Boycho Landzhov

Medical University of Sofia · Department of Anatomy Histology and Embryology

In the area of upper extremity lipomas larger than 5 centimeters are accepted as giant. In the current article, we describe a case of a giant lipoma that included the muscles of the first extensor compartment before entering through it in a 49-year-old lady. The patient was successfully treated by excision of this tumor. The diagnosis and treatment...

Анатомичните вариации на каротидните арте�рии могат да бъдат причина за патологичен кръво�ток и развитие на атеросклероза и да са рисков фак�тор за мозъчно-съдова болест и инсулт. Мозъчният инсулт е сред водещите причини за инвалидизация и смъртност в света. Също така, нетипичният ход на каротидните артерии може да представлява риск при хирурги...

Hibernomas, rare benign tumors originating from brown adipose tissue, pose diagnostic challenges due to their infrequent occurrence and slow growth. We present a case of a 38-year-old woman with a progressively enlarging mass in her right lateral chest wall, initially stable in size but growing during pregnancy and causing pain and functional impai...

Recent studies have suggested a connection between disturbances of the apelin system and various cardiac pathologies, including hypertension, heart failure, and atherosclerosis. Vascular endothelial growth factor is crucial for cardiac homeostasis as a critical molecule in cardiac angiogenesis. Neuronal nitric oxide synthase is an essential enzyme...

The aim of this study is to investigate whether the dorsal claustrum receives afferent input from the intralaminar thalamic nuclei - centromedian nucleus, central lateral nucleus and paracentral nucleus. The intralaminar thalamic nuclei of eight cats were electrolytically lesioned. We obtained samples from the dorsal claustrum for electron microsco...

The adipocyte-derived hormone, leptin, plays a key role in the maintenance of energy homeostasis. Leptin binds to the long form of its receptor, which is predominantly expressed in various hypothalamic regions, including the lateral hypothalamic area (LH) and supraoptic nucleus (SO). Several studies have suggested that leptin directly activates neu...

The human knee is a complex joint that comprises several ligaments, including the medial collateral ligament (MCL). The MCL provides stability to the knee and helps prevent its excessive inward movement. The MCL also has a thin layer of connective tissue known as the epiligament (EL), which adheres to the ligament. This unique feature has drawn att...

Accessory bones around the elbow are scarce, with a reported mean incidence rate of 0.77%. The rarest one is the os supratrochleare anterius, with only a handful of documented cases in the literature. Despite their scarcity, various types of ossicles have been documented, posing diagnostic challenges and potential misinterpretation on X-rays. Herei...

The aim of this study was to assess the epiligament theory by determining the normal epiligament morphology of the proximal and distal parts of the anterior cruciate ligament in humans and analyzing the differences between them and the midportion of the ligament in terms of cell numbers and expression of CD34 and α-SMA. Samples were obtained from t...

The thyroidea ima artery (TIA), also known as the Neubauer artery, is a variable artery that takes part in the blood supply of the thyroid gland. The overall prevalence rate of the thyroidea ima artery is 3.3%. Though it most commonly branches off the brachiocephalic trunk or the arch of the aorta, the artery has a highly variable origin point. Her...

Observing anomalies in the origin of the coronary arteries is a rare but recognised scenario during coronarography. All the major coronary arteries originating from the right sinus of Valsalva is an extremely rare anomaly, its reported incidence being 0.008% in angiographic studies. Most coronary artery variations are benign and are therefore found...

In the current study, we investigated the effect of creatine monohydrate (CrM) and newly synthesized creatine lysinate (CrLys) in tail suspension (TST) and rotarod tests and their influence on the histology of the skeletal muscles. In the TST, a slight decrease in the immobility time from the 1 st to the 3 rd week was observed in the group treated...

In our study we investigated the acute toxicity of а newly synthesized creatine lysinate as well as its effect on the biochemical parameters in mice. Creatine lysinate exerts better solubility in water (3.3%) in comparison to creatine monohydrate (1.4%) at 20 °C and it is determined as a non-toxic after intraperitoneal (LD50 – 4543 mg/kg) and oral...

Background: The present study investigates whether vitamin D receptor (VDR) gene polymorphisms play a role in intervertebral disc degeneration (IDD), a common cause of low back pain (LBP) and reduced quality of life. Specifically, we examined the FokI VDR polymorphism and its potential association with lumbar disc herniation (LDH) in patients from...

Muscle variations in the posterior neck region are mainly categorized as variations in the origin and insertion of the muscles and the presence of accessory slips or rudimentary muscles. The levator scapulae muscle is a variable muscle with several different types of variations described throughout the literature. Herein, we report a rare unilatera...

Fibrous histiocytoma is a benign tumor involving soft tissues that can present as a fibrous mass involving various areas of the human body. Herein, we present a case of benign fibrous histiocytoma in the left brachium in a 14-year-old boy treated with surgical excision.

Accessory bones in the elbow region are rare anatomical variations with important clinical significance as they can be misdiagnosed as pathological lesions. Usually, they are asymptomatic and found incidentally during X-ray examination in the context of trauma. Although these bones have been previously described, their development is not fully unde...

Congenital malformations of the urogenital system with fully developed duplications, such as urinary bladder, are sporadic. They are often present in the setting of endogenous molecular disbalance, such as steroid metabolism disturbances. Other rare manifestations of hormonal disbalance present as intersex conditions in which the individual has kar...

Variations in the origin of the right coronary artery have an incidence between 0.09 % and 0.92 %. Herein, we report a rare case of a coronary artery anomaly in which the right coronary artery originates from the left main coronary artery. This variant was found during routine coronarography, combined with an artificial aortic valve. Despite their...

Changes in the microcirculation of multiple tissues and organs have been implicated as a possible mechanism in physiological aging. In particular, vascular endothelial growth factor is a secretory protein responsible for regulating angiogenesis via altering endothelial proliferation, survival, migration, extracellular matrix degradation and cell pe...

Detailed knowledge of the anatomy and different variations of the superficial branch of the radial nerve could be of great importance not only to anatomists but also to clinicians. A predominant radial nerve supply to the dorsum of the hand is rare. Herein, we present an unusual case of unilateral sensory innervation of the dorsal hand found during...

A sesamoid bone in the elbow joint is a rare anatomical variation described as a Patella cubiti. Although this variation has been known for centuries its exact etiology is still unclear. Congenital, developmental, and traumatic hypotheses have been proposed. It seldom causes clinical manifestations than elbow stiffness or hypomobility. Herein, we p...

Background: Vascular endothelial growth factor (VEGF) is a signalling protein of critical importance for angiogenesis. In an effort to better understand its significance in hypertension-induced injury of the heart and kidney we aimed at studying the changes in its expression in an experimental model and correlated it with capillary density in the...

Lipomas have been called “innocent tumors” due to their slow growth without infi ltrating neighbouring structures, usually with a rounded or ovoid shape, rarely over 2 cm in size. In the area of the upper limb, lipomas over 5 cm are defi ned as “giant lipomas”. In this report, we present a rare case of a “giant lipoma” in the hand in a 60-year-old...

Observing anomalies in the origin of the coronary arteries is a rare but recognized scenario during coronarography. All the major coronary arteries originating from the right sinus of Valsalva is an extremely rare anomaly, its reported incidence being 0.008% in angiographic studies. Most coronary artery variations are benign and are therefore found...

Background This study evaluated and compared the expression of VEGF, CD34, and α-SMA in the anterior cruciate ligaments and medial collateral ligaments in healthy human knees in order to enrich the epiligament theory regarding ligament healing after injury. Methods Samples from the mid-substance of the anterior cruciate ligament and the medial col...

From a topographical standpoint, the digastric muscle is key to the formation of several triangles of the neck, which are of the utmost clinical significance. Herein, we present a previously unrecognized variation of the digastric muscle: a quadrigastric muscle with two accessory bellies originating from the body and angle of the mandible and inser...

The metopic suture is a mid-sagittal plane variant of cranial syndesmosis, visualized from the nasion to the bregma. In most cases, the metopic suture closes during the first year of age; however, there are rare occurrences of persisting metopic suture in adults. Metopism is caused by incomplete fusion of the two embryological halves of the frontal...

The superior laryngeal artery is the primary vessel providing the blood supply to the larynx. Commonly, it is derived from the superior thyroid artery. Different variations in the origin have been described in the current literature; knowledge of such variations is crucial for various surgical interventions of the larynx and surgical procedures in...

Entrapment neuropathies are common and are frequently encountered by physicians in clinical practice. Median nerve entrapment, being one of the most common neuropathies in the upper extremity, must be studied in detail if the extent of injury it can cause is to be understood fully. Various anatomical variations are discovered frequently and reviewi...

Age-related morphological and physiological changes occur in cells, tissues and organs with high metabolic or mitotic activity; these changes decrease their regenerative capacity. One such change is interstitial fibrosis. Mast cells contain basic fibroblast growth factor and have been related to pro-fibrotic activity. We investigated the role of ma...

According to current literature, 90% of knee ligament injuries involve the medial collateral ligament or the anterior cruciate ligament. In contrast to the medial collateral ligament, which regenerates relatively well, the anterior cruciate ligament demonstrates compromised healing. In the past, there were numerous studies in animal models that exa...

Detailed knowledge of the anatomy and different variations of the superficial branch of the radial nerve could be of great importance not only to anatomists but also to clinicians. A predominant radial nerve supply to the dorsum of the hand is rare. Herein, we present an unusual case of unilateral sensory innervation of the dorsal hand found during...

The aim of this study was to assess the effect of newly synthesized derivatives of 4-aminopyridine (4-AP) on cuprizone-induced model of brain demyelination in mice. 4-AP is already approved for the treatment of walking difficulties in patients with multiple sclerosis. The model of demyelination was carried out by the administration of cuprizone to...

Идиопатичната калцификация на междупрешленните дискове, макар и рядка, остава важна нозологична единица в диференциалнодиагностично отношение на болките в гръбначния стълб при деца. Образните изследвания са основен диагностичен и диференциалнодиагностичен метод. Обикновено еволюцията на това състояние е добра с пълно възстановяване, както клинично,...

Hypertension is among the disorders with the highest impact on human health and healthcare systems around the world. It is responsible for various pathological conditions, which lead to a shortened life expectancy. There are multiple studies on the effects of prolonged hypertension on the heart and kidneys. While much is known about the structural...

Carpal tunnel syndrome is the most common nerve entrapment syndrome in the upper extremity. In cases of failure of conservative treatment, surgical treatment is usually recommended. Nowadays, for reduction of the complications endoscopic or different mini-incision techniques are developed. In the current study we present the results after mini inci...

Two of the most commonly discussed types of human intervertebral disc (IVD) herniations are protrusions and extrusions. The aim of this study was to compare expression of nitric oxide in both of them by means of histo-chemical study with nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d). The degree of herni-ations was assessed by MRI...

Detailed knowledge of the anatomy and different variations of the saphenous nerve could be of great importance not only to anatomists but also to clinicians. There are very few studies of saphenous nerve morphology in thigh. Most of the reported variations of this nerve concern the infrapatellar branch. In contrast, a saphenous plexus has been desc...

The aim of the present study was to evaluate the importance of the epiligament for the difference in the healing potential of the knee anterior cruciate and medial collateral ligament. To do so, we compared the structure of the anterior cruciate and the medial collateral ligament and evaluated the differences in the expression of collagen types I,...

Alzheimer’s disease (AD) is an age-related neurodegenerative disorder clinically characterized by memory impairment, disorientation, cognitive deficits, and behavioral disturbances. The neuropathological features are amyloid plaques containing aggregated amyloid-beta (Aβ) peptide, neurofibrillary tangles composed of the hyperphosphorylated form of...

Обогатената на тромбоцити плазма представлява автоложен концентрат от различни клетки (най-вече тромбоцити) и растежни фактори, придобити от центрофугирана кръв с нарастващи доказателства за приложението и при различните специалности. Доказано е, че високата концентрация на растежни фактори активира клетъчната пролиферация и диференциация. В литера...

Hypertensive nephrosclerosis is characterized by increased prevalence of sclerotic glomeruli, thickening of the glomerular and tubular basement membranes, altered morphology of the glomerular filtration barrier, tubular atrophy and interstitial fibrosis. These changes have been discussed in different experimental models of rats, but it seems that t...

Leptin is an adipokine that plays an important role in the regulation of energy homeostasis. The failure of endogenous and exogenous leptin to mediate its effects (for example, at suppressing appetite and decreasing body weight) has been termed leptin resistance. Hyperleptinemia and leptin resistance can be well demonstrated in animals in which obe...

4-aminopyridine blocks a wide variety of voltage-activated potassium (Kv) channels that are distributed across multiple cell types in the central nervous system (neurons, oligodendrocytes, and microglia) as well as in the immune system (T and B cells, macrophages, and dendritic cells). The blockade of potassium (K+) channels has demonstrated the ab...

Hypertension-induced renal injury is a multifactorial process which plays a crucial role in the development of chronic kidney disease. Multiple studies have demonstrated that interstitial rather than glomerular changes correlate better with renal functional capacity. Recent evidence indicates that mast cells and cell signaling proteins such as fibr...

Palmaris longus (PL) and flexor digitorum superficialis muscles (FDS) are some of the variable muscles in the human body. The absence of PL and FDS tendon of the little finger are the two most frequently reported variations. The aim of the study was to analyse the absence of PL and absence of FDS tendon of the little finger with clinical tests. We...

Introduction An increasing number of studies have shed light on the role of cardiac mast cells in the pathogenesis of hypertension-induced myocardial remodeling. Mast cells promote fibroblast activation, myofibroblast differentiation and subsequent collagen accumulation through the action of tryptase, chymase, histamine and fibroblast growth factor...

The transradial approach has been preferred compared to conventional transfemoral approach and/or transbrachial approach. Failure of the transra-dial approach has been reported in 1-5% of cases. Anatomical variations of the radial artery, however, could pose significant challenges to the interventional cardiologist and are the second most frequent...

Leptin is a peptide hormone regulating food intake and body weight. The effects of leptin are mediated via leptin receptors present in the central nervous system (including hippocampal regions and gyrus dentatus). It is known that leptin induces phosphorylation of the neuronal isoform of nitric oxide synthase (nNOS) in defined hypothalamic regions....

Renal fibrosis is characterized by increased synthesis of collagen molecules in the renal parenchyma and interstitium. In the present study, we demonstrated the expression of collagen types I and V and procollagen type III in the renal structure of 12-month-old spontaneously hypertensive rats and age-matched Wistar rats. The main findings included...

The established decrease in the level of endogenous kyotorphin (KTP) into the cerebrospinal fluid of patients with an advanced stage of Alzheimer’s disease (AD) and the found neuroprotective activity of KTP suggested its participation in the pathophysiology of the disease. We aimed to study the effects of subchronic intracerebroventricular (ICV) tr...

The claustrum is a subcortical nucleus, found in the telencephalon of all placental mammals. Earlier Golgi studies have mostly focused on a qualitative description of the types of neurons. The aim of the present study was to describe the types of neurons found in the dorsal claustrum of the cat using the Golgi impregnation method and to perform a q...

Leptin is an adipokine that regulates body weight by decreasing appetite and increasing energy expenditure. Besides the effects on food intake, leptin can regulate energy expenditure at least in part by modulating thermogenesis. Many of the effects of leptin are attributable to action in the central nervous system, particularly in the hypothalamus....

Leptin, a hormone mainly produced by adipocytes in proportion to fat mass, is a key component in the regulation of energy homeostasis and reproductive, neuroendocrine, immune, and metabolic functions. Leptin binds to the leptin receptor, which is expressed throughout the central nervous system but particularly in neurons of several nuclei of the hy...

Herein we present a case of a traumatic injury to the right index finger by an electric screw gun. The screw entered the finger through the medial part of the proximal interphalangeal joint and ended in the middle phalanx, therefore we will discuss bone damage. We point out the approach for immediate treatment, including the use of a screwdriver in...

The present work reviews the distribution of neuronal nitric oxide synthase in the kidney and its role in various renal functions. A review of the literature shows that most authors have focused on the endothe-lial isoform as the primary source of nitric oxide production in kidneys. Nowadays, there is convincing evidence that renal neuronal nitric...

The medial collateral ligament of the knee joint is one of the most commonly injured ligaments of the knee. Recent data have shown that the thin layer of connective tissue covering the ligament, known as the epiligament, is essential for its nutrition and normal function, as well as its healing after injury. The aim of the present study was to inve...

The giant cell tumour of bone (GCTB) is described as an osseous neo-plasm that is histologically benign but clinically shows local aggression and rarely "benign" pulmonary metastases or undergoes malignant transformation. The World Health Organisation has classified it as "an aggressive, potentially malignant lesion". There are many unanswered ques...

[This corrects the article DOI: 10.7759/cureus.3812.].

Background: The claustrum is the most densely connected brain structure by volume and has extensive reciprocal connections with numerous cortical areas. It is divided into two embryologically distinct parts – dorsal and ventral claustrum. Despite numerous recent findings, much remains unknown about its structure and function. Objective: The aim of...

Синдромът на карпалния канал е най-често срещаната компресионна мононевропатия на горния крайник. В карпалния канал n. medianus лежи между retinaclum flexorum отгоре и сухожилията на флексорната група мускули и карпалните кости отдолу. В литературата има описани редица анатомични вариации, засягащи както анатомичните структури, оформящи карпалния к...

Introduction: Recent studies stressed the importance of the epiligament in ligament nutrition and healing. While ligaments of the knee joint have been the subject of extensive research, the epiligament of the medial collateral ligament has received only limited attention. The aim of our study was to present the ultrastructural morphological feature...

The claustrum is a subcortical nucleus found in the telencephalon of all placental mammals. It is a symmetrical, thin and irregular sheet of grey matter which lies between the inner surface of the insular cortex and the outer surface of the putamen. The claustrum has extensive connections with the visual, auditory, somatosensory and motor regions o...

The lunate bone is a carpal bone which can be easily distinguished by its crescent outline. The bone has its role in orthopedics and the related pathologies are difficult for diagnostics. The aim of our work was to overview the morphological characteristics of the bone which have significant role in pathological conditions of the wrist, like Kienbo...

The acromion is one of the two processes of the scapula. It plays a role in the field of orthopedics by having a correlation with some diseases. The morphology of this process has a significant role in upper limb pathology. The aim of the present study was to describe the different types of acromion process based on its morphology and to discuss it...

Aim Ninety percent of knee ligament injuries involve the medial collateral ligament (MCL) and the anterior cruciate ligament (ACL) of the knee joint. Matrix metalloproteinases (MMPs) are a large group of calcium- and zinc-dependent endopeptidases responsible for cleaving and rebuilding various connective tissue components. Previous studies showed t...

Background: The claustrum is a brain structure found in both hemispheres beneath the inner surface of the neocortex in the region of the insula and is bordered by the external and extreme capsule. Generally, it is divided into a dorsal part (claustrum proper or insular claustrum) and ventral part (endopiriform nucleus). The claustrum possesses comp...

Background: The growth of the heart during the foetal and early postnatal development takes places mainly due to hyperplasia. The late postnatal development is characterised by cardiomyocytic hypertrophy in response to normal physiological mechanisms and increased load. To study the cell size most authors measure the diameter either directly or ind...

Objectives: We investigated the mutual effects of overt hypothyroidism and prolonged sunlight exposure on free radical accumulation and oxidative skin damage. Methods: Free radical accumulation was evaluated by monitoring the transformation of 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) into MTT-formazan. The pro-oxidant enzy...

Renal senescence is characterized by numerous morphological alterations, which are associated with reduction in the renal functional capacity. Glomerulosclerosis is a nonspecific feature observed in the normal process of aging, as well as in pathological conditions such as hypertension and diabetes. In literature, two types of sclerotic glomeruli h...

Over the last decade, the transradial approach has become the preferred method for heart catheterization during diagnostic and therapeutic procedures. Compared to the more traditional transfemoral approach, it has significant advantages, including easier hemostasis, lower vascular complications (such as bleeding, thrombosis, fistulas and pseudoaneu...

A number of morphological studies on the ultrastructure of the myocardium show that myocardial hy-pertrophy is associated with hypertrophy of the individual cardiomyocytes, as well as an increase in their number (hyperplasia), hyperplasia of the cellular organelles, alterations in cell nuclei and interstitial proliferation. The various subcellular...

Background: Differences in the size of cardiac muscle cells observed in normal and hypertrophic hearts have been assessed through different methodologies. Spontaneously hypertensive rats are often used as an experimental model of essential hypertension in humans, which allows researchers to study the relation between hypertension and cardiac hyper...

During a routine anatomical dissection of the right brachium of a 68-year-old male cadaver, an extremely rare variation of the coracobrachialis longus muscle was discovered. It started from the medial surface of the middle part of the humerus with a well-formed muscle portion and then continued into the well-presented distal tendinous portion, whic...

Alzheimer's disease (AD) is a widespread neurodegenerative disease associated with a progressive loss of memory, which occurs after prolonged pre-symptomatic phase. In the process of searching for new biomarkers for early diagnosis of the disease, reduced levels of endogenous dipeptide kyotorphin (KTP) were found in the cerebrospinal fluid of peopl...

Purpose The extensor indicis proprius (EIP) is a muscle of the forearm that originates from the posterior surface of the ulna and the adjacent interosseous membrane and attaches to the index finger. Many anatomical variations of this muscle have been reported in the literature. The extensor digitorum brevis manus (EDBM) is a variant muscle found on...

Introduction: Spontaneously hypertensive rats are often used as a model of arterial hypertension in humans. Cardiomyocytic hypertrophy, focal myocytolysis and ventricular fibrosis are only a part of the alterations in the morphology of the myocardium observed in spontaneously hypertensive rats with the progression of hypertension. The present manus...