Characterization of the spontaneous and gripping-induced immobility episodes on taiep rats

In 1989, we described a new autosomic-recessive myelin-mutant rat that develops a progressive motor syndrome characterized by tremor, ataxia, immobility episodes (IEs), epilepsy, and paralysis. taiep is the acronym of these symptoms. The rat developed a hypomyelination, followed by demyelination. At an age of 7-8 months, taiep rats developed IEs, characterized electroencephalographically by REM sleep-like cortical activity. In our study, we analyzed the ontogeny of gripping-induced IEs between 5 and 18 months, their dependence to light-dark changes, sexual dimorphism, and susceptibility to mild stress. Our results showed that IEs start at an age of 6.5 months, with a peak frequency between 8.5 and 9.5 months. IEs have two peaks, one in the morning (0800-1000 h) and a second peak in the middle of the night (2300-0100 h). Spontaneous IEs showed an even distribution with a mean of 3 IEs every 2 h. IEs are sexually dimorphic being more common in male rats. The IEs can be induced by gripping the rat by the tail or the thorax, but most of the IEs were produced by gripping the tail. Mild stress produced by i.p. injection of physiological saline significantly decreased IEs.These results suggested that IEs are dependent on several biological variables, which are caused by hypomyelination, followed by demyelization, which causes alterations in the brainstem and hypothalamic mechanisms responsible for the sleep-wake cycle regulation, producing emergence of REM sleep-like behavior during awake periods.     

Desmoplastic hairless hypopigmented nevus (DHHN). A distinct variant of giant melanocytic nevus

Desmoplastic hairless hypopigmented nevus (DHHN) is the name Ruiz-Maldonado et al. gave to a new variant of giant congenital melanocytic nevus characterized clinically by a hard ligneous consistency, absence of hair and progressive loss of pigment. Histologically, dermal fibrosis consistent with desmoplasia is a predominant feature. We describe a 6-year-old boy with a hard hairless pigmented congenital nevus involving the lumbosacral area, buttocks, perineum and scrotum. During the first years of life, the nevus showed a progressive reduction in colour, size and consistency. These changes continued until the age of four when a well-demarcated tumour appeared, within the nevus, on the right buttock. Resection of this outgrowth was performed. Histologically, nevus cells of normal appearance between thick collagen bundles were present. Immunostaining revealed S100 +, Vim +, HMB45--results. The nevus has continued to involute to date. An immune response against the melanocytes of the nevus may explain this type of evolution.     

Health-related quality-of-life of care-givers as a predictor of nursing-home placement of patients with dementia

Care-giver health-related quality-of-life (QoL) as a predictor of nursing-home placement of family-member patients with dementia was evaluated (using the SF-36 questionnaire) in 181 care providers (78% females; mean age 63 years) at the start and at the end of 12 months of follow-up. The patients and their carers were evaluated at home or at the local Primary Health-care Centers (n = 37) in the area of Barcelona (Catalunya, Spain). Data were evaluated using logistic regression analysis with nursing-home placement of patients as the main outcome measure, and the care-givers' QoL, demographic, medical, social and cognitive variables as covariates. The incidence rate of nursing-home placement was 10.5% (95%CI: 6.4-15.9). Carers of patients who had not been placed in a nursing home had better QoL scores, even after controlling for potential confounding factors. The adjusted odds ratio of being admitted to a nursing home was 6.4 (95%CI: 2.1-19.0) for patients cared-for by relatives who rated their health as being much worse compared with the previous year. The care-giver's poor health-related QoL significantly influenced rates of nursing-home admission of patients in their care.     

Adenosine A2A and dopamine D2 heteromeric receptor complexes and their function

The existence of A2A-D2 heteromeric complexes is based on coimmunoprecipitation studies and on fluorescence resonance energy transfer and bioluminescence resonance energy transfer analyses. It has now become possible to show that A2A and D2 receptors also coimmunoprecipitate in striatal tissue, giving evidence for the existence of A2A-D2 heteromeric receptor complexes also in rat striatal tissue. The analysis gives evidence that these heteromers are constitutive, as they are observed in the absence of A2A and D2 agonists. The A2A-D2 heteromers could either be A2A-D2 heterodimers and/or higher-order A2A -D2 hetero-oligomers. In striatal neurons there are probably A2A-D2 heteromeric complexes, together with A2A-D2 homomeric complexes in the neuronal surface membrane. Their stoichiometry in various microdomains will have a major role in determining A2A and D2 signaling in the striatopallidal GABA neurons. Through the use of D2/D1 chimeras, evidence has been obtained that the fifth transmembrane (TM) domain and/or the I3 of the D2 receptor are part of the A2A-D2 receptor interface, where electrostatic epitope-epitope interactions involving the N-terminal part of I3 of the D2 receptor (arginine-rich epitope) play a major role, interacting with the carboxyl terminus of the A2A receptor. Computerized modeling of A2A-D2 heteromers are in line with these findings. It seems likely that A2A receptor-induced reduction of D2 receptor recognition, G protein coupling, and signaling, as well as the existence of A2A-D2 co-trafficking, are the consequence of the existence of an A2A-D2 receptor heteromer. The relevance of A2A-D2 heteromeric receptor complexes for Parkinson's disease and schizophrenia is emphasized as well as for the treatment of these diseases. Finally, recent evidence for the existence of antagonistic A2A-D3 heteromeric receptor complexes in cotransfected cell lines has been summarized.     

Suicidal behavior in schizophrenia and depression: a comparison

The aim of this study was to compare the frequencies and suicide attempt characteristics in patients with schizophrenia (N = 25) and major depression in absence of schizophrenia (N = 107). There were no significant differences in attempt methods, but attempters with schizophrenia reported a lower number of life events influencing the attempt (2.0 vs. 2.6), less influence of life events on the attempt (42% vs. 83%) and lower GAF scores (36 vs. 50). Schizophrenia was not associated with higher impulsivity scores but with significantly more lethal attempts (40% vs. 29%) and with a trend toward (p = 0.08) higher scores in aggressive behavior history.     

Poroid hidradenoma

Poroid hidradenoma is a recently described variant of eccrine poroma. This neoplasm presents structural findings of hidradenoma (solid and cystic areas) and cytological characteristics of poromas (poroid and cuticular cells, the latter showing ductal differentiation). We present a case of poroid hidradenoma in a 74-year-old woman, who consulted her physician because of a nodular lesion on the left buttock.     

Subcutaneous sarcoidosis as the first manifestation of systemic disease

There are dermatological symptoms in up to 25% of patients with sarcoidosis, and the appearance of specific subcutaneous nodules as a manifestation of this entity is rare. They may even predate other manifestations of sarcoidosis. We present the case of a 38-year-old woman with asymptomatic subcutaneous nodules in the limbs, which corresponded to deep sarcoid granulomas in the histological study. She did not present with any extracutaneous indications. The imaging tests performed revealed right paratracheal adenopathies. This led to the diagnosis of sarcoidosis, in both its subcutaneous and pulmonary forms (stage I). Subcutaneous sarcoidosis is probably an underdiagnosed entity, as fewer than 40 cases are reflected in literature. Its value lies in the fact that it may be the first manifestation of extracutaneous or systemic sarcoidosis, which means that this form of sarcoidosis must be considered in the differential diagnosis of subcutaneous nodular lesions; close follow-up of these patients is also necessary.     

X-linked Emery-Dreifuss muscular dystrophy and vacuoles: an immunohistochemical characterization

We report a striking abundance of rimmed vacuoles in two brothers with X-linked Emery-Dreifuss muscular dystrophy (X-EDMD) confirmed by the absence of emerin at the muscular nuclear envelope and by genetic analysis showing a new 2-bp deletion in exon 6 of the STA gene at the Xq28 region. Immunohistochemical analysis of the vacuoles revealed expression of dystrophin but not of merosin in the sarcolemma of rimmed vacuoles and absence of amyloid and membrane attack complex (MAC) deposition either in vacuoles or muscle fibers. The presence of rimmed vacuoles can be a histopathological finding in X-EDMD, and the diagnosis should not be excluded in clinically well-defined EDMD patients because of this finding.