimulated all studied parameters compared to control cultures, but no statistically significant differences were observed between the action of a large dose of one cytokine and a combination of cytokines given at lower concentrations.

Conclusions: Three BMPs used in a low dose exert a similar effect to one used in a high dose. Since the BMPs stimulate different receptors, and activate different signalling pathways, using a mixture of properly chosen BMPs at a low concentration may give better results than a single one at a high concentration, and may avoid untoward effects.

Background: Although radiofrequency ablation of the cavotricuspid isthmus (CTI), responsible for sustaining atrial flutter, is a highly effective procedure, in extended patient observations following this procedure, more than 10% becomeunsuccessful. Therefore, this study was aimed at providing helpful information about the anatomy of the CTI in transthoracic echocardiography, which could aid better planning of CTI radiofrequency ablation in patients with typical atrial flutter.

Materials and methods: 56 patients with typical atrial flutter after radiofrequency ablation were evaluated at the end of a 24-month observation period. With substernal modified transthoracic echocardiographic (mTTE) evaluation, we identified four main anatomical obstacles impeding radiofrequency ablation: tricuspid annular plane systolic excursion, cavotricuspid isthmus length, cavotricuspid isthmus morphology, and the presence of a prominent Eustachian ridge/Eustachian valve. All intraprocedural radiofrequency ablation data was collected for analysis and correlated with anatomical data.

Results: Over a 24-month observation period, freedom from atrial flutter was 67.86%. The mean length of the isthmus was 30.34 ± 6.67 mm. The isthmus morphology in the 56 patients was categorised as flat (n = 27; 48.2%), concave (n = 10; 17.85%), or pouch (n = 19, 33.9%). A prominent Eustachian ridge was observed in 23 patients (41.1%). Lack of anatomical obstacles in mTTE evaluation resulted in 100% efficacy, while the presence of at least two obstacles significantly increased the risk of unsuccessful ablation with more than two (OR 12.31 p = 0.01). Generally, 8 mm electrodes were the most effective for non-difficult CTI, while 3.5 mm electrodes used with a 3D system had highest performance forcomplex CTI. Notably, ageing was the only factor that worsened the long-term outcome (OR 1.07 p = 0.044).

Conclusions: Preoperative use of mTTE evaluation helps predict difficulty in cavotricuspid isthmus radiofrequency ablation, thus allowing better planning of the radiofrequency ablation strategy using the most accurate radiofrequency ablation electrode.

Background: The superior mesenteric vein appears as a fusion between irregularly-shaped slits of the midgut mesentery tissue at 5-6 weeks. In contrast, there might be no report when and how the inferior mesenteric vein (IMV) develops. We aimed to find the human initial IMV.

Materials and methods: We examined 1) sagittal histological sections of 7 human fetuses with 45-75 mm crown rump length or CRL (10-12 weeks); 2) horizontal sections of 15 fetuses with 70-155 mm CRL (12-18 weeks) and 3) horizontal sections of 12 late-term fetuses with 225-328 mm CRL (28-41 weeks).

Results: In the mesentery of the descending colon-rectum, the initial IMV lumen opened at 10-12 weeks of gestation, but the vein was difficult to trace upward to the anterior surface of the left adrenal. At 13-14 weeks, irrespective of whether it accompanied a colic artery, the IMV ran medially along the adrenal and it sometimes became thick near the pancreatic head. Earlier than the IMV, the middle colic vein appeared at the left aspect of the pancreatic head. Until late-term after establishment of the dorsal mesogastrium fusion with the mesocolon transversum, the IMV provided a peritoneal fold at the duodenojejunal junction.

Conclusions: A venous drainage via the IMV was much delayed possibly because, in early and midterm fetuses, an ongoing fusion of the midgut mesentery and a changing topographical relation among the abdominal viscera interfered with the venous flow. Instead, well-developed lymphatics seemed to be responsible for the drainage of the left-sided colon.

Background: Surfactant protein-A (SP-A) is the most prevalent protein in the pulmonary surfactant system and it is expressed in Type II alveolar epithelial cells.

Materials and methods: We evaluated SP-A expression in 92 fetal human lungs at various gestational ages in Myanmar (Burma) using hematoxylin and eosin staining and immunohistochemical assays.

Results: We detected tubular structures in the fetal lungs during the canalicular stage of development at gestational weeks 22-25. Bronchioles were detected between 26-27 and 28-33 weeks, when primitive alveoli were evident. At 34-40 weeks, clusters of alveolar sacs opened from the alveolar ducts during the saccular development stage. At 40-44 weeks, extremely thin alveolar walls resembled sections of adult lungs. Type II cells secreting surfactant were undetectable at 22-25 weeks, but became detectable from 26 weeks, and the abundance of Type II cells increased after 28 weeks. Surfactant spread throughout the alveoli at 34 weeks. Because the positivity index of these cells significantly correlated with a gestational age of 26-33 weeks, we established a formula to estimate gestational age.

Conclusions: Our findings improve understanding of fetal lung development and maturity, and provide valuable insights into the diagnosis and management of respiratory disorders among premature infants in Myanmar.