The effect of acute and chronic formaldehyde exposure on learning and memory in male and female rats.

AIM: Formaldehyde is a chemical that lies behind the various systemical failures in organism. Many products that people use contain formaldehyde. Owing to its tissue fixative properties, scientists who work in life sciences are exposed to this substance more than others. Several studies have shown that formaldehyde affects the CA1 and CA3 regions of the hippocampus, which play crucial roles in memory consolidation. In this study, we aimed to investigate anxiety levels and indicate the short and long term effects of formaldehyde and sex-related differences by exposing formaldehyde to male and female rats. MATERIALS AND METHODS: Formaldehyde (10 mg/kg) was administered intraperitoneally for 7 days for acute exposure and 30 days for chronic exposure. Cognitive assessment was performed using fear conditioning, elevated plus maze, and Morris water maze tests. TUNEL staining was used to identify apoptosis in the brains obtained after decapitation. RESULTS: Exposure to intraperitoneal formaldehyde does not impair learning and memory in acute and chronic periods and has no effect on depression or anxiety. After acute exposure, apoptosis was observed in the hippocampal CA1 and CA3 regions in males. When the cognitive test results were examined, no differences were found between the experimental and control groups. There was also no significant difference between males and females.

Using temporomandibular joint mobility to predict difficult tracheal intubation.

The aim of this prospective study was to determine the reliability of temporomandibular joint (TMJ) mobility measurements for predicting difficult intubation. To evaluate the accuracy in predicting difficult intubation by TMJ mobility measurement, 762 patients requiring general anesthesia with tracheal intubation for elective surgery were enrolled in this prospective, observational, single-blind study. Maximum mouth opening, right-left jaw excursion, and degrees of protraction were determined with a digital inclinometer. Incisor gap was measured using a vernier caliper during full mouth opening. After induction of anesthesia using a standard protocol, the patient's grade of laryngeal view by Cormack-Lehane classification was documented by an anesthesiologist. We found that the degrees of protraction and incisor gap in the easy intubation group were significantly higher than those in the difficult intubation group. The incisor gap was found to be more sensitive (88.37%) and more specific (95.71%) than protraction degrees (58.14% and 59.76%, respectively). The results revealed that measurements of the incisor gap and degrees of protraction may be useful routine screening tests for preoperative prediction of difficult intubation.

Electron microscopic evaluation of the secretory mechanisms of renin from juxtaglomerular cells / Evaluación con microscopía electrónica de los mecanismos secretorios de renina desde las células juxtaglomerulares

Although the structure and the functions of juxtaglomerular cells (JG) have been well defined, there is still a controversy about the secretory mechanisms of renin from these cells. It has been assumed that exocytosis is the main secretory mechanism in these cells in many studies, while others suggest that secretion occurs in a quite different way in these cells. There are several studies suggesting that diacrine secretion, which is very difficult to visualize, might be the other mechanism for secretion of renin. This study is an attempt to find the answers of these questions by identifying the fine structural features of the secretory granules in juxtaglomerular cells. Cyclosporin A (CyA) has been used in the current experimental study since it has already been reported that this drug increases the number of JG cells and stimulates secretion of Renin. Twelve female Sprague-Dawley rats had daily intraperitoneal injections of CyA for ten weeks. Tissue specimens from the kidneys of these animals were examined by electron microscopy. Fine structural characteristics of the secretory granules of juxtaglomerular cells have been examined. Considerable amount of granules, which goes to the exocytotic process, have been observed. Additionally, several cells, which their granules had been secreting their contents in a different way, were found. This was interpreted as the secretion type of diacrine secretion. In conclusion, this in vivo study presents morphologic evidences demonstrating that both exocytosis and diacrine secretion might occur in JG cells. We also had a chance to observe secretory granule probably exhibiting "diacrine secretion", which is very difficult to visualize, at electron microscope level for the first time. This report also provides morphologic proof which shows that these two distinct secretory mechanisms might occur simultaneously in the same juxtaglomerular cell.

Aunque la estructura y las funciones de las células yuxtaglomerulares (JG) han sido bien definidas, todavía existe controversia acerca de los mecanismos de secreción de renina en estas células. Se ha supuesto, en muchos estudios, que la exocitosis es el principal mecanismo de secreción de estas células, mientras que otros autores sugieren que la secreción se produce de una manera muy diferente en estas células. Hay varios estudios que plantean que la secreción diacrina, que es muy difícil de visualizar, podría ser otro mecanismo para la secreción de renina. Este estudio tiene como objetivo encontrar las respuestas a estas interrogantes mediante la identificación de las características estructurales de la secreción de gránulos en las células yuxtaglomerulares. Ciclosporina A (CyA) se ha utilizado en el estudio experimental actual, debido a que se ha informado que este medicamento aumenta el número de células JG y estimula la secreción de renina. Doce ratas hembras Sprague-Dawley fueron diariamente inyectadas por vía intraperitoneal, con CyA durante diez semanas. Las muestras de tejido renal de estos animales fueron examinadas a través de microscopía electrónica. Detalladas características estructurales han sido examinadas en los gránulos secretores de las células yuxtaglomerulares. Se ha observado una cantidad considerable de gránulos, que va con el proceso de exocitosis. Además, se encontaron células que habían secretado el contenido de sus gránulos de manera diferente. Esto fue interpretado como secreción de tipo diacrina. En conclusión, este estudio in vivo presenta evidencias morfológicas que demuestran que tanto la exocitosis y la secreción diacrina podría ocurrir en células JG. También tuvimos la oportunidad de observar probables gránulos secretores, que mostrarían "la secreción diacrina", que es muy difícil de visualizar, a nivel de microscopía electrónica. Este informe también proporciona la prueba morfológica que demuestra que estos dos mecanismos...

Anthropometric breast measurement: a study of 385 Turkish female students.

BACKGROUND: Anthropometric measurements and proportions of the human body have made a significant contribution to the science of aesthetic and reconstructive plastic surgery. OBJECTIVE: The present study was performed to measure anthropometric breast values in Turkish female students and compare them with those of women in other nations. METHODS: The study included 385 female undergraduate student volunteers between the ages of 18 and 26 years with no physical or developmental deformity and with a body mass index between 20 and 26. A total of 19 parameters were measured in a standing position. The parameters measured were body weight, height, shoulder width, upper chest width, middle chest width, lower chest width, waist width, hip width, clavicle-nipple length, sternal notch-nipple length, nipple-nipple length, upper arm length, medial mammary radius, lateral mammary radius, nipple-inframammary fold length, nipple diameter, areola diameter, nipple projection, and mammary projection. Breast volume, breast ptosis, and retracted nipple rates were also assessed. RESULTS: The mean breast volume was determined to be 407.2 +/- 263.6 cc. The mean values of the right and left breast volumes were calculated as 415.2 +/- 264.5 cc and 399.1 +/- 265.5 cc, respectively; the right breast volume was significantly greater than the left breast volume (P < .001). The ideal external view of the breasts with equal volume for both sides and no ptosis was observed in 35.1% of the volunteers. The percentage of women with unilateral or bilateral retracted nipple was 2.6%. CONCLUSIONS: The results of the present study will help in comparing the anthropometric breast values of young Turkish women with those of women in other countries. They may also be useful either in planning aesthetic and reconstructive breast surgery or in designing breast augmentation accessories and clothing.