Anorectal Malignant Melanoma Post- Hemorrhoidectomy

Anorectal malignant melanoma, a rare and aggressive tumor, lacks specific symptoms and frequently presents diagnostic challenges due to its similarity to benign anorectal conditions. This case report describes the diagnostic and treatment process of incidentally discovered anorectal malignant melanoma post-hemorrhoidectomy, guided by the existing literature.

Reliability and validity of the Turkish version of the New Cleveland Clinic Colorectal Cancer Quality of Life Questionnaire

PURPOSE

This study aims to adapt and validate the Cleveland Clinic Colorectal Cancer Quality of Life Questionnaire (CCF-CaQL) in Turkish, addressing the significant need for reliable, language-specific QoL measures for colorectal cancer (CRC) in Turkiye. This effort fills a critical gap in CRC patient care, enhancing both patient-provider communication and disease-specific QoL assessment.

METHODS

The CCF-CaQL was translated into Turkish, verified for accuracy, and reviewed for clarity and relevance. Eligible patients who underwent colorectal surgery for cancer between July 2021 and July 2022 from six hospitals completed the CCF-CaQL and SF-36 questionnaires. For analysis, confirmatory factor analysis using Smart PLS 4 and descriptive statistics were employed. The questionnaire's reliability and validity were assessed using Cronbach alpha, composite reliability, and the heterotrait-monotrait (HTMT) ratio, along with multicollinearity checks and factor loadings. Nonparametric resampling was used for precise error and confidence interval calculations, and the Spearman coefficient and split-half method were applied for reliability testing.

RESULTS

In the study involving 244 colorectal cancer patients, confirmatory factor analysis of the CCF-CaQL indicated effective item performance, with one item removed due to lower factor loading. The questionnaire exhibited high internal consistency, evidenced by a Cronbach alpha value of 0.909. Convergent validity was strong, with all average variance extracted (AVE) values exceeding 0.4. Discriminant validity was confirmed with HTMT coefficients below 0.9, and no significant multicollinearity issues were observed (VIF values < 10). Parallel testing with the SF-36 scale demonstrated moderate to very strong correlations, affirming the CCF-CaQL's comparability in measuring quality of life.

CONCLUSION

The Turkish version of the CCF-CaQL was validated for assessing quality of life in colorectal cancer patients. This validation confirms its reliability and cultural appropriateness for use in Turkiye. The disease-specific nature of the CCF-CaQL makes it a useful tool in clinical and research settings, enhancing patient care by accurately monitoring treatment effects and interventions in the Turkish colorectal cancer patient population.

Benign Multicystic Peritoneal Mesothelioma: Two Rare Cases and Review of the Literature

BACKGROUND

Benign multicystic peritoneal mesothelioma is a multiloculated cystic mass which originates from the peritoneum. This rare tumor is usually seen in women of childbearing age and has a high recurrence rate after surgery.

CASE PRESENTATION

We present two benign multicystic peritoneal mesothelioma cases with different imaging modalities, which were also pathologically proven.

CONCLUSION

The imaging features which may be diagnostic should be well known as there are very few reports regarding this entity.

Gardner's syndrome: Simultaneous diagnosis and treatment in monozygotic twins

Gardner's syndrome (GS) is a very rare autosomal dominant multisystem disease. Osteomas, skin and soft tissue tumors are present with gastrointestinal polyposis. The polyps have very high malignancy potentials. If prophylactic resection is not performed, colorectal cancer development is inevitable in all patients with GS. Polyposis is usually asymptomatic. Therefore, careful evaluation of extraintestinal findings of the disease is very important for early diagnosis. In this article, diagnosis and treatment of GS are presented in monozygotic twins, which have not been previously described in the literature. The diagnostic process, which started with dental complaints of one case, was carried out in an effective manner and then, prophylactic surgery was performed in twins. This article aimed to make clinicians and dentists attentive for early diagnosis of disease and to review treatment options.

Effects of Patient and Tumor Characteristics on Central Lymph Node Metastasis in Papillary Thyroid Cancer: A Guide for Selective Node Dissection

BACKGROUND

Prophylactic central lymph node dissection (CLND) in papillary thyroid carcinoma (PTC) is still controversial. This study aimed to analyze the factors related to the patient and tumor characteristics affecting central lymph node metastasis (CLNM) in PTC patients and to evaluate the contribution of the results to shaping the surgical treatment algorithm.

METHODS

Two hundred and fifty-five PTC patients who underwent total thyroidectomy and CLND were evaluated retrospectively. Histopathology reports were examined to reveal tumor characteristics. The CLNM ratio and the relationship between CLNM with clinicopathological and demographic characteristics were analyzed.

RESULTS

The incidence of CLNM was 54.9% (95 CI%: 49-60.8). Male gender (P=0.027), age<45 years (P=0.016), tumor size≥9.5 mm (P<0.001), lymphovascular invasion (P<0001) and extracapsular invasion (P=0.007) were factors that increased the risk of metastasis. The follicular variant decreased the risk (P=0.010). There was no relationship between CLNM and focality (P=0.054). A low-to-moderate correlation was found between tumor diameter and the metastatic lymph node (MLN) number/total lymph node number ratio (r=0.396, P<0.001).

CONCLUSION

A selective prophylactic CLND strategy can be applied in cN0 patients. As the tumor diameter increases in PTC, both the risk of CLNM and the number of MLN increase. Lymphovascular and extracapsular invasion are other factors that increase the risk. The follicular variant is associated with a lower risk of CLNM. Male patients who are under the age of 45 and have a tumor diameter of 9.5 mm or more are definite candidates for prophylactic CLND.

Comparison of the results of using a self-adhesive mesh and a polypropylene mesh in open inguinal hernia repair: a prospective randomized controlled study

Background: Inguinal hernia repair is the most common operation worldwide. The essential factors in hernia repair have been the postoperative quality of life, early return to work, low recurrence rate, and chronic pain prevention. The objective of this study was to compare the short- and long-term results of the self-adhesive mesh and the conventional polypropylene mesh in Lichtenstein repair. Methods: A total of 100 male patients were randomized and operated on, 50 with the self-adhesive mesh (S group), 50 with conventional polypropylene mesh (P group). Prospectively, the patients were followed for an average of 36 months. The two groups were compared for the duration of surgery, duration of hospital stay, duration of daily activity/resumption of work, postoperative pain, chronic pain, recurrence, wound infection, hematoma/seroma formation, and postoperative analgesic consumption. Results: The study involved 39 patients in the P group and 37 patients in the S group who underwent inguinal hernia surgery. The P group had a longer mean operation time than the S group, and the difference between the two groups was statistically significant (45.1 ± 6.6 min vs. 28.8 ± 3.0 min, p= 0.0001). In recurrence, postoperative discomfort, chronic pain, length of hospital stay, daily activity/return to work, wound infection, hematoma/seroma, and postoperative analgesic use, there was no statistically significant difference between the two groups. Conclusion: It was found that the self-adhesive mesh did not produce statistically significant advantages over the conventional polypropylene mesh, except for operative time, in the Lichtenstein repair.

A new criterion to predict recurrence after laparoscopic ventral hernia repair: mesh/defect area ratio

<b>Introduction:</b>Minimizing recurrence in hernia surgery is one of the major aims. Defining surgeon-dependent risk factors for recurrence is therefore of great importance in laparoscopic ventral hernia repair (LVHR). This study aims to analyze the predictive value of the mesh area/defect area ratio (M/D ratio) in terms of recurrence as a new criterion in LVHR.</br> </br> <b>Methods:</b> A total of 124 patients were enrolled in the study. Age, gender, hernia type, body mass index, defect size, size of the mesh, mesh overlapping, area of the defect, area of the mesh, M/D ratio, postoperative complications, follow-up time, recurrences and timing of recurrence were also recorded. The potential variables that may affect recurrence were examined by univariate and multivariate analysis.</br> </br> <b>Results:</b> There were 12 (9.7%) recurrences in our series. A statistically significant difference was found if either the mesh/defect ratio was ≤6 or >6 (p = 0.012). Multivariate analysis confirmed that M/D ratio was the only independent parameter for recurrence. </br></br><b>Conclusion:</b> Understanding M/D ratio concept and using it in surgical clinical practice may help reduce recurrence rates after LVHR.</br>

Surgical Complications After Deceased Donor Renal Transplant

OBJECTIVES

Deceased donor renal transplant is an accepted treatment for patients with end-stage renal disease. We retrospectively analyzed urological and surgical complications and outcomes in our series.

MATERIAL AND METHODS

Since 2016, we have performed 263 renal transplants at the Gazi University Transplantation Center, Ankara, and 92 of these were from deceased donors. We retrospectively analyzed outcomes of these 92 deceased donor transplants from our database records. There were 45 female and 47 male recipients, and 20 were pediatric recipients. Mean recipient and donor ages were 36 ± 14 and 38 ± 18 years old, respectively. Immunosuppression therapy consisted of steroids, mycophenolate, and calcineurin inhibitors. Induction therapy was 20 mg basiliximab (Simulect) on day 0 and day 4. Antithymocyte globulin (2 mg∕kg) was used in steroid-resistant acute rejection cases.

RESULTS

There were 13 surgical complications (14.1%) after 92 consecutive deceased donor renal transplants, and 4 of these were classified as miscellaneous surgical complications. Four of 9 cases were early, and the rest were classified as late complications. Postoperative early complications were bleeding (n = 2), urine leak (n = 1), and renal artery thrombosis (n = 1). Lymphoceles (n = 4) and urine leak (n = 1) occurred as late complications. Postoperative median follow-up was 78 months, during which 11 grafts (12%) were lost and 7 patients (7.6%) died from sepsis (n = 4), myocardial infarction, aortic dissection, and fungal pneumonia. No patients died from any surgical complications. The 1-year, 5-year, and 10-year survival rates of patients were 98%, 94%, and 94% and for grafts were 97%, 94%, and 88%, respectively.

CONCLUSION

Despite the limited number of deceased donor organs, improvements of surgical techniques at our center have facilitated success with deceased donor renal transplant at rates similar to other successful centers in the world.

Routine Histopathological Examination of the Specimen After Laparoscopic Cholecystectomy: Can We Be Brave Enough to Give Up?

BACKGROUND

Selective versus routine histopathological examination after cholecystectomy is still in debate. This study aims to investigate the effect of histopathology results on treatment modality and surgery strategy. The validity of the selective histopathology approach was questioned.

METHODS

The data of patients undergoing laparoscopic cholecystectomy between January 2009 and December 2019 were retrospectively analyzed. The demographics and histopathology results, whether the operation was emergent or elective, and the reasons for conversion to open surgery were recorded. Malignant and precursor histopathology diagnoses were examined, and their relationship with the surgical strategy was questioned.

RESULTS

A total of 2723 patients were included in the study. Of these patients, 2600 (95.5%) were operated under elective, while 123 (4.5%) were operated under emergency conditions. While the surgery was completed laparoscopically in 2685 (98.6%) patients, it was converted to open surgery in 38 (1.4%) patients. Age, gender, the presence of primary gallbladder cancer, acute cholecystitis, and xanthogranulomatous cholecystitis in histopathological examination were found to be independent predictive factors for conversion to open surgery (P < .05). The rate of primary invasive carcinoma in the series was 0.1%.

CONCLUSION

Routine histopathological examination of the gallbladder is important for demonstrating a wide spectrum of pathological changes in this organ. Invasive cancer or precursor lesions can be detected even in patients without any macroscopic abnormality. Histopathological examination also plays a role in determining follow-up, further examination, and treatment modality in addition to the diagnosis in these patients.

Succinivibrionaceae is dominant family in fecal microbiota of Behçet's Syndrome patients with uveitis

Behçet’s Syndrome (BS) is a multisystem vasculitis with various clinical manifestations. Pathogenesis is unclear, but studies have shown genetic factors, innate immunity and autoinflammation to have an important role in the disease course. Diversity in the microbial community of gut microbiota may significantly contribute to the activation of the innate immune system. The clinical features of BS present themselves in clusters and each cluster may be a consequence of different disease mechanisms. For this reason we aimed to investigate the gut microbiota of BS patients with uveitis. In addition to healthy controls, we have aimed to compare the gut microbiota of BS with that of Familial Mediterranean Fever (FMF) and Crohn’s Disease (CD) as both diseases have innate and autoinflammatory features in their pathogenesis. Seven patients with BS, 12 patients with FMF, 9 patients with CD and 16 healthy controls (HC) were included in the study. Total genomic DNAs were isolated from fecal samples of the patients. Partial 16S rRNA gene was sequenced using the PGM Ion Torrent (Thermo Fisher Scientific, Waltham, MA, USA) for microbiota analysis. Statistical analysis showed that significant differences were detected on the microbial community of four groups. Succinivibrionaceae is dominant and the signature family, whereas Bacteroides was absent in BS patients.

Granulomatous mastitis, watch and wait is a good option

BACKGROUND

Idiopathic granulomatous mastitis (IGM) is a benign and rare chronic inflammatory disease of the breast with unknown etiology. While there is no consensus regarding its post-diagnosis management, there are different treatment alternatives.

AIMS

In this study, it was aimed to question the effectiveness of follow-up strategy without administering any treatment.

METHODS

One hundred eighteen female patients diagnosed with IGM were retrospectively evaluated. Patients with histopathologically confirmed IGM were included in the study. Medical treatment was given only to patients who did not accept the follow-up option without treatment. The protocol used in steroid therapy was 16 mg prednisolone twice daily for 2 weeks, and then the dose was gradually reduced, and the treatment was stopped after 2 months. Patients were followed up with a physical examination every 3 months. The effectiveness of the systemic corticosteroid treatment and the follow-up approach without any treatment was compared. The recurrence rates and pre-treatment and post-treatment methods of the patients were examined.

RESULTS

While 30.5% of the patients recovered with corticosteroid treatment, 42.4% recovered under observation without any treatment. The mean recovery period of the patients in these two groups was calculated as 3.9 months and 5.6 months, respectively. However, no statistically significant difference was found in terms of recovery period (p = 0.064). The recurrence rate was 11.9%.

CONCLUSION

For IGM, the "watch and wait" approach is an effective option. A chance should be given to the self-limiting nature of the disease with the addition of drainage when necessary.

Effectiveness of new parameters in the evaluation of pneumoperitoneum-related acute kidney injury in rats

Background/aim

Pneumoperitoneum with high pressure results in decreased glomerular filtration rates (GFRs). Cystatin-C (Cys-C), neutrophil gelatinase-associated lipocalin (NGAL), and interleukin 18 (IL-18) are new parameters in the evaluation of GFR instead of creatinine. The aim of this study is to show the effects of pneumoperitoneum on renal function with the help of these new acute kidney injury markers.

Materials and methods

Sixty rats were divided into 10 groups according to the length of time and degree of pneumoperitoneum pressure achieved during CO2 insufflation: 0 mmHg (control) for 1 h; 4 mmHg for 1, 2, and 4 h; 8 mmHg for 1, 2, and 4 h; and 12 mmHg for 1, 2, and 4 h. Serum samples were obtained to measure the serum creatinine, blood urea nitrogen (BUN), Cys-C, NGAL, and IL-18.

Results

There were no differences between the serum creatinine levels of the groups. Serum levels of BUN, Cys-C, NGAL, and IL-18 were significantly increased in the 2nd hour of the experiment. This increase was more prominent at high pressures.

Conclusion

Although serum creatinine is a practical way of estimating GFR, it has been shown that Cys-C, NGAL, and IL-18 are superior in the estimation of decreased GFR in pneumoperitoneum.

Factors affecting successful colonoscopy procedures: Single-center experience

Objective

Colonoscopy is a gold standard procedure for several colon pathologies. Successful colonoscopy means demonstration of the ileocecal valve and determination of colon polyps. Here we aimed to evaluate our colonoscopy success and results.

Material and Methods

This retrospective descriptive study was performed in İstanbul Eren hospital endoscopy unit between 2012 and 2015. Colonoscopy results and patient demographics were obtained from the hospital database. All colonoscopy procedures were performed under general anesthesia and after full bowel preparation.

Results

In all, 870 patients were included to the study. We reached to the cecum in 850 (97.8%) patients. We were unable to reach the cecum in patients who were old and obese and those with previous lower abdominal operations. Angulation, inability to move forward, and tortuous colon were the reasons for inability to reach the cecum. Total 203 polyp samplings were performed in 139 patients. We performed 1, 2, and 3 polypectomies in 97, 28, and 10 patients, respectively. There were 29 (3.3%) colorectal cancers in our series. There was no mortality or morbidity in our study.

Conclusion

General anesthesia and full bowel preparation may be the reason for increased success of colonoscopy. Increased experience and patient-endoscopist cooperation increased the rate of cecum access and polyp resection and decreased the complication rate.

An unusual localization; esophageal melanocytosis

Esophageal melanocytosis is a rare clinical and pathological condition characterized by non-atypical melanocytic proliferation and increased melanin in the esophageal mucosa, which is normally histologically non-melanocytic. Intensive melanin accumulation and hyperpigmentation are necessary for endoscopic recognition. Due to the fact that it is a rare gastrointestinal system pathology, experience and knowledge about its diagnosis, treatment and course are also limited. Although it is argued that chronic stimulating factors have an influence, there is no clear information about its etiology and pathogenesis. Malignant melanomas and melanocytic nevus in particular come to the fore in the differential diagnosis. Opinions and findings indicating that melanocytosis may be a precursor for malignant melanoma make the recognition and follow-up of this clinical and pathological entity more important. In this article, a patient with esophageal melanocytosis diagnosed by endoscopic evaluation is presented, with the aim of increasing the awareness of clinicians, especially endoscopists and pathologists, on this subject.

Duodenal and jejunal Dieulafoy's lesions: optimal management

Dieulafoy's lesions (DLs) are rare and cause gastrointestinal bleeding resulting from erosion of dilated submucosal vessels. The most common location for DL is the stomach, followed by duodenum. There is little information about duodenal and jejunal DLs. Challenges for diagnosis and treatment of Dieulafoy's lesions include the rare nature of the disease, asymptomatic patients, bleeding symptoms often requiring rapid diagnosis and treatment in symptomatic patients, variability in the diagnosis and treatment methods resulting from different lesion locations, and the risk of re-bleeding. For these reasons, there is no universal consensus about the diagnosis and treatment approach. There are few published case reports and case series recently published. Most duodenal DLs are not evaluated seperately in the studies, which makes it difficult to determine the optimal model. In this study, we summarize the general aspects and recent approaches used to treat duodenal DL.

Interaction between carbenoxolone and valproic acid on pentylenetetrazole kindling model of epilepsy

Gap junctions play an important role in the synchronized neuronal discharges. The main reason of the epileptic seizures is disruption of this synchronization. Therefore, the aim of the present study is to explore the combination valproic acid with carbenoxolone in pentylenetetrazole-kindled rats. In the first set of experiments, pentylenetetrazole (35 mg/kg intraperitoneally was administered to the rats to produce the kindling and then permanent screw electrodes to record electroencephalographic signals. The kindled rats were divided into six groups. While electroencephalographic recordings received from animals, behavioral evaluation was done by an observer. The data analysis was performed using T test and Mann-Whitney U tests. The dose of 40 mg/kg carbenoxolone was the most effective in carbenoxolone treatment groups. It prevented generalized seizures by 50%, reduced seizure stage, seizure duration and spike frequency. There was no significant difference between carbenoxolone-valproic acid combination and valproic acid on any seizure parameters. The current study is the first study which shows the interaction of carbenoxolone with valproic acid in pentylenetetrazole kindling model. As a result, carbenoxolone-valproic acid combination was not more effective than the standalone use of these drugs.

Massive lower gastrointestinal bleeding from a jejunal Dieulafoy lesion

Dieulafoy lesion should be considered in massive gastrointestinal bleeding that may be difficult to localize. If the endoscopic and angiographic approaches fail, surgery must be considered according to the patient's clinical condition within an appropriate time. Although mostly seen in the stomach of old male patients with co-morbidities, here we presented a Dieulafoy lesion in the jejunum of a 21-year-old female patient without any significant comorbidity. After endoscopic and angiographic attempts, surgical resection with the help of intraoperative endoscopy was performed. It was shown that perioperative endoscopy may reveal the localization of jejunal bleedings and may guide the definitive treatment.

The effect of alpha-tocopherol in the acute ethanol intake and its withdrawal on penicillin-induced epilepsy

The present study was designed to investigate the influence of acute ethanol intake and its withdrawal on the anticonvulsant effect of alpha-tocopherol in penicillin-induced epileptiform activity. Ethanol-treated rats received a daily dose of 3 g/kg or 9.0 g/kg of 30% ethanol solution for 3 days. Thirty minutes after penicillin injection (500 units, i.c.) the most effective dose of alpha-tocopherol (500 mg/kg) was administered intramuscularly (i.m.). Acute administration of ethanol, in a dose of 3 g/kg, did not change either frequency or amplitude of penicillin-induced epileptiform activity, while dose of 9 g/kg ethanol significantly decreased the mean frequency of penicillin-induced epileptiform ECoG activity in the ethanol-treated group. Ethanol (9 g/kg) withdrawal also caused an increase in the amplitude of epileptiform ECoG activity in the withdrawal group. The results suggest that acute administration of high dose ethanol (9 g/kg) and alpha-tocopherol have some limited anticonvulsive effects in penicillin-induced epileptiform activity in rats.

Anticonvulsant effect of carnosine on penicillin-induced epileptiform activity in rats

Carnosine is a compound of naturally-occurring dipeptide that synthesized by the carnosine synthetase from beta-alanine and l-histidine. Recent reports claim that carnosine plays an important role in the control of epilepsy but its involvement in anticonvulsant functions remains unknown. In this study, we investigated the effects of carnosine in a rat model of epilepsy using the intracortical penicillin injection method. Thirty minutes after penicillin injection, the doses of 125, 250, 500, 1000 mg/kg carnosine and 90 min before penicillin injection the dose of 500 mg/kg carnosine were administered intraperitoneally. The epileptiform activity was verified by electrocorticographic (ECoG) recordings. The mean spike frequency of penicillin-induced epileptiform activity was significantly decreased in all carnosine-treated rats when compared with those of penicillin-injected. The dose of 500 mg/kg for carnosine treated and pretreated rats was found to be the most effective dose in reducing the frequency of penicillin-induced epileptiform activity. There was no significant difference in the mean onset of epileptiform activity between penicillin and 500 mg/kg carnosine pretreated groups. These findings indicate that carnosine has an anticonvulsant effect on penicillin-induced epilepsy in rats. Thus, our data support the hypothesis that carnosine may be a potential anticonvulsant drug for clinical therapy of epilepsy in the future.

Inhibition of neuronal nitric oxide synthase prevents iron-induced cerebellar Purkinje cell loss in the rat

Iron plays an important role in maintaining normal brain function. However, in many neurodegenerative diseases abnormal iron accumulation in specific brain regions has been consistently reported. In this study, we investigated the neurotoxic effect of the intracerebroventricularly injected iron on the cerebellar Purkinje cells in the rat and the role of nitric oxide (NO) in this process. The role of NO in rats administered iron (FeCl36H2O) was examined with the use of a donor of NO, L-arginine (L-Arg) and a central selective inhibitor of NO synthase, 7-nitroindazole (7-NI). For this reason, rats were divided into 5 groups: control, iron-injected, iron plus L-Arg, iron plus 7-NI, and iron plus L-Arg plus 7-NI. Means (value +/- standard deviation) of the total numbers of Purkinje cells in the cerebellum were estimated as 337 +/- 23, 209 +/- 16, 167 +/- 19, 305 +/- 26, and 265 +/- 14 thousands in the control, iron, iron plus L-Arg, iron plus 7-NI, and iron plus L-Arg plus 7-NI groups, respectively. Iron treatment alone and the combination of iron and L-Arg caused a significant reduction in the total number of cerebellar Purkinje cells. Therefore, L-Arg increased the Purkinje cell loss induced by treatment with iron. These data show that inhibition of the neuronal NOS by 7-NI can prevent some of the deleterious effects of iron on cerebellar Purkinje cells. Presence of L-arginine decreased the neuroprotective effect of 7-NI.

High frequency stimulation of the subthalamic nucleus improves speed of locomotion but impairs forelimb movement in Parkinsonian rats

The subthalamic nucleus (STN) plays an important role in motor and non-motor behavior in Parkinson's disease, but its involvement in gait functions is largely unknown. In this study, we investigated the role of the STN on gait in a rat model of PD using the CatWalk method. Parkinsonian rats received bilateral high frequency stimulation (HFS) with different stimulation amplitudes of the STN. Rats were rendered parkinsonian by bilateral injections of 6-hydroxydopamine (6-OHDA) into the striatum. One group of 6-OHDA animals was implanted bilaterally with stimulation electrodes at the level of the STN. Stimulations were performed at 130 Hz (frequency), 60 micros (pulse width) and varying amplitudes of 0, 3, 30 and 150 microA. Rats were evaluated in an automated quantitative gait analysis method (CatWalk method). After behavioral evaluations, rats were killed and the brains processed for histological stainings to determine the impact of the dopaminergic lesion (tyrosine hydroxylase immunohistochemistry) and the localization of the electrode tip (hematoxylin-eosin histochemistry). Results show that bilateral 6-OHDA infusion significantly decreased (70%) the number of dopaminergic cells in the substantia nigra pars compacta (SNc). Due to 6-OHDA treatment, the gait parameters changed considerably. There was a general slowness. The most pronounced effects were seen at the level of the hind paws. Due to implantation of STN electrodes the step pattern changed. STN electrical stimulation improved the general slowness but induced slowing of the forelimb movement. Furthermore, we found that HFS with a medium amplitude significantly changed speed, the so-called dynamic aspect of gait. The static features of gait were only significantly influenced with low amplitude. Remarkably, STN stimulation affected predominantly the forepaws/limbs.

Short-term ethanol administration does not change the total pyramidal neuron number of the rat hippocampus: a stereologic study

In the hippocampus, short-term exposure to ethanol (EtOH) has been shown to inhibit some functions, and nitric oxide (NO) is an important modulator of physiologic processes. In this study, investigators explored the effects of EtOH on the total number of neurons in rat CA regions and the possible neuroprotective role of NO. The role of NO in rats given EtOH was examined with the use of a nonselective inhibitor of NOS (N[G]-nitro-L-arginine methyl ester [L-NAME], D[G]-nitro-Larginine methyl ester [D-NAME]), a central selective inhibitor of NOS (7-NI), and a donor of NO (L-arginine). Toward this end, rats were randomly divided into 6 groups: control (saline 3 g/kg intraperitoneal [ip]), ethanol (ethanol 3 g/kg ip), L-NAME (ethanol 3 g/kg ip + L- NAME 60 mg/kg ip), L-arginine (ethanol 3 g/kg ip + L-arginine 1 g/kg ip), D-NAME (ethanol 3 g/kg ip + D-NAME 60 mg/kg ip), and 7-NI (ethanol 3 g/kg ip + 7-NI 40 mg/kg ip). Blood ethanol concentrations were measured 90 min after EtOH administration. Means (value+/-standard deviation) of total pyramidal neuronal numbers in the right hippocampus were estimated using the optical fractionator counting method. Values were as follows: 446,558+/-6207, 483,517+/-20,311, 464,588+/-30,637, 479,688+/-10,780, 458,294+/-17,770, and 477,281+/-7641 in the control, ethanol, L-arginine, 7-NI, L-NAME, and D-NAME groups, respectively. No significant differences were observed between groups (P>.05). The results of the present study imply that short-term administration of EtOH does not affect total pyramidal neuronal number in the right hippocampus of the rat. Furthermore, NO does not change the effects of short-term EtOH on total pyramidal neuronal number in the right hippocampal CA regions of the rat. Additional studies are needed to clarify the role of NO and NOS inhibition in the effects associated with EtOH given on a short-term basis.

The effects of ethanol intake and withdrawal on penicillin-induced epileptiform activity in rats

Previous experiments have shown that ethanol may have either pro-convulsive or anti-convulsive effects on epileptic activity in different experimental epilepsy models. In this study, the effect of low dose ethanol and its withdrawal on penicillin-induced epileptiform activity in rat was investigated. Eight groups of adult, male Wistar rats were studied: (1) control, (2) penicillin pretreated (500 units), (3) alpha-tocopherol (500 mg/kg, i.m.), (4) penicillin pretreated+alpha-tocopherol, (5) ethanol-treated (3g/kg, per day, for 15 days, intragastrically)+penicillin, (6) ethanol-treated+penicillin+alpha-tocopherol, (7) ethanol withdrawal+penicillin, (8) ethanol withdrawal+penicillin+alpha-tocopherol. Each animal group was composed of seven rats. The epileptiform activity was verified by electrocorticographic (ECoG) recordings. The epileptiform activity was induced by microinjection of penicillin into the left sensorimotor cortex. Administration of ethanol (3g/kg, per day, for 15 days, intragastrically) did not change either frequency or amplitude of penicillin-induced epileptiform activity. The frequency and amplitude of epileptiform activity were evaluated 40 h after the last ethanol administration in withdrawal groups. There was no significant change in the mean frequency and amplitude of epileptiform activity compared with penicillin pretreated and ethanol-treated groups. The effective dose of alpha-tocopherol (500 mg/kg, i.m.) significantly decreased the mean frequency of epileptiform activity in the 60, 70, and 120 min after alpha-tocopherol injection in penicillin pretreated, ethanol-treated, ethanol withdrawal groups, respectively. However, alpha-tocopherol did not affect the amplitude of epileptiform activity in all groups. In conclusion, the present results indicate that low dose of ethanol does not have either anticonvulsive or proconvulsive effect on penicillin-induced epileptiform activity. alpha-Tocopherol has anti-convulsive effect on penicillin-induced epileptiform activity in effective dose.

The influence of ethanol intake and its withdrawal on the anticonvulsant effect of alpha-tocopherol in the penicillin-induced epileptiform activity in rats

Previous studies proposed the existence of a relationship between epilepsy and ethanol. Ethanol may have either proconvulsive or anticonvulsive effects on epileptic activity in different experimental epilepsy models. The influence of high dose ethanol intake and its withdrawal on the anticonvulsant effect of alpha-tocopherol was examined after intracortical injection of penicillin (500 units) to induce epileptiform activity. Thirty minutes after penicillin injection, the most effective dose of alpha-tocopherol (500 mg/kg) was administrated intramuscularly (i.m.). Ethanol-treated rats received a daily dose of 9.0 g/kg of 30% ethanol solution via an oesophageal probe for 15 days. All rats in the withdrawal group were anesthetized for induction of penicillin-induced epileptiform activity 28 h after the last ethanol administration. The epileptiform activity was verified by electrocorticographic (ECoG) recordings. Ethanol, in a dose of 9 g/kg, significantly decreased the mean frequency of penicillin-induced epileptiform ECoG activity without changing the amplitude. The mean frequency of ECoG activity was decreased in the 60 and 70 min period from penicillin injection in the ethanol-treated+alpha-tocopherol and ethanol withdrawal+alpha-tocopherol groups compared with the penicillin-injected (500 units, i.c.) group, respectively. alpha-Tocopherol was more effective in decreasing the mean frequency of epileptiform activity in the ethanol+alpha-tocopherol group than in other alpha-tocopherol administrated groups. Ethanol withdrawal caused an increase in frequency of epileptiform activity in the withdrawal+alpha-tocopherol group compared with other alpha-tocopherol administrated groups. alpha-Tocopherol did not affect the amplitude of epileptiform activity in any group. Possible mechanisms of ethanol influence on the neuroprotective actions of alpha-tocopherol are still a crucial issue associated with epilepsy.

Protection of nigral cell death by bilateral subthalamic nucleus stimulation

In Parkinson disease (PD), the subthalamic nucleus (STN) becomes hyperactive (disinhibited), which is reported to cause excitotoxic damage to midbrain dopaminergic neurons. Here, we examined whether silencing of the hyperactive STN by chronic bilateral deep brain stimulation (DBS) increased the survival of midbrain dopaminergic neurons in a rat model of PD. High-precision design-based stereologic examination of the total number of neurons and tyrosine tydroxylase (TH) immunoreactive neurons in the substantia nigra pars compacta revealed that STN DBS resulted in a significant survival of these neurons. These data provide the first evidence in vivo that bilateral STN DBS is useful for protecting midbrain dopaminergic neurons from cell death in PD.