Leishmaniasis as an opportunistic infection in HIV-infected patients: determinants of relapse and mortality in a collaborative study of 228 episodes in a Mediterreanean region

The clinical presentation of visceral leishmaniasis shares similarities with other geographically specific infectious diseases associated with AIDS in terms of relapsing course and atypical presentation. However, visceral leishmaniasis has not, until now, been included in the AIDS case definition. The aim of this study was to describe the clinical features and determinants for relapse and case-fatality of visceral leishmaniasis in HIV-infected patients from a Spanish Mediterranean area. A chart review was conducted in 16 hospitals in the autonomous communities of Valencia and Murcia (Spain). From 1988 to 2001, a total of 228 episodes of visceral leishmaniasis were diagnosed in 155 HIV-infected patients by the detection of amastigotes in bone marrow aspirates or in other tissue samples. Most patients had advanced HIV disease, with a median CD4+ lymphocyte cell count of 55 cells × 10⁹ l, and 56% of them had a previous AIDS-indicator disease. The median duration of follow-up was 8.4 months. HIV-infected patients with visceral leishmaniasis presented with fever (76%), hepatomegaly (77%), splenomegaly (78%), and varying degrees of cytopenias. Leishmania was detected in atypical sites in 22 (14%) patients. A total of 37 (24%) patients had a relapse of visceral leishmaniasis. Female gender was a risk factor for relapse, whereas administration of secondary prophylaxis for visceral leishmaniasis and a completed therapy for visceral leishmaniasis were protective factors against relapse. A total of 86 (54%) patients died. Independent determinants for survival were CD4+ lymphocyte cell count, completed therapy for leishmania, and secondary prophylaxis for visceral leishmaniasis. The findings show that, in HIV-infected patients, visceral leishmaniasis occurs in late stages of HIV disease and often has a relapsing course. Secondary prophylaxis reduces the risk of relapse. Visceral leishmaniasis in the HIV-infected population should be included in the CDC clinical category C for the definition of AIDS in the same way that other geographically specific opportunistic infections are included.     

Effects of follicular fluid supplementation of in-vitro maturation medium on the fertilization and development of equine oocytes after in- vitro fertilization or intracytoplasmic sperm injection

The aim of this study was to compare the effect of the addition of follicular fluid (FF) collected from preovulatory follicles with that of oestrous mare serum (EMS) (acting as the control) to TCM-199 medium on the in-vitro maturation, fertilization and development of equine cumulus-enclosed oocytes. Oocytes (<30 mm in diameter) were obtained from the ovaries of slaughtered mares. After in-vitro maturation in the presence of the two supplements, their fertilization, cleavage and developmental potential were compared after conventional in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) using frozen-thawed spermatozoa. Follicular fluid did not increase the maturation of oocytes to metaphase II stage compared to control. After IVF, there was no difference in fertilization rates between FF- supplemented oocytes and controls (7/87, 8.4% of oocytes showing two pronuclei with FF versus 7/116, 6% with EMS; not significant). However, after ICSI, FF-supplemented oocytes showed significantly increased normal fertilization (32/85, 37.6% of two-pronuclear oocytes) and developmental potential (15/31, 48% cleavage) compared to the control oocytes (7/47, 14.9%, P < 0.01; and 2/48, 4%, P < 0.01, respectively). Overall, ICSI resulted in increased fertilization rates compared to IVF, regardless of the presence or absence of FF (39/132, 29.5% with ICSI versus 14/203, 6.9%). These results suggest that follicular fluid supplementation may improve the maturity of equine cumulus-enclosed oocytes sufficiently for the successful use of ICSI, but not sufficiently for normal sperm-egg interaction occurring during IVF.      

Identification of primary lysosomes in human megakaryocytes and platelets

The presence of lysosomal enzymes in human platelets is well documented; the identity of the "lysosome," however, has been the subject of some disagreement. In order to determine the time of appearance and subcellular localization of two lysosomal enzymes in megakaryocytes (MK) and platelets, we examined normal human bone marrow and blood by electron microscopy and cytochemistry. Acid phosphatase (AcPase) was present in the Golgi region in the youngest recognizable MK, as well as in those with a considerable degree of cytoplasmic maturation. Heavy reaction product was usually confined to one or two Golgi-associated cisternae and coated vesicles; other Golgi cisternae were sometimes lightly reactive. In mature MK, reaction product was limited to vesicles of variable size, but smaller than alpha-granules. Another lysosomal enzyme, arylsulfatase (AS), was localized in similar small vesicles in MK of all stages; it could not be demonstrated in the Golgi complex. Vesicles containing AS were also found in about 25% of platelet profiles, whereas vesicles containing AcPase were found in only about 15% of platelet profiles. The alpha-granules of all MK and platelets examined were negative for both enzymes. We conclude that the enzyme-containing vesicles in these cells constitute the lysosomes and that they are distinct from other platelet organelles. Since there was no evidence that they had participated in any digestive event, we believe that they are primary lysosomes, whose contents are secreted during platelet aggregation and the release reaction.     

Suppressive effect of phosphodiesterase type 4 inhibition on systemic inflammatory responses after cardiopulmonary bypass

Cardiopulmonary bypass (CPB) induces excessive production of endogenous proinflammatory mediators such as cytokines and elastase, which are responsible for the subsequent development of systemic inflammatory response syndrome (SIRS). In this study, we investigated the protective effect of rolipram against SIRS after CPB. Rats were divided into three groups (n = 5 in each): control (C), rolipram (R), and sham (S). Rats in groups C and R underwent CPB for 60 min followed by 60 min of observation, while those in group S were observed for 120 min without CPB. In group R, 40 μg/kg/min of rolipram was intravenously administered throughout the experiment. CD11b expression on neutrophils was analyzed using flow cytometry. Serum concentrations of tissue necrosis factor α (TNF-α), interleukin 1β (IL-1β), macrophage inflammatory protein 2 (MIP-2), and elastase were also determined. CD11b expression at the end of the experiment was unchanged from the initial value in group R, whereas that in group C increased to almost double, and that in group S also showed a slight increase (P < 0.01). Serum TNF-α levels in groups R and S were lower than those observed in group C (P < 0.05). Serum IL-1β and MIP-2 levels in groups C and R tended to be higher than those in group S, although the difference was not statistically significant. Regarding elastase, group R showed a significantly lower value than group C and a higher value than group S (P < 0.05). Phosphodiesterase type 4 inhibition seems to suppress CPB-induced SIRS through the regulation of proinflammatory mediators in this rat model.     

Linkage and physical mapping of X-linked lissencephaly/SBH (XLIS): a gene causing neuronal migration defects in human brain

While disorders of neuronal migration are associated with as much as 25% of recurrent childhood seizures, few of the genes required to establish neuronal position in cerebral cortex are known. Subcortical band heterotopia (SBH) and lissencephaly (LIS), two distinct neuronal migration disorders producing epilepsy and variable cognitive impairment, can be inherited alone or together in a single pedigree. Here we report a new genetic locus, XLIS, mapped by linkage analysis of five families and physical mapping of a balanced X;2 translocation in a girl with LIS. Linkage places the critical region in Xq21-q24, containing the breakpoint that maps to Xq22.3-q23 by high-resolution chromosome analysis. Markers used for somatic cell hybrid and fluorescence in situ hybridization analyses place the XLIS region within a 1 cM interval. These data suggest that SBH and X-linked lissencephaly are caused by mutation of a single gene, XLIS, that the milder SBH phenotype in females results from random X-inactivation (Lyonization), and that cloning of genes from the breakpoint region on X will yield XLIS.      

Specificity Improvement for Network Distributed Physiologic Alarms Based on a Simple Deterministic Reactive Intelligent Agent in the Critical Care Environment

Automated physiologic alarms are available in most commercial physiologic monitors. However, due to the variability of data coming from the physiologic sensors describing the state of patients, false positive alarms frequently occur. Each alarm requires review and documentation, which consumes clinicians’ time, may reduce patient safety through ‹alert fatigue’ and makes automated physician paging infeasible. To address these issues a computerized architecture based on simple reactive intelligent agent technology has been developed and implemented in a live critical care unit to facilitate the investigation of deterministic algorithms for the improvement of the sensitivity and specificity of physiologic alarms. The initial proposed algorithm uses a combination of median filters and production rules to make decisions about what alarms to generate. The alarms are used to classify the state of patients and alerts can be easily viewed and distributed using standard network, SQL database and Internet technologies. To evaluate the proposed algorithm, a 28 day study was conducted in the University of Michigan Medical Center’s 14 bed Cardiothoracic Intensive Care Unit. Alarms generated by patient monitors, the intelligent agent and alerts documented on patient flow sheets were compared. Significant improvements in the specificity of the physiologic alarms based on systolic and mean blood pressure was found on average to be 99% and 88% respectively. Even through significant improvements were noted based on this algorithm much work still needs to be done to ensure the sensitivity of alarms and methods to handle spurious sensor data due to patient or sensor movement and other influences. Blum JM, Kruger GH, Sanders KL, Gutierrez J, Rosenberg AL. Specificity improvement for network distributed physiologic alarms based on a simple deterministic reactive intelligent agent in the critical care environment.     

6Effect of a water load test on gastric myoelectrical activity and upper gastrointestinal symptoms in patients with nausea and vomiting of pregnancy

Nausea and vomiting of pregnancy (NVP) is a common syndrome in which symptoms predominate in the first trimester of pregnancy. Symptoms range from mild to severe and afflict up to 80% of pregnant women. The underlying mechanisms of NVP remain poorly understood. Provocative gastric function testing has not been performed in these patients. Aims: The aim of this study were to determine the effects of the water load test (WLT) on gastric myoelectrical activity, nausea, and other upper gastrointestinal symptoms in pregnant women. Method: 46 women with NVP were studied prospectively. Gastric myoelectrical activity was recorded throughout the study by electrogastrography (EGG). A 15 min baseline period was followed by a WLT during which patients ingested water until full over a 5 min period. After the WLT, an additional 30 min of EGG was recorded. EGG responses were categorized into four groups: normal (2.5–3.7 cpm), bradygastria (1.0–2.5 cpm), tachygastria (3.7–10.0 cpm), and mixed gastric dysrhythmia (tachygastria and bradygastria). Nausea, bloating, stomach fullness, and abdominal discomfort were recorded before, and 10, 20, and 30 minutes after the WLT on 100 mm visual analogue scales. Results: In response to the WLT, 14% of the women exhibited normal EGG responses, while significantly more (86%) exhibited gastric dysrhythmias (p < 0.01). Of the dysrhythmic EGG responses, 57% were tachygastria, 11% were bradygastria, and 18% were mixed gastric dysrhythmia. Patients with tachygastria ingested less water (338 ml) than patients with normal (371 ml), bradygastria (415 ml), or mixed gastric dysrhythmia (394 ml) patterns, but the differences were not statistically significant. 46% of the women reported nausea at baseline; significantly more women (72%) reported nausea after the WLT (p < 0.05). At 20 min after the WLT, a significant, direct relationship was observed between nausea severity and tachygastria (p < 0.05). The other upper gastrointestinal symptoms were not significantly increased by the WLT. Conclusions: (1) 86% of the pregnant women in this sample developed gastric dysrhythmias in response to the WLT. (2) Tachygastria was the most common dysrhythmia, and increased tachygastria was correlated with increased nausea. Gastric dysrhythmias are evoked by the WLT in women with NVP, suggesting these dysrhythmias have a pathophysiological role in the mechanism of NVP, and are a target for future therapies.     

Teaching paediatric epilepsy to medical students: A randomised crossover trial

Aim: Research has shown computerised tutorial to be as effective as face‐to‐face teaching in promoting knowledge acquisition. Subsequently, the clinician must synthesise and interpret data (clinical reasoning). This study extends previous research and compares the effectiveness of interactive lecture and computerised tutorial in promoting observational skills and clinical reasoning in the evaluation of paroxysmal events. Methods: The modalities were compared through a randomised crossover trial teaching epilepsy to third and fourth year medical students. The content matter (history and video clip) and format were identical for each topic (Topic 1: altered awareness, Topic 2: movement and posturing) in both modalities (interactive lecture and computerised tutorial). Structured worksheets promoted and evaluated skills of observation and clinical reasoning. Responses in both domains were compared with gold standard qualitative scores. Participants rated modality preference and perceptions of teaching. Results: One‐hundred and fifty‐seven medical students participated. Interactive lecture and computerised tutorial were both effective in promoting observational skills and clinical reasoning with no differences between modalities. Participants preferred the interactive lecture and rated it more enjoyable and effective. Twenty‐five participants randomised to the computerised tutorial for Topic 1, elected to withdraw participation. Both modalities promoted interest and willingness to further learn. Conclusion: This is the first randomised crossover trial evaluating the teaching of clinical reasoning in comparative medical education research. Interactive lecturing and computerised tutorial were both effective in teaching observational skills and clinical reasoning. Interactive lecture is the preferred method, and may influence initial engagement in learning.