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Biomedical subjects

M F Sargon

Publications and source records attributed to M F Sargon.

At least 19 recordsLinked to original sources
PubMed2003

A very rare anatomic variation of the left brachiocephalic vein: left retro-aortic brachiocephalic vein with tetralogy of Fallot.

An anomalous course of the left brachiocephalic vein behind the aortic arch was identified in a patient with tetralogy of Fallot. A 6-year-old male patient had been admitted to the hospital with a diagnosis of tetralogy of Fallot and patent foramen ovale. At the beginning of the operation the left brachiocephalic vein could not be found. The pericardium was opened longitudinally and there was no persistent left superior vena cava. After careful examination, the left brachiocephalic vein was found behind the aorta. Especially during open heart surgery this pathology is very important. We conclude that when the left brachiocephalic vein can not be found, the possibility of persistent left superior vena cava and retro-aortic left brachiocephalic vein should be borne in mind.

Aorta, Thoracic↗
PubMed2003

Quantitative analysis of myelinated axons of commissural fibers in the rat brain.

In this study, the myelinated axons of the rostrum, genu, truncus and splenium parts of the corpus callosum and of the anterior, posterior and habenular commissures were counted in the rat brain by using a camera lucida. The numerical densities of these axons were compared with each other by means of quantitative analytical statistical methods. In parts of the corpus callosum, a statistically significant difference was found between the rostrum and genu, rostrum and truncus, rostrum and the splenium, genu and truncus, and the genu and splenium. However, no statistically significant difference was found between the truncus and splenium. When comparing the number of myelinated axons of the anterior, posterior and habenular commissures, statistically significant differences were found between the anterior and posterior commissures, and between the anterior and habenular commissures. No statistically significant difference was found between the posterior and habenular commissures. Small sized myelinated axons were present in all parts of the corpus callosum and in the anterior commissure. However, a heterogeneous distribution of myelinated axons was present in the posterior and habenular commissures.

Animals↗
PubMed2002

Three-dimensional (3-D) reconstruction of the human coccygeal body.

The three-dimensional reconstructions of the human coccygeal bodies were undertaken using semi-thin serial sections which were cut from the tissue specimens taken from the ventral parts of the tip of the coccyges of four patients. The coccygeal bodies were observed in the form of convoluted, irregular helical tubes. The diameters of the coccygeal bodies in serial sections were measured and a statistical analysis performed. The lumens of the coccygeal bodies were not observed in the twisted parts of the tissue specimens. Depending upon to the irregular courses of the lumens and their lack of appearances in the twisted areas, we are unable to show the three-dimensional reconstructions of the lumens of the coccygeal bodies. In conclusion, this is the first study reporting the three-dimensional reconstruction of the contours of the coccygeal body. These type of studies, which were done by using serial sections will be very helpful for the understanding of the little known organs of the human body.

Adult↗
PubMed2001

High origin and unusual suprarenal branch of a testicular artery.

In a 42 year-old male cadaver, the left testicular artery was found to originate from the anterior surface of the abdominal aorta at the level of origin of the left renal artery. It ran parallel and just inferior to the left renal artery and gave off a branch which supplied the left suprarenal gland. The course, relations and branching of this suprarenal branch differed from the very rare cases found in the literature. Awareness of the possible existence of such variations of the testicular arteries is of great importance during surgical procedures.

Adult↗
PubMed2001

Effects of aminoguanidine on glomerular basement membrane thickness and anionic charge in a diabetic rat model.

We investigated the effect of aminoguanidine (AG) administration on GBM thickness, glomerular heparan sulfate (HS) content, and urinary albumin and HS excretion in diabetic rats. After induction of diabetes, female Wistar rats were divided into 2 groups: Group AGDM (n = 11) received 1 g/L aminoguanidine bicarbonate in drinking water, group DC (n = 12) was given only tap water. Control rats received AG (group AGH, n = 8) or tap water (group HC, n = 8). At the end of a period of 8 weeks, urinary albumin and glycosaminoglycan (GAG) excretion was detected. GBM heparan sulfate distribution and count was determined under the electron microscope. The AGDM group had lower urinary albumin and GAG excretion than diabetic controls. GBM thickness was increased in diabetic rats compared to groups of AGDM and HC. In AGDM group alcian blue stained particle distribution and count in the GBM was similar to healthy controls. In conclusion AG prevents the decrease of anionic charged molecules in the GBM and GBM thickening. This can be one of the mechanisms by which AG decreases albuminuria in diabetic rats.

Administration, Oral↗
PubMed2001

Effects of iloprost on vasospasm after experimental spinal cord injury: an electron and light microscopic study.

It has been increasingly reported that traumatic and ischemic insults to the spinal cord may produce tissue damage through both direct and indirect mechanisms. In spite of many theories about post-traumatic spinal cord injury, there is still no satisfactory account of the exact mechanism. Vasospasm may be related to the trauma and release of vasoconstrictor or vasoactive amines. This study aims at studying the possible protective mechanisms of iloprost, a stable analogue of prostacyclin, after spinal cord injury on the rabbit. Forty-two adult male rabbits (New Zealand albino) were inflicted injuries by epidural application of an aneurysm clip to the spinal cord. Twenty-one rabbits received an i.v. infusion of 25 microg kg(-1) x h(-1) iloprost. The remaining twenty-one rabbits received an i.v. infusion of saline as the control group. Intravenous treatment started immediately after the infliction of the spinal cord injury and lasted for 1 h. Iloprost treatment had no side effects on the general physiological parameters in the rabbits. Control and iloprost treatment groups were divided into three sub-groups. The first group of animals was deeply anesthetized and spinal cords were removed 15 min after treatment. Second and third group animals were sacrificed in the 3rd and 24th hours respectively. All spinal cords were removed for light and electron microscopic examination. The width of anteriolar smooth muscle cells and the ultrastructural analysis of sulcal arterioles and venules in the ventral median fissure of spinal cords treated by iloprost revealed less thickening in all groups especially on the 24th hour group (p < 0.01), but less thickening was observed on the 3rd hour group. Iloprost-treated groups had limited edema and moderate protection of myelin and axons. These results suggest that iloprost treatment after spinal cord injury has a highly protective effect, and the possible protective effect of iloprost is resolution of vasospasm due to spinal cord injury.

Animals↗
PubMed2000

Chitosan film enriched with an antioxidant agent, taurine, in fenestration defects.

A natural polysaccharide, chitosan (poly-N-acetyl glucosaminoglycan), which is a nontoxic and bioabsorbable polymer, has been shown to have hemostatic and antibacterial effects. An amino acid, taurine, is considered to be beneficial for regulating the inflammation process. The purpose of this study was to investigate the synergistic effects of taurine and chitosan in the experimental defects at the vestibular bone of maxillary canine teeth in six dogs. Chitosan films were prepared as delivery system with or without taurine and placed in the randomly chosen defects. Biopsies were performed on the postoperative seventh day and routine histological procedures were performed for light and electron microscopic evaluations. For each group, 30 different microscopic areas were examined and the numbers of macrophages and neutrophils in these areas were counted. The mean numbers of both macrophages and neutrophils were found statistically different between the chitosan film incorporated with taurine and free chitosan groups (p < 0.0001 p > 0.05). In addition to the increase in cell counts in both groups, the cytological alterations were more obvious in the chitosan film group incorporated with taurine. Accordingly, taurine appears to enhance the acceleration effect of chitosan on wound healing at early periods. This effect could be considered beneficial in tissue repair in destructive diseases like periodontitis.

Animals↗
PubMed2000

Chitosan films and hydrogels of chlorhexidine gluconate for oral mucosal delivery.

Topical delivery of antimicrobial agents is the most widely accepted approach aimed at prolonging active drug concentrations in the oral cavity. As most antifungals do not posses inherent ability to bind to the oral mucosa, this is best achieved through improved formulations. Chitosan, a partially deacetylated chitin, which is a biologically safe biopolymer, prolongs the adhesion time of oral gels and drug release from them. Chitosan also inhibits the adhesion of Candida albicans to human buccal cells and has antifungal activity. The antifungal agent, chlorhexidine gluconate (Chx), also reduces C. albicans adhesion to oral mucosal cells. The aim of this study was to design a formulation containing chitosan for local delivery of Chx to the oral cavity. Gels (at 1 or 2% concentration) or film forms of chitosan were prepared containing 0.1 or 0.2% Chx and their in vitro release properties were studied. The antifungal activity of chitosan itself as well as the various formulations containing Chx was also examined. Release of Chx from gels was maintained for 3 h. A prolonged release was observed with film formulations. No lag-time was observed in release of Chx from either gels or films. The highest antifungal activity was obtained with 2% chitosan gel containing 0.1% Chx.

Absorption↗
PubMed2000

Early protective effects of iloprost after experimental spinal cord ischemia in rabbits.

The potential role of Iloprost, a stable analogue of prostocyclin, in treating spinal cord ischemia was investigated in rabbits subjected to aortic occlusion for 15 minutes. Ten adult rabbits weighing 2-2.5 kg received an intravenous infusion of saline (SF) as a control group and 14 rabbits received an intravenous infusion of Iloprost, 25 microg/kg/h. Iloprost infusion was started immediately after clamping of the aorta and continued 60 minutes thereafter. Cortical somatosensorial evoked potentials (CSEP) were recorded during the pre-ischemic period as a baseline and post-ischemic readings were taken at 15, 30 and 60 minutes. There was no statistically significant difference between CSEP of the saline and Iloprost treated groups (p < 0.05). All animals were examined neurologically by using a modification of Tarlov scale and all subjects were then deeply anesthetized and their spinal cords were removed for light and electron microscopic examinations at 24 h after spinal cord ischemia. In order to obtain an accurate comparison of ultrastructural changes between saline treated and Iloprost treated groups, a grading scale was performed. The light microscopic and ultrastructural analysis of the Iloprost treated group revealed that there was moderate protection of the myelin and axons and edema was attenuated. Findings of this study suggest that Iloprost exerts a protective effect on spinal cord ischemia. However, further studies are needed to reveal possible mechanisms of protection provided by Iloprost.

Animals↗
PubMed2000

The early protective effects of L-arginine and Ng-nitro-L-arginine methyl ester after experimental acute spinal cord injury. A light and electron microscopic study.

The purpose of this study was to investigate the early protective effects of L-arginine and Ng-nitro-L-arginine methyl ester (L-NAME) after acute spinal cord injury. Acute spinal cord injury was performed by epidural application of an aneurysm clip at thoracic (T) 7 - 11 level. L-arginine at a dose of 750 microg/kg/min was administered 10 min before acute spinal cord injury and continued for 30 min to 10 animals (Group II). L-NAME at a dose of 250 microg/kg/min was administered 10 min before acute spinal cord injury and continued for 30 min to 10 animals (Group III). No drug was administered to 10 animals after acute spinal cord injury (Group I). Light and electron microscopic analysis were performed in all of the groups. Oedema of perineural, axoplasm or white matter in the L-arginine-treated group was less than in Group I and Group III. Thickening in the walls of the arterioles and venules in the L-arginine-treated group was much milder than in Group I and Group III. Degeneration of myelinated axons in the L-arginine-treated group was milder than in the control group. But there was no different between Group II and Group III.

Acute Disease↗
PubMed2000

The effect of povidone iodine on the corneal endothelium.

PURPOSE: Povidone iodine has been proven to be a valuable antiseptic solution in preparing the eye for surgery and is an alternative to postoperative topical antibiotics. No study has addressed the intraocular toxicity of povidone iodine after injection into the anterior chamber. We investigated the potential toxicity of povidone iodine on the corneal endothelium after injections into the anterior chamber in a rabbit model. METHODS: In this study we used 24 eyes of 12 albino rabbits. The eyes were divided into the following three groups according to the drugs tested: group A, 5% povidone iodine; group B, 10% povidone iodine; group C, balanced salt solution. The injected eyes were evaluated by biomicroscopy, specular microscopy, corneal pachymetry, and transmission and scanning electron microscopy. RESULTS: Corneal edema was observed in all eyes of groups A and B. In groups A and C, the endothelial cell morphology was not significantly changed and the mean endothelial cell count of the eyes did not change significantly (p = 0.5054). There was no significant difference in corneal thickness between groups A and C (p = 0.3823), but there was a significant difference between groups B and C ( = 0.0002). Transmission and scanning electron microscopy results were normal in group C but not in groups A and B. CONCLUSION: Povidone iodine in both 5% and 10% concentrations demonstrates severe toxicity when one drop of either concentration is placed directly in the anterior chamber. When povidone iodine is used in preparing the eye for intraocular surgery and as an alternative to postoperative antibiotics, the inadvertent leakage of povidone iodine into the anterior chamber must definitely be prevented.

Animals↗
PubMed1999

A new epineural nerve repair technique: oblique nerve coaptation.

Despite the existence of various nerve coaptation techniques, functional results of nerve repair are still inadequate. Potential benefits of developing modified coaptation techniques cannot be disregarded. The authors report a new coaptation technique in which the nerves are cut in an oblique fashion to increase the coaptational surface. The sciatic nerves of male Wistar albino rats were cut at an angle of 30 and 45 deg (experimental groups), and 90 deg (control group). The nerves were repaired with nine 10-0 epineural stitches. Functional and histological studies were performed at week 12 on 7 rats from the 30-deg group, 15 rats from the 45-deg group, and 7 rats from the 90-deg group. Mean sciatic function index values of walking track analysis were the following: 30-deg group, -42.4+/-15.4; 45-deg group, -44.7+/-17.9; and 90-deg group, -52.9+/-13.9 (p>0.05). The mean values of myelinated axonal counts for the 30-deg, 45-deg, and 90-deg transection groups were 196.2+/-3.7, 196.1+/- 3.7, and 176.1+/- 5.6 respectively for proximal nerve segments and 180.1+/-6.8, 178.2+/-3.8, and 114.1+/-17.3 respectively for distal samples. Both the 30-deg and 45-deg coaptational groups had a significantly lower reduction of myelinated axonal counts at the regeneration zone in comparison with the 90-deg group (p<0.01). Mean myelinated axonal diameters in the proximal nerve segments were 8.2+/-2.6 microm, 8.4+/-3.1 microm, and 8.1+/-3.2 microm respectively, and were 7.1+/-3.6 microm, 6.9+/-3.4 microm, and 6.7+/-3.4 microm respectively in the distal nerve segments (p>0.05). The oblique nerve coaptation technique may enhance nerve regeneration by enabling a larger sprouting and contact area for nerve fibers, but additional investigation by more experienced centers is needed before relying on the preliminary results of this simple modification.

Animals↗
PubMed1999

Ultrastructure of the lens epithelium in Alport's syndrome.

The ultrastructure of the lens epithelium in Alport's syndrome was studied. In a transmission electron-microscopic examination, a large number of tonofilaments, swollen mitochondria, a dilated Golgi complex, a dilated rough endoplasmic reticulum with electron-dense (osmiophilic) material in some of these irregular structures and myelin figures were observed. Most of the cells had regularly shaped and only a few of them irregularly shaped nuclei. Additionally, polymorphism and marked degeneration in the transitional zone were observed in the scanning electron-microscopic examination of the lens epithelium. After the transitional zone, there were no epithelial cells present under the lens capsule, an observation that has never been reported in the literature.

Adult↗
PubMed1999

Anatomic study of complex anomalies of the digastric muscle and review of the literature.

The digastric muscles of 99 cadavers were examined bilaterally. In 5 of them, the digastric muscles showed different types of complex abnormalities. These complex anomalies should be kept in mind in functional studies involving the floor of mouth and evaluating the same structures with CT and MR imaging. Secondly, the embryological basis of the isolated anomalies of the anterior digastric muscle with respect to its occurrence together with the mylohyoid muscle stressed in this article needs further studies of their development from the first branchial arch.

Cadaver↗
PubMed1998

Electron microscopic findings of penile tissues in veno-occlusive dysfunction: is penile biopsy necessary?

In this study, we examined the biopsy patterns of penile tissues taken during operation from patients subjected to surgical treatment for veno-occlusive dysfunction, and evaluated the importance of penile biopsy. We evaluated the findings from 17 patients with venous impotence. Fourteen of them underwent total vein ligation and the rest penile prosthesis implantation. Tissue specimens taken from superficial and deep dorsal veins, tunica albuginea and corpus cavernosum during operation were examined under electron microscope. Tissue specimens taken from 3 cadavers were used as the control group. Although the deep and superficial vein specimens of all patients did not show significant differences, oedema and increase of fibroblasts in collagen fibres of the corpus cavernosum and tunica albuginea were demonstrated. We concluded that penile biopsy as an invasive method does not give enough information about the choice of treatment for erectile dysfunction.

Adult↗
PubMed1998

Fine structure of the human coccygeal body: a light and electron microscopic study.

There is only limited data on the microscopic structure of the coccygeal body in classical textbooks. Although there are several articles describing the light microscopic structure of the organ, the data presented are rather conflicting especially when comparing glomus tumors and normal coccygeal bodies. We therefore examined the pericoccygeal soft tissues histologically with the aim of obtaining further evidence. At the light microscopic examination, coccygeal bodies were distinguished as sections of several blood vessels encapsulated by a connective tissue capsule. Small arteries within the coccygeal bodies had an unusual endothelial lining, resembling pseudostratified epithelium or neuro-epithelium. We observed increased numbers of glomus cells in a few samples. A highly tortuous course run by the small arteries was observed in the serial sections. At their electron microscopic examination, endothelial cells exhibited the features of columnar epithelial cells, though some appeared to be vacuole rich. The basal surface of the cells showed basal infoldings, but not as extensive as those of absorptive cells. External lamina, subplasmalemmal vesicles, bundles of microfilaments, groups of membrane bound organelles including mitochondria and endoplasmic reticulum were observed in glomus cells. In conclusion, it is rather difficult to use the term tumor for the coccygeal bodies when relying solely on the number of cells observed, because some segments of the coccygeal bodies were rich in glomus cells. It is more likely that the coccygeal bodies show variability in different individuals. The characteristics of the endothelium of the small arteries in coccygeal bodies needs to be examined in a wider range of specimens in order to be validated as a unique entity.

Actin Cytoskeleton↗
PubMed1998

Early protective effects of Iloprost after experimental spinal cord injury.

This investigation was undertaken to study the early protective effects of Iloprost, a stable analogue of prostacyclin, after spinal cord injury in rabbit. Sixteen adult male rabbits (New Zealand Albino) were injured by application of epidural aneurysm clip. Eight rabbits received an intravenous (i.v.) infusion of 30 micrograms kg-1 Iloprost, and eight rabbits received an infusion of saline (SF). Treatment with Iloprost started immediately after spinal cord injury and continued for one hour. Evoked potentials were recorded for each rabbit at one, 15, and 60 minutes after the spinal cord injury. Twenty-four hours later, all the rabbits were deeply anesthetized and spinal cords were removed for histopathological examinations. There was no meaningful statistical difference between cortical somatosensorial evoked potentials (CSEP) of the saline and Iloprost group. However, light and electron microscopic studies showed that the Iloprost treated group had moderate protection of myelin and axons; and limited edema. These results suggest that intravenous Iloprost treatment after spinal cord injury has a highly protective effect without any side effects.

Animals↗