The kidney during hibernation and arousal from hibernation. A natural model of organ preservation during cold ischaemia and reperfusion.

BACKGROUND: During hibernation the kidney is in a hypothermic condition where renal blood flow is minimal and urine production is much reduced. Periodical arousal from hibernation is associated with kidney reperfusion at increasing body temperature, and restored urine production rate. METHODS: To assess the degree of structural preservation during such extreme conditions, the kidney cortex was investigated by means of electron microscopy in the dormouse Muscardinus avellanarius during winter hibernation, arousal from hibernation and the summer active period. RESULTS: Results show that the fine structure of the kidney cortex is well preserved during hibernation. In the renal corpuscle, a sign of slight lesion was the focal presence of oedematous endothelial cells and/or podocytes. Proximal convoluted tubule cells showed fully preserved ultrastructure and polarity, and hypertrophic apical endocytic apparatus. Structural changes were associated with increased plasma electrolytes, creatinine and urea nitrogen, and proteinuria. During the process of arousal the fine structure of the kidney cortex was also well maintained. CONCLUSION: These results demonstrate that dormice are able to fully preserve kidney cortex structure under extreme conditions resembling e.g. severe ischaemia or hypothermic organ storage for transplantation, and reperfusion. Elucidation of the mechanisms involved in such a natural model of organ preservation could be relevant to human medicine.

Nonenzymatic oxidation of trienoic fatty acids contributes to reactive oxygen species management in Arabidopsis.

In higher plants such as Arabidopsis thaliana, omega-3 trienoic fatty acids (TFAs), represented mainly by alpha-linolenic acid, serve as precursors of jasmonic acid (JA), a potent lipid signal molecule essential for defense. The JA-independent roles of TFAs were investigated by comparing the TFA- and JA-deficient fatty acid desaturase triple mutant (fad3-2 fad7-2 fad8 (fad3 fad7 fad8)) with the aos (allene oxide synthase) mutant that contains TFAs but is JA-deficient. When challenged with the fungus Botrytis, resistance of the fad3 fad7 fad8 mutant was reduced when compared with the aos mutant, suggesting that TFAs play a role in cell survival independently of being the precursors of JA. An independent genetic approach using the lesion mimic mutant accelerated cell death2 (acd2-2) confirmed the importance of TFAs in containing lesion spread, which was increased in the lines in which the fad3 fad7 fad8 and acd2-2 mutations were combined when compared with the aos acd2-2 lines. Malondialdehyde, found to result from oxidative TFA fragmentation during lesion formation, was measured by gas chromatography-mass spectrometry. Its levels correlated with the survival of the tissue. Furthermore, plants lacking TFAs overproduced salicylic acid (SA), hydrogen peroxide, and transcripts encoding several SA-regulated and SA biosynthetic proteins. The data suggest a physiological role for TFAs as sinks for reactive oxygen species.

Poor reward sensitivity and apathy after stroke: implication of basal ganglia.

OBJECTIVE: To examine the relationship between reward sensitivity and self-reported apathy in stroke patients and to investigate the neuroanatomical correlates of both reward sensitivity and apathy. METHODS: In this prospective study, 55 chronic stroke patients were administered a questionnaire to assess apathy and a laboratory task to examine reward sensitivity by measuring motivationally driven behavior ("reinforcement-related speeding"). Fifteen participants without brain damage served as controls for the laboratory task. Negative mood, working memory, and global cognitive functioning were also measured to determine whether reward insensitivity and apathy were secondary to cognitive impairments or negative mood. Voxel-based lesion-symptom mapping was used to explore the neuroanatomical substrates of reward sensitivity and apathy. RESULTS: Participants showed reinforcement-related speeding in the highly reinforced condition of the laboratory task. However, this effect was significant for the controls only. For patients, poorer reward sensitivity was associated with greater self-reported apathy (p < 0.05) beyond negative mood and after lesion size was controlled for. Neither apathy nor reward sensitivity was related to working memory or global cognitive functioning. Voxel-based lesion-symptom mapping showed that damage to the ventral putamen and globus pallidus, dorsal thalamus, and left insula and prefrontal cortex was associated with poorer reward sensitivity. The putamen and thalamus were also involved in self-reported apathy. CONCLUSIONS: Poor reward sensitivity in stroke patients with damage to the ventral basal ganglia, dorsal thalamus, insula, or prefrontal cortex constitutes a core feature of apathy. These results provide valuable insight into the neural mechanisms and brain substrate underlying apathy.

Arteriovenous malformation in meningothelial meningioma: case report.

An unusual association of a meningioma and an arteriovenous malformation is reported. A 68-year-old man developed left homonymous hemianopsia, left hemiparesis, and gaze palsy. Magnetic resonance imaging showed a right occipital mass lesion containing multiple signal-void areas with tubular and honeycomb appearance, suggesting a marked vascular component. An angiogram showed abnormal vasculature in the mass supplied by the posterior cerebral artery and a dural arteriovenous malformation on the tentorium. Neuropathological examination after total removal of the mass revealed a meningothelial meningioma including major portions of an arteriovenous malformation that extended from the dura and leptomeninges, through the meningioma, and into the occipital lobe, where the tumor was located.

The perception of touch and the ventral somatosensory pathway.

In humans, touching the skin is known to activate, among others, the contralateral primary somatosensory cortex on the postcentral gyrus together with the bilateral parietal operculum (i.e. the anatomical site of the secondary somatosensory cortex). But which brain regions beyond the postcentral gyrus specifically contribute to the perception of touch remains speculative. In this study we collected structural magnetic resonance imaging scans and neurological examination reports of patients with brain injuries or stroke in the left or right hemisphere, but not in the postcentral gyrus as the entry site of cortical somatosensory processing. Using voxel-based lesion-symptom mapping, we compared patients with impaired touch perception (i.e. hypoaesthesia) to patients without such touch impairments. Patients with hypoaesthesia as compared to control patients differed in one single brain cluster comprising the contralateral parietal operculum together with the anterior and posterior insular cortex, the putamen, as well as subcortical white matter connections reaching ventrally towards prefrontal structures. This finding confirms previous speculations on the 'ventral pathway of somatosensory perception' and causally links these brain structures to the perception of touch.

Atherosclerotic renal artery stenosis: update on management strategies.

Purpose of reviewAtherosclerotic renal artery stenosis (ARAS) usually occurs in patients at high risk of vascular disease, and is associated with increased mortality. The primary goals of ARAS treatment include the control of blood pressure (BP), the improved renal function, and the benefit on cardiovascular events. Although medical therapy remains the standard approach to the management of ARAS, percutaneous transluminal renal angioplasty (PTRA) revascularization can be a therapeutic option under certain conditions.Recent findingsRecent evidence confirms that ARAS increases cardiovascular risk, independent of BP and renal function. This suggests that revascularization might potentially improve overall prognosis, but no data are available currently. In cases of significant ARAS, the accepted indications for PTRA are uncontrollable hypertension, gradual or acute renal function decline with the use of agents blocking the renin-angiotensin-aldosterone system, and recurrent flash pulmonary edema. The key point of treatment success remains in all cases a careful patient selection.SummaryAlthough the atherosclerotic lesions of the renal arteries tend to progress over time, the anatomical lesion progression is not always associated with changes in BP. Furthermore, a poor correlation was noted between the degree of anatomic stenosis and glomerular filtration rate. The high cardiovascular risk warrants aggressive pharmacological treatment to prevent progression of the generalized vascular disorder. Ongoing trials will show whether PTRA revascularization has added, long-term effects on BP, renal function, and cardiovascular prognosis. With or without PTRA revascularization, medical therapy using antihypertensive agents, statins, and aspirin is necessary in almost all cases.

Emotional behavior in acute stroke : the Lausanne emotion in stroke study

Résumé : Objectif: Etudier les comportements émotionnels chez les patients ayant souffert d'un accident vasculaire cérébral (AVC) Contexte: Les modifications du comportement émotionnel après un AVC sont actuellement bien reconnues mais ont été très peu étudiées dans la phase aigüe de l'AVC. Méthode: Tous les patients présentant un AVC datant de moins de 24 heures ont été inclus prospectivement. Nous avons validé une échelle (the Emotional Behavior Index (EBI)), comprenant 38 qualificatifs, représentant la tristesse, l'agressivité, la désinhibition, l'adaptation, la passivité, l'indifférence et le déni. Les informations cliniques et radiologiques (CT et IRM) ont été obtenues par le biais de notre Registre des AVC. L'analyse statistique a été faite au moyen de tests uni- et multi-variés Résultats: Des 254 patients inclus, 40% présentaient de la tristesse, 49% de la passivité, 17% de l'agressivité, 53% de l'indifférence, 76% de la désinhibition, 18% un manque d'adaptation et 44% une réaction de déni. Plusieurs interactions statistiquement significatives ont été mises en évidence. En effet, la tristesse semble corréler à des antécédents d'alcoolisme (r = p< 0.037), au sexe féminin (r = p<0.028) et à la nature hémorragique de l'AVC (r = p<0.063). L'agressivité corrèle à des antécédents de troubles dépressifs (r = p<0.046) et à la nature hémorragique de l'AVC (r = p<0.06). Le déni corrèle plutôt au sexe masculin (r = p<0.035) et aux lésions hémorragiques (r = p<0.05). Le comportement émotionnel ne corrèle ni au degré et type d'atteinte neurologique, ni à la localisation de l'AVC mais une association entre Les lésions hémorragiques et un comportement agressif a été mis en évidence (p<0.001) de même qu'avec un manque d'adaptation (r = p<0.015), une certaine indifférence (r = p<0.018) et une réaction de déni (r = p<0.045). Conclusion: L'observation systématique des modifications du comportement émotionnel après un AVC suggère que les altérations émotionnelles sont indépendantes de la thymie et de l'atteinte physique et représentent donc probablement des séquelles à part entière de l'AVC. Abstract: Objective: To study emotional behaviors in an acute stroke population. Background: Alterations in emotional behavior after stroke have been recently recognized, but little attention has been paid to these changes in the very acute phase of stroke. Methods: Adult patients presenting with acute stroke were prospectively recruited and studied. We validated the Emotional Behavior Index (EBI), a 38-item scale designed to evaluate behavioral aspects of sadness, aggressiveness, disinhibition, adaptation, passivity, indifference, and denial. Clinical, historical, and imaging (computed tomography/magnetic resonance imaging) data were obtained on each subject through our Stroke Registry. Statistical analysis was performed with both univariate and multivariate tests. Results: Of the 254 patients, 40% showed sadness, 49% passivity, 17% aggressiveness, 53% indifference, 76% disinhibition, 18% lack of adaptation, and 44% denial reactions. Several significant correlations were identified. Sadness was correlated with a personal history of alcohol abuse (r = P < 0.037), female gender (r = P < 0.028), and hemorrhagic nature of the stroke (r = P < 0.063). Aggressiveness was correlated with a personal history of depression (r = P < 0.046) and hemorrhage (r = P < 0.06). Denial was correlated with male gender (r= P < 0.035) and hemorrhagic lesions (r = P < 0.05). Emotional behavior did not correlate with either neurologic impairment or lesion localization, but there was an association between hemorrhage and aggressive behavior (P < 0.001), lack of adaptation (r = P < 0.015), indifference (r = P < 0.018), and denial (r = P < 0.045). Conclusions: Systematic observations of acute emotional behaviors after stroke suggest that emotional alterations are independent of mood and physical status and should be considered as a separate consequence of stroke.

Leishmania (Viannia) lainsoni: occurrence of intracellular promastigote forms in vivo and in vitro

Experimental chronic (45-day-old) skin lesion in hamster hind foot induced by Leishmania (Viannia) lainsoni infection showed the presence of promastigote forms in the tissue, inside parasitophorous vacuoles, as assessed by transmission electron microscopy. Experimental in vitro interaction (24 and 48 h) between Leishmania (V.)lainsoni and J774-G8 macrophage cells also demonstrated the same profile. This morphological aspect is unusual, since in this parasite genus only amastigote forms have been described as the resistant and obligate intracellular forms.

Oral mucosal melanoma: conservative treatment including laser surgery.

Objective: To discuss the convenience of laser surgery as optimal treatment for melanoma of the oral mucosa.Patients and methods: A retrospective evaluation of four patients with primary oral melanomas treated at a single Cancer Institution in Mexico City.Results: Two patients were treated with resection of the melanoma with CO2 laser together with extraction of the involved dental organs and curettage of the alveolar walls. These two cases had melanoma in situ with multiple isolated foci. The third patient had a lesion with vertical growth, who was submitted to partial maxillectomy along with selective dissection of bilateral neck levels I-V with a negative report and the fourth patient had a history of oral nodular melanoma and presented with lymph node metastasis. According to follow-up status, there was no distant metastasis in any of the patients reported here.Conclusion: In our experience, conservative management with CO2 laser is adequate for melanomas of the oral mucosa with extraction of the dental organs and curettage of the alveoli to achieve complete surgical resection microscopically without sacrifice of the quality of life. Management of the neck is controversial. We recommend selective therapeutic resection of the neck only if it is found to be clinically positive. Elective dissection has not shown to have an impact in overall survival.

The girl from the Church of the Sacrament: a case of congenital syphilis in XVIII century Lisbon

Syphilis is a sexually or congenitally transmitted infectious disease with an impact on the health of human populations that has undergone important cycles in different countries and periods of history. Its presence was first diagnosed in Europe in the late XIV century. In Portugal, although there are various written records of the infection in the last centuries, there are rare references to it in archeological findings (mummified bodies are also rare in Portugal). The current study describes a probable case of congenital syphilis in an 18-month-old girl buried in the Church of the Sacrament in Lisbon. Her body, dating to the XVIII century, was found mummified together with dozens of others, still not studied. Symmetrical periostitis of the long bones, osteitis, metaphyseal lesions, left knee articular, and epiphyseal destruction, and a rarefied lesion with a radiological appearance compatible with Wimberger's sign all point to a diagnosis of congenital syphilis. The diagnosis of this severe form of the infection, possibly related to the cause of death in this upper-class girl, calls attention to the disease's presence in XVIII century Lisbon and is consistent with the intense mobilization at the time in relation to the risks posed by so-called heredosyphilis. It is the first case of congenital syphilis in a child reported in archeological findings in Portugal, and can be correlated with other cases in skeletons of adults buried in cemeteries in Lisbon (in the XVI to XVIII centuries) and Coimbra (XIX century). Finally, this finding highlights the need to study the entire series of mummified bodies in the Church of the Sacrament in order to compare the paleopathological findings and existing historical documents on syphilis, so as to expand the paleoepidemiological knowledge of this infection in XVIII century Lisbon.

Broken noses for the gods: ritual battles in the Atacama Desert during the Tiwanaku period

The sample consists of 226 skulls from the Atacameño cemetery of Coyo Oriente (639-910 AD), associated with the Tiwanaku period. The authors analyzed signs of acute trauma typically associated with violence, and the results were 12% of men and 9.9% of women displaying any type of lesion related to violence. In males, concentration of these non-lethal lesions in the nasal region (10.4%) as opposed to a random distribution over the entire skull (1.6%), suggests that the blows were struck during rituals. The cultural context of this period, with a strong ideological influence from Tiwanaku, supports the ritual hypothesis, since both the ethnographic as well as archeological records point to the existence of non-lethal violent bleeding with ritual beating to the face. Such rituals persist to this day among certain Andean populations. Among women, the most plausible hypothesis for the lesions (3.9% in the skull, 4.9% in the nasal bones, and 0.9% in the face) is domestic conflicts, since they show a random distribution. Previous studies with other Atacameño samples had indicated the same results for women.

Caries prevalence in skeletal series: is it possible to compare?

Because of the relationship with subsistence, dental caries is a central issue in paleopathological research. Usually, comparisons between caries prevalence exhibited in different skeletal series are made. Dietary variation is the most common explanation for cavities prevalence. The aim of this paper is to verify if it is possible to compare caries prevalence reported on papers for archaeological skeletal series. Another goal is to determine if other factors besides diet are implicated in dental cavity prevalence explanation. Twenty six papers about dental health with caries prevalences published from 1999 to 2004 were analyzed for completeness. This assessment includes carious lesion diagnosis and characteristics, age, sex and size characteristics of samples, and prevalence calculation method. The majority of the analyzed papers do not provide adequate information in the topics listed above. Only very few implicated factors other than diet as a contributor to caries lesions development.

Interferon-gamma is required for the late but not early control of Leishmania amazonensis infection in C57Bl/6 mice

The critical role of interferon-gamma (IFN-g) in the resistance of C57Bl/6 mice to Leishmania major is widely established but its role in the relative resistance of these animals to L. amazonensis infection is still not clear. In this work we use C57Bl/6 mice congenitally deficient in the IFN-g gene (IFN-g KO) to address this issue. We found that IFN-g KO mice were as resistant as their wild-type (WT) counterparts at least during the first two months of infection. Afterwards, whereas WT mice maintained lesion growth under control, IFN-g KO mice developed devastating lesions. At day 97 of infection, their lesions were 9-fold larger than WT controls, concomitant with an increased parasite burden. At this stage, lesion-draining cells from IFN-g KO mice had impaired capacity to produce interleukin-12 (IL-12) and tumour necrosis factor-a in response to parasite antigens whereas IL-4 was slightly increased in comparison to infected WT mice. Together, these results show that IFN-g is not critical for the initial control of L. amazonensis infection in C57Bl/6 mice, but is essencial for the developmente of a protective Th1 type immune response in the later stages.

Prevalence of oral hairy leukoplakia and epithelial infection by Epstein-Barr virus in pregnant women and diabetes mellitus patients: cytopathologic and molecular study

Oral hairy leukoplakia (OHL) is generally reported in patients with severe immunosuppression, except for a few cases in individuals with moderate degree of immunodeficiency. It is a white lesion that appears mainly in the lateral border of the tongue, caused by Epstein-Barr virus (EBV). The nuclear changes caused by EBV (Cowdry A inclusion, ground glass and nuclear beading), observed in cytopathology, are specific and enough for the definitive diagnosis of OHL, independent of the identification of the virus. Here we investigated the prevalence of OHL and the presence of EBV-DNA in the lateral borders of the tongue from 90 pregnant women, 90 diabetes mellitus (DM) patients, 30 healthy individuals (negative group) and 30 HIV+ with OHL (positive group). Smears were analyzed by cytopathology and polymerase chain reaction (PCR). A case of subclinical OHL and candidiasis was identificated in a DM patient by cytopathologic analysis. PCR results demonstrated EBV-DNA in 65% of the pregnant women, in 35% of DM patients, and in 20% of the healthy individuals. We concluded that DM patients can develop OHL with a low prevalence. Furthermore, the prevalence of the EBV in lateral border of the tongue is larger in pregnant women than in healthy individuals.

Factors affecting cognitive outcome in early pediatric stroke.

OBJECTIVE: We examined cognitive performance in children after stroke to study the influence of age at stroke, seizures, lesion characteristics, neurologic impairment (NI), and functional outcome on cognitive outcome. METHODS: This was a prospectively designed study conducted in 99 children who sustained an arterial ischemic stroke (AIS) between the age of 1 month and 16 years. All children underwent cognitive and neurologic follow-up examination sessions 2 years after the insult. Cognitive development was assessed with age-appropriate instruments. RESULTS: Although mean cognitive performance was in the lower normative range, we found poorer results in subtests measuring visuoconstructive skills, short-term memory, and processing speed. Risk factors for negative cognitive outcome were young age at stroke, seizures, combined lesion location (cortical and subcortical), as well as marked NI. CONCLUSIONS: We recommend that all children with a history of AIS undergo regularly scheduled neuropsychological assessment to ensure implementation of appropriate interventions and environmental adjustments as early as possible.