Human-Soybean Allergies: Elucidation of the Seed Proteome and Comprehensive Protein-Protein Interaction Prediction

The soybean crop, Glycine max (L.) Merr., is consumed by humans, Homo sapiens, worldwide. While the respective bodies of literature and -omics data for each of these organisms are extensive, comparatively few studies investigate the molecular biological processes occurring between the two. We are interested in elucidating the network of protein-protein interactions (PPIs) involved in human-soybean allergies. To this end, we leverage state-of-the-art sequence-based PPI predictors amenable to predicting the enormous comprehensive interactome between human and soybean. A network-based analytical approach is proposed, leveraging similar interaction profiles to identify candidate allergens and proteins involved in the allergy response. Interestingly, the predicted interactome can be explored from two complementary perspectives: which soybean proteins are predicted to interact with specific human proteins and which human proteins are predicted to interact with specific soybean proteins. A total of eight proteins (six specific to the human proteome and two to the soy proteome) have been identified and supported by the literature to be involved in human health, specifically related to immunological and neurological pathways. This study, beyond generating the most comprehensive human-soybean interactome to date, elucidated a soybean seed interactome and identified several proteins putatively consequential to human health.

PIPE4: Fast PPI Predictor for Comprehensive Inter- and Cross-Species Interactomes

The need for larger-scale and increasingly complex protein-protein interaction (PPI) prediction tasks demands that state-of-the-art predictors be highly efficient and adapted to inter- and cross-species predictions. Furthermore, the ability to generate comprehensive interactomes has enabled the appraisal of each PPI in the context of all predictions leading to further improvements in classification performance in the face of extreme class imbalance using the Reciprocal Perspective (RP) framework. We here describe the PIPE4 algorithm. Adaptation of the PIPE3/MP-PIPE sequence preprocessing step led to upwards of 50x speedup and the new Similarity Weighted Score appropriately normalizes for window frequency when applied to any inter- and cross-species prediction schemas. Comprehensive interactomes for three prediction schemas are generated: (1) cross-species predictions, where Arabidopsis thaliana is used as a proxy to predict the comprehensive Glycine max interactome, (2) inter-species predictions between Homo sapiens-HIV1, and (3) a combined schema involving both cross- and inter-species predictions, where both Arabidopsis thaliana and Caenorhabditis elegans are used as proxy species to predict the interactome between Glycine max (the soybean legume) and Heterodera glycines (the soybean cyst nematode). Comparing PIPE4 with the state-of-the-art resulted in improved performance, indicative that it should be the method of choice for complex PPI prediction schemas.

Genetic Analysis of High Protein Content in 'AC Proteus' Related Soybean Populations Using SSR, SNP, DArT and DArTseq Markers

Key message: Several AC Proteus derived genomic regions (QTLs, SNPs) have been identified which may prove useful for further development of high yielding high protein cultivars and allele-specific marker developments. High seed protein content is a trait which is typically difficult to introgress into soybean without an accompanying reduction in seed yield. In a previous study, 'AC Proteus' was used as a high protein source and was found to produce populations that did not exhibit the typical association between high protein and low yield. Five high x low protein RIL populations and a high x high protein RIL population were evaluated by either quantitative trait locus (QTL) analysis or bulk segregant analyses (BSA) following phenotyping in the field. QTL analysis in one population using SSR, DArT and DArTseq markers found two QTLs for seed protein content on chromosomes 15 and 20. The BSA analyses suggested multiple genomic regions are involved with high protein content across the five populations, including the two previously mentioned QTLs. In an alternative approach to identify high protein genes, pedigree analysis identified SNPs for which the allele associated with high protein was retained in seven high protein descendants of AC Proteus on chromosomes 2, 17 and 18. Aside from the two identified QTLs (five genomic regions in total considering the two with highly elevated test statistic, but below the statistical threshold and the one with epistatic interactions) which were some distance from Meta-QTL regions and which were also supported by our BSA analysis within five populations. These high protein regions may prove useful for further development of high yielding high protein cultivars.

Anaesthesia for Implantation of the Jarvik 2000 Flowmaker® LVAD

The Jarvik 2000 Flowmaker® is an intraventricular continuous axial flow left ventricular assist device. We describe the anaesthetic management and considerations for five patients with end-stage heart failure who underwent implantation of the Jarvik 2000 Flowmaker® as a bridge to transplantation or as destination therapy.

Taeniasis and neurocysticercosis among Malaysians

Taeniasis, endemic in Southeast Asia, is caused by Taenia saginata (for beef) or Taenia solium and Taenia asiatica (for pork). T. solium also causes cysticercosis which can affect various organs. Taeniasis and cysticercosis cases are rarely reported in Malaysia. We report here two separate cases of beef taeniasis, and an interesting case of neurocysticercosis in a Malay Muslim. The taeniasis cases involved a Malaysian Chinese and a native Sabahan. Proglottids were recovered from them, and identification of the tapeworm done either from the microscopic examination of the egg or using PCR-based molecular diagnosis. Upon confirmation of taeniasis, both cases were given praziquantel and had been asymptomatic since. The neurocysticercosis case involving a Muslim who presented with seizure, was confirmed by histopathological examination of tissue sections taken from craniotomy excision of the brain lesion. He was given one month course of albendazole 400 mg bid and dexamethasone, and had been well and seizure free since. The two cases of taeniasis documented here had acquired the disease through eating raw or undercooked contaminated beef. For the neurocyticercosis case, it is suspected that he might have acquired the infection in one of his travels through human to human transmission via contaminated food or water consumption, given that Malaysia is not T. solium endemic area. Lastly praziquantel is an effective drug for beef taeniasis, while a combination of albendazole and dexamethasone work well for neurocysticercosis.

Effect of electroacupuncture on the cervicospinal P2X7 receptor/fractalkine/CX3CR1 signaling pathway in a rat neck-incision pain model

Increasing evidence supports that acupuncture intervention is an effective approach for intraoperative and postoperative pain. Neuron-microglia crosstalk, mediated by the purinergic P2X7 receptor (R)/fractalkine/CX3CR1 cascade in the spinal cord dorsal horn, plays a pivotal role in pain processing. However, its involvement in the analgesic effect of electroacupuncture (EA) remains unclear. In this study, a rat neck-incision pain model was established by making a longitudinal incision along the midline of the neck and subsequent repeated mechanical stimulation. EA stimulation was applied to bilateral LI18, LI4-PC6, or ST36-GB34. The thermal pain threshold, cervicospinal ATP concentration, expression levels of purinergic P2XR and P2YR subunits mRNAs, and fractalkine, CX3CR1 and p38 MAPK proteins, were detected separately. The neck incision induced strong thermal hyperalgesia and upregulation of spinal ATP within 48 h. No significant change was found in thermal hyperalgesia after a single session of EA intervention. However, a single session of EA dramatically enhanced the neck incision-induced upregulation of ATP and upregulated the expression of P2X7R, which was reversed by two sessions of EA. Two sessions of EA at bilateral LI18 or LI4-PC6 attenuated hyperalgesia significantly, accompanied with downregulation of P2X7R/fractalkine/ CX3CR1 signaling after three sessions of EA. EA stimulation of LI18 or LI4-PC6 alleviates thermal hyperalgesia in neck-incision pain rats, which may be associated with its effects in regulating the neck incision-induced increase of ATP and P2X7R and subsequently suppressing fractalkine/CX3CR1 signaling in the cervical spinal cord.

Giant Chondrosarcoma of Proximal Humerus in an Adult Female Patient: A Case Report

Chondrosarcoma is the third most common primary tumour of the bone, after myeloma and osteosarcoma. Most of the chondrosarcoma grow slowly and rarely metastasize, and they have an excellent prognosis after adequate surgery. However most of them are chemo or radio-resistant. We report a case of primary chondrosarcoma of proximal humerus in a 36-year-old female who presented with a six years history of left shoulder swelling and restricted range of motion. Trucut biopsy showed a well-differentiated chondrosarcoma. The patient underwent forequarter amputation of left upper limb and was started on chemotherapy following operation.

Trimethylation enhancement using diazomethane (TrEnDi): rapid on-column quaternization of peptide amino groups via reaction with diazomethane significantly enhances sensitivity in mass spectrometry analyses via a fixed, permanent positive charge

Defining cellular processes relies heavily on elucidating the temporal dynamics of proteins. To this end, mass spectrometry (MS) is an extremely valuable tool; different MS-based quantitative proteomics strategies have emerged to map protein dynamics over the course of stimuli. Herein, we disclose our novel MS-based quantitative proteomics strategy with unique analytical characteristics. By passing ethereal diazomethane over peptides on strong cation exchange resin within a microfluidic device, peptides react to contain fixed, permanent positive charges. Modified peptides display improved ionization characteristics and dissociate via tandem mass spectrometry (MS(2)) to form strong a2 fragment ion peaks. Process optimization and determination of reactive functional groups enabled a priori prediction of MS(2) fragmentation patterns for modified peptides. The strategy was tested on digested bovine serum albumin (BSA) and successfully quantified a peptide that was not observable prior to modification. Our method ionizes peptides regardless of proton affinity, thus decreasing ion suppression and permitting predictable multiple reaction monitoring (MRM)-based quantitation with improved sensitivity.

A global investigation of gene deletion strains that affect premature stop codon bypass in yeast, Saccharomyces cerevisiae

Protein biosynthesis is an orderly process that requires a balance between rate and accuracy. To produce a functional product, the fidelity of this process has to be maintained from start to finish. In order to systematically identify genes that affect stop codon bypass, three expression plasmids, pUKC817, pUKC818 and pUKC819, were integrated into the yeast non-essential loss-of-function gene array (5000 strains). These plasmids contain three different premature stop codons (UAA, UGA and UAG, respectively) within the LacZ expression cassette. A fourth plasmid, pUKC815 that carries the native LacZ gene was used as a control. Transformed strains were subjected to large-scale β-galactosidase lift assay analysis to evaluate production of β-galactosidase for each gene deletion strain. In this way 84 potential candidate genes that affect stop codon bypass were identified. Three candidate genes, OLA1, BSC2, and YNL040W, were further investigated, and were found to be important for cytoplasmic protein biosynthesis.

Comparison and critical appraisal of dengue clinical guidelines and their use in Asia and Latin America

The World Health Organization (WHO) dengue classification scheme for dengue fever (DF) and dengue haemorrhagic fever (DHF)/dengue shock syndrome (DSS) has been adopted as the standard for diagnosis, clinical management and reporting. In recent years, difficulties in applying the WHO case classification have been reported in several countries. A multicenter study was carried out in Asia and Latin America to analyze the variation and utility of dengue clinical guidelines (DCGs) taking as reference the WHO/PAHO guidelines (1994) and the WHO/SEARO guidelines (1998). A document analysis of 13 dengue guidelines was followed by a questionnaire and Focus Group discussions (FGDs) with 858 health care providers in seven countries. Differences in DCGs of the 13 countries were identified including the concept of warning signs, case classification, use of treatment algorithms and grading into levels of severity. The questionnaires and FGDs revealed (1) inaccessibility of DCGs, (2) lack of training, (3) insufficient number of staff to correctly apply the DCGs at the frontline and (4) the unavailability of diagnostic tests. The differences of the DCGs and the inconsistency in their application suggest a need to re-evaluate and standardise DCGs. This applies especially to case classification and case management.

High energy and average power femtosecond laser for driving mid-infrared optical parametric amplifiers

We have developed the first (to our knowledge) femtosecond Tm-fiber-laser-pumped Ho:YAG room-temperature chirped pulse amplifier system delivering scalable multimillijoule, multikilohertz pulses with a bandwidth exceeding 12 nm and average power of 15 W. The recompressed 530 fs pulses are suitable for broadband white light generation in transparent solids, which makes the developed source ideal for both pumping and seeding optical parametric amplifiers operating in the mid-IR spectral range.

Coherent polarization locking: an approach to mitigating optical damage in a pulsed Ho:YAG laser

Intracavity optical damage is mitigated in a pulsed Ho:YAG laser cavity using the coherent polarization locking (CPL) technique. By splitting the available pump power into two individual Ho:YAG laser rods, we passively coherently locked two orthogonal polarization lasers with 9.13 mJ output pulse energies and 14 ns pulsewidths, and operating at 800 Hz repetition rate. A conventional Ho:YAG laser cavity with the same pump and cavity configuration results in severe optical damage when operating at <2 kHz repetition rate, thus limiting the output pulse energies to <5 mJ. We also demonstrated, to the best of our knowledge, the first pulsed operation within the entire CPL Ho:YAG laser cavity by Q-switching in one of the polarization arms, producing nanosecond pulses with no sign of pulse instability.

Preserving a diffraction-limited beam in Ho:YAG laser using coherent polarization locking

We overcome several thermal issues present in Ho:YAG lasers by distributing the gain over a larger volume and achieve a diffraction-limited beam using coherent polarization locking. Increased single-pass absorption, suppression of output power saturation, and improvement in beam quality were shown using the coherent polarization locking technique as compared to a conventional Ho:YAG laser cavity with the same pump and cavity configuration. Ten watts of CW Ho:YAG laser power was generated with >96% coherent combining efficiency.

Recent advances in protein-protein interaction prediction: experimental and computational methods

INTRODUCTION

Proteins within the cell act as part of complex networks, which allow pathways and processes to function. Therefore, understanding how proteins interact is a significant area of current research.

AREAS COVERED

This review aims to present an overview of key experimental techniques (yeast two-hybrid, tandem affinity purification and protein microarrays) used to discover protein-protein interactions (PPIs), as well as to briefly discuss certain computational methods for predicting protein interactions based on gene localization, phylogenetic information, 3D structural modeling or primary protein sequence data. Due to the large-scale applicability of primary sequence-based methods, the authors have chosen to focus on this strategy for our review. There is an emphasis on a recent algorithm called Protein Interaction Prediction Engine (PIPE) that can predict global PPIs. The readers will discover recent advances both in the practical determination of protein interaction and the strategies that are available to attempt to anticipate interactions without the time and costs of experimental work.

EXPERT OPINION

Global PPI maps can help understand the biology of complex diseases and facilitate the identification of novel drug target sites. This study describes different techniques used for PPI prediction that we believe will significantly impact the development of the field in a new future. We expect to see a growing number of similar techniques capable of large-scale PPI predictions.

Unusual manifestation of cutaneous toxoplasmosis in a HIV-positive patient

We report a case of unusual cutaneous toxoplasmosis manifestation in a HIV-positive patient. He presented with hard and painful nodular lesions on the arms, hands and chest. Serology tests for anti-Toxoplasma antibody were negative. However, histopathologic examination of the lesion revealed foci of macrophages containing crescent-shaped organisms resembling the zoites of the protozoan parasite Toxoplasma gondii. Ultrastructure examination under electron microscopy and PCR confirmed the organism as T. gondii.

Effect of open-chest surgery in the lateral position on blood propofol concentration during target-controlled infusion of propofol

Our research hypothesis was that single lung ventilation during thoracic surgery in the lateral position increases the blood concentration of propofol during target-controlled infusion. Thirty adult patients in two tertiary referral hospitals undergoing open-chest surgery were studied. Anaesthesia was induced and maintained with propofol using a Diprifusor (Graseby 3500) computer-controlled pump set to deliver a blood concentration of 4 tg.ml(-1). Blood samples were taken with the patient positioned in (1) the supine position 20 minutes after induction (supine); (2) the lateral position just prior to one-lung ventilation (lateral); (3) the lateral position five minutes after commencing one-lung ventilation (OLV5) and (4) the lateral position 20 minutes after commencing one-lung ventilation (OLV20). Propofol concentrations were determined by high performance liquid chromatography. The target-controlled infusion target level was maintained at 4 microg.ml(-1) during the study period for all cases. The mean (SD) propofol blood concentration (microg.ml(-1)) at each stage was 5.5 (1.5) supine, 5.3 (1.1) lateral, 5.3 (1.2) OLV5 and 5.1 (1.2) OLV20. Repeated measures ANOVA showed an F value 1.9, lambda 5.5 and P value 0.15. Post hoc analysis did not identify a significant difference between the sample times. During target-controlled infusion of propofol, mean blood propofol concentrations did not change significantly from those obtained with the patient supine after up to 50 minutes in the lateral position during thoracic surgery, or 20 minutes after commencing one-lung ventilation.

Immunological profiles of immune restoration disease presenting as mycobacterial lymphadenitis and cryptococcal meningitis

OBJECTIVES

A proportion of HIV patients beginning antiretroviral therapy (ART) develop immune restoration disease (IRD). Immunological characteristics of IRD were investigated in a cohort of HIV patients beginning therapy in Kuala Lumpur, Malaysia.

METHODS

Peripheral blood mononuclear cells were collected at weeks 0, 6, 12, 24 and 48 of ART from five patients experiencing IRD [two with cryptococcal and three with Mycobacterium tuberculosis (Mtb) disease], eight non-IRD controls who had begun ART with CD4 T-cell counts of <100 cells/microL and 17 healthy controls. Leukocytes producing interferon-gamma (IFNgamma) were quantified by enzyme-linked immunospot assay after stimulation with purified protein derivative (PPD), early secretory antigenic target-6 (ESAT-6), Cryptococcus neoformans or Cytomegalovirus antigens. Plasma immunoglobulin (IgG) antibodies reactive with these antigens were assessed by enzyme-linked immunosorbent assay. Proportions of activated (HLA-DR(hi)) and regulatory (CD25 CD127(lo) and CTLA-4(+)) CD4 T-cells were quantified by flow cytometry.

RESULTS

Plasma HIV RNA declined and CD4 T-cell counts rose within 8-27 weeks on ART. Mtb IRD patients displayed elevated IFNgamma responses and/or plasma IgG to PPD, but none responded to ESAT-6. Cryptococcal IRD occurred in patients with low baseline CD4 T-cell counts and involved clear IFNgamma and antibody responses to cryptococcal antigen. Proportions of activated and regulatory CD4 T-cells declined on ART, but remained higher in patients than in healthy controls. At the time of IRD, proportions of activated CD4 T-cells and regulatory CD4 T-cells were generally elevated relative to other patients.

CONCLUSIONS

Cryptococcal and Mtb IRD generally coincide with peaks in the proportion of activated T-cells, pathogen-specific IFNgamma responses and reactive plasma IgG. IRD does not reflect a paucity of regulatory CD4 T-cells.

Effect of oil loading on microspheres produced by spray drying

Oil-loaded microspheres were produced by spray drying emulsions consisting of fish oil and modified starch suspensions with different oil loadings. The emulsion stability was assessed by oil droplet size analysis. Microspheres were characterized in terms of size, morphology, yield and microencapsulation efficiency. It was found that an increase in oil loading resulted in emulsions containing larger oil droplets. This corresponded with larger mean microsphere diameters and rounder microspheres. However, high oil loadings produced lower yields and affected microencapsulation efficiencies.

Accidental blood exposure: risk and prevention in interventional radiology

There is a growing concern about the transmission of bloodborne pathogens during medical procedures among health care workers and patients. Over the last three decades, radiological services have undergone many changes with the introduction of new modalities. One of these new disciplines is interventional radiology (IR) which deals with procedures such as arteriography, image-guided biopsies, intravascular catheter insertions, angioplasty and stent placements. Despite these developments, the potential for accidental blood exposure and exposure to other infectious material continues to exist. Therefore, it is important for all radiologists who perform invasive procedures to observe specific recommendations for infection control. In this review, we look at the different policies for protection and universal standards on infection control.

Neonate with vein of Galen malformation and heart failure: serial changes in plasma B-type natriuretic peptide following endovascular embolization

We report a neonate with vein of Galen malformation (VGM) who developed congestive heart failure (CHF) early after birth. Serial changes in plasma B-type natriuretic peptide (BNP) following an endovascular embolization procedure for VGM were mirrored in his clinical CHF status. The plasma BNP level markedly increased to 1800 pg/ml (normal, <100 pg/ml) in accordance with the severity of CHF. It rapidly decreased to 356 pg/ml during the first week after endovascular embolization for VGM. In the following 3 weeks there was an unexpected upward trend in plasma BNP despite echocardiography revealing normal biventricular function. After additional evaluation and treatment for CHF, BNP decreased again and the patient's clinical status concurrently improved. The patient was discharged with a normal BNP level. Monitoring serial plasma BNP provides valuable information regarding the need for additional evaluation or treatment of newborns with CHF and may be used to document improvement.

Cushing's syndrome in a patient with a corticotropin-releasing hormone-producing pheochromocytoma

OBJECTIVE

To present the first case of Cushing's syndrome attributable solely to ectopic production of corticotropin-releasing hormone by a pheochromocytoma.

METHODS

We summarize the clinical features and results of laboratory investigations in a patient with symptoms characteristic of Cushing's syndrome.

RESULTS

Although Cushing's syndrome is usually caused by ectopic production of adrenocorticotropic hormone (ACTH), our current patient had clinical and biochemical evidence of hypercortisolism in conjunction with "normal" ACTH levels and nonsuppressible serum and urinary cortisol levels on low-dose and high-dose dexamethasone suppression testing. An abdominal computed tomographic scan revealed a 7.7-cm mass in the left adrenal gland. Light microscopic examination and immunohistochemical staining showed a pheochromocytoma with mild cortical hyperplasia. Immunostaining was positive for corticotropin-releasing hormone but negative for ACTH.

CONCLUSION

To our knowledge, this is the first case of Cushing's syndrome in a patient with pheochromocytoma caused only by ectopic secretion of corticotropin-releasing hormone without accompanying secretion of ACTH.

Lymphomas involving Waldeyer's ring: placement, paradigms, peculiarities, pitfalls, patterns and postulates

INTRODUCTION

This review revisits Waldeyer's ring lymphomas as classified by the World Health Organisation.

MATERIALS AND METHODS

Sources of data include international studies on Waldeyer's ring lymphomas as well as from personal observations gleaned from lymphoma statistics of Singapore General Hospital, Changi General Hospital, Tan Tock Seng Hospital and National University Hospital within the last decade or so.

RESULTS

Waldeyer's ring shares many of the histopathological trends of the rest of mucosa-associated lymphoid tissue (MALT), such as the high frequency of diffuse large B-cell lymphomas, and the relative rarity of follicular lymphomas in spite of its rich endowment with reactive lymphoid follicles. However, extranodal marginal zone lymphoma or "MALToma" may not be as frequently encountered as in other mucosal sites. Furthermore, the placement of Waldeyer's ring is unique in that stark comparisons with the lymphopathology of the immediately anterior oronasal cavities can be made, with intriguing peculiarities such as the abrupt reversal of the ratio of B-cell to T/NK-cell lymphoma frequency upon crossing the imaginary line that separates the 2 regions. The differential diagnosis with regionally common lymphoma mimics, in particular reactive parafollicular hyperplasia and nasopharyngeal undifferentiated (lymphoepithelial) carcinoma of Schmincke pattern, both often aetiologically related to Epstein-Barr viral infection, is also discussed.

CONCLUSIONS

Recognition of the peculiarities and patterns of Waldeyer's ring lymphomas is important for accurate pathologic assessment. Postulates that attempt to account for the patterns and peculiarities of Waldeyer's ring lymphopathology can be used to direct further research.

A case of severe leptospirosis with pancytopaenia

Pancytopaenia is a rare clinical presentation of severe leptospirosis. We would like to report a case of severe leptospirosis that progressed to pancytopaenia despite initial penicillin therapy. The patient needed a second course of antibiotic with doxycycline to improve his persistent symptoms and cytopaenia. Persistent pancytopaenia in severe leptospirosis and its management were reviewed.

Localized morphological brain differences between English-speaking Caucasians and Chinese-speaking Asians: new evidence of anatomical plasticity

Deformation field morphometry was applied to magnetic resonance images to detect differences in brain shape between English-speaking Caucasians and Chinese-speaking Asians. Anatomical differences between these two groups were limited to gyri in the frontal, temporal and parietal lobes, which are known (through functional imaging studies) to differentiate Chinese speakers from English speakers. We interpret these anatomical differences as evidence of neural plasticity shaped by the process of language acquisition during childhood. While anatomical plasticity due to manual skill acquisition (e.g. in musicians) has been established, to our knowledge this is the first report of a brain anatomical difference attributable to a learned cognitive strategy.

Seroepidemiology of toxoplasmosis among HIV-infected patients and healthy blood donors

A cross-sectional study was carried out in University of Malaya Medical Centre, Kuala Lumpur. Blood samples from 100 HIV-infected patients and 203 Healthy Blood Donors (HBD) were collected and anti-Toxoplasma antibodies were detected by using conventional ELISA. The seroprevalence of toxoplasmosis in HIV/AIDS and Healthy Blood Donors were found to be 21% and 28.1% respectively. There was no significant association between the seroprevalence of toxoplasmosis and various possible risk factors i.e. contact with cat, consumption of undercooked meat and history of blood transfusion in both groups. No significant differences between Toxoplasma seroprevalence in HIV/AIDS and Healthy Blood Donors in association with presence of single or multiple risk factors were found. The mean CD4 count among HIV/AIDS patients in this study was 202.23 cell/cumm. There was no significant association between CD4 count and seropositivity for Toxoplasma antibodies in HIV/AIDS patients.

Anaesthetic considerations for lung volume reduction surgery--a case report

INTRODUCTION

This case describes some of the unique problems faced by the thoracic anaesthesiologists during anaesthesia for lung volume reduction surgery.

CLINICAL PICTURE

The usual pulmonary function requirements for lobectomy are normally not met in these patients with severe emphysema.

TREATMENT

Maintenance of the functional residual capacity of the lung and normocapnia during anaesthesia are not as important. Instead problems due to barotrauma and dynamic hyperinflation from positive pressure ventilation are.

OUTCOME

Modification of ventilation strategy and providing an anaesthetic tailored towards early extubation is the cornerstone of the anaesthetic plan.

CONCLUSION

A good understanding of the respiratory physiology in patients with severe emphysema is essential.

Meningioma presenting as a parapharyngeal tumor: report of a case with fine needle aspiration cytology

BACKGROUND

Meningiomas rarely extend out of their intracranial confines through skull foramina to present as cervical tumors, where they would be accessible to fine needle aspiration (FNA) and thereby create difficulties in cytodiagnosis by mimicking other, more commonly aspirated head and neck tumors.

CASE

A psammomatous meningioma arising intracranially and extending through the jugular foramen presented as a mass at the angle of the jaw clinically. On FNA cytology the diagnosis was suggested, but the cytomorphologic features overlapped with those of more commonly aspirated head and neck tumors, such as acinic cell carcinoma arising primarily in a salivary gland, metastatic papillary thyroid carcinoma and paraganglioma (glomus jugulare tumor). These possibilities had to be excluded through correlation with radiologic and intraoperative findings, which showed a dural-based tumor extending through the jugular foramen to assume a parapharyngeal location. Histology of the final excision specimen confirmed a psammomatous meningioma.

CONCLUSION

The possibility of meningioma should be considered in the cytologic differential diagnosis of parapharyngeal tumors, particularly since its cytomorphologic features may mimic those of some of the more commonly encountered and aspirated head and neck tumors.

Cerebral hemodynamic response in Chinese (first) and English (second) language processing revealed by event-related functional MRI

Comparative functional neuroimaging studies using the block design paradigm have previously demonstrated that there are no significant differences in the location of areas of cerebral activation when native Chinese speakers independently process single words or sentences in both the Chinese (first) and English (second) languages. While it has also been documented that significant domains of brain response include the inferior to middle left frontal lobe, the latency, amplitude and duration of the associated hemodynamic changes during isolated neural processing of Chinese and English languages still remain unknown. The aim of this study, therefore, was to examine the characteristics of the hemodynamic alterations in the above-mentioned regions with event-related functional MRI (ER-fMRI) when native Chinese speakers performed verb generation tasks in both the Chinese (first) and English (second) languages. Our results demonstrate the presence of a similar neural activity-induced hemodynamic response in the inferior to middle left frontal lobe during both tasks. Further, there were also no statistically significant differences among the variables that described the hemodynamic response curves. These findings strongly imply that the underlying neural mechanism for Chinese (first) and English (second) language processing may be similar in native Chinese speakers.

The neural system underlying Chinese logograph reading

Written Chinese as logographic script differs notably from alphabets such as English in visual form, orthography, phonology, and semantics. Thus, research on the Chinese language is important to advance our understanding of the universality and particularity of the organization of language systems in the brain. In this study, we examine the neural systems associated with logographic reading using functional magnetic resonance imaging. Two experimental tasks were devised, one based on semantic decision and the other on homophone decision. Compared to the fixation baseline, peak activations resulting from semantic as well as homophony decisions were localized in the left middle frontal gyrus (BA 9). Left inferior frontal cortex also mediated Chinese processing. In addition, more right hemisphere cortical regions (i.e., BAs 47/45, 7, 40/39, and the right visual system) were involved in reading Chinese relative to reading English. This is attributed to the square shape of the logograph which requires an elaborated analysis of the spatial information and locations of various strokes comprising the logographic character. We suggest that the left middle frontal area (BA 9) coordinates and integrates the intensive visuospatial analysis demanded by logographs' square configuration and the semantic (or phonological) analysis required by the present experimental tasks. Our study has implicated brain regions common to both logographic and alphabetic languages as well as brain regions specialized in processing logographs.

2-octylcyanoacrylate-assisted microvascular anastomosis: comparison with a conventional suture technique in rat femoral arteries

Standard microvascular anastomosis using only sutures is a well-established and successful technique; however, it is time-consuming and may cause vessel narrowing, needle trauma, and tissue reaction. The authors' hypothesis was that 2-octylcyanoacrylate could simplify microvascular anastomosis and reduce wall trauma and reaction. End-to-end anastomoses of the femoral arteries were performed in 20 adult rats. Each animal served as its own control. The time taken for each anastomosis (from first stitch to release of clamps) was noted, and the patency assessed. At day 7, the anastomoses were reassessed for patency, and the vessels evaluated histologically. 2-octylcyanoacrylate reduced the need to insert more sutures. Anastomotic time in the study group was statistically significantly shorter (p < 0.001), and the patency rate was 90 percent, compared to 85 percent with the standard suture technique. There was also less intense inflammatory reaction, with fewer foreign-body granulomata. This is the first report on the use of 2-octylcyanocrylate, currently approved for cutaneous use, for vessel anastomosis. Further work on the biomechanics and long-term histologic effects will be carried out. 2-octylcyanoacrylate has the potential for simplifying and improving the patency rates of arterial microanastomosis.

An fMRI study with written Chinese

Event-related functional magnetic resonance imaging (ER-fMRI) was used to investigate how the human brain processes phonology and transforms a word's visual form (orthography) into phonological form during reading in logographic Chinese, a writing system that differs markedly from alphabetic languages. We found that reading aloud of irregular words produced larger MR signal intensity changes over extensive regions involving left infero-middle frontal cortex, left motor cortex, right infero-frontal gyri, bilateral anterior superior temporal areas, and anterior cingulate cortex. Right superior parietal lobule, the cuneus in bilateral visual cortex, and thalamus participated in the processing of irregular, but not regular, words. These findings were discussed in comparison to neuroimaging findings from alphabetic languages, as well as in relation to models of reading.

The role of phonological codes in integrating information across saccadic eye movements in Chinese character identification

Prior research has generally assumed either that phonological codes do not contribute to Chinese character identification or that they do so only through a look-up process at the character level. In 3 experiments, a homophone seen parafoveally aided the identification of a target character that was fixated following an eye movement to the preview location. Moreover, high-frequency phonetically regular characters were named faster than high-frequency, phonetically irregular characters. Thus, both lexical and sublexical phonological codes of Chinese characters are involved early in the process of character identification. Orthographic information from the preview was also used in character identification, as orthographically similar previews facilitated target identification as well. The evidence for the extraction of semantic information from parafoveal previews was mixed, as synonym previews facilitated in Experiment 2 but not in Experiment 1.

Reading Chinese characters for meaning: the role of phonological information

Two experiments with the Stroop paradigm were conducted to investigate the role of phonological codes in access to the meaning of Chinese characters. Subjects named the ink color of viewed characters or color patches. Key items were color characters, their homophones with the same tone, homophones with different tones, and semantic associates. Apart from finding the usual Stroop interference effect, homophones produced significant interference in the incongruent condition, provided that they had the same tone as the color characters. The interference effect from homophones, however, was significantly smaller than that from color characters. Semantic associates generated an interference effect in the incongruent condition, an effect of the same magnitude as the effect from the same-tone homophones. Finally, in the congruent conditions, all the key items yielded facilitations compared to neutral controls, though the facilitation from color characters was larger than the facilitations from other types of characters. These findings suggest that phonological codes in Chinese are activated obligatorily and provide early sources of constraint in access to meaning.

Phonology matters: the phonological frequency effect in written Chinese

Does phonology play a role in silent reading? This issue was addressed in Chinese. Phonology effects are less expected in Chinese than in alphabetical languages like English because the basic units of written Chinese (the characters) map directly into units of meaning (morphemes). This linguistic property gave rise to the view that phonology could be bypassed altogether in Chinese. The present study, however, shows that this is not the case. We report two experiments that demonstrate pure phonological frequency effects in processing written Chinese. Characters with a high phonological frequency were processed faster than characters with a low phonological frequency, despite the fact that the characters were matched on orthographic (printed) frequency. The present research points to a universal phonological principle according to which phonological information is routinely activated as a part of word identification. The research further suggests that part of the classic word-frequency effect may be phonological.

Brain activation in the processing of Chinese characters and words: a functional MRI study

Functional magnetic resonance imaging was used to identify the neural correlates of Chinese character and word reading. The Chinese stimuli were presented visually, one at a time. Subjects covertly generated a word that was semantically related to each stimulus. Three sorts of Chinese items were used: single characters having precise meanings, single characters having vague meanings, and two-character Chinese words. The results indicated that reading Chinese is characterized by extensive activity of the neural systems, with strong left lateralization of frontal (BAs 9 and 47) and temporal (BA 37) cortices and right lateralization of visual systems (BAs 17-19), parietal lobe (BA 3), and cerebellum. The location of peak activation in the left frontal regions coincided nearly completely both for vague- and precise-meaning characters as well as for two-character words, without dissociation in laterality patterns. In addition, left frontal activations were modulated by the ease of semantic retrieval. The present results constitute a challenge to the deeply ingrained belief that activations in reading single characters are right lateralized, whereas activations in reading two-character words are left lateralized.

The role of phonological codes in integrating information across saccadic eye movements in Chinese character identification

Prior research has generally assumed either that phonological codes do not contribute to Chinese character identification or that they do so only through a look-up process at the character level. In 3 experiments, a homophone seen parafoveally aided the identification of a target character that was fixated following an eye movement to the preview location. Moreover, high-frequency phonetically regular characters were named faster than high-frequency, phonetically irregular characters. Thus, both lexical and sublexical phonological codes of Chinese characters are involved early in the process of character identification. Orthographic information from the preview was also used in character identification, as orthographically similar previews facilitated target identification as well. The evidence for the extraction of semantic information from parafoveal previews was mixed, as synonym previews facilitated in Experiment 2 but not in Experiment 1.

Rosai-Dorfman disease of the breast: a mimic of breast malignancy

Rosai-Dorfman disease (RDD) or sinus histiocytosis with massive lymphadenopathy (SHML) is primarily a nodal-based, idiopathic, benign proliferative disorder of histiocytes with 43% of these cases also involving extranodal sites. The breast is an unusual site of occurrence of RDD. We report two cases of this exceptional event. The first represents an intramammary nodal Rosai-Dorfman disease, while the second is an extranodal disease with sole involvement of the breast. In both, the possibility of malignancy was raised. Histological examination of the two breast lesions revealed sheets of characteristic large histiocytes displaying emperipolesis, a microscopic hallmark of this disease. Immunohistochemical and ultrastructural studies were also performed; the former showed cytoplasmic staining of histiocytes for S-100 protein, while histiocytes that engulfed lymphocytes and plasma cells were identified on electron microscopy.

The Internal Medicine Center--an integrated solution for information on internal medicine on the World Wide Web

The World Wide Web (WWW) has grown from being a resource center for a select group of scientists to a large database of information that is available to both professionals and public. The amount of medical information on the Web has been increasing exponentially and thus, it has become increasingly difficult for anyone to be able to search for a specific quantum of information among this mass. Even in mid 1996, it was noted that the amount of information on internal medicine was growing rapidly. Hence, on 21 March 1997, the Internal Medicine Center (IMC) was created and launched. The IMC is an unique concept and it represents the first time that medical data on the web has been organized into a form that intimately parallels clinical medicine. The rationale behind the creation of the IMC can be summarized in three words: information, speed and convenience. The interface used by this center reflects these goals because overuse of large image files are avoided, hence decreasing the access time and yet keeping the information in an easily comprehensible manner. In conclusion, the IMC serves as a useful tool for the layman as well as the expert because the comprehensive information that it offers can be accessed rapidly and conveniently.

Effects of perinatal diazepam exposure on the liver of rats

Diazepam is routinely used in obstetrics in the treatment of maternal eclampsia or as anesthetic induction during deliveries or cesarean sections. We investigated here the effects of perinatal diazepam treatment on the liver of Sprague Dawley rats. From 15th day of gestation to birth pregnant rats were treated daily in the first experimental group (DZ1) with 2.5 mg DZ/kg b.w., s.c., the second (DZ2) with 5 and the third (DZ3) with 10 mg DZ/kg b.w. After birth respective treatment was continued to the pups till 5th day postnatal. One half of pups from DZ2 and control was sacrificed at 12th day, the other were raised to 120th day and then sacrificed. After fixation in formaldehyde serial paraffin sections were processed with proliferating cell nuclear antigen (PCNA), autofluorescence of lipofuscin and Elastica v. Gieson staining. Livers from 12 day old rats showed increased levels of PCNA marked hepatocytes and lipofuscin containing cells. Livers from 120 day old animals exhibited increased levels of PCNA cells especially with weakly stained nuclei, the number of lipofuscin containing cells were decreased in DZ1 and DZ2 but reached in DZ3 the similar number as control. Statistical analysis showed that quantification of Kupffer cells lacked significance. To conclude livers of 12 day old animals demonstrated a stimulated DNA synthesis and an accumulation of nondegradable residues. Livers from 120 day old rats demonstrated an increase in number of potentially proliferating hepatocytes by increased levels of weakly stained PCNA nuclei. At lower dosage DZ seems to inhibit lipofuscinogenesis, at highest dosage DZ accumulates non-degradable residues. Elastica v. Gieson staining was not suitable to quantify Kupffer cells with certainty.

Erythropoietin production in rats with post-ischemic acute renal failure

To study the role of erythropoietin (Epo) in the pathogenesis of anemia in acute renal failure (ARF), organ Epo mRNA was measured by RNase protection assay in rats with ARF induced by a one hour-occlusion of the left renal artery. Hematocrit was significantly decreased two hours, 24 hours and one week after renal artery occlusion. A significant reduction in serum haptoglobin at two hours and an increase in serum LDH at 24 hours indicated that hemolysis was the likely cause of the initial fall in hematocrit. However, despite the reduced hematocrit, serum Epo concentrations were not significantly different from controls, suggesting that the anemia is maintained because of lack of an appropriate Epo response. Right renal Epo mRNA levels were not significantly different in all groups, but Epo mRNA levels in post-ischemic kidneys were 50 to 67% lower than in contralateral kidneys. However, Epo mRNA in the post-ischemic kidney was increased sixfold by acute hemorrhage, a rise comparable to the ninefold increase observed in contralateral kidneys. In ARF rats exposed to 7.5% O2 for four hours, right kidney Epo mRNA increased 200-fold over normoxic levels, to a value similar to sham-operated hypoxic controls. Epo mRNA in the post-ischemic kidney also increased 200-fold, to 50% of the level in the contralateral kidney. Hepatic Epo mRNA levels were elevated to comparable levels in both groups. In this ARF model, mild anemia is associated with relative Epo deficiency. In the post-ischemic kidney, a substantial capacity for Epo production is retained but the sensitivity of the Epo response to blood oxygen availability is significantly reduced.