Biomedical subjects

N Culhaci

Publications and source records attributed to N Culhaci.

8 recordsLinked to original sources

PubMed2003

The interdomal fat pad of the nose: a new anatomical structure.

The nose is one of the most operated organs in the body and its anatomy has been well defined by plastic and ENT surgeons. Although rhinoplasty is the most commonly performed operation in plastic surgery, some unexpected results and complications may be related to unknown or unclarified anatomical structures in the nose. We aimed to evaluate the interdomal region in four fresh cadavers and 24 patients who underwent open rhinoplasty, since the nasal tip area is the most difficult part of the rhinoplasty. Detailed cartilage and soft tissue interactions were studied in fresh cadavers. The existence of the interdomal fat pad as a separate anatomical structure was proven in necropsy specimens from cadavers using various histochemical dyes. Nasal tip ultrasonography was performed preoperatively in patients who underwent rhinoplasty. All patients had a fat pad in the interdomal space, of varying sizes, but fatty (bulbous) noses had larger fat pads. Interdomal fat pad tissue, which occupies the interdomal space, was demonstrated by ultrasonography. The size of the fat pads varied from 1.2 mm x 2.4 mm to 3.6 mm x 5.2 mm. Anatomical observation and biopsies were performed during surgery. Finally, surgical and radiological anatomy of the interdomal fat pad was demonstrated in all cadavers and patients. We speculate that the interdomal fat pad is an important anatomical structure and may contribute to unexpected postoperative results in rhinoplasty. This newly defined fat pad can be assessed by ultrasonography, a safe and inexpensive technique. The surgical approach to the interdomal fat pad is solely through open rhinoplasty technique. Thus, a consideration of the interdomal fat pad and detection of its size preoperatively may play a key role in choice of technique and success of rhinoplasty.

Adipose Tissue↗

PubMed2002

Immunohistochemical findings in notalgia paresthetica.

BACKGROUND: Notalgia paresthetica (NP) is a sensory neuropathy the pathogenesis of which is not yet completely elucidated. OBJECTIVE: The aim of this study was to investigate the histopathological changes in NP with special emphasis on cutaneous innervation. METHODS: Along with site-matched biopsies from 5 healthy individuals, lesional skin biopsies from 14 cases of NP and biopsies from contralateral nonlesional skin in 9 of these cases were stained with hematoxylin-eosin and Congo red. For immunohistochemical analysis, all samples were stained with two general neural markers (S-100 protein and protein gene product 9.5) and two neuropeptides (vasoactive intestinal polypeptide and substance P). RESULTS: Light microscopy was compatible with postinflammatory hyperpigmentation. Immunohistochemistry did not reveal a significant difference in the staining pattern of lesional skin and control tissue (p > 0.05). Although not reaching statistical significance, the percentage of cases which showed no staining was higher in the group of patients with more chronic NP. CONCLUSION: The finding of less immunohistochemical staining in cases with more chronicity could be of clinical importance and is worth investigating further.

Adult↗

PubMed2001

A new experimental model for cryptorchidism: inguinoscrotal approach.

We investigated the effect of inguinal canal closure as a new mechanically induced cryptorchid rat model. The effectiveness of this new model was evaluated by histopathological examination. Thirty-one 21-day-old Wistar rats were divided into four groups. In groups 1 (n = 6), 2 (n = 6) and 3 (n = 7), unilateral undescended testis was created by performing inguinal canal closure with inguinoscrotal approach. Sham-operated rats were used as controls in group 4 (n = 12). The rats were killed on day 30 after surgery in group 1, day 45 in group 2 and day 60 in group 3. The seminiferous tubular diameter, number of tubules with mature germ cell and Leydig cell clusters were evaluated. None of the rats were lost during the study period. Signs of infection were not detected in operation site although antibiotics were not used. Overall only three (16%) testes descended into scrotum in study groups. The operation time was 3-4 min for each rat. Histopathological examination revealed detrimental effects of cryptorchidism on testicular growth in study groups. In all groups, except the sham group, the mean tubular diameter and the number of tubules with mature germ cells in the left testicle were significantly decreased compared to the right ones. Our findings were in correlation with other experimental studies using different rat models of cryptorchidism. This new model of cryptorchidism is considered to provide a simple and effective technique for investigating the impaired development of the testes in cryptorchidism.

Animals↗

PubMed2001

Quantification of tumor cellularity and mitotic index in invasive ductal carcinoma of the breast.

OBJECTIVE: To evaluate the use of stereologically estimated tumor cell counts in the mitotic index as well as to investigate its correlation with the currently used method and test the reproducibility of the method. STUDY DESIGN: The stereologic method described by Simpson et al was used to estimate tumor cellularity in 50 invasive ductal carcinomas. Mitotic counts were also performed, and the mitotic index was calculated by the use of estimated tumor cell counts. Estimated cell counts and the mitotic index calculated were compared statistically with the actual cell counts and the traditional mitotic grades, respectively. Interobserver reproducibility of the method was also tested. RESULTS: Stereologically estimated tumor cell counts had a good correlation with actual cell counts (r = .891, P < .001). Besides, the mitotic indices calculated with tumor cell counts (calculated with both estimated and actual cell counts) in the denominator of the fraction of the mitotic index were in agreement with the currently used method (P < .01 for both). There was no statistically significant difference between the counts of two observers (P = .068). CONCLUSION: The suggested method, considering tumor cellularity as an influencing factor, was practical, reproducible and in agreement with the traditional method. This method should be studied in a large group of patients with follow-up data to determine the threshold values for different grades and determine its prognostic value during the disease course.

Breast Neoplasms↗

PubMed2001

Epididymal changes associated with cryptorchidism in rats.

AIM: To investigate the effect of a new mechanically induced cryptorchidism model on rat epididymal histology. METHODS: Eighteen 21-day-old Sprague Dawley rats were randomly divided into 3 groups of 6 animals each. Animals of Groups 1 and 2 were made unilaterally cryptorchid by closing the left inguinal canal, while Group 3 (controls), sham operated. At Day 60 (Group 1) and Day 90 (Group 2 and 3), the rats were sacrificed. The epididymides of both sides were weighed, and the diameter of the epididymal tubules, the height of the tubular epithelium and the presence of fibrosis of the caput epididymides were examined under a light-microscope. RESULTS: The cryptorchid epididymis had a significantly lower weight increase than the contralateral ones and the controls, but the epithelial height and diameter of caput epididymal tubules were not significantly different. Fibrosis was not observed. CONCLUSION: The authors proposed that this new model is a convenient method to evaluate the epididymal changes associated with experimental cryptorchidism.

Animals↗

PubMed2000

Notalgia paresthetica: a study on pathogenesis.

BACKGROUND: Notalgia paresthetica is a sensory neuropathy involving the dorsal spinal nerves. The characteristic symptom is pruritus on the back, occasionally accompanied by pain, paresthesia, and/or hyperesthesia, which results in a well-circumscribed hyperpigmented patch in the symptomatic area. The etiology of this condition has not yet been completely defined. OBJECTIVE: Possible mechanisms that could explain the pathogenesis of notalgia paresthetica were investigated through clinical examination and various diagnostic tests. METHODS: Ten cases of notalgia paresthetica underwent dermatologic, neurologic, and orthopedic examination. This was followed by skin biopsy, electrodiagnostic investigation, and radiography of the spine. RESULTS: All patients had a typical symptomatology and dermatologic picture. Neurologic examination and standard electrodiagnostic investigation results were normal in all cases. Histopathology was compatible with postinflammatory hyperpigmentation; there were no amyloid deposits. In seven cases, degenerative changes in the vertebrae were observed and, in all of these cases, these changes were most prominent in the vertebrae which corresponded to the dermatome of the cutaneous lesion. CONCLUSIONS: The striking correlation of notalgia paresthetica localization with degenerative changes in the spine suggests that spinal nerve impingement may contribute to the pathogenesis of this entity.

Adult↗

PubMedDate not supplied

Is synchronous bowel anastomosis safe?

In this study, we investigated the effects of synchronous anastomosis on intestinal healing in experimental colonic resection. Sprague-Dawley rats were randomized into 3 groups; control (group I), single anastomosis (group II) and synchronous (double) anastomosis (group III). Single and proximal anastomoses were located 3 cm distal to caecum, and distal anastomoses were done 3 cm distal to them. On the 7th postoperative day, bursting pressure, hydroxyproline level and histology of the anastomotic site were assessed. Bursting pressures and hydroxyproline levels indicated that impaired healing of proximal anastomoses in group III was evident. Proximal anastomoses in group III had the lowest hydroxyproline value and bursting pressure level. Significant fibrosis was observed in the histological examination of distal anastomoses in group III. Double colonic anastomoses is not as safe as single anastomoses and involves additional risk. The healing of proximal anastomosis is significantly altered after experimental synchronous resection.

Anastomosis, Surgical↗

PubMedDate not supplied

The effects of nitric oxide supplementation and inhibition on bacterial translocation in bile duct ligated rats.

Obstructive jaundice promotes bacterial translocation from the gut, but the role of nitric oxide is controversial in this process. We studied the effects of nitric oxide synthase substrate, L-arginine, and nitric oxide synthase inhibitor, N(G)-nitro-L-arginine methyl ester, on bacterial translocation in bile duct ligated rats. The animals were randomized into five groups; control, sham, common bile duct ligation alone, nitric oxide inhibition, and nitric oxide supplementation. Obstructive jaundice was performed with common bile duct ligation. L-arginine or N(G)-nitro-L-arginine methyl ester was injected once daily for 14 days. Blood bilirubin level, liver histology, and bacterial translocation to the mesenteric lymph nodes as well as to the liver were assessed. The L-arginine supplemented group had the lowest bacterial translocation rate, but the most prominent hepatic fibrosis. Nitric oxide inhibition increased bacterial translocation to the mesenteric lymph nodes. Therefore, the administration of nitric oxide donor or inhibitor acts as a significant regulatory factor for bacterial translocation in obstructive jaundice.

Analysis of Variance↗