Blunt trauma induced closed femoral bone fracture in a Rat model: are vessels safe to use for microsurgery? Further insight into the zone of injury concept

BACKGROUND

The study aims to investigate the zone of injury for major vessels after high-velocity traumas, as it is unclear whether avoiding vascular structures is necessary during microvascular anastomosis or how long it takes for them to be used again.

METHODS

This study uses Doppler ultrasonography and a rat model to evaluate the histopathological changes and flow velocity of major vessels in the zone of injury after high-velocity trauma with closed femoral bone fracture. Osteosynthesis was performed using an intramedullary wire. Samples were collected from day 3 and week 3. The unaffected contralateral side is used as control.

RESULTS

Results from arterial and venous flow assessments showed no evidence of ischemia in the extremities. Both arteries and veins were patent in both intervals and on the control side. The evaluation of the vessels showed arterial injury with a slightly reduced arterial flow on Day 3 and Week 3. The venous flow was slightly reduced on Day 3 but not on Week 3. Statistically, arterial endothelial injury was higher on day 3 than on week 3 (p = 0.006). Media inflammation was also higher on day 3 (p = 0.06). Arterial endothelization distribution was higher in week 3 (p = 0.006). No significant differences were found in arterial media irregularity, necrosis, platelet aggregation, bleeding, and wall rupture. Venous samples showed no significant differences in any parameter (p < 0.05).

CONCLUSION

High-velocity trauma increases the risk of thrombosis in vessels. Intravascular repair can start on day 2 and continue till week 3 with significant endothelization. Although physiologic findings do not alter arterial or venous flow, histologic findings support vessel injuries leading to potential complications. Microsurgery should be considered out of the injury zone until adequate vessel healing is achieved.

Dermoscopy of Pilonidal Cyst Disease: A Case-series

Dear Editor, Pilonidal cyst disease is a common, acquired, inflammatory disease predominantly affecting the natal clefts of the buttocks (1,2). The disease has a predilection for men, with a male-to-female ratio of 3-4:1. Patients are generally young, towards the end of second decade of life. Lesions are initially asymptomatic, while the development of complications such as abscess formation is associated with pain and discharge (1). Patients with pilonidal cyst disease may present to dermatology outpatient clinics, especially when the disease is asymptomatic. Herein we report the dermoscopic features of four cases of pilonidal cyst disease encountered in our dermatology outpatient clinic. Four patients who presented to our dermatology outpatient department for evaluation of a solitary lesion on buttocks were diagnosed with pilonidal cyst disease based on clinical and histopathological examination. All patients were young men and presented with solitary, firm, pink, nodular lesions in the region in proximity to the gluteal cleft (Figure 1, a, c, e). Dermoscopy of the first patient revealed a red structureless area in the central part of the lesion, consistent with ulceration. Additionally, white lines reticular as well as glomerular vessels were present at the periphery on the pink homogenous background (Figure 1, b). In the second patient, a yellow structureless central ulcerated area was surrounded by linearly arranged multiple dotted vessels at the periphery on a homogenous pink background (Figure 1, d). In the third patient, dermoscopy revealed a central yellowish structureless area with peripherally arranged hairpin and glomerular vessels (Figure 1, f). Lastly, similar to the third case, dermoscopic examination of the fourth patient showed a pink homogenous background with yellow and white structureless areas and peripherally arranged hairpin and glomerular vessels (Figure 2). Demographics and clinical features of the four patients are summarized in Table 1. Histopathology of all our cases revealed epidermal invagination and sinus formation, free hair shafts, and chronic inflammation with multinuclear giant cells. Histopathological slides of the first case can be seen in Figure 3 (a-b). All patients were referred to general surgery for treatment. The current knowledge pertaining to dermoscopy of pilonidal cyst disease is scarce in the dermatologic literature, and was previously evaluated in only two cases. Similar to our cases, the authors reported the presence of a pink-colored background, radial white lines, central ulceration, and multiple peripherally arranged dotted vessels (3). The dermoscopic features of pilonidal cysts differ from other epithelial cysts and sinuses. As for epidermal cysts, the presence of punctum and an ivory-white background color have been reported as characteristic dermoscopic findings (4,5). In addition, unruptured epidermal cysts reveal arborizing telangiectasia, while the ruptured epidermal cysts show peripheral linear branched vessels (4,5). A peripheral brown rim, linear vessels, and yellow homogenous background of the entire lesion have been reported as dermoscopic features of steatocystoma multiplex as well as milias (5). Of note, other cystic lesions mentioned above are typified by linear vessels, whereas pilonidal cysts present dotted, glomerular, and hairpin vessels. Pilonidal cyst disease must also be considered in the differential diagnosis of pink nodular lesions, along with amelanotic melanoma, basal cell carcinoma, squamous cell carcinoma, pyogenic granuloma, lymphoma, and pseudolymphoma (3). Based on our cases and the two cases in the literature, pink background, central ulceration, peripherally arranged dotted vessels, and white lines seem to be common dermoscopic features of pilonidal cyst disease. Our observations demonstrate that central yellowish structureless areas along with peripheral hairpin and glomerular vessels are also among the dermoscopic features of pilonidal cyst disease. In conclusion, pilonidal cysts can be easily differentiated from other skin tumors by the aforementioned dermoscopic features, and the diagnosis in patients clinically suspected of having pilonidal cyst can be supported by dermoscopy. However, there is need for further studies in order to better characterize typical dermoscopic features of this disease and their frequency.

The effect of fibrin clot and C vitamin on the surgical treatment of Achilles tendon injury in the rat model✰

BACKGROUND

This study aimed to determine the histological, biochemical, and biomechanical efficacy of fibrin clot and vitamin C in the healing of Achilles tendon ruptures (ATR) in a rat model.

METHODS

52 adult Wistar-Albino rats (300-450 g) were used in the study. 12 rats were divided into four groups as Monitor (Group I), Control (Group II), Fibrin Clot (Group III), Fibrin Clot with vitamin C (Group IV). Four rats were used for fibrin clot preparation. Fibroblast Growth Factor (FGF) and Vascular Endothelial Growth Factor (VEGF) were measured on the 3rd, 7th, 14th, and 21st days. Four rats were sacrificed on the 21st day from each group for histological evaluation. The rest of the rats were sacrificed at 42nd day, half for biomechanical and a half for histological evaluation.

RESULTS

The 42nd-day HSS score of group IV was significantly lower than those of group I, group II and group III (p = 0.036, p = 0.019, and p = 0.036, respectively). Group IV showed a significantly higher Maximum force N value than those of group I, group II and group III (p = 0.034, p = 0.034 and, p = 0.025, respectively). The blood FGF and VEGF levels of group III and group IV on the 3rd, 7th, 14th, and 21st days were higher than those of group I and group II (p < 0.05).

CONCLUSION

Fibrin clot and vitamin C produced a stronger tendon structure in terms of biomechanics while providing histological and biochemically better quality tendon healing in the surgical treatment of ATR. This model can be used to accelerate high-quality tendon healing after ATR.

LEVEL OF EVIDENCE

Level II, experimental study.

Effects of Quetiapine on Neural Tube Development in the Early Stage of Chicken Embryos

AIM

To investigate the effects of quetiapine exposure on neural tube development in early stage chicken embryos.

MATERIAL AND METHODS

Eighty-four fertilised specific pathogen-free chicken eggs were divided into four equal groups (groups 1?4). Three experimental groups (groups 2, 3 and 4) and a single control group (group 1) were used. Each egg in group 2 (n=21) was injected with 20 ?L of saline after 30 hours of incubation. Eggs in groups 3 and 4 were injected with 0.02 ml of a solution containing 400 and 800 ?g of quetiapine dose, respectively. Incubation was continued until the end of 72 hours. All embryos were then removed from the eggs and histopathologically examined.

RESULTS

Normal development and the closed neural tubes were shown in 18, 16, 13 and 9 embryos in groups 1 2, 3 and 9, respectively, of the 84 embryos incubated. Open neural tubes were found in one, three and five embryos in groups 2, 3 and 5, respectively. Also, developmental anomalies were found in three, four, five and seven embryos in groups 1, 2, 3 and 4, respectively. Moreover, no significant relationship between NTD and quetiapine exposure had been found.

CONCLUSION

Quetiapine has no significant effect on the occurrence of neural tube defects in the chicken embryo model.

Dermoscopic findings in a case of multiple subungual fibromas

Periungual and subungual fibromas, also known as Koenen tumors, are diagnostic findings of tuberous sclerosis. The clinical appearance and histological features that characterize ungual fibromas are well defined. However, dermoscopic findings of these benign tumors have not been reported previously. Here we report a rare presentation of multiple subungual fibromas of all fingers in a developmentally delayed patient with tuberous sclerosis along with the dermoscopic features of the ungual tumors.

Effects of Tartrazine on Neural Tube Development in the Early Stage of Chicken Embryos

AIM

To investigate the effects of tartrazine exposure on neural tube development, in early stage chicken embryos.

MATERIAL AND METHODS

A total of 120 fertilized specific pathogen-free chicken eggs were divided into 4 equal groups (groups 1?4). After 30 hours of incubation, the eggs, except for the Group 1 (control group), were opened under 4X optical magnification. Group 2 was administered physiological saline. Group 3 was administered a middle dose of tartrazin (4.5 mg/kg) at a volume of 20 µL by the in ovo method, and group 4 was administered a high dose of tartrazine (7.5 mg/kg) using the same process. Incubation was continued until the end of the 72nd hour; all embryos were then removed from the eggs and histopathologically examined.

RESULTS

Of the 120 embryos incubated, normal development and the closed neural tubes were shown in all embryos in group 1; 23 in group 2; 19 in group 3 and; only 9 in group 4. Open neural tubes were found in; 4 embryos in group 2; 5 embryos in group 3 and; 13 embryos in group 4. The neural tube closure defect was found to be significantly higher in group 4 compared to the other groups (p < 0.01).

CONCLUSION

Based on our data, tartrazine, as one of the widely used food coloring agent, was seen to cause a neural tube defect in the chicken embryo model.

Alendronate induced subacute cutaneous lupus erythematosus successfully treated with intravenous immunoglobulin

The subacute cutaneous lupus erythematosus (SCLE) is a distinct subtype of lupus erythematosus (LE) representing specific clinical and serological features. Almost 20%-30% of the cases with SCLE are predicted to associated with medications. Thiazide diuretics, terbinafine, antiepileptic, and proton pump inhibitors are the best-known drugs to induce drug-related SCLE. Herein we want to present a 65-year-old female with alendronate induced SCLE, resistant to classical therapies, and respond well to intravenous immunoglobulin (IVIG), suggesting that IVIG could be an alternative treatment in patients resistant to classical treatment protocols.

Reticulin staining pattern in the differential diagnosis of benign parathyroid lesions

AIM

A reticulin staining pattern (RSP) can be used for the differential diagnosis of endocrine gland lesions, as in the adrenal and hypophysis glands. We aimed to use RSP for the differential diagnosis of parathyroid gland lesions.

MATERIALS AND METHODS

In this study, we evaluated 97 parathyroid lesions in 85 patients, as well as 29 normal parathyroid glands. All sections were stained with a silver impregnation-based kit for the reticulin stain. The RSPs were classified as short thick fiber-, anastomosing- and nodular/alveolar-pattern. The dominant pattern was accepted as being greater than 50% in each section.

RESULTS

Short thick fibers and anastomosing and nodular RSPs were seen in adenomas, but there was no alveolar pattern. Although nodular/alveolar patterns were seen in focal areas in hyperplasia, they never became the dominant pattern. Nodular dominant RSPs were seen in adenomas; however, nodular RSPs were not seen in hyperplasia in a dominant pattern (p = 0.049). While short thick fibers were not seen in normal glands, they could be seen in adenomas (p < 0.001) and in hyperplasia (p < 0.001).

CONCLUSION

RSPs can be used in the differential diagnosis of parathyroid lesions. While short thick reticular fibers support adenomas and hyperplasia rather than normal tissue, a nodular dominant pattern supports adenomas rather than hyperplasia.

Multinodular and vacuolating neuronal tumor of the cerebrum: Two cases and review of the literature

BACKGROUND

Multinodular and vacuolating neuronal tumor (MVNT) recently described as a purely neuronal tumor. Although its nature as a genuine tumor is controversial, this new entity assumed benign lesion and mostly affecting adults. Herein, we introduce two cases of MVNT presumed low grade glial tumor (LGG) and focal cortical dyplasia (FCD) as a differential diagnosis.

CASE DESCRIPTION

Case 1 has admitted to our hospital with headache which frequency and severity has increased within two months. Radiological examination revealed hyperintensity on T2-WI and T2 FLAIR images. Microsurgical resection was performed and histopathological findings were compatible with MVNT instead of low grade glial tumor as we thought. Case 2, who presented at our hospital with one episode seizure. MRI showed T2 hyperintensity and T1 hypointensity without contrast enhancement. We suspected FCD, thus performed microsurgical gross total resection with frontal craniotomy. Pathological findings confirmed MVNT as a diagnosis. Both cases were discharged on the 3rd day after surgery without any complications and with no regrowth of tumor at the 9-months and 3-months follow-up respectively.

CONCLUSIONS

Radiological hallmarks may be helpful to prevent from aggressive treatment in case of patient is asemptomatic. Nevertheless further studies are necessary for the adoption of 'wait and see' philosophy and give a verdict about benign nature of these tumors.

The Effects of Mucoperichondrial Flap Elevation on Septal L-Strut Cartilage: A Biomechanical and Histologic Analysis in a Rabbit Model

BACKGROUND

The harvesting of septal cartilage following mucoperichondrial flap elevation has almost become a standard step in rhinoplasty. However, the strength of the remaining septum has not yet been evaluated. In the current experimental study of a rabbit rhinoplasty model, the remaining septum following a graft harvest was analyzed both biomechanically and pathologically.

METHODS

Forty New Zealand rabbits were classified into four equal groups. Group 1 consisted of the animals in which unilateral elevation of the mucoperichondrial flaps was undertaken before the graft harvest, group 2 consisted of the animals in which bilateral elevation was undertaken, group 3 included the animals where the septum was exposed and left untouched after a bilateral mucosal flap elevation, and group 4 was designated as the control group. Specimens were analyzed under light microscopy for multiple parameters. Biomechanical analyses were performed with a universal testing device at the Department of Engineering, Biomechanical Laboratories, Istanbul Technical University.

RESULTS

Biomechanical analysis in terms of maximum tension revealed significant results among the groups (p = 0.008). Although insignificant results were observed overall using a pathologic analysis, the amount of chondrocytes was lower in group 2 than in group 1 (p = 0.099). The amounts of matrix collagen (p = 0.184) and fibrosis were (p = 0.749) higher in group 2 than in group 1.

CONCLUSIONS

From these data, the authors conclude that mucoperichondrium integrity plays a crucial role in the biomechanical strength of the septum. More sophisticated studies with further pathologic analysis are required to determine the exact mechanism of strength loss observed with mucoperichondrial flap elevation.

Is testis-sparing surgery safe in small testicular masses? Results of a multicentre study

INTRODUCTION

Our goal was to evaluate benign and malignant lesions and testicular intraepithelial neoplasia (TIN) in the neighbouring normal-appearing testis tissue in men who underwent radical orchiectomy for testicular mass with a pathologic tumour size of ≤3cm.

METHODS

In this retrospective, multicentre study, data of 252 patients from 11 different institutions were included. Patients were divided into three groups based on tumour size: Group 1 (0-1 cm; n=35), Group 2 (1.1-2cm; n=99), and Group 3 (2.1-3 cm; n=118). Benign lesions and TIN were sought in the neighbouring testicular tissue and compared between groups.

RESULTS

Mean patient age was 32.3 years. Benign lesions were reported in 54.3%, 33.3%, and 14.4% of Groups 1, 2, and 3, respectively (p<0.05 between groups). TIN was detected in 20%, 42.4%, and 41.5% of Groups 1, 2, and 3, respectively (p<0.05 for Group 1 vs. Groups 2 and 3; p>0.05 for Groups 2 vs. 3). Multifocality was detected in 8.6%, 4%, and 0% of Groups 1, 2, and 3, respectively (p<0.05 for both Group 1 vs. Group 3 and for Group 2 vs. Group 3; p>0.05 for Group 1 vs. Group 2). A tumour cutoff size of 1.5 cm was found to be significant for detecting benign tumour. TIN and multifocality rates were similar in patients with a tumour size of ≤1.5 vs. >1.5 cm (p>0.05).

CONCLUSIONS

Benign lesions and TIN in the neighbouring testis were significantly decreased and multifocality was increased in patients with a tumour mass size of ≤1 cm. Testis-sparing surgery should be performed with caution and a safety rim of normal tissue should also be excised.

Quantitative Assessment of Steroid Hormone Binding Sites by Thaw-Mount Autoradiography,

A procedure for the quantitative assessment of nuclear receptors for steroid hormones—and other substances—in individual cells is presented. Thaw-mount autoradiography, a procedure developed earlier in our laboratory, is utilized. The silver grain yield (specific activity) is 16.6 disintegrations per silver grain as determined for tritium in guinea pig uterine tissues. An integrated formula is presented and applied for 3H-estradioI, 3H-diethyl-stilbestrol, and 3H-aldosterone in sampled tissues. A comparison with data derived from the literature that are based on the homogenization of whole uteri and biochemical analysis shows comparable values with the autoradiographic data if the latter are pooled. The pooled data indicate 12–14,000 molecules of 3H-estradiol per uterine nucleus, while subpopulations of target cells vary between 5,000 and 28,000 per nucleus.

[Perineural dexmedetomidine effects on sciatic nerve in rat]

The present study was designed to test the hypothesis that high dose dexmedetomidine would increase the duration of antinociception to a thermal stimulus in a rat model of sciatic nerve blockade without causing nerve damage. The rats were anesthetized with isoflurane. After electromyography (EMG) recordings, right sciatic nerves were explored and perineural injections were delivered: Group D (n=7), 40μgμgkg^-1 dexmedetomidine administration, Group II (n=6), (0.2mL) saline administration, Group III (n=2), only surgically exploration of the right sciatic nevre. Time to paw withdrawal latency (PAW) to a thermal stimulus for both paws and an assessment of motor function were measured every 30min after the nerve block until a return to baseline. The compound muscle action potential (CMAP) of right and left sciatic nerves were recorded 10 times per each nerve once more after perineural injections at 14 day. After EMG recordings, right and the part of left sciatic nerve were excised at a length of at minimum 15mm for histopathological examination. Comparison of right/left CMAP amplitude ratios before and 14 days after the procedure showed a statistically significant difference (p=0.000). There were no differences in perineural inflammation between the Group D, Group S, and Group E at 14 days.

The First Successful Case of Transoral Robotic Surgery in a Patient with Sialadenoma Papilliferum

INTRODUCTION

Sialadenoma papilliferum (SP) is a rare benign tumor, which originates from the minor salivary gland. It occurs at sites that have minor salivary glands, such as the palate, retromolar pads, buccal mucosa, and lips. The most common location for tumor development is on the hard palate. A differential diagnosis consists of ruling out other salivary gland tumors. Transoral robotic surgery (TORS) is a new technology used in head and neck surgery within certain centers around the world.

CASE REPORT

Herein, we present the first successful case of SP tumor removal by TORS.

CONCLUSION

This particular case highlights the identification of this rare tumor in an unusual location. Furthermore, it demonstrates the utilization of TORS, leveraging the superior visualization to obtain excellent local control with minimal acute and long-term morbidity, in comparison to conventional transoral surgical approaches.

Perineural dexmedetomidine effects on sciatic nerve in rat

The present study was designed to test the hypothesis that high dose dexmedetomidine would increase the duration of antinociception to a thermal stimulus in a rat model of sciatic nerve blockade without causing nerve damage. The rats were anesthetized with isoflurane. After electromyography (EMG) recordings, right sciatic nerves were explored and perineural injections were delivered: Group D (n=7), 40μgμgkg^-1 dexmedetomidine administration, Group II (n=6), (0.2mL) saline administration, Group III (n=2), only surgically exploration of the right sciatic nevre. Time to paw withdrawal latency (PAW) to a thermal stimulus for both paws and an assessment of motor function were measured every 30min after the nerve block until a return to baseline. The compound muscle action potential (CMAP) of right and left sciatic nerves were recorded 10 times per each nerve once more after perineural injections at 14 day. After EMG recordings, right and the part of left sciatic nerve were excised at a length of at minimum 15mm for histopathological examination. Comparison of right/left CMAP amplitude ratios before and 14 days after the procedure showed a statistically significant difference (p=0.000). There were no differences in perineural inflammation between the Group D, Group S, and Group E at 14 days.

Surgical Treatment in a Case of Cogan's Syndrome Complicated With Proximal Aortic Vasculitis

Cogan's syndrome is a rare idiopathic inflammatory disease with involvement of the eye and inner ear. This syndrome can be associated with aortic root vasculitis. We report the case of a young man with a history of uveitis and bilateral hearing loss who presented with proximal aortic vasculitis and dilatation after aortic valve replacement. Cogan's syndrome was diagnosed on the basis of large artery vasculitis with typical vestibuloauditory and ocular involvement. The patient underwent successful a Bentall operation after aortic valve replacement.

Histopathological diversity in parotidectomy materials in Turkish population: clinicopathologic analysis and demographic features of 136 cases in a tertiary care hospital

BACKGROUND

Salivary gland tumours, which account for approximately 3% of head-neck cancers, are a heterogeneous group and thus it is difficult to identify their epidemiological characteristics. The aim of this study is to determine demographic features and histopathologic distribution of parotid neoplasms in a large sample from Turkey.

MATERIALS AND METHODS

This study was conducted retrospectively on 136 parotidectomy materials from operations between May 2009-May 2013. Age, gender, tumor diameter, histopathological diagnosis and surgical margin status were recorded.

RESULTS

The benign cases were 112 (82.4%), while the malignancies were 24 (17.6%). The accuracy rate of FNAC was 91%. There were 46 (33.8%) male and 90 (66.2%) female patients. Female/ male ratio (M/F=0.5) was two, the Warthin (WT) tumor being more apparent in males (p<0.05). Pleomorphic adenoma (PA) was detected most frequently among benign pathologies at 61.6% (69/112), while the Warthin Tumor (WT) was detected as the second most frequent tumor at 20.5% (23/112). Mucoepidermoid carcinoma (MEC) and carcinoma ex pleomorphic adenoma (Ca ex PA) were detected at equal frequency at 20.8% (5/24) among malign tumors. These were followed by acinic cell carcinoma at 16.7% (4/24). While the surgical margin was positive in ten patients with malignant tumors (41.7%), all of the benign tumors were negative (p<0.01). No significant difference was detected in the age-gender of patients, tumor size and distribution of sites among benign and malignant groups (p>0.05).

CONCLUSIONS

Pleomorphic adenoma is the most frequently reported benign tumor almost in all global literature. Yet, the distribution of malignant tumors displays geographical differences. Based on these data, we believe that our findings will provide a significant contribution to future epidemiological studies. We think that it will be beneficial to generate awareness on parotid tumors and ensure a fight against smoking as with all head-neck cancers.

Paricalcitol counteracts the increased contrast induced nephropathy caused by renin-angiotensin-aldosterone system blockade therapy in a rat model

OBJECTIVE

The effect of vitamin D and renin-angiotensin-aldosterone system blockade medications in pathophysiology of contrast induced nephropathy (CIN) is controversial. The effects of paricalcitol (active vitamin D analogue) and losartan treatments in an experimental model of CIN were investigated in this study.

MATERIALS AND METHODS

Thirty-six male Wistar albino rats were examined in five treatment groups. Placebo group (Group A; n = 4) received no active medication; control group (Group B; n = 8) received only contrast media (CM); Group C (n = 8) received paricalcitol; Group D (n = 8) received losartan and Group E (n = 8) received paricalcitol plus losartan. CIN was induced by NG-nitro-L-arginine methyl ester and indomethacin before iohexol injection. Renal histopathological findings were categorized and renal immunohistochemical examinations by caspase-3 rabbit primary antibody were performed.

RESULTS

Creatinine and cystatin C levels significantly increased in the treatment groups, compared to Group A. However, creatinine levels were not significantly increased in Groups C, D and E compared to Group B. Compared to Group B, a significant increase of cystatin C levels was observed in Group D (p < 0.01). In Group E, when paricalcitol treatment was added to losartan treatment, cystatin C levels were similar to Group B (p = 1.00). In histopathological and immunohistochemical examination frequency of Grade 2/3 tubular necrosis and renal caspase 3 activity scores were significantly higher in the losartan treatment group compared to the other treatment groups. The histopathological effects related to losartan treatment were found to be reversed when paricalcitol treatment was combined.

CONCLUSIONS

Our findings suggest that paricalcitol treatment counteracts increased contrast induced nephropathy caused by losartan. These findings warrant further clinical studies to investigate the benefit of paricalcitol in CIN prophylaxis.

Maxillary sinus nonodontogenic myxoma extending into the sphenoid sinus and pterygopalatine fossa: case report

Myxomas are benign mesenchymal tumors of uncertain etiology. They can arise from odontogenic tissue, as well as from the sinonasal tract and from the facial and temporal bones, apparently from nonodontogenic mesenchyme. Although histologically benign, myxomas are locally invasive. Histopathology demonstrates a characteristically hypocellular lesion with loose stellate cells. We describe the case of a 48-year-old woman with a nonodontogenic maxillary sinus myxoma that invaded the sphenoid sinus and pterygopalatine fossa. We removed the mass via a combined endoscopic and gingivobuccal approach. The rarity of a nonodontogenic sinonasal myxoma extending into the sphenoid sinus and pterygopalatine fossa is the basis for our presentation of this case.

MMP-2, TIMP-2 and CD44v6 Expression in Non-small-cell Lung Carcinomas

Introduction: Factors that emerge as crucial participants in tumour invasion and metastases are matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinase (TIMP) inhibitors and cellular adhesion molecules (CD44 and similar molecules). They play important roles in tumour invasion and metastasis in non-small-cell lung carcinomas (NSCLCs). Materials and Methods: The study was performed using the data of 33 patients. MMP-2 from the metalloproteinase family, TIMP-2 from the metalloproteinase inhibitor family and the adhesion molecule CD44v6 expression were investigated immunohistochemically to search their role in the metastasis and the clinical outcome of the patients with NSCLCs. Results: Twenty-three tumours (70%) were squamous cell carcinoma (SCC), 9 (27%) were adenocarcinoma (AC), and 1 (3%) was large cell carcinoma (LCC). MMP-2 and TIMP-2 were expressed in high rates in NSCLC but CD44v6 expression was about 50%. Lymphatic invasion was less frequent in TIMP-2-positive patients and this difference was statistically significant (P = 0.005). There was a statistically significant difference between SCCs and ACs with respect to CD44v6 tumoral expression (P = 0.004). Also, there was a negative correlation between lymphatic invasion and the extent of CD44v6; lymphatic invasion was significantly less in CD44v6-positive cases (P = 0.013). Conclusion: We found that TIMP-2 and CD44v6 can decrease the lymphatic invasion in NSCLCs. Also there was observed histiotype-related pattern of CD44v6 variant expression in SCCs. Key words: Immunohistochemistry, Metastasis, Pulmonary neoplasms

MMP-2, TIMP-2 and CD44v6 expression in non-small-cell lung carcinomas

INTRODUCTION

Factors that emerge as crucial participants in tumour invasion and metastases are matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinase (TIMP) inhibitors and cellular adhesion molecules (CD44 and similar molecules). They play important roles in tumour invasion and metastasis in non-small-cell lung carcinomas (NSCLCs).

MATERIALS AND METHODS

The study was performed using the data of 33 patients. MMP-2 from the metalloproteinase family, TIMP-2 from the metalloproteinase inhibitor family and the adhesion molecule CD44v6 expression were investigated immunohistochemically to search their role in the metastasis and the clinical outcome of the patients with NSCLCs.

RESULTS

Twenty-three tumours (70%) were squamous cell carcinoma (SCC), 9 (27%) were adenocarcinoma (AC), and 1 (3%) was large cell carcinoma (LCC). MMP-2 and TIMP-2 were expressed in high rates in NSCLC but CD44v6 expression was about 50%. Lymphatic invasion was less frequent in TIMP-2- positive patients and this difference was statistically significant (P = 0.005). There was a statistically significant difference between SCCs and ACs with respect to CD44v6 tumoral expression (P = 0.004). Also, there was a negative correlation between lymphatic invasion and the extent of CD44v6; lymphatic invasion was significantly less in CD44v6-positive cases (P = 0.013).

CONCLUSION

We found that TIMP-2 and CD44v6 can decrease the lymphatic invasion in NSCLCs. Also there was observed histiotype-related pattern of CD44v6 variant expression in SCCs.

Altered cyclin D1 genotype distribution in human sporadic pituitary adenomas

BACKGROUND

The cyclin D1 gene (CCND1) is a proto-oncogene playing a critical role in the transition through the G1 to the S phase of the cell cycle and is overexpressed in many tumors. G870A polymorphism at the exon4/intron4 splicing region of the CCND1 gene may play a role in pituitary tumorigenesis and invasiveness. The objective of this study was to examine CCND1 polymorphism in patients with different types of sporadic pituitary adenomas.

MATERIAL/METHODS

One hundred thirty patients (38 male, 92 female, mean age: 45.37+/-13.55 SD years) with sporadic pituitary adenomas (PA group) and 129 healthy controls (HC group) were included in the study. The CCND1 G870A polymorphism in PA and HC were genotyped by PCR-RFLP using peripheral blood samples. CCND1 expression was also evaluated with an immunohistochemical method in tumor tissues of 39 patients of the PA group.

RESULTS

The genotype distribution in the PA [AA: 30 (23.1%), AG: 90 (69.2%), GG: 10 (7.7%)] was statistically different from the HC group [AA: 36 (27.9%), AG: 64 (49.6%), GG: 29 (22.5%), p=0.001]. Patients carrying the AG genotype were more frequent compared with the control group. Tumor type, volume, and invasion were not related to the genotype. Immunohistochemically, 21 of the 39 tumors showed nuclear positivity for CCND1, varying between 1 and 40% of tumor cells. Positive staining was observed more intense in patients carrying the AG genotype.

CONCLUSIONS

CCND1 polymorphism may be an early event in tumorigenesis, but it is not a reliable prognostic criterion.

Expression and cellular distribution of multidrug resistance-related proteins in patients with focal cortical dysplasia

Recent arouse of interest indicated that drug resistant proteins are markedly over-expressed in the epileptogenic tissue and they may be responsible for the one-third of the epileptic patients who were refractory to anti-epileptic drugs (AEDs). Since several AEDs may act as substrates for these drug resistant proteins, the enhanced function of such proteins may increase drug extrusion, resulting in inadequate response to drug therapy in patients with epilepsy. We studied expression of the multidrug resistance protein 1 (MDR1) and multidrug resistance-associated protein 1 (MRP1) in the epileptic tissues resected surgically in 28 patients with focal cortical dysplasia (FCD) by immunohistochemistry. The results were compared with 10 normal necropsy brain tissues. Normal brain showed no MDR1 expression in neurons and astrocytes, while MRP1 expression was very weak, which were encountered in a few samples. MDR1 expression was mainly localized on the vascular endothelial cells. In contrast to normal brain, we found intense MDR1 and MRP1 expression in both neurons and reactive astrocytes in the vast majority of dysplastic tissues. The majority of the dysplastic neurons demonstrated moderate to strong MRP1 immunoreactivity. Endothelial cells showed both MDR1 and MRP1 expression in the majority of the specimens studied. Multidrug transporters are over-expressed in the epileptogenic zone in patients with FCD. These results are concordant with previous studies, in which over-expression of multidrug proteins were shown in epileptogenic brain tissue in patients with FCD, that the over-expression of drug transport proteins in tissue from patients with refractory epilepsy may explain one possible mechanism for drug resistant in these pathologies.

Anaplastic oligoastrocytoma: previous treatment as a possible cause in a child with acute lymphoblastic leukemia

INTRODUCTION

The authors present a 14-year-old patient who developed an anaplastic oligoastrocytoma of the left parietal lobe 9 years after a successful treatment of acute lymphoblastic leukemia (ALL). He had a history of induction chemotherapy, intrathecal methotrexate and prophylactic whole brain irradiation (1,800 cGy in 10 fractions over 2 weeks).

DISCUSSION

Radiation-induced neoplasia is suggested to be the late complication of ALL treatment, and evaluation of large clinical series revealed a relationship between young age at ALL diagnosis (<6 years) and increased high-grade glioma occurrence risk.

CONCLUSION

The authors have reviewed previously reported cases of secondary central nervous system malignancies focusing on age at ALL diagnosis, and they think that synergistic action of therapeutic modalities could have played a role in the oncogenetic process. Detailed systematic radiological follow-up should be done in these patients especially if a personal history of cranial irradiation is present.

A Rhizopus oryzae strain isolated from resected bone and soft tissue specimens from a sinonasal and palatal mucormycosis case. Report of a case and in vitro experiments of yeastlike cell development

We report a histologically and mycologically proven sinonasal mucormycosis case causing palatal necrosis in a nondiabetic patient with renal failure. Mycological examination of Giemsa stained imprinted tissue preparations revealed abundant yeast-like cells besides the typical mucoraceous hyphae. The fungus was isolated from surgical specimens and identified as Rhizopus oryzae by phenotypic and genotypic tests. Laboratory studies were performed to investigate the association of the yeast-like cells observed in tissue specimens and the fungus recovered in culture. In vitro induced yeast-like cell development of the case isolate was found under certain growth conditions and documented by photomicrographs.

Adult intramedullary mature teratoma of the spinal cord: review of the literature illustrated with an unusual example

Intramedullary mature teratomas particularly in adults are rarely encountered. In this manuscript the authors have reviewed the adult intramedullary lesions of the spinal cord published in the literature that are harbouring the characteristics of a mature teratoma and analysed the results with respect to histopathology, epidemiology, diagnostic methods and treatment. An illustrative case of an extremely unusual localization is also presented.

Autocrine motility factor receptor expression implies an unfavourable prognosis in resected stage I pulmonary adenocarcinomas

BACKGROUND

Pulmonary adenocarcinomas constitute a different histological subtype among the histological subtypes of non small cell lung carcinomas by showing comparably unfavourable rates of prognosis and different immunobiological features. Autonomous motility of tumour cells plays an important role in the regulation of local invasion and distant metastasis of tumour lesions which have great impact on overall survival. AMF (Autocrine motility factor) is a tumour secreted cytokine that stimulates motility during invasion and metastasis via its receptor, AMFR. We conducted an immunohistochemical study to investigate AMFR expression in pulmonary adenocarcinomas and its effect on survival.

MATERIAL AND METHODS

We assessed AMFR expression using a monoclonal antibody (3F3A) in a total of 32 surgical specimens with stage I pulmonary adenocarcinomas that underwent curative resection. We analyzed AMFR expression as a possible prognostic factor on survival and its correlations with clinicopathological features.

RESULTS

A total of 19 (59.3%) specimens showed AMFR expression. The 3-year survival rates of AMFR positive and AMFR negative patients were 47.3% and 84.6%, respectively, which was a significant difference (P = 0.0197). The univariate predictors of surgical outcome were AMFR expression (P = 0.032) and perineural invasion (P = 0.038). However, multivariate analysis revealed AMFR expression (P = 0.045) as the only independent prognostic factor.

CONCLUSIONS

AMFR expression predicts an unfavourable surgical outcome in patients with stage I pulmonary adenocarcinomas.

Altered gene profiles in fetal rat testes after in utero exposure to di(n-butyl) phthalate

Di(n-butyl) phthalate (DBP) has antiandrogenic-like effects on the developing reproductive tract in the male rat and produces regions of interstitial cell hyperplasia and gonocyte degeneration in the developing fetal testes at maternal doses of 100-500 mg/kg/day. Neither DBP nor its primary metabolites interact with the androgen receptor in vitro. The present study was performed to examine gene expression in the fetal rat testes following in utero DBP exposure. Pregnant Sprague-Dawley rats received corn oil, DBP (500 mg/kg/day), or flutamide (reference antiandrogen, 50 mg/kg/day) by gavage daily from gestation day (GD) 12 to 21. Dose levels were selected to maximize fetal response with minimal maternal toxicity. Testes were isolated on GD 16, 19, and 21. Global changes in gene expression were determined by microarray analysis. Selected genes were further examined by quantitative RT-PCR. DBP, but not flutamide, reduced expression of the steroidogenic enzymes cytochrome P450 side chain cleavage, cytochrome P450c17, and steroidogenic acute regulatory protein. Testicular testosterone and androstenedione were decreased on GD 19 and 21, while progesterone was increased on GD 19 in DBP-exposed testes. Testosterone-repressed prostate message-2 (TRPM-2) was upregulated, while c-kit (stem cell factor receptor) mRNA was downregulated following DBP exposure. TRPM-2 and bcl-2 protein staining was elevated in GD 21 DBP-exposed Leydig and Sertoli cells. Results of this study have led to the identification of several possible mechanisms by which DBP can induce its antiandrogenic effects on the developing male reproductive tract without direct interaction with the androgen receptor. Our results suggest that the antiandrogenic effects of DBP are due to decreased testosterone synthesis. In addition, enhanced expression of cell survival proteins such as TRPM-2 and bcl-2 may be involved in DBP-induced Leydig cell hyperplasia, whereas, downregulation of c-kit may play a role in gonocyte degeneration. Future studies will explore the link between these identified gene expression alterations and ultimate adverse responses.

Induction of hepatic aromatase by p,p'-DDE in adult male rats

1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE, DDE) is a stable metabolite of the pesticide DDT and a persistent environmental pollutant. Earlier reports have demonstrated that DDE is an endocrine-active compound capable of affecting early-stage sexual differentiation in male rats. Experiments based on receptor binding affinity and receptor-mediated transcriptional activation have identified DDE as an androgen receptor antagonist. Other effects of DDE include modulation of the expression and activity of cytochrome P450 (CYP) enzymes, some of which function as steroid hydroxylases, and elevation of serum estrogen levels in treated male rats. These effects suggest the possibility of DDE-caused induction of aromatase, a member of CYP family that catalyzes the conversion of C19 steroids to estrogens. The present study was conducted to determine whether hepatic aromatase was responsive to DDE treatment. We found that hepatic aromatase protein in adult male rats was greatly increased after seven daily oral treatments of DDE at a dosage of 100 mg/kg wt. per day. This induction was seen in both immunoblot and immunohistochemistry of liver tissue sections. Distribution of the aromatase in the liver corresponded to the distribution of hypertrophic hepatocytes in the tissue. Furthermore, we found a large increase in hepatic microsomal aromatase activity in DDE-treated animals, although the difference in serum 17beta-estradiol concentrations between treated animals and controls was not statistically significant. However, an in vitro experiment using primary culture of rat hepatocytes did not show a change in aromatase level after DDE treatment at four concentrations ranging from 0 to 5x10(-6) M for 24 h. Meanwhile, CYP 2B1 induction, a known DDE effect in primary rat hepatocyte culture, was seen in those cells. This study supports the notion that induction of aromatase by DDE is a contributory factor to its reproductive developmental effects.

Effects of phthalate esters on the developing reproductive tract of male rats

Phthalate esters are a large group of chemical agents used predominantly as plasticizers and solvents. Certain members of this chemical class have been shown to cause reproductive and developmental toxicity. Recent attention has focused on the potential of these agents to interfere with male reproductive development through a postulated antiandrogenic mechanism. Observations have focused on di-n-butyl phthalate (DBP), di-(2-ethylhexyl) phthalate (DEHP) and butyl benzylphthalate, with most information relating to dose-response relationships obtained for DBP. Neither DBP, DEHP nor their major metabolites interacted with human or rodent androgen receptors (AR) in transcriptional activation assays. DBP was administered during the critical window of development of the male reproductive system, after which the resulting offspring were examined until adulthood. DBP elicited marked effects on the developing male reproductive tract, including malformations of the epididymis and vas deferens, and hypospadias. Retention of thoracic nipples/areolae and reductions in anogenital distance were also noted. Surprisingly, Leydig cell adenomas were induced in some male offspring at 100 days of age. All these events occurred in the absence of any toxicity in the pregnant dam. Examination of testes from fetal rats indicated markedly reduced testosterone levels and increased Leydig cell numbers after DBP administration to the dams. Leydig cells were positive for AR and 3-betahydroxysteroid dehydrogenase.

Oestrogen receptor alpha and beta in rat prostate and epididymis

The cellular localization of two oestrogen receptor (ER) subtypes, ER alpha and ER beta, was investigated in neonatal, postnatal, immature and adult male rats to determine whether these receptor subtypes are differentially expressed in prostate and epididymis. A monoclonal antibody against ER alpha and two polyclonal ER beta antibodies were used. Paraffin sections revealed a specific nuclear immunoreaction product in certain cells but not in others. In the epididymis, nuclear ER alpha immunoreactivity (IR) was detected in epithelial cells of efferent ductules and initial segments as well as in connective tissue surrounding the tubules in caput, corpus and cauda. No IR was observed in rete testis. Epithelial cells of the prostate lacked ER alpha IR, but connective tissue cells surrounding prostatic buds in the early neonatal period revealed IR. In prostate, ER beta IR was expressed in epithelial cells of the ventral and dorsolateral lobes, but the IR intensity was higher in the ventral lobe. In neonatal rats, ER beta was expressed in the epididymis but not in the prostate gland. Weak ER beta expression was found in the prostates of 5-day-old rats, and the reaction increased in intensity thereafter. In the epididymis, a similar developmental expression pattern of ER beta was observed. ER beta expression in prostate and epididymis was similar to expression of androgen receptors reported previously for these organs. The results support that both ER alpha and ER beta may be involved in oestrogen modulation of prostate and epididymal functions.

Postnatal sex reversal of the ovaries in mice lacking estrogen receptors alpha and beta

Mice lacking estrogen receptors alpha and beta were generated to clarify the roles of each receptor in the physiology of estrogen target tissues. Both sexes of alphabeta estrogen receptor knockout (alphabetaERKO) mutants exhibit normal reproductive tract development but are infertile. Ovaries of adult alphabetaERKO females exhibit follicle transdifferentiation to structures resembling seminiferous tubules of the testis, including Sertoli-like cells and expression of Müllerian inhibiting substance, sulfated glycoprotein-2, and Sox9. Therefore, loss of both receptors leads to an ovarian phenotype that is distinct from that of the individual ERKO mutants, which indicates that both receptors are required for the maintenance of germ and somatic cells in the postnatal ovary.

Immunocytochemical analysis of the glucocorticoid receptor alpha isoform (GRalpha) using GRalpha-specific antibody

The alpha isoform of the glucocorticoid receptor (GRalpha) binds glucocorticoids and functions as a ligand-dependent transcription factor. Although GRalpha is expressed in almost all tissues and cells, its subcellular distribution is controversial. Many studies have reported that GRalpha translocates from the cytoplasm to the nucleus in a hormone-dependent manner whereas others have concluded that GRalpha is constitutively located in the nucleus. These conflicting data may result from the use of antibodies that do not discriminate GRalpha from a splice variant of the GR gene termed GRbeta. Using a GRbeta-specific antibody, we have recently demonstrated that GRbeta resides in the nucleus of cells independent of glucocorticoid treatment. In the following study we have generated a novel GRalpha-specific antibody (AShGR) in order to assess, unambiguously, the subcellular distribution of GRalpha. AShGR recognizes recombinant GRalpha on Western blots and in immunoprecipitation experiments but does not cross-react with recombinant GRbeta. Endogenous GRalpha is detected by AShGR in a variety of human cell lines including HeLa S3, CEM-C7, HEK-293, MCF-7, Hep G2, and secondary lung epithelial cells. In addition, AShGR detects endogenous rat and mouse GRalpha. Immunocytochemistry was performed with AShGR on COS-I cells transfected with human GRalpha and on HTC rat hepatoma cells expressing endogenous GRalpha. In both systems, GRalpha was found in the cytoplasm of cells in the absence of hormone and in the nucleus after hormone treatment. These studies mark the first time a GRalpha-specific antibody has been employed to examine the expression and subcellular distribution of endogenous GRalpha.

Targeted disruption of the estrogen receptor-alpha gene in female mice: characterization of ovarian responses and phenotype in the adult

Targeted disruption of the mouse estrogen receptor-alpha gene (estrogen receptor-alpha knockout; ERKO) results in a highly novel ovarian phenotype in the adult. The ERKO mouse model was used to characterize ER alpha-dependent processes in the ovary. Visualization of the ovaries of 10-, 20-, and 50-day-old wild-type (WT) and ERKO mice showed that the ERKO phenotype developed between 20 and 50 days of age. Developmental progression through the primordial, primary, and antral follicle stages appeared normal, but functional maturation of preovulatory follicles was arrested resulting in atresia or in anovulatory follicles, which in many cases formed large, hemorrhagic cysts. Corpora lutea were absent, which also indicates that the normal biochemical and mechanical processes that accomplish ovulation were compromised. Northern and ribonuclease protection analyses indicated that ERKO ovary FSH receptor (FSHR) messenger RNA (mRNA) expression was approximately 4-fold greater than in WT controls. Ovarian LH receptor (LHR) mRNA expression was also higher in the ERKO animals. Cellular localization studies by in situ hybridization analysis of ERKO ovaries showed a high level of LHR mRNA expression in the granulosa and thecal layers of virtually all the antral follicles. Ribonuclease protection analyses showed that ovarian progesterone receptor and androgen receptor mRNA expression were similar in the two groups. These results indicated that ER alpha action was not a prerequisite for LHR mRNA expression by thecal or granulosa cells or for ovarian expression of progesterone receptor mRNA. Ovarian estrogen receptor beta (ER beta) was detected immunohistochemically, was sharply compartmentalized to the granulosa cells, and was expressed approximately equally in the ERKO animals and the WT controls. In contrast, ER alpha staining was present in the thecal cells but not the granulosa cells of the WT animals. The summary findings indicate that in the adult the major cause of the ERKO phenotype is high circulating LH interacting with functional LHR of the theca and granulosa cells. These features result in a failure of the normal maturational events leading to successful ovulation and luteinization and presumably involve both hypothalamic-pituitary and intraovarian mechanisms dependent upon ER alpha action. The presence of ER beta in the granulosa cells did not rescue the phenotype of the ovary.

Disruption of androgen-regulated male reproductive development by di(n-butyl) phthalate during late gestation in rats is different from flutamide

Gestational and lactational exposure to di(n-butyl) phthalate (DBP) at >/=250 mg/kg/day disrupts male rat reproductive development and function. Although this indicates an antiandrogenic mechanism, DBP and its biologically active metabolite do not interact with the androgen receptor (AR) in vitro. In the present study, we compared the effects of DBP and the antiandrogen flutamide using a shorter exposure during the prenatal period of male sexual differentiation in rats. Pregnant CD rats received DBP at 0, 100, 250, or 500 mg/kg/day po (n = 10) or flutamide at 100 mg/kg/day po (n = 5) from Gestation Days 12 to 21. In F1 males, DBP (500 mg/kg/day) and flutamide caused hypospadias; cryptorchidism; agenesis of the prostate, epididymis, and vas deferens; degeneration of the seminiferous epithelium; and interstitial cell hyperplasia of the testis. Flutamide and DBP (250 and 500 mg/kg/day) also produced retained thoracic nipples and decreased anogenital distance. Interstitial cell adenoma occurred at 500 mg DBP/kg/day in two males. The only effect seen at 100 mg DBP/kg/day was delayed preputial separation. In contrast to flutamide, DBP caused a low incidence of prostate agenesis and hypospadias with no vaginal pouch. The low incidence of DBP-induced intraabdominal testes contrasted with the high incidence of inguinal testes seen with flutamide. Thus prenatal male sexual differentiation is a sensitive period for the reproductive toxicity of DBP. A no observed adverse effect level was not established and the lowest observed (adverse) effect level was 100 mg/kg/day. Flutamide and DBP disrupted the androgen signaling necessary for male sexual differentiation but with a different pattern of antiandrogenic effects. DBP is an example of an environmental antiandrogen that disrupts androgen-regulated male sexual differentiation without interacting directly with the AR, as does flutamide.

Differential expression of estrogen receptor-beta and estrogen receptor-alpha in the rat ovary

Immunohistochemical localization of two estrogen receptor (ER) subtypes, ER beta and ER alpha, was performed in neonatal, early postnatal, immature, and adult rats to determine whether ER alpha and ER beta are differentially expressed in the ovary. ER beta and ER alpha were visualized using a polyclonal anti-ER beta antibody and a monoclonal ER alpha (ID5) antibody, respectively. Postfixed frozen sections and antigen-retrieved paraffin sections of the ovary revealed nuclear ER beta immunoreactivity (IR) in granulosa cells, which was prevented when peptide-adsorbed antibody was used instead. In immature and adult rat ovaries, ER beta was expressed exclusively in nuclei of granulosa cells of primary, secondary, and mature follicles. Atretic follicle granulosa cells showed only weak or no staining. No specific nuclear ER beta IR was detected in thecal cells, luteal cells, interstitial cells, germinal epithelium, or oocytes. In neonatal rat ovary, no ER beta expression was found. In ovaries of 5- and 10-day-old rats, weak ER beta IR was observed in granulosa cells of primary and secondary follicles, but no staining was detected in the primordial follicles. ER alpha protein exhibited a differential distribution in the ovary with no detectable expression in the granulosa cells but evidence of ER alpha IR in germinal epithelium, interstitial cells, and thecal cells. In the oviduct and uterus, IR for ER alpha, but not ER beta, was found in luminal epithelium, stromal cells, muscle cells, and gland cells. Our present study demonstrates that ER beta and ER alpha proteins are expressed in distinctly different cell types in the ovary. The exclusive presence of ER beta in granulosa cells implies that this specific new subtype of ER beta mediates some effects of estrogen action in the regulation of growth and maturation of ovarian follicles.

Generation and reproductive phenotypes of mice lacking estrogen receptor beta

Estrogens influence the differentiation and maintenance of reproductive tissues and affect lipid metabolism and bone remodeling. Two estrogen receptors (ERs) have been identified to date, ERalpha and ERbeta. We previously generated and studied knockout mice lacking estrogen receptor alpha and reported severe reproductive and behavioral phenotypes including complete infertility of both male and female mice and absence of breast tissue development. Here we describe the generation of mice lacking estrogen receptor beta (ERbeta -/-) by insertion of a neomycin resistance gene into exon 3 of the coding gene by using homologous recombination in embryonic stem cells. Mice lacking this receptor develop normally and are indistinguishable grossly and histologically as young adults from their littermates. RNA analysis and immunocytochemistry show that tissues from ERbeta -/- mice lack normal ERbeta RNA and protein. Breeding experiments with young, sexually mature females show that they are fertile and exhibit normal sexual behavior, but have fewer and smaller litters than wild-type mice. Superovulation experiments indicate that this reduction in fertility is the result of reduced ovarian efficiency. The mutant females have normal breast development and lactate normally. Young, sexually mature male mice show no overt abnormalities and reproduce normally. Older mutant males display signs of prostate and bladder hyperplasia. Our results indicate that ERbeta is essential for normal ovulation efficiency but is not essential for female or male sexual differentiation, fertility, or lactation. Future experiments are required to determine the role of ERbeta in bone and cardiovascular homeostasis.

Androgen receptor expression in the testes and epididymides of prenatal and postnatal Sprague-Dawley rats

The androgen receptor (AR) plays a critical role in sexual differentiation and in the virilization of the male reproductive system. A clear understanding of AR expression at the early stages of sexual development will help elucidate the sensitivity of perinatal animals to endocrine modulation by external agents, such as some environmental chemicals. Immunohistochemistry was used in this study to localize the AR in the differentiating testis and epididymis of Sprague-Dawley rats starting from gestation day 15 until postnatal day 21. Positive AR staining was found on gestation day 15 in the mesenchymal as well as in the epithelial cells in the mesonephros. Weak staining was also observed in a small number of interstitial cells in the primordial testis at this age. The fetal interstitial and peritubular myoid cells showed positive AR immunoreactivity early in development, but the Sertoli cells did not overtly express the receptors until postnatal day 5. The intensity of staining and number of AR-positive cells in the testis and epididymis increased over time. The epithelium in the mesonephros-derived tissues, including rete testis and epididymis, appeared to exhibit a higher capacity to express AR than the rest of the testicular tissue. The results demonstrate that AR expression in the primordial male reproductive system is highly specific to time and cell type and modify previous understanding on the timing of AR expression in the testicular tissue. Since AR-positive cells at various developmental stages may be potential sites of interaction with chemicals that adversely affect sexual differentiation, improved understanding of AR ontogeny will help in investigating the effects of AR-reactive agents, such as environmental antiandrogens, with respect to specific windows of sensitivity.