<div> <div> <div> <p>Recent observations of short-term changes in the neural health of youth athletes participating in collision sports such as football (boys) and soccer (girls) have incited a need to explore structural alterations in their brain tissue volumes. Studies have shown biochemical, vascular, functional connectivity, and white matter diffusivity changes in the brain physiology of these athletes that are strongly correlated with repetitive head acceleration exposure from on-field collisions. Here, research is presented that highlights regional anatomical volumetric measures that change longitudinally with accrued repetitive head impacts. A novel pipeline is introduced that provides simplified data analysis on a standard-space template to quantify group-level longitudinal volumetric changes within these populations. For both sports, results highlight incremental relative regional volumetric changes in the sub-cortical cerebrospinal fluid that are strongly correlated with head exposure events greater than a 50G threshold at the short-term post-season assessment. Moreover, longitudinal regional gray matter volumes are observed to decrease with time, only returning to baseline/pre-participation levels after sufficient (5-6 months) rest from collision-based exposure. These temporal structural volumetric alterations are significantly different from normal aging observed in gender and age-matched controls participating in non-collision sports. Future work involves modeling safe repetitive head exposure thresholds with multimodal image analysis and understanding their underlying physiological functioning. A possible pathophysiological pathway is presented highlighting the probable metabolic regulatory mechanisms. The interdisciplinary nature of this work is crucial to understand this pathology accurately and aid healthcare, sport professionals in the future. It is evident that continual participation in collision- based activities may represent a risk wherein recovery cannot occur. Even when present, the degree of the eventual recovery remains to be explored but has strong implications for the well-being of collision-sport participants. </p> </div> </div> </div>

The basic examination of the cerebrospinal fluid provides a quick orientation in the diagnostic algorithm of CNS diseases about the nature of the pathological process. The current evaluation of cytology and biochemical parameters of glucose metabolism reports about the cells present and at the same time about the level of their activation. The aim of the work was to investigate the relationship between biochemical and cytological findings in cerebrospinal fluid in a large data set (n = 8 178), or confirm the hypothesis of a significant alteration in the Coefficient of Energy Balance (CEB) in cytological classes typically accompanying oxidative burst of phagocytes. CEB was subjected to analysis and comparison with other energy parameters (lacto-glucose ratio, gluco-lactate ratio, concentration of lactate and glucose in cerebrospinal fluid). The relationships between blood and cerebrospinal fluid glucose and lactate concentrations were investigated. CEB values were statistically significantly different in cytological groups, which reflected purulent inflammation, tumor involvement or infection by potential intracellular pathogens, the hypothesis was confirmed. Other energy parameters excluding glycorrhachia distinguish these cytological groups as well as CEB. There are inaccuracies in the derivation...

As the aging population is increasing worldwide, so is the prevalence of neurodegenerativediseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), frontotemporal dementia(FTD) and amyotrophic lateral sclerosis (ALS). Reliable biomarkers able to aid the diagnosis anddifferentiation of these diseases are needed in order to start the right treatment as early as possible.Due to its representative state of the central nervous system, cerebrospinal fluid (CSF) is afavorable sample material for biomarker discovery within neurodegenerative diseases. Alteredprotein levels of this body fluid might serve as a biomarker, but further validation of earlierfindings is needed. The aim of this project was to validate earlier studies suggesting potentialprotein biomarkers in CSF. From a list of 80 potential biomarkers in the CSF of patient samples,eight were chosen to be included in this validation effort. By utilizing a suspension bead array ina sandwich assay setup, 21 antibodies were tested in an initial screening. Antibody pairs that couldmeasure the protein levels in a dilution dependent manner was further optimized before individualpatient samples were analyzed. Sandwich assays targeting the three proteins Amphiphysin(AMPH), Chitotriosidase-1 (CHIT1) and Beta-synuclein (SNCB) were successfully developed andcorrelated to earlier generated data using a suspension bead array with a single binder setup.Therefore, the earlier findings of elevated levels of AMPH and SNCB in AD patients and CHIT1in ALS patients were successfully validated. / Prevalensen av neurodegenerativa sjukdomar såsom Alzheimers sjukdom (AD), Parkinsonssjukdom (PD), frontallobsdemens (FTD) och amyotrofisk lateralskleros (ALS) ökar i takt med denåldrande populationen. Pålitliga biomarkörer som kan hjälpa till vid diagnostiseringen av dessasjukdomar behövs för att starta rätt behandling så tidigt som möjligt. Ryggmärgsvätska, enkroppsvätska tillhörande det centrala nervsystemet, kan ge en inblick i det centrala nervsystemetstillstånd. Förändrade proteinnivåer i denna kroppsvätska skulle därför kunna fungera sombiomarkörer. Målet i detta projekt var att validera tidigare föreslagna proteinbiomarkörer iryggmärgsvätska. Utifrån en lista av 80 tidigare analyserade proteiner i ryggmärgsvätska hospatienter, inkluderades åtta proteiner i detta valideringsförsök. En antikroppsbaserad så kalladsandwich assay användes i en suspension bead array för att testa 21 stycken antikroppar i ett initialtscreeningsförsök. Antikroppspar som kunde mäta proteinnivåer på ett spädningsberoende vis i detinitiala screeningsförsöket optimerades vidare innan den utvecklade sandwich assayn användes föratt analysera proteinnivåer i individuella prover. Sandwich assays gentemot Amphiphysin(AMPH), Chitotriosidase-1 (CHIT1) och Beta-synuclein (SNCB) kunde bli framtagna ochkorrelerade gentemot tidigare genererat data från en single binder assay på ett framgångsrikt sätt.Projektet kunde därmed validera tidigare fynd som indikerat förhöjda nivåer av AMPH och SNCBi AD patienter, samt förhöjda nivåer av CHIT1 i ALS patienter.

Streptococcus suis (S. suis) is an important opportunistic pathogen, which can cause septicemia and meningitis in pigs and humans. Previous in vivo observations in S. suisinfected pigs revealed lesions at the choroid plexus (CP). In vitro experiments with primary porcine CP epithelial cells (PCPEC) and human CP epithelial papilloma (HIBCPP) cells demonstrated that S. suis can invade and traverse the CP epithelium, and that the CP contributes to the inflammatory response via cytokine expression. Here, next generation sequencing (RNA-seq) was used to compare global transcriptome profiles of PCPEC and HIBCPP cells challenged with S. suis serotype (ST) 2 infected in vitro, and of pigs infected in vivo. Identified differentially expressed genes (DEGs) were, amongst others, involved in inflammatory responses and hypoxia. The RNA-seq data were validated via quantitative PCR of selected DEGs. Employing Gene Set Enrichment Analysis (GSEA), 18, 28, and 21 enriched hallmark gene sets (GSs) were identified for infected HIBCPP cells, PCPEC, and in the CP of pigs suffering from S. suis ST2 meningitis, respectively, of which eight GSs overlapped between the three different sample sets. The majority of these GSs are involved in cellular signaling and pathways, immune response, and development, including inflammatory response and hypoxia. In contrast, suppressed GSs observed during in vitro and in vivo S. suis ST2 infections included those, which were involved in cellular proliferation and metabolic processes. This study suggests that similar cellular processes occur in infected human and porcine CP epithelial cells, especially in terms of inflammatory response.

This work aims to contribute to the lack of computational methods for medical image analysis and diagnosis about the study of cerebrospinal fluid volumes. In the first part, we focus on the volume assessment of the fluid spaces, from whole body images, in a population consisting of healthy adults and hydrocephalus patients. To help segmentation, these images, obtained from a recent "tissue-specific" magnetic resonance imaging sequence, highlight cerebrospinal fluid unlike its neigh borhood structures. We propose automatic segmentation and separation methods of the different spaces, which allow efficient and reproducible quantification. We show that the ratio of the total subarachnoid space volume to the ventricular one is a proportionality constant for healthy adults, to support a stable intracranial pressure. However, this ratio decreases and varies significantly among patients suffering from hydrocephalus. This ratio provides a reliable physiological index to help in the diagnosis of hydrocephalus. The second part of this work is dedicated to the fluid volume distribution analysis within the superior cortical subarachnoid space. Anatomical complexity of this space induces that it remains poorly studied. We propose two complementary methods to visualize the fluid volume distribution, and which both produce two-dimensional images from the original ones. These images, called relief maps, are used to characterize respectively, the fluid volume distribution and the fluid network, to classify healthy adults and patients with hydrocephalus, and to perform patient monitoring before and after surgery

Résumé : Introduction: À ce jour, notre compréhension des mécanismes neurophysiologiques responsables du développement d'une douleur chronique est encore relativement limitée. Il est proposé que certaines modifications dans l'efficacité des mécanismes endogènes d'inhibition descendante de la douleur pourraient contribuer à ce phénomène. Considérant l'importance de la neurotransmission monoaminergique dans les mécanismes descendants de modulation de la douleur, autant inhibiteur que facilitateur, nous émettons l'hypothèse que la persistance temporelle d'une douleur peut provoquer des modifications dans la fonctionnalité des deux systèmes majeurs (sérotoninergique et noradrénergique) sous-jacents à ces mécanismes de contrôle endogène, participant ainsi à la dynamique de développement et à la progression des états de douleur chronique à travers le temps. Objectif général: En utilisant une approche translationnelle, nous avons exploré l'association entre la fonctionnalité (centrale & périphérique) des systèmes de neurotransmission monoaminergique et l'efficacité des mécanismes descendants d’inhibition pendant le développement et la progression d'une douleur chronique. Résultats cliniques: D'une part, nos résultats répliquent plusieurs observations de la littérature ayant démontré une diminution de l'efficacité des mécanismes descendants d’inhibition de la douleur (à l'aide d'un paradigme de modulation conditionnée de la douleur; MCD) chez des sujets souffrant de douleur musculosquelettique chronique (sujets CP). Chez ces mêmes sujets, nous observons également une diminution des concentrations plasmatiques basales en noradrénaline (NA) et métanéphrine, lorsque comparés à des sujets sains (sujets PF). Pour tous les sujets testés (PF et CP), une association positive est mise en évidence entre l'efficacité de la MCD et les concentrations plasmatiques basales en NA et métanéphrine. Par conséquent, ces concentrations des catécholamines dans le plasma pourraient servir d'indicateurs moléculaires de l'efficacité latente de la MCD. Par ailleurs, aucune différence dans l'activité monoaminergique et aucune association avec l'efficacité de la MCD n'ont été observées au niveau du liquide céphalorachidien (LCR). Résultats précliniques: D'autre part, nous proposons un nouveau modèle de douleur à double atteinte chez le rongeur (i.e., induction initiale d'une douleur persistante [la 1ere atteinte] et activation subséquente des mécanismes descendants de modulation de la douleur à l'aide d'une douleur tonique [la 2e atteinte]). Ce paradigme expérimental nous permet ainsi d'évaluer l'efficacité des mécanismes descendants de modulation de la douleur chez les rongeurs en contexte de douleur chronique. Ainsi, nous mettons en évidence une diminution de la réponse comportementale à une douleur tonique (dans le test à la formaline), 28 jours après l'induction d'une douleur neuropathique (modèle de constriction chronique du nerf sciatique; CCI), lorsque comparés aux rats sham. Bien que cette diminution des comportements nociceptifs soit encore observable 168 jours après le début de la neuropathie, celle-ci semble tout de même s'amenuiser à travers le temps. Parallèlement, en l'absence de stimulation nociceptive tonique, une augmentation des concentrations en sérotonine et noradrénaline est observée au niveau central (i.e., dans le LCR) 12 jours après l'induction de la douleur neuropathique, avant de retourner ensuite à un niveau comparable à celui des rats sham au jour 28. Par ailleurs, la réponse comportementale observée au jour 28 est visible seulement dans un modèle de douleur neuropathique (CCI), et non lorsqu'une douleur inflammatoire est utilisée comme douleur persistante initiale. Conclusions: En contexte de douleur chronique, nos résultats chez l'humain confirment la présence de modifications dans l'efficacité des mécanismes descendants d’inhibition de la douleur, en plus de soutenir le concept émergent qui suggère que les différences dans l'efficacité de ceux-ci pourraient être associées à des différences individuelles dans certains processus périphériques (comme la relâche de catécholamines dans le sang), pouvant ultimement être impliquées dans la régulation cardiovasculaire. Par ailleurs, nos résultats chez le rongeur suggèrent que des changements dynamiques (spécifiques au type de douleur) dans l'efficacité des mécanismes descendants de modulation, ainsi que dans la fonctionnalité centrale des systèmes de neurotransmission monoaminergique, se produisent lors de la progression d'une douleur chronique. Dans son ensemble, cette thèse apporte de nouvelles informations au sujet des changements neurophysiologiques temporels au sein des mécanismes descendants de modulation de la douleur pouvant être impliqués dans le développement et la progression de la douleur chronique. / Abstract : Introduction: Hitherto, our understanding about the neurophysiological mechanisms responsible for the development of chronic pain is still relatively limited. It is suggested that modifications in the efficacy of endogenous pain inhibitory mechanisms could contribute to this phenomenon. Considering the importance of monoaminergic neurotransmission in descending pain modulation, either of inhibitory or facilitatory influence, we hypothesize that temporal persistence of pain can trigger modifications in the functionality of the two major systems (serotoninergic and noradrenergic) underlying these endogenous control mechanisms, thus participating in the development and progression of chronic pain states. General objective: Adopting a translational approach, we explored the association between the functionality (central & peripheral) of monoaminergic neurotransmission and the efficacy of descending inhibitory mechanisms during the development and progression of chronic pain. Clinical results: Our results replicate several observations emanating from the literature demonstrating a diminution in the efficacy of descending pain inhibitory mechanisms (using a conditioned pain modulation paradigm; CPM) in subjects with chronic musculoskeletal pain (CP subjects). In these CP subjects, we also highlight a reduction in basal plasma concentrations of noradrenaline and metanephrine, when compared with pain-free subjects (PF subjects). For all tested subjects (PF and CP subjects), a positive association is observed between CPM efficacy and basal plasma concentrations of noradrenaline and metanephrine. Therefore, basal plasma catecholamines concentrations could be used as molecular indicators of the latent CPM efficacy. Conversely, no difference in monoaminergic activity and no association with CPM efficacy are observed when looking at the molecular content of cerebrospinal fluid. Preclinical results: Here, we expose a new double-hit model of pain in rodents (i.e., initial induction of a persistent pain [the 1st hit] and subsequent activation of descending pain modulatory mechanisms with tonic pain [the 2nd hit]). This experimental paradigm allows us to evaluate the efficacy of decending pain modulation in rodents in the context of chronic pain. Interestingly, we detect a reduction in the behavioral response to tonic pain (in the formalin test), 28 days after the induction of neuropathic pain (chronic constriction injury model; CCI), when compared to sham rats. Even though this reduction in nociceptive behaviors is still present 168 days after neuropathy, the effect seems to wane down over time. Concomitantly, in absence of tonic nociceptive stimulation, an elevation in central concentrations (i.e., cerebrospinal fluid) in serotonin and noradrenaline is observed 12 days after the induction of neuropathic pain, before returning to sham levels on day 28. Moreover, the behavioral response described on day 28 is only observed in a neuropathic pain model (CCI), and absent when inflammatory pain is used as the initial pain. Conclusions: In the context of chronic pain, our results in humans confirm the advent of modifications in the efficacy of descending pain inhibitory mechanisms, while supporting the emerging concept suggesting that individual differences in these mechanisms may be associated with individual differences in peripheral processes (such as the release of catecholamines in plasma), that could ultimately be involved in cardiovascular control. Moreover, our results in rodents suggest that dynamic changes (specific to pain types) in the efficacy of descending pain modulation, as well as in the central functionality of monoaminergic neurotransmission, are present during the progression of chronic pain. Overall, this thesis provides novel information concerning temporal neurophysiological changes in descending pain modulatory mechanisms that may be involved in the development and progression of chronic pain states.

Hintergrund: Die bakterielle Meningitis hat eine Letalität von 10-20%. Das Hirnödem stellt bei ca. 14 % der Erkrankten eine prognosebestimmende Komplikation dar. Ein aktueller Forschungsansatz umfasst die Bedeutung der Aquaporine für die Entwicklung, Aufrechterhaltung und Resorption der verschiedenen Hirnödemformen, insbesondere des zytotoxischen und des vasogenen Hirnödems. In dieser Arbeit wird untersucht, ob Aquaporin 1 und Aquaporin 4 im Liquor von Patienten mit bakterieller und viraler Meningitis, im Vergleich zu einer gesunden Kontrollgruppe, nachweisbar sind. Zudem sollte geklärt werden, ob sich hieraus eine differenzialdiagnostische Einordnung ergibt und sich Rückschlüsse auf das Ausmaß eines Hirnödems und das Outcome schließen lassen. Methode: Aquaporin 1 und 4 wurde im Liquor und im Serum von Patienten mit bakterieller (nCSF = 35 , nSerum = 20) und viraler  (nCSF = 22) Meningitis sowie in einer Kontrollgruppe (nCSF = 27 , nSerum = 12) mittels eines (kommerziell erhältlichen) ELISAs bestimmt. Klinische Daten und Routinelaborparameter wurden verglichen und in Korrelation zu den Aquaporinkonzentrationen gesetzt. Ergänzend wurde bei einer Untergruppe der Patienten mit bakterieller Meningitis (n = 8) eine neuropsychologische Testung durchgeführt. Ergebnisse: Aquaporin 1 und 4 ließen sich in allen Gruppen nachweisen, ca. 40% der Aquaporin 4 Konzentrationen lagen unterhalb der Nachweisgrenze des ELISAs. Im Gruppenvergleich aller drei Gruppen unterschieden sich die Aquaporin 1-Konzentrationen (p = 0,0001) und die Aquaporin 4-Konzentrationen (p = 0,035) im Liquor signifikant voneinander. In der Gruppe der Patienten mit bakterieller Meningitis ließ sich eine negative Korrelation zwischen Aquaporin 1 und 4 im Liquor feststellen (r = - 0,519, p = 0,002). Aussagekräftige Korrelationen der klinischen Daten, der liquor- und laborchemischen Parameter sowie der neuropsychologischen Testergebnisse zu den Aquaporin 1- und Aquaporin 4-Konzentrationen fanden sich nicht.  Diskussion: In dieser Arbeit konnte erstmalig gezeigt werden, dass Aquaporin 1 und Aquaporin 4 im Liquor (und Serum) von Patienten mit einer bakteriellen und viralen Meningitis sowie in einer Kontrollgruppe nachweisbar sind. Für Aquaporin 1 und Aquaporin 4 im Liquor fanden sich signifikante Unterschiede im Vergleich aller Gruppen im Kruskal-Wallis-Test. Rückschlüsse bezüglich einer differenzial-diagnostischen Einordnung zur viralen Meningitis konnten nicht gezogen werden. Aussagen zur Schwere eines Hirnödems und zur Prognose können mit den vorliegenden Daten nicht getroffen werden. Der Ursprung der gemessenen Aquaporine bei Patienten mit Meningitis lässt sich in dieser Arbeit nicht abschließend klären und bedarf weiterer Grundlagenforschung.

Facial Artery Musculomucosal Flap in Skull Base Reconstruction Xie L. MD, Lavigne F. MD, Rahal A. MD, Moubayed SP MD, Ayad T. MD Introduction: Failure in skull base defects reconstruction can have serious consequences such as meningitis and pneumocephalus. The nasoseptal flap is usually the first choice but alternatives are necessary when this flap is not available. The facial artery musculomucosal (FAMM) flap has proven to be successful in head and neck reconstruction but it has never been reported in skull base reconstruction. Objective: To show that the FAMM flap can reach some key areas of the skull base and be considered as a new alternative in skull base defects reconstruction. Methods: We conducted a cadaveric study with harvest of modified FAMM flaps, endoscopic skull base dissection and maxillectomies in 13 specimens. Measures were taken for each harvested FAMM flap. Results: The approximate mean area for reconstruction from the combination of the distal FAMM and the extension flaps is 15.90 cm2. The flaps successfully covered the simulated defects of the frontal sinus, the ethmoid areas, the planum sphenoidale, and the sella turcica. Conclusion: The FAMM flap can be considered as a new alternative in the reconstruction of skull base defects. Modifications add extra length to the traditional FAMM flap and can contribute to a tighter seal of the defect as opposed to the FAMM flap alone. / Le lambeau musculomuqueux de la joue dans la reconstruction de la base du crâne Xie L. MD, Lavigne F. MD, Rahal A. MD, Moubayed SP MD, Ayad T. MD Introduction: Un échec dans la reconstruction de la base du crâne peut avoir des conséquences graves telles que la méningite ou la pneumocéphalie. Le premier choix de la reconstruction est le lambeau nasoseptal. Lorsque ce dernier n’est pas disponible, d’autres alternatives sont nécessaires. Le lambeau musculomuqueux de la joue (FAMM) a une place établie dans la reconstruction des déficits de la tête et du cou, mais il n’a pas jamais été décrit dans la reconstruction de la base du crâne. Objectif: Démontrer que le lambeau de FAMM peut atteindre des zones clés de la base du crâne et être considéré comme une nouvelle option de reconstruction de cette région. Méthode: Nous avons entrepris une étude cadavérique avec prélèvement de lambeaux de FAMM modifiés et une dissection endoscopique de la base du crâne sur 13 spécimens. Des mesures ont été prises pour chaque lambeau prélevé. Résultats: L’aire de reconstruction moyenne du lambeau de FAMM et des extensions est de 15.90 cm2. Les lambeaux couvrent totalement les déficits simulés du sinus frontal, des ethmoïdes, le toit du sphénoïde et la selle turcique. Conclusion: Le lambeau de FAMM peut être considéré comme une nouvelle alternative dans la reconstruction des déficits de la base du crâne. Les modifications apportent une longueur additionnelle et contribuent à une couverture plus étanche du déficit que le lambeau de FAMM seul.

No description available.

Cryptococcus neoformans (C. neoformans), um fungo que se encontra disseminado em várias partes do mundo, inclusive no Brasil, é o responsável pela criptococose infecção oportunista mais comum em pacientes com a síndrome da imunodeficiência adquirida (SIDA). O caráter sistêmico da criptococose pode levar esses pacientes a óbito. A finalidade de se obter um diagnóstico laboratorial rápido e acurado de C. neoformans, principalmente para o seguimento dos pacientes HIV nos levou a investigar \"seqüências iniciadoras\" (Si) A, B e C das regiões 18SrDNA, 5,8SrDNA e ITS do Cryptococcus spp. Pela Nested PCR com estas seqüências, sugerimos a melhor delas para o desenvolvimento de um diagnóstico molecular em relação aos métodos usuais. Para tal, foram avaliadas amostras de soro e líquor de 39 pacientes, que já haviam recebido tratamento clínico. Todos os casos foram selecionados em grupos, como segue:7 com criptococose (GIII), 14 HIV positivos (GIV), 18 HIV positivos associados com a criptococose (GV) em relação a 10 controles - indivíduos sadios (GI) e amostras de culturas referência (GII). Os resultados obtidos pela Nested PCR com as \"Sis\" A, B e C foram comparados àqueles obtidos pelos métodos de diagnóstico convencionais. As análises desse estudo mostraram que as \"Sis\" A, B e C detectam C. neoformans com especificidade variada, tanto no soro (SiA 91,66%, SiB-100%, SiC 75%), como no líquor (SiA 83,33%, SiB 100% e SiC 75%) mas não apresentaram falso positivo, quando esses resultados foram comparados aos obtidos das culturas heterólogas (GVI). A SiB, em líquor, apresentou sensibilidade, acurácia, valores preditivo positivo e negativo, e especificidade de 100% para a detecção de C. neoformans da mesma forma que no soro, porém neste o valor preditivo negativo foi 89%, acurácia 94% e a sensibilidade 88%. Em amostras de soro e líquor, os testes Tinta da China e Látex, mostraram resultados falso positivos para o GIV e falso negativos nos grupos GIII e GV. As análises comparativas entre as técnicas mostraram que a ordem de eficiência da sensibilidade para detecção de C. neoformans no soro foi SiB>SiA=Látex>SiC e no líquor foi SiB> SiA>tinta da China>Látex=SiC. No soro, a especificidade entre as técnicas foi SiB>SiA=Látex>SiC e no líquor foi SiB=tinta da China>Látex>SiA>SiC. De acordo com nossos dados, concluímos que, independente da doença associada (HIV) ou se o paciente for tratado, a SiB foi a melhor seqüência para a detecção de C. neoformans, tanto em amostras diretamente de soro, como de líquor para todos os grupos estudados. Tendo em vista os fatos, acreditamos que, a aplicação da técnica da Nested PCR com a \"SiB\", em amostras de líquor e soro, é um método viável e acurado para realizar o diagnóstico molecular do C. neoformans em pacientes HIV. O uso de amostras de soro, para o segmento dos pacientes com SIDA, durante o tratamento, pode ser a forma menos invasiva em relação ao líquor para a detecção do C. neoformans, com vantagens sobre os métodos utilizados / Cryptococcus neoformans (C. neoformans), a fungus that is widespread in many parts of the world, including Brazil, is responsible for cryptococcosis the most common opportunistic infection in patients with acquired immunodeficiency syndrome (AIDS). The systemic character of cryptococcosis may be fatal. In order to obtain a rapid and accurate laboratory diagnosis to follow - up of HIV-cryptococcosis patients led us to investigate the sensibility and especificity of three primers (A, B and C) of 18SrDNA, 5,8SrDNA and ITS regions of Cryptococcus spp. Using Nested PCR with those primers we suggest the best among them to be used as a method of molecular diagnosis in relation to the usual techniques. For this purpose, the serum and cerebrospinal fluid (CSF) of 39 patients, who had received medical treatment, were evaluated. All cases were separated in groups, as follows: 7 with cryptococcosis (group III), 14 HIV positive (group IV), 18 HIV positive associated with cryptococcosis (group V) were compared to, 10 healthy subjects (group I) controls, as well as to reference cultures (group II) samples. The results obtained by nested PCR with primers A and B and C were compared to those obtained by conventional diagnostic methods. The analyses of primers A, B and C detected C. neoformans both in serum (SiA 91,6%, SiB-100%, SiC 75%), and in CSF (SiA 83,3%, SiB 100% e SiC 75%). Besides, they were specific for the identification of C. neoformans and showed that there were no false positives when compared with heterologous cultures (group VI) samples. The primer B in CSF showed 100% sensitivity, 100% accuracy and 100% predictive values (positive and negative), and 100% specificity for the detection of C. neoformans, the same that occurs in serum, but in this case, with 88% in sensitivity, 89% predictive value negative and 94% accuracy. In serum and CSF samples the China Ink and the Latex tests showed false positive results for group IV and false negative for III and V groups. The comparative analysis among the techniques (Nested PCR, China Ink, Latex) indicated that the efficiency order of sensitivity for the detection of C. neoformans were PrB> PrA = Latex> PrC in serum and PrB > PrA > China Ink> Latex = PrC in CSF. For the serum and CSF specificities the same techniques were used with the following results: PrB>PrA=Latex>PrC and PrB=China Ink>Latex>PrA>PrC. According to our data we conclude that, whether the patients had been under treatment or not, the Nested PCR by PrB was the best way to detect C. neoformans both in serum and in CSF for all groups. The following up of AIDS patients, throughout the course of therapy was found to be feasible, accurate and less invasive to detect C. neoformans by using serum samples (directly)