Clinical predictors and angiographic features of acute coronary syndromes caused by systemic embolism

Introduction

Systemic embolism to coronary arteries is one of the mechanisms of acute myocardial infarction (AMI) of non-atherosclerotic cause. However, its clinical profile has not been properly established yet.

Purpose

To identify clinical predictors and angiographic characteristics of acute coronary syndromes caused by systemic embolism to a principal coronary artery (ACS-E), as well as to describe in-hospital mortality of these patients.

Methods

40 patients with ACS-E, admitted between 2003 and 2018 in a tertiary hospital. Epidemiological, clinical and angiographic characteristics of these cases were compared with those from 4989 patients, attended for acute coronary syndrome of atherosclerotic cause (ACS-A) in the same hospital during the same period.

Results

Patients with ACS-E were younger (28% vs 10% were <45 years old, p<0.001) and had a higher proportion of women (43% vs 22%, p 0.003), atrial fibrillation (40% vs 5%, p<0.001) and neoplasia (18% vs 7%, p 0.009). They had also undergone previous valvular surgery more frequently than patients with ACS-A (13% vs 0.5%, p<0.001) and a higher proportion of them were under treatment with warfarin (15% vs 3%, p<0.001). Variables identified as independent predictors of ACS-E in the multivariate analysis are shown in the table. Regarding clinical presentation, ST elevation AMI was more frequent in ACS-E cases (83% vs 67%, p 0.04). Patients with ACS-E did not present any significative stenosis in other vessels apart from the culprit one (number of other vessels with at least 1 severe stenosis was 0 in the ACS-E group vs 1.33 + 1 in the ACS-A arm, p<0.001). PCI was attempted in 75% of the patients with ACS-E, resulting successful in 80% of the cases. On the other hand, 100% of SCA-A underwent PCI, with a success proportion of 99% (p<0.001). In-hospital mortality in ACS-E group was 15% and 4% in the control group (p<0.001).

Conclusions

ACS-E and ACS-A have different clinical and angiographic features. Atrial fibrillation, chronic warfarin treatment, previous valvular surgery, presence of any neoplasia and female sex are independent predictors for ACS-E.

Funding Acknowledgement

Type of funding source: None

Chemical signals act as the main reproductive barrier between sister and mimetic Heliconius butterflies

Colour pattern is the main trait that drives mate recognition between Heliconius species that are phylogenetically close. However, when this cue is compromised such as in cases of mimetic, sympatric and closely related species, alternative mating signals must evolve to ensure reproductive isolation and species integrity. The closely related species Heliconius melpomene malleti and H. timareta florencia occur in the same geographical region, and despite being co-mimics, they display strong reproductive isolation. In order to test which cues differ between species, and potentially contribute to reproductive isolation, we quantified differences in the wing phenotype and the male chemical profile. As expected, the wing colour pattern was indistinguishable between the two species, while the chemical profile of the androconial and genital males' extracts showed marked differences. We then conducted behavioural experiments to study the importance of these signals in mate recognition by females. In agreement with our previous results, we found that chemical blends and not wing colour pattern drive the preference of females for conspecific males. Also, experiments with hybrid males and females suggested an important genetic component for both chemical production and preference. Altogether, these results suggest that chemicals are the major reproductive barrier opposing gene flow between these two sister and co-mimic species.

Prospects for PLD Inhibition in Cancer and Thrombotic Disease

Functions for phospholipase D1 and D2 (PLD1 and PLD2), the canonical isoforms of the PLD superfamily in mammals, have been explored using cell biological and animal disease models for two decades. PLD1 and PLD2, which are activated as a consequence of extracellular signaling events and generate the second messenger signaling lipid phosphatidic acid (PA), have been reported to play roles in settings ranging from platelet activation to the response to cardiac ischemia, viral infection, neurodegenerative disease, and cancer. Of these, the most tractable as therapeutic targets may be thrombotic disease and cancer, as will be discussed here in the context of ongoing efforts to develop small molecule PLD inhibitors.

Correlation between imagenological and histological diagnosis of bone tumors. A retrospective study

INTRODUCTION

The objective of this study was to retrospectively compare imaging techniques with histopathological findings from bone biopsy.

MATERIAL AND METHODS

Imaging techniques such as X-Ray, CT scan and MRI where compared with the histopathological findings from bone biopsy, in a population of 64 patients with bone tumors, with 64.1% of males and an age range of 5 to 79 years.

RESULTS

Histologically, 39.1% were malignant bone tumors, while 60.9% were benign. The X-ray showed 90% of diagnostic accuracy, with sensitivity of 92.9%, specificity of 87.5%, positive predictive value of 86.7% and negative predictive value of 93.3%. CT scan presented 75.9% of diagnostic accuracy, with 84.6, 68.8, and 84.6% of sensitivity, specificity, positive predictive value and negative predictive value, respectively. The MRI documented a diagnostic accuracy of 95.1%, with 94.4% os sensitivity, 95.7% of specificity, 94.4% of positive predictive value and 95.7% for negative predictive value. This showed a great agreement between the histology findings and those within the X-Ray and MRI (K = 0.8 and 0.9, respectively), but doesnt depreciate the value of bone biopsy in diagnosis of bone tumors.

CONCLUSION

This data showed good correlation between imagenological and histopatologic techniques.

P973Intravascular lithotripsy for lesion preparation in calcified coronary lesions: a prospective, observational, two-center registry

Background

Intravascular coronary lithotripsy (IVL) is a novel alternative treatment for heavily calcified lesions. This study sought to determine the strategy success and safety of IVL on calcified lesions in an all-comers cohort of patients.

Methods

Patients with moderate and severely calcified coronary lesions were screened in two centers in Spain and Germany starting April 2018. Until February 2019, 61 patients with 67 lesions were eligible for IVL. Patients were assigned to the following groups: A) Primary IVL therapy for patients with circumferential calcified de-novo coronary lesions (n=32), B) Secondary IVL therapy for patients with moderate or severe calcified coronary lesions in which conventional non-compliant balloon dilatation failed (n=18) and C) Tertiary IVL therapy in patients with in-stent stenosis due to stent underexpansion after previous stenting (n=17). Primary endpoint was strategy success and safety outcome. Strategy success was defined as successful stent delivery and expansion with attainment of <20% in-stent residual stenosis of the target lesion. Safety outcome were procedural complication, defined as coronary dissection, slow or no-reflow phenomenon, new coronary thrombus formation during PCI, abrupt vessel closure and device failure (inability to place the balloon, malfunction, or burst) and in hospital MACE.

Results

61 patients with 67 calcified lesions were treated with IVL. Mean diameter of calcified stenosis on quantitative coronary angiography was 72.02±13.8% at baseline and decreased to 17.7±15.84% (p-value: <0.01) after IVL with an acute gain of 1.9±0.63 mm. Mean minimal lumen diameter was 1.0±0.5 mm at baseline and increased after IVL to 2.9±0.6 mm. The overall average of applied pulses was 63±22. The primary endpoint of strategy success was reached overall in 85.2% of patients. 4 type b dissections (3 in group A, 1 in group B) were observed without further sequelae. There were no in-hospital MACE. In one patient (1.6%) non-ischemia driven target lesion failure was observed in routine follow up coronary angiography and was in need for revascularization. According to the subgroups, strategy success in primary IVL treatment (group A) and secondary IVL treatment (group B) was reached in 81.3% and 83.3% of cases, respectively. In tertiary IVL therapy (group C), the primary study endpoint was reached in 64.7% of cases. Device delivery and IVL treatment of target lesion could be performed in all lesions without vessel complications. 7 IVL balloons ruptured during treatment without any sequelae. Rupture was observed in most cases after repositioning of the balloon within the calcified lesion.

Conclusions

IVL provides a valid strategy for lesion preparation in severely calcified coronary lesions, with high success rate, and low procedural complication and MACE rates. Longitudinal studies will confirm if these favourable initial results of IVL-supported PCI are followed by good long-term results.

Interleukin 33/ST2 Axis Components Are Associated to Desmoplasia, a Metastasis-Related Factor in Colorectal Cancer

In colorectal cancer (CRC), cancer-associated fibroblasts (CAFs) are the most abundant component from the tumor microenvironment (TM). CAFs facilitate tumor progression by inducing angiogenesis, immune suppression and invasion, thus altering the organization/composition of the extracellular matrix (i.e., desmoplasia) and/or activating epithelial-mesenchymal transition (EMT). Soluble factors from the TM can also contribute to cell invasion through secretion of cytokines and recently, IL-33/ST2 pathway has gained huge interest as a protumor alarmin, promoting progression to metastasis by inducing changes in TM. Hence, we analyzed IL-33 and ST2 content in tumor and healthy tissue lysates and plasma from CRC patients. Tissue localization and distribution of these molecules was evaluated by immunohistochemistry (using localization reference markers α-smooth muscle actin or α-SMA and E-cadherin), and clinical/histopathological information was obtained from CRC patients. In vitro experiments were conducted in primary cultures of CAFs and normal fibroblasts (NFs) isolated from tumor and healthy tissue taken from CRC patients. Additionally, migration and proliferation analysis were performed in HT29 and HCT116 cell lines. It was found that IL-33 content increases in left-sided CRC patients with lymphatic metastasis, with localization in tumor epithelia associated with abundant desmoplasia. Although ST2 content showed similarities between tumor and healthy tissue, a decreased immunoreactivity was observed in left-sided tumor stroma, associated to metastasis related factors (advanced stages, abundant desmoplasia, and presence of tumor budding). A principal component analysis (including stromal and epithelial IL-33/ST2 and α-SMA immunoreactivity with extent of desmoplasia) allowed us to distinguish clusters of low, intermediate and abundant desmoplasia, with potential to develop a diagnostic signature with benefits for further therapeutic targets. IL-33 transcript levels from CAFs directly correlated with CRC cell line migration induced by CAFs conditioned media, with rhIL-33 inducing a mesenchymal phenotype in HT29 cells. These results indicate a role of IL-33/ST2 in tumor microenvironment, specifically in the interaction between CAFs and epithelial tumor cells, thus contributing to invasion and metastasis in left-sided CRC, most likely by activating desmoplasia.

An ultra-high vacuum scanning tunneling microscope operating at sub-Kelvin temperatures and high magnetic fields for spin-resolved measurements

We present the construction and performance of an ultra-low-temperature scanning tunneling microscope (STM), working in ultra-high vacuum (UHV) conditions and in high magnetic fields up to 9 T. The cryogenic environment of the STM is generated by a single-shot ³He magnet cryostat in combination with a ⁴He dewar system. At a base temperature (300 mK), the cryostat has an operation time of approximately 80 h. The special design of the microscope allows the transfer of the STM head from the cryostat to a UHV chamber system, where samples and STM tips can be easily exchanged. The UHV chambers are equipped with specific surface science treatment tools for the functionalization of samples and tips, including high-temperature treatments and thin film deposition. This, in particular, enables spin-resolved tunneling measurements. We present test measurements using well-known samples and tips based on superconductors and metallic materials such as LiFeAs, Nb, Fe, and W. The measurements demonstrate the outstanding performance of the STM with high spatial and energy resolution as well as the spin-resolved capability.

What shapes the continuum of reproductive isolation? Lessons from Heliconius butterflies

The process by which species evolve can be illuminated by investigating barriers that limit gene flow between taxa. Recent radiations, such as Heliconius butterflies, offer the opportunity to compare isolation between pairs of taxa at different stages of ecological, geographical, and phylogenetic divergence. Here, we report a comparative analysis of existing and novel data in order to quantify the strength and direction of isolating barriers within a well-studied clade of Heliconius Our results highlight that increased divergence is associated with the accumulation of stronger and more numerous barriers to gene flow. Wing pattern is both under natural selection for Müllerian mimicry and involved in mate choice, and therefore underlies several isolating barriers. However, pairs which share a similar wing pattern also display strong reproductive isolation mediated by traits other than wing pattern. This suggests that, while wing pattern is a key factor for early stages of divergence, it may become facultative at later stages of divergence. Additional factors including habitat partitioning, hybrid sterility, and chemically mediated mate choice are associated with complete speciation. Therefore, although most previous work has emphasized the role of wing pattern, our comparative results highlight that speciation is a multi-dimensional process, whose completion is stabilized by many factors.

Unsupported Micellar Palladium Nanoparticles for Biphasic Hydrogenation and Isomerization of Hydrophobic Allylic Alcohols in Water

This article presents the evaluation of water-soluble palladium nanoparticles with hydrophobic active sites that are ideal for the biphasic colloidal catalysis of water-insoluble organic substrates in aqueous solution. Palladium nanoparticles stabilized with ω-carboxylate-functionalized alkanethiolate are first synthesized using ω-carboxylate-S-alkylthiosulfate as their ligand precursor. The biphasic catalysis is carried out for the reaction of hydrophobic allylic alcohols without using any additional mixing solvent or surfactant, which results in the complete consumption of substrates under the atmospheric pressure of H₂ gas and at room temperature in less than 24 h. Systematic investigations on the influence of pH and substrate size are also performed to examine the utility of these thiolate-capped palladium nanoparticles as structurally stable and water-soluble micellar catalysts for the biphasic reaction.

'Squeezed' interparticle properties for plasmonic coupling and SERS characteristics of duplex DNA conjugated/linked gold nanoparticles of homo/hetero-sizes

The formation of interparticle duplex DNA conjugates with gold nanoparticles constitutes the basis for interparticle plasmonic coupling responsible for surface-enhanced Raman scattering signal amplification, but understanding of its correlation with interparticle spatial properties and particle sizes, especially in aqueous solutions, remains elusive. This report describes findings of an investigation of interparticle plasmonic coupling based on experimental measurements of localized surface plasmon resonance and surface enhanced Raman scattering characteristics for gold nanoparticles in aqueous solutions upon introduction of interparticle duplex DNA conjugates to define the interparticle spatial properties. Theoretical simulations of the interparticle optical properties and electric field enhancement based on a dimer model have also been performed to aid the understanding of the experimental results. The results have revealed a 'squeezed' interparticle spatial characteristic in which the duplex DNA-defined distance is close or shorter than A-form DNA conformation, which are discussed in terms of the interparticle interactions, providing fresh insight into the interparticle double-stranded DNA-defined interparticle spatial properties for the design of highly-sensitive nanoprobes in solutions for biomolecular detection.

STM Study of Au(111) Surface-Grafted Paramagnetic Macrocyclic Complexes [Ni2L(Hmba)](+) via Ambidentate Coligands

Molecular anchoring and electronic properties of macrocyclic complexes fixed on gold surfaces have been investigated mainly by using scanning tunnelling microscopy (STM) and complemented with X-ray photoelectron spectroscopy (XPS). Exchange-coupled macrocyclic complexes [Ni2L(Hmba)](+) were deposited via 4-mercaptobenzoate ligands on the surface of a Au(111) single crystal from a mM solution of the perchlorate salt [Ni2L(Hmba)]ClO4 in dichloromethane. The combined results from STM and XPS show the formation of large monolayers anchored via Au-S bonds with a height of about 1.5 nm. Two apparent granular structures are visible: one related to the dinickel molecular complexes (cationic structures) and a second one related to the counterions ClO4(-) which stabilize the monolayer. No type of short and long-range order is observed. STM tip-interaction with the monolayer reveals higher degradation after 8 h of measurement. Spectroscopy measurements suggest a gap of about 2.5 eV between HOMO and LUMO of the cationic structures and smaller gap in the areas related to the anionic structures.

Molecular cloning of Salmo salar Toll-like receptors (TLR1, TLR22, TLR5M and TLR5S) and expression analysis in SHK-1 cells during Piscirickettsia salmonis infection

In fish, the innate immune system is the primary response against infection. Toll-like receptors (TLRs) recognize pathogens through pathogen-associated molecular patterns (PAMPs), and some target molecules of TLRs are homologous between fish and mammals. Piscirickettsia salmonis is one of the main pathogens affecting the salmon industry in Chile. Better knowledge of mechanisms underlying its invasive capacity and recognition of target cells is crucial for vaccine development. Therefore, Salmo salar L. TLR1, TLR22, membrane TLR5M and soluble TLR5S sequences were cloned, and expression kinetics were analysed by RT-qPCR in salmon head kidney cells (SHK-1) infected with three different P. salmonis preparations: alive, formaldehyde treated, extract. Clearly, all analysed TLRs were expressed and transcription level changes were revealed at 2 hpi, 12 or 16 hpi and 24 hpi depending on P. salmonis infection scheme. Increased IL1-beta expression confirmed TLR pathway response. Furthermore, significant expression modulations of several members of the TLR pathway in this in vitro model suggest that P. salmonis extract rather than formaldehyde-inactivated bacteria might strengthen the salmon immune system.

Trend and seasonality in hospitalizations for pulmonary embolism: a time-series analysis

BACKGROUND

The existence of seasonal variability in patients with acute pulmonary embolism (PE) has been debated for years, with contradictory results. The aim of this study was to identify the trend and possible existence of a seasonal pattern in hospitalizations for PE in Spain.

METHODS

We analyzed the hospital discharge database of the Spanish National Health System from 2001 to 2010. Patients aged > 14 years diagnosed with PE were selected and a time series was constructed considering mean daily admissions for PE by month. The trend and seasonality factor of the series were determined using time-series analysis, and time-series modeling was used for analysis. Exponential smoothing models and the autoregressive integrated moving average test were used to generate a predictive model.

RESULTS

From 2001 to 2010, there were 162,032 diagnoses of PE (5.07 per 1000 hospitalizations). In 105,168 cases, PE was the reason for admission. The PE diagnosis rate ranged from 4.14 per 1000 in 2001 to 6.56 per 1000 in 2010; and hospital admissions due to PE ranged from 2.67 to 4.28 per 1000 hospital discharges. Time-series analysis showed a linear increase in the incidence and a significant seasonal pattern with 17% more admissions in February and 12% fewer in June-July with respect to the central tendency (difference from February to June, 29%).

CONCLUSIONS

The incidence of hospitalizations for PE showed a linear increase and a seasonal pattern, with the highest number of admissions in winter and the lowest number in summer.

EBV-associated post-transplant lymphoproliferative disorder after umbilical cord blood transplantation in adults with hematological diseases

We analyzed the incidence, clinicopathological features, risk factors and prognosis of patients with EBV-associated post-transplant lymphoproliferative disorder (EBV-PTLD) in 288 adults undergoing umbilical cord blood transplantation (UCBT) at a single institution. Twelve patients developed proven EBV-PTLD at a median time of 73 days (range, 36-812). Three-year cumulative incidence (CI) of EBV-PTLD was 4.3% (95% CI: 1.9-6.7). All patients presented with extranodal involvement. Most frequently affected sites were the liver, spleen, central nervous system (CNS), Waldeyer's ring and BM in 7, 6, 4, 3 and 3 patients, respectively. One patient had polymorphic and 11 had monomorphic EBV-PTLD (7 diffuse large B-cell lymphomas not otherwise specified, 4 plasmablastic lymphomas). We confirmed donor origin and EBV infection in all histological samples. EBV-PTLD was the cause of death in 11 patients at a median time of 23 days (range, 1-84). The 3-year CI of EBV-PTLD was 12.9% (95% CI: 3.2-22.5) and 2.6% (95% CI: 0.5-4.7) for patients receiving reduced-intensity conditioning (RIC) and myeloablative conditioning, respectively (P<0.0001). In conclusion, adults with EBV-PTLD after UCBT showed frequent visceral and CNS involvement. The prognosis was poor despite routine viral monitoring and early intervention. An increased risk of EBV-PTLD was noted among recipients of RIC regimens.

Release of gliotransmitters through astroglial connexin 43 hemichannels is necessary for fear memory consolidation in the basolateral amygdala

Recent in vitro evidence indicates that astrocytes can modulate synaptic plasticity by releasing neuroactive substances (gliotransmitters). However, whether gliotransmitter release from astrocytes is necessary for higher brain function in vivo, particularly for memory, as well as the contribution of connexin (Cx) hemichannels to gliotransmitter release, remain elusive. Here, we microinfused into the rat basolateral amygdala (BLA) TAT-Cx43L2, a peptide that selectively inhibits Cx43-hemichannel opening while maintaining synaptic transmission or interastrocyte gap junctional communication. In vivo blockade of Cx43 hemichannels during memory consolidation induced amnesia for auditory fear conditioning, as assessed 24 h after training, without affecting short-term memory, locomotion, or shock reactivity. The amnesic effect was transitory, specific for memory consolidation, and was confirmed after microinfusion of Gap27, another Cx43-hemichannel blocker. Learning capacity was recovered after coinfusion of TAT-Cx43L2 and a mixture of putative gliotransmitters (glutamate, glutamine, lactate, d-serine, glycine, and ATP). We propose that gliotransmitter release from astrocytes through Cx43 hemichannels is necessary for fear memory consolidation at the BLA. Thus, the present study is the first to demonstrate a physiological role for astroglial Cx43 hemichannels in brain function, making these channels a novel pharmacological target for the treatment of psychiatric disorders, including post-traumatic stress disorder.

Determination of phthalates in wine by headspace solid-phase microextraction followed by gas chromatography–mass spectrometry: Fibre comparison and selection

This paper describes the development of a headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) method for determining phthalates in wine. The HS-SPME conditions were thoroughly studied: first, the performance of six fibres at three temperature values and two sample volumes was surveyed by means of a 6 x 3 x 2 multi-factor categorical experimental design. From this study, three fibres - carbowax-divinylbenzene (CW-DVB), polyacrylate (PA) and polydimethylsiloxane-divinylbenzene (PDMS-DVB) - were selected. Then, temperature, sample volume and sodium chloride concentration were optimised using a central composite design and the overall desirability function for each fibre. The optimal values were 70 degrees C, a NaCl concentration of 2.6, 3.6 and 5.5M for PA, CW-DVB and PDMS-DVB fibres, respectively, and sample volumes of 4.0, 3.5 and 3.0 mL. Next, the performance characteristics of the three fibres were obtained and compared. PDMS-DVB fibre showed the best repeatability values followed by CW-DVB. PA fibre was not suitable for diethylhexylphthalate extraction and showed poor repeatability for the heavier phthalates, and was therefore discarded. Finally, the performance of CW-DVB and PDMS-DVB fibres was checked for red, white and rosé wines.

Timely diagnosis of MDR-TB under program conditions: is rapid drug susceptibility testing sufficient?

Timely diagnosis and effective, safe treatment are essential to reduce transmission and improve outcomes for patients with tuberculosis. Aside from laboratory methods, many programmatic factors influence the overall turnaround time (TAT) in diagnosing multidrug-resistant tuberculosis (MDR-TB). We measured each step in the overall TAT required for MDR-TB in two of five health districts of Lima, Peru. The total TAT, from initial sputum specimen to diagnosis and appropriate treatment, was 5 months, almost twice as long as the bacteriological procedures per se. Expensive investments in laboratory technology may yield low returns unless the programmatic aspects of the diagnostic process are streamlined at the same time.

Description of Endoscopic Ventricular Anatomy in Myelomeningocele

OBJECTIVE

The purpose of this work is to present our endoscopic neuroanatomical findings of a series of myelomeningocele and hydrocephalus patients, treated with endoscopic third ventricular cisternostomy (ETVC), in order to describe ventricular configuration abnormalities in this group of patients, in which this neurosurgical procedure has limited performance.

METHOD

We checked the videos of 10 endoscopic third ventricular cisternostomies of myelomeningocele patients taken during 24 months as from December 1998. A previous guideline is designed to record anatomic variables in the lateral ventricles, IIIrd ventricle, and basal cisterns. The topic is analyzed in view of the necropsy and imaging background data.

RESULTS

The ETVC of lateral ventricles showed: absence of septum (9/10); absence of anteroseptal vein (8/10); absence of choroid plexus and thalamostriate vein (0/10); absence of fornix (1/10): small foramen of Monro (4/10). The ETVC of the IIIrd ventricle showed: impossibility of recognizing any mammillary bodies (4/10); presence of septations (5/10); presence of atypical veins in the floor (6/10); translucent floor (5/10); floor umbilications (5/10); absence of infundibulum (4/10); arachnoid adherences (7/10); and visual contact of basilar artery (4/10).

CONCLUSION

There are categorical structural alterations in the ventricular system of myelomeningocele patients that are well correlated with previous necropsy and imaging reports. The ventricular system of dysraphic children presents severe anatomic alterations, which alter the reference points of the classical endoscopic third ventricular cisternostomy.

Effect of melatonin on hemolymph glucose and lactate levels in the fiddler crab Uca pugilator

Melatonin was injected into intact and eyestalk-ablated fiddler crabs (Uca pugilator), and its effects on hemolymph glucose and lactate levels were studied. In intact crabs, glucose and lactate levels cycled simultaneously, with peaks occurring during early and late photophase. Melatonin caused a shift in the glucose and lactate cycles, with only one peak occurring closer to mid-photophase. In eyestalk-ablated animals, the glucose rhythmicity was lost; lactate cycled, but levels were significantly lower than in intact animals. Melatonin caused a delayed hyperglycemia in eyestalk-ablated animals, with concurrent but much lower increases in lactate. Overall, melatonin demonstrated delayed hyperglycemic effects that do not appear to be mediated solely via eyestalk factors such as crustacean hyperglycemic hormone (CHH), though involvement of the eyestalks cannot be ruled out. An influence on extra-eyestalk CHH secretion is a potential mechanism of melatonin activity.

Sex-linked hybrid sterility in a butterfly

Recent studies, primarily in Drosophila, have greatly advanced our understanding of Haldane's rule, the tendency for hybrid sterility or inviability to affect primarily the heterogametic sex (Haldane 1922). Although dominance theory (Turelli and Orr 1995) has been proposed as a general explanation of Haldane's rule, this remains to be tested in female-heterogametic taxa, such as the Lepidoptera. Here we describe a novel example of Haldane's rule in Heliconius melpomene (Lepidoptera; Nymphalidae). Female F1 offspring are sterile when a male from French Guiana is crossed to a female from Panama, but fertile in the reciprocal cross. Male F1s are fertile in both directions. Similar female F1 sterility occurs in crosses between French Guiana and eastern Colombian populations. Backcrosses and linkage analysis show that sterility results from an interaction between gene(s) on the Z chromosome of the Guiana race with autosomal factors in the Panama genome. Large X (or Z) effects are commonly observed in Drosophila, but to our knowledge have not been previously demonstrated for hybrid sterility in Lepidoptera. Differences in the abundance of male versus female or Z-linked versus autosomal sterility factors cannot be ruled out in our crosses as causes of Haldane's rule. Nonetheless, the demonstration that recessive Z-linked loci cause hybrid sterility in a female heterogametic species supports the contention that dominance theory provides a general explanation of Haldane's rule (Turelli and Orr 2000).

Lead toxicity in cyanobacterial porphyrin metabolism

The effect of Pb2+ on growth, tetrapyrrole photosynthetic pigment content, total free porphyrin, and 5-aminolevulinate dehydratase (ALA-D) activity of a cyanobacterium, Microchaete tenera, and its ability to sequester Pb2+ from the culture medium were studied. Pb2+ was assayed by graphite furnace atomic absorption spectrophotometry. M. tenera growth and chlorophyll a content were not affected by 0.5, 1.0, and 6.0 ppm of Pb2+. These treatments doubled the protein content and increased the phycobiliprotein content by four times after 7 days. The ALA-D activity decreased in all concentrations by 63% at day 7 and by 34% at day 14. As a consequence of ALA-D inhibition, total free porphyrin also decreased by 64% at day 7 and by 40% at day 14. The highest biomass lead uptake (7454 +/- 565 micrograms Pb2+/g dry weight) was observed at day 3 with 6.0 ppm of Pb2+ in the culture medium. Uptake coefficient was highest (3723 +/- 279 micrograms Pb2+ g-1 dry weight/ppm of applied Pb2+) with 1.0 ppm after 3 days. The increase in protein and antenna pigments on day 7 was probably a response to stress conditions and could explain why the toxic metal did not affect growth. ALA-D inhibition and high lead biomass content confirm the importance of this enzyme as a biological indicator for stress.

[Mucoepidermoid carcinoma of the nasal vestibulum]

Mucoepidermoid carcinoma is a malignant epithelial tumor, with a mucosecretor component that is exceptional in the upper airways. It seems to be a kind of immunity in this area to the development of this tumors. In the review of the literature we only have found three cases in the nasal cavity. We present the case of a 18th years old woman with a tumor in the right nostril for two months. Several biopsy were required to achieve its histopathological diagnosis as a high malignant mucoepidermoid carcinoma. Radical surgery over the tumor and metastasis was performed but the case has a bad prognosis. The prognosis of the mucoepidermoid carcinoma depends on the histological grade, the early diagnosis and the surgical treatment which has to be so radical as possible to obtain free tumors limits.

Clinical experience with IVIg Rx in patients with prior failed IVF pregnancies: report of 30 consecutive patients

PROBLEM

This study reviews one practitioner's experience with intravenous immunoglobulin (IVIg) therapy in the in-vitro fertilization (IVF) cycles of 30 patients with previous IVF failures.

METHOD OF STUDY

Thirty patients had undergone 82 prior assisted reproductive technology (ART) cycles (mean 3.9 +/- 2 failed ART cycles, median 3.0, range 1-8) yielding one term birth, one loss at 22.5 weeks, and five chemical pregnancies. These patients underwent comprehensive clinical and laboratory evaluation, including immunologic workup, and were accepted for IVIg therapy in their next IVF cycle.

RESULTS

A total of 40 cycles were treated. Twenty-four (60%) of the IVIg-treated IVF cycles showed a positive human chorionic gonadotropin test. Comparing the IVIg cycles to the untreated ART cycles, there were no differences in the number of embryos transferred, fertilized embryos, or eggs. Eighty-six percent of the cases with confirmed implantation delivered; there was one chemical pregnancy, one 20-week spontaneous fetal death, and one trisomy. Five (24%) of the 21 pregnant patients delivered at 30-36 weeks. The remaining 13 delivered at term. Only three (11%) had no positive immune test.

CONCLUSION

In what may be a selected population of IVF patients (with high incidence of abnormal immune testing), early IVIg therapy may be associated with the improved success of IVF, and the high rate of live birth.

The management of desmoplastic neuroepithelial tumours in childhood

The authors report on the clinicopathological aspects of and management strategies for the group of rare, large hemispheric childhood tumours recently classified as desmoplastic infantile ganglioglioma (DIGG), desmoplastic astrocytoma of infancy (DACI) and pleomorphic xanthoastrocytoma (PXA). Between 1985 and 1997, ten children (4 with DACIs, 4 with DIGGs and 2 with PXAs) with a median age of 9.5 months were operated on. All these patients had complete surgical resections, with two having a preoperative biopsy. This led to an erroneous diagnosis in both cases of malignant grade 4 astrocytoma. As a result, one patient had preoperative chemotherapy with no effect. There was one perioperative death. Histology revealed heterogeneous tumours with malignant looking areas in 8 of the specimens. None of the patients has had any postoperative adjuvant treatment. All surviving patients are alive at follow-up (median 4.2 years). Despite their often malignant appearance, these tumours have an excellent prognosis, but they can present formidable surgical challenges when they occur in very young age patients. We believe that surgical excision can offer a cure and that adjuvant treatment is not necessary. Finally, biopsy is of little value and may even lead to an erroneous diagnosis and subsequent mismanagement.

[Myasthenia gravis. Otorhinolaryngological considerations]

Myasthenia gravis is a motor neuron disease caused by the presence of antibodies against acetylcholine receptors that interfere with proper functioning of the neuromuscular junction. Twenty percent of patients show bulbar involvement as the first indication of disease, with symptoms such as rhinolalia, dysphagia or phonasthenia. We report the cases of five patients for which our intervention was requested. We were involved in capacities ranging from the interpretation of the first symptom of disease to assessment of surgical possibilities for the treatment of chronic aspiration and severe respiratory symptoms in patients with major dysphagia. We review the scant bibliography published in the last five years.

[Forestier's disease. Ear, nose and throat manifestations]

Forestier's disease is a skeletal pathology that sometimes affects the head and neck as a consequence of hyperostotic involvement of the cervical spine. We report the case of a 73-year-old man who had progressive difficulty in swallowing solids. Gastrointestinal endoscopy revealed a bony mass in the hypopharynx. The case is described and the disease manifestations in head and neck are discussed.

The role of endoscopic third ventriculostomy in the management of shunt malfunction

OBJECTIVE

To evaluate the effectiveness of third ventriculostomy as an alternative to shunt revision in the management of shunt malfunction and infection in obstructive hydrocephalus.

METHODS

All of the clinical notes of 30 patients treated with third ventriculostomy for malfunctioning or infected shunts between January 1, 1974, and December 31, 1996, were retrospectively reviewed. Third ventriculostomy was performed under fluoroscopic control in the first seven patients and endoscopically in the remainder. A successful outcome was achieved if further shunt revision surgery was avoided. The median follow-up duration was 8.7 years

RESULTS

Twenty-three patients (76.7%) experienced successful outcomes, resulting in shunt independence. Of the seven failures, three were technical failures at the time of surgery and the remaining four were manifest within a median of 10 days, resulting in shunt revision. There have been no delayed failures.

CONCLUSION

Third ventriculostomy is a valuable alternative to shunt revision in patients affected by obstructive hydrocephalus presenting with shunt malfunction or infection. It should be considered in all suitable cases as the first-line treatment for obstructive hydrocephalus of all causes. Because all failures were manifest within a short time, it is likely that these successes will be durable.

Mental health screening by self-report questionnaire among community adolescents in southern Brazil

PURPOSE

To evaluate the frequency of symptoms of depression, suicidal ideation, suicide behavior, and hopelessness among adolescents in southern Brazil.

METHODS

The Self-Report Questionnaire (SRQ) was administered to a random sample of 126 community youngsters to screen for mental problems, the Montgomery-Asberg Depression Rating scale for signs and symptoms of depression, an adapted version of DIS (Diagnostic Interview Schedule) for suicidal ideation and behavior, and the Back's Hopelessness scale (adapted version). Social class, cognitive performance, age, and sex were also analyzed.

RESULTS

Levels of symptoms of depression, suicidal ideation and behavior, and hopelessness were higher among those who were SRQ positive (8%). Female youngsters presented higher SRQ scores and on the Montgomery-Asberg scale. Cognitive performance was similar among all groups. Differences were not found according to social classes. The 15-17 year-old individuals (middle stage) presented higher hopelessness than the other stages of adolescence.

CONCLUSIONS

The present findings suggest that screening for mental health conditions by self-report questionnaires may be of value of identify groups at major risk for violent, self-destructive behavior among community adolescents.

Severe cervical chyle fistula after radical neck dissection

The case of a chylous cervical fistula detected immediately after radical neck dissection is presented. The flow and metabolic derangements secondary to depletion of fluid, electrolytes, and protein required the ligation of the thoracic duct at the thoracic cavity. The various possible treatments of chylous fistula are reviewed.

Molecular cloning and characterization of the Bacillus subtilis spore photoproduct lyase (spl) gene, which is involved in repair of UV radiation-induced DNA damage during spore germination

Upon UV irradiation, Bacillus subtilis spore DNA accumulates the novel thymine dimer 5-thyminyl-5,6-dihydrothymine. Spores can repair this "spore photoproduct" (SP) upon germination either by the uvr-mediated general excision repair pathway or by the SP-specific spl pathway, which involves in situ monomerization of SP to two thymines by an enzyme named SP lyase. Mutants lacking both repair pathways produce spores that are extremely sensitive to UV. For cloning DNA that can repair a mutation in the spl pathway called spl-1, a library of EcoRI fragments of chromosomal DNA from B. subtilis 168 was constructed in integrative plasmid pJH101 and introduced by transformation into a mutant B. subtilis strain that carries both the uvrA42 and spl-1 mutations, and transformants whose spores exhibited UV resistance were selected by UV irradiation. With a combination of genetic and physical mapping techniques, the DNA responsible for the restoration of UV resistance was shown to be present on a 2.3-kb EcoRI-HindIII fragment that was mapped to a new locus in the metC-pyrD region of the B. subtilis chromosome immediately downstream from the pstI gene. The spl coding sequence was localized on the cloned fragment by analysis of in vitro-generated deletions and by nucleotide sequencing. The spl nucleotide sequence contains an open reading frame capable of encoding a 40-kDa polypeptide that shows regional amino acid sequence homology to DNA photolyases from a number of bacteria and fungi.

Chelation of endogenous membrane calcium inhibits gamma-aminobutyric acid uptake in synaptosomes

In a previous work, we have demonstrated that calcium chelators induce the release of gamma-aminobutyric acid (GABA) from synaptosomes in a Na+ -dependent manner and that this release is blocked by cations such as Mg2+, La3+, and ruthenium red. In the present study, we show that treatment of synaptosomes with 0.1 mM EGTA in the absence of both Ca2+ and Mg2+ inhibits the sodium-dependent high-affinity uptake of [3H]GABA by about 50%. This inhibition increased to about 65% with 1.5 mM EGTA, and it was completely prevented by an excess of Ca2+ or by 1.2 mM Mg2+. In contrast, when EDTA was used as a chelator, Mg2+ was unable to reverse the inhibition. The inhibitory effect of 0.1 mM EGTA was also prevented by 250 microM La3+ or by 20 microM ruthenium red. In the absence of chelators and the presence of Ca2+ and Mg2+, 50 microM and 200 microM La3+ inhibited GABA uptake by about 20 and 50%, respectively, whereas 20 microM ruthenium red produced a nonsignificant 25% inhibition and nifedipine was without effect. It is concluded that the membrane-surface negative charges, probably those of the sialic acid molecules that have been implicated in the functioning of the GABA carrier, must be neutralized by endogenous Ca2+ or by another cation in order to permit the adequate function of the transporter. The inhibition by La3+ in the absence of the chelators could be explained by a binding of this cation to the Na+ sites on the GABA carrier.

Lymphocyte percentage correlations for the Coulter S+IV

Previously performed correlation studies involving the Coulter S+II TM demonstrated a statistically significant bias for lymphocyte enumeration as compared with the results of lymphocyte enumeration by an automated differential counting system manufactured by Geometric Data, the Hematrak TM. New data developed utilizing the Coulter S+IV TM indicates that the previous bias has now been eliminated.

Distribution of ABO blood groups and other genetic markers in mothers of infants with congenital malformations

The distribution of ABO and Rh (antigen D) blood groups and of serum albumin, haptoglobin and transferrin variants, in a group of mothers of malformed newborns was investigated. In the first phase of the study, the results showed borderline statistical differences in the distribution of the transferrin types between the study group and a suitable control population. The second phase of the research, where only transferrin phenotypes were studied, showed the same trend as in the first one, but the results were not statistically significant. We conclude that probably there are no true distribution differences, but that it would be desirable to study this problem in a different ethnic group.