Light microscopy morphological characteristics of the sperm flagellum may be related to axonemal abnormalities

Although electron microscopy provides a detailed analysis of ultrastructural abnormalities, this technique is not available in all laboratories. We sought to determine whether certain characteristics of the flagellum as assessed by light microscopy were related to axonemal abnormalities. Forty‐one patients with an absence of outer dynein arms (type I), a lack of a central complex (type III) and an absence of peripheral doublets (type IV) were studied. Sperm morphology was scored according to David's modified classification. Flagella with an irregular thickness were classified as being of normal length, short or broken. There were correlations between missing outer dynein arms and abnormal, short or coiled flagellum. Type III patients showed the highest flagellar defects (a short (P = 0.0027) or an absent flagellum (P = 0.011)). Just over 68% of the irregular flagella were short in Type III patients, whereas this value was only 34.5% in type I and 26.4% in type IV (P = 0.002). There was a negative correlation between misassembly and spermatozoa of irregular flagella (r = ?0.79; P = 0.019). It is concluded that light microscopy analysis of flagellum abnormalities may help provide a correct diagnosis, identify sperm abnormalities with fertility potentials and outcomes in assisted reproduction technologies and assess the genetic risk.     

Pneumothorax-associated pleural eosinophilia is tumour necrosis factor-alpha-dependent and attenuated by steroids

Background and objectives: The pathogenesis and the optimal treatment of eosinophilic pleural effusions are unknown. We aimed to examine whether pneumothorax‐associated pleural eosinophilia in mice is dependent on tumour necrosis factor (TNF)‐alpha, and whether it is affected by systemic administration of corticosteroids. Methods: Mice were injected intrapleurally with 0.4 mL air to create pneumothoraces. Animals were sacrificed 24 or 48 h later, and pleural lavage (PL) was performed. In the first experiment, comparisons were made between wild‐type and TNF‐α knockout mice with pneumothorax. In the second experiment, wild‐type mice were injected intraperitoneally with different doses of dexamethasone (0, 0.25, 0.5 and 1 mg/kg), 5 min before and 24 h after the induction of pneumothorax. Results: After induction of a pneumothorax, TNF‐α knockout mice had significantly fewer total number of cells (P = 0.004), mononuclear cells (P = 0.01), neutrophils (P = 0.017) and eosinophils (P = 0.002) in their PL compared with wild‐type animals. TNF‐α was detected in the PL of most of the control mice but not in TNF‐α knockouts. Dexamethasone induced a significant, dose‐dependent reduction of PL total cells (P < 0.001), eosinophils (P < 0.001), mononuclear cells (P = 0.007) and lymphocytes (P = 0.04) at 48 h, and significantly reduced the number of PL total cells (P = 0.045) and eosinophils (P = 0.005) at 24 h. Furthermore, dexamethasone prevented eosinophil infiltration of lung and pleural tissue. Conclusion: Pneumothorax‐associated pleural eosinophilia in mice is TNF‐α‐dependent and is significantly attenuated by corticosteroid treatment. In addition, both TNF‐α deficiency and dexamethasone treatment were associated with a significant reduction of other types of inflammatory cells in PL.     

Immunodetection of Tau microtubule-associated protein in human sperm and testis

Dear Editor,
The cytosolic protein Tau is naturally present in human neurons, where it has a pivotal role in controlling microtubule stability. Hyperphosphorylation of Tau （observed during neurodegenerative diseases, such as Alzheimer＇s disease） impairs the protein＇s ability to bind microtubules. This results in microtubule disassembly and the formation of Tau aggregates, Tau protein is also widely expressed in peripheral tissues. In the male reproductive system, screening for Tau has focused solely on the rodent and bovine testis. In the present study, we used immunofluorescence and immunoenzymatic techniques （with a Tau-specific antibody） to investigate the presence of Tau protein in human ejaculated sperm and testicular tissue.     

The Dose-Response Effects of Consuming High Fructose Corn Syrup-Sweetened Beverages on Hepatic Lipid Content and Insulin Sensitivity in Young Adults

Increased hepatic lipid content and decreased insulin sensitivity have critical roles in the development of cardiometabolic diseases. Therefore, our objective was to investigate the dose-response effects of consuming high fructose corn syrup (HFCS)-sweetened beverages for two weeks on hepatic lipid content and insulin sensitivity in young (18–40 years) adults (BMI 18–35 kg/m²). In a parallel, double-blinded study, participants consumed three beverages/day providing 0% (aspartame: n = 23), 10% (n = 18), 17.5% (n = 16), or 25% (n = 28) daily energy requirements from HFCS. Magnetic resonance imaging for hepatic lipid content and oral glucose tolerance tests (OGTT) were conducted during 3.5-day inpatient visits at baseline and again at the end of a 15-day intervention. During the 12 intervening outpatient days participants consumed their usual diets with their assigned beverages. Significant linear dose-response effects were observed for increases of hepatic lipid content (p = 0.015) and glucose and insulin AUCs during OGTT (both p = 0.0004), and for decreases in the Matsuda (p = 0.0087) and Predicted M (p = 0.0027) indices of insulin sensitivity. These dose-response effects strengthen the mechanistic evidence implicating consumption of HFCS-sweetened beverages as a contributor to the metabolic dysregulation that increases risk for nonalcoholic fatty liver disease and type 2 diabetes.     

Retroperitoneal perforation of a duodenal diverticulum with colonic necrosis -- report of a case

Primary duodenal diverticula are usually asymptomatic. About 115 perforations have been reported, but none with right colon necrosis. We report a 45-year-old woman, with a five days history of high fever along with epigastric and periumbilical pain. Physical examination revealed right upper and lower quadrant tenderness with peritoneal signs. White blood cell count was 11 500/mm (3) while biochemical and hepatic biology tests were normal. Abdominal radiographs showed no pathologic findings. Ultrasound disclosed fluid in the lower pelvis. Computerized tomography revealed fluid collection in the right hepatorenal space. Intraoperative findings included purulent fluid in the lower pelvis, segmental necrotic changes of the right colon, and a perforated diverticulum on the antimesenteric border of the third part of the duodenum. Surgery consisted of right hemicolectomy and ileo-transverse anastomosis, diverticulectomy, and decompressive lateral duodenostomy at the second duodenal portion. The patient had an uneventful postoperative course. A contrast study from the duodenostomy tube on the 6 (th) postoperative day showed no leakage or obstruction. Duodenostomy tube was removed on the 14 (th) postoperative day. Histology confirmed the diagnosis of a primary duodenal diverticulum.     

Visual categorization and object representation in monkeys and humans

We investigated the influence of a categorization task on the extraction and representation of perceptual features in humans and monkeys. The use of parameterized stimuli (schematic faces and fish) with fixed diagnostic features in combination with a similarity-rating task allowed us to demonstrate perceptual sensitization to the diagnostic dimensions of the categorization task for the monkeys. Moreover, our results reveal important similarities between human and monkey visual subordinate categorization strategies. Neither the humans nor the monkeys compared the new stimuli to class prototypes or based their decisions on conditional probabilities along stimulus dimensions. Instead, they classified each object according to its similarity to familiar members of the alternative categories, or with respect to its position to a linear boundary between the learned categories.     

Relationship between iNOS expression and aortic cell proliferation and apoptosis in an elastase-induced model of aorta aneurysm and the effect of 1400 W administration

BACKGROUND: In the present study, we employed an elastase infusion-dependent abdominal aortic aneurysm (AAA) model to examine inducible nitric oxide synthase (iNOS) expression in relation to cellular proliferation and apoptosis in this pathologic condition. Furthermore, we employed N-(3-(aminomethyl)benzyl)acetamidine (1400 W), a previously shown selective iNOS inhibitor, to further explore this relationship. METHODS: Adult male Wistar rats were randomized into separate groups. Group A served as a control and received an intra-aortic saline infusion, while groups B, C, and D received an intra-aortic elastase infusion according to standard protocols. The animals in group C were administered postoperatively the highly selective iNOS inhibitor, 1400 W, while rats in group D received regularly the same compound preoperatively and postoperatively. The animals were killed at postoperative days 7 and 14. Aorta diameter and nitric oxide (NO), nitrite/nitrate, and MDA levels were measured. iNOS expression was assessed by immunohistochemistry and Western blot analysis, while Ki-67 immunohistochemistry and TUNEL assay were used to evaluate cellular proliferation and apoptosis, respectively. RESULTS: Increased iNOS and NO levels accompanied aneurysm development in groups B, C, and D, but these levels were significantly lower in groups C and D, compared with group B. Interestingly, very low but detectable levels of iNOS were found in the control group, indicating a basal constitutive level. Cell growth parameters were augmented in group B compared with group A. In contrast, groups C and D exhibited a significant decrease of the cellular growth parameters but did not attain normal values. CONCLUSIONS: iNOS-derived NO is associated with the cellular growth parameters of the vessel cells, predominantly smooth muscle cells. Selective iNOS blockage ameliorates the cellular remodeling in AAAs.     

Visual categorization and the inferior temporal cortex

We investigated the effects of categorization on the representation of stimulus features in combined psychophysical-electrophysiological experiments. We used parameterized line drawings of faces and fish as stimuli, and we varied the relevance of the different features for the categorization task. The psychophysical and electrophysiological data support an exemplar-based framework for visual object recognition. We recorded from visual neurons in the anterior inferior temporal (IT) cortex of macaque monkeys, while they were performing a categorization task. The visual neurons did not respond selectively to one stimulus set, or to one category. The majority of the anterior IT feature selective neurons were tuned for features that were diagnostic for the categorization task. We argue that this fine-tuning of the neurons reflects the perceptual sensitization to the diagnostic features.     

Vascular endothelial growth factor and matrix metalloproteinase 9 expression in human carotid atherosclerotic plaques: relationship with plaque destabilization via neovascularization

BACKGROUND: The aim of this study was to evaluate the potential impact of vascular endothelial growth factor (VEGF) on carotid plaque destabilization in association with matrix metalloproteinase 9 (MMP-9) production. METHODS: Expression of VEGF and MMP-9 were determined immunohistochemically in 53 human endarterectomized atherosclerotic carotid plaques. The relationship to carotid plaque characteristics, clinical data and histological morphology was investigated. RESULTS: VEGF and MMP-9 had parallel overexpression in the inflammatory cells, especially in the neovascularized plaque lesions and around the cholesterol crystals. Strong expression of VEGF was evident in symptomatic patients (p < 0.057), in high-degree stenosis (p = 0.005), and in patients with ischemic infarct in brain scan (p = 0.021). No relation was proved between molecule expression and plaque ultrasonic characteristics. CONCLUSIONS: An intense expression of VEGF and MMP-9 in carotid plaques is related to plaque instability, high degree of stenosis and presence of symptomatic carotid occlusive disease.