The saturated fatty acid palmitate induces human monocytic cell toxicity toward neuronal cells: exploring a possible link between obesity-related metabolic impairments and neuroinflammation

Obesity is linked to increased risk of Alzheimer's disease and cognitive impairment. Microglia-mediated neuroinflammation is implicated in neuronal loss. Elevated levels of fatty acids seen in obesity induce inflammation in peripheral tissues. Whether fatty acids promote neuroinflammation is unknown. Using an established neuroinflammation model involving human microglia-like THP-1 cells and SH-SY5Y neuroblastoma cells, we show that the saturated fatty acid palmitate, but not the unsaturated fatty acids oleate or linoleate, induces THP-1 cell pro-inflammatory cytokine secretion and neurotoxicity. Inhibition of c-Jun NH2-terminal kinase (JNK) reduces this neurotoxicity. Therefore, elevated saturated fatty acids may induce neuroinflammation through pathways involving JNK activation.     

Postsurgical infection after myelomeningocele repair: a multivariate analysis of 60 consecutive cases

Objective

We investigate the demographic, clinical and surgical variables associated with wound and ventriculoperitoneal (VP) shunt infections in a well-defined group of patients submitted to neurosurgical myelomeningocele repair.

Methods

We analyzed the data of sixty consecutive patients with a myelomeningocele diagnosis submitted to neurosurgical repair between January 2002 and December 2005. Multiple logistic regression analysis identified clinical, demographic and neurosurgical variables that were independently associated with the occurrence of wound and VP shunt infections.

Results

Seven patients (11.7%) developed wound infections after myelomeningocele repair and two (3.3%) presented with sepsis unrelated to the neurosurgical procedures. Forty-six patients (76.7%) received a VP shunt and nine of them (19.6%) had VP shunt infection. There was a non-significant trend (p = 0.09) for a higher association between thoracic than lumbar or sacral topography and the occurrence of any type of infection. Among patients who underwent VP shunt placement, there was a non-significant trend for a higher association between VP shunt infection and thoracic topography compared to lumbar or sacral regions (adjusted OR 4.3; CI 95% 0.7–24.7; p = 0.10). Evans’ index scores higher than 70 were ten times more associated with VP shunt infection (adjusted OR 10.5; CI 95% 1.6–67.4; p = 0.01) than lower scores.

Conclusion

The thoracic topography of myelomeningocele has a trend for a higher association with infection in general and VP shunt infection. Evans’ index scores higher than 70 were independently associated with VP shunt infection.     

Sex steroid hormones regulate the expression of growth-associated protein 43, microtubule-associated protein 2, synapsin 1 and actin in the ventromedial nucleus of the hypothalamus

The ventromedial nucleus of the hypothalamus is well known for its involvement in the regulation of the female reproductive behavior. The dendritic trees of neurons in its ventrolateral division (VMNvl), the dendritic spines, and the dendritic and spine synapses undergo alterations along the estrous cycle. Because these changes are conspicuous, we thought of interest to examine the influence of sex steroids in the levels of the structural proteins of axons and dendrites. The VMNvl of female rats at all phases of the estrous cycle was labeled for growth-associated protein-43, microtubule-associated protein 2, synapsin 1 and actin. The intensity of the labeling was measured using a modified Brightness–Area–Product method that is sensitive to variations the size of the VMN. The brightness per unit area of these proteins did not undergo significant variations over the estrous cycle, except synapsin 1 that was significantly reduced in diestrus relative to the remaining phases of the ovarian cycle. Conversely, the Brightness–Area–Product of all labeled proteins changed along the estrous cycle and was greater at proestrus than at all other phases. Our results show the presence of estrous cycle-related oscillations in the levels of the structural proteins that are involved in dendritic and synaptic plasticity.     

Listeria monocytogenes peritonitis in cirrhotic patients: first description in Brazil

Two cases of spontaneous bacterial peritonitis (SBP) caused by Listeria monocytogenes in cirrhotic patients are reported. In one of the cases, the microorganism was isolated from pleural effusion and ascites. SBP is a serious and common complication of patients with ascites caused by hepatic cirrhosis and the culture of the ascitic fluid is an important tool for the diagnosis and for the more appropriate treatment. Although a third generation cephalosporin has usually been employed for empiric treatment of SBP, it does not provide adequate coverage against Listeria spp. In such cases the use of ampicillin (with or without sulbactam) or sulfamethoxazole-trimethoprim is recommended. The last one is used for secondary prophylaxis, instead of norfloxacin. To summarize, Listeria monocytogenes infection is a rare cause of SBP, whose treatment should be specific for the bacteria.     

Otosclerosis of the incus.

OBJECTIVE: To report a case of a patient with otosclerosis of the incus. PATIENTS: A 61-year-old woman with a progressive hearing loss on her left ear and a computed tomographic scan of the temporal bone revealing an expansible lesion of the incus. INTERVENTIONS: The ossicle was removed by using a transtympanomastoid approach; the ossicular chain was reconstructed using a titanium partial ossicular replacement prosthesis. MAIN OUTCOME MEASURE: The diagnosis of the disease was obtained by means of histopathologic examination of the specimen. RESULTS: The patient obtained a good postoperative hearing result. The histopathologic examination of the specimen documented an otosclerosis of the incus. CONCLUSION: Otosclerotic involvement of the middle ear ossicles, apart from footplate, was very rarely mentioned. Most subjects were incidentally diagnosed postmortem by means of examination of specimens from temporal bone collections. The diagnosis and treatment of a patient with otosclerosis of the incus is exceptional; however, otosclerosis should be considered in the differential diagnosis of expansible lesions of the ossicles.