Environmental physical factors produce mitotic aberration and multicellularity in the ovarian cancer cell line SKOV3

The spread of ovarian cancer (OC) to the coelomic cavity triggers the secretion and accumulation of ascitic fluid (AF). Although its biochemical composition has been well studied, less is known about the implications of physical factors such as the pH and the mechanical properties of the AF for the malignancy of tumor cells. In this work, we investigated the effect of pH and the mechanical properties of AF on cell proliferation and mitotic morphology. We employed biopsies from patients with OC and the SKOV3 cell line as an in vitro model of OC with HeLa cells as controls. Sections of each tumor were stained with HE, analyzed, and related to clinical data. AF from patients with OC exhibited an alkaline pH (ranging from 7.3 to 7.8). Compared to control conditions, the 3 AFs significantly enhanced the proliferation of SKOV3 and HeLa cells. These effects were more pronounced at a more alkaline pH. In addition, we found that AFs have different densities that correlated with a significant increase in multinucleated tumor cells and severe morphological defects in cells undergoing mitosis. In agreement with these data, we found that higher concentrations of soft agar provoked significantly higher numbers of multinucleated and morphologically abnormal SKOV3 cells with no effect on HeLa cells. We conclude that an alkaline pH and greater rigidity could enhance the metastatic potential of OC cells. We propose that these two physical factors could be parameters of clinical importance as predictors of malignancy.

Comparative effectiveness and cost-effectiveness of natalizumab and fingolimod in rapidly evolving severe relapsing-remitting multiple sclerosis in the United Kingdom

AIM

To evaluate the real-world comparative effectiveness and the cost-effectiveness, from a UK National Health Service perspective, of natalizumab versus fingolimod in patients with rapidly evolving severe relapsing-remitting multiple sclerosis (RES-RRMS).

METHODS

Real-world data from the MSBase Registry were obtained for patients with RES-RRMS who were previously either naive to disease-modifying therapies or had been treated with interferon-based therapies, glatiramer acetate, dimethyl fumarate, or teriflunomide (collectively known as BRACETD). Matched cohorts were selected by 3-way multinomial propensity score matching, and the annualized relapse rate (ARR) and 6-month-confirmed disability worsening (CDW6M) and improvement (CDI6M) were compared between treatment groups. Comparative effectiveness results were used in a cost-effectiveness model comparing natalizumab and fingolimod, using an established Markov structure over a lifetime horizon with health states based on the Expanded Disability Status Scale. Additional model data sources included the UK MS Survey 2015, published literature, and publicly available sources.

RESULTS

In the comparative effectiveness analysis, we found a significantly lower ARR for patients starting natalizumab compared with fingolimod (rate ratio [RR] = 0.65; 95% confidence interval [CI], 0.57-0.73) or BRACETD (RR = 0.46; 95% CI, 0.42-0.53). Similarly, CDI6M was higher for patients starting natalizumab compared with fingolimod (hazard ratio [HR] = 1.25; 95% CI, 1.01-1.55) and BRACETD (HR = 1.46; 95% CI, 1.16-1.85). In patients starting fingolimod, we found a lower ARR (RR = 0.72; 95% CI, 0.65-0.80) compared with starting BRACETD, but no difference in CDI6M (HR = 1.17; 95% CI, 0.91-1.50). Differences in CDW6M were not found between the treatment groups. In the base-case cost-effectiveness analysis, natalizumab dominated fingolimod (0.302 higher quality-adjusted life-years [QALYs] and £17,141 lower predicted lifetime costs). Similar cost-effectiveness results were observed across sensitivity analyses.

CONCLUSIONS

This MSBase Registry analysis suggests that natalizumab improves clinical outcomes when compared with fingolimod, which translates to higher QALYs and lower costs in UK patients with RES-RRMS.

Doppler images of intrapulmonary arteries within atelectasis and its impact on right ventricular afterload with transesophageal echocardiography

Video-assisted thoracoscopy (VATS) cardiac surgery requires one-lung ventilation (OLV) and transoesophageal ultrasound (TOE) monitoring. Colour and spectral Doppler make it possible to study the pattern of blood flow in the pulmonary vessels within the atelectatic lung. In this case report we describe how TOE can be used to detect blood flow within the atelectatic lung and to assess pulmonary vascular resistance (PVR) and right ventricular (RV) afterload. FINDINGS: Three anaesthetised, mechanically ventilated adults scheduled for cardiac surgery by VATS were scanned with TOE. After left OLV, the transducer was rotated away from the heart to obtain 2D colour Doppler images of blood flow within the consolidated lung parenchyma. We were able to identify the flow pattern of the intrapulmonary branches of the pulmonary artery. PVR was recorded using pulsed cardiac Doppler at baseline, after induction of general anaesthesia, 20 min after OLV and at the end of OLV, and after performing an alveolar recruitment manoeuvre (ARM) that led to complete resolution of the aforementioned consolidation. CONCLUSIONS: TOE is a semi-invasive imaging tool that can be used to diagnose and study PVR-induced atelectasis and to analyse the resulting pulmonary shunt and its possible effect on PVR.

Women are Taking the Hit: Examining the Unique Consequences of Cannabis Use Across the Female Lifespan

Cannabis use has risen dramatically in recent years due to global decriminalization and a resurgence in the interest of potential therapeutic benefits. While emerging research is shaping our understanding of the benefits and harms of cannabis, there remains a paucity of data specifically focused on how cannabis affects the female population. The female experience of cannabis use is unique, both in the societal context and because of the biological ramifications. This is increasingly important given the rise in cannabis potency, as well as the implications this has for the prevalence of Cannabis Use Disorder (CUD). Therefore, this scoping review aims to discuss the prevalence of cannabis use and CUD in women throughout their lifespan and provide a balanced prospective on the positive and negative consequences of cannabis use. In doing so, this review will highlight the necessity for continued research that goes beyond sex differences.

Rates of Post-Partum Psychosis in women with risk factors cared for by a specialist community perinatal mental health service in London

Introduction

Community Perinatal Mental Health Services (CPMHS) have been established in the UK, however, there is limited research around their real-world effectiveness. Post-Partum Psychosis (PPP), a severe episode of affective psychosis usually occurring soon after birth, has known risk factors. CPMHS offer assessment and interventions for women with risk factors for PPP, with a view to reducing the risk of its occurrence, as well as, where necessary, to proactively manage the illness to minimise the impact on the mother-infant dyad, as well as associated risks to self and/or others.

Objectives

To review the rate of PPP in women with established risk factors, who were referred and managed by our CPMHS between September 2019-September 2021. This rate will be compared with the known rates of PPP reported in the literature. Rates of non-psychotic relapse, acute hospitalisation, children social care supervision and mother-infant separation as a result of postnatal relapse will be (amongst others) secondary outcomes. Perinatal interventions offered to reduce the risk of PPP and contingency planning will also be reviewed.

Methods

This will be a retrospective case review study involving women referred and cared for by our CPMHS from October 2019 to October 2021, with known risk factors for PPP. Women identified as high risk for PPP receive consultant led-care in our service, therefore cases will be identified via the individual caseloads. Subsequently, electronic case notes will be reviewed to determine the primary and secondary outcomes, as well as the perinatal interventions that were offered.

Results

To be reported.

Conclusions

To be reported.

Disclosure

No significant relationships.

Linoleic and oleic acids enhance cell migration by altering the dynamics of microtubules and the remodeling of the actin cytoskeleton at the leading edge

Fatty acids (FA) have a multitude of biological actions on living cells. A target of their action is cell motility, a process of critical importance during cancer cell dissemination. Here, we studied the effect of unsaturated FA on ovarian cancer cell migration in vitro and its role in regulating cytoskeleton structures that are essential for cell motility. Scratch wound assays on human ovary cancer SKOV-3 cell monolayers revealed that low doses (16 μM) of linoleic acid (LA, 18:2 ω6) and oleic acid (OA; 18:1 ω9) promoted migration, while α-linolenic acid (ALA, 18:3 ω3), showed a migration rate similar to that of the control group. Single cell tracking demonstrated that LA and OA-treated cells migrated faster and were more orientated towards the wound closure than control. In vitro addition of those FA resulted in an increased number, length and protrusion speed of filopodia and also in a prominent and dynamic lamellipodia at the cell leading edge. Using time-lapse video-microscopy and FRAP we observed an increase in both the speed and frequency of actin waves associated with more mobile actin and augmented Rac1 activity. We also observed that FA induced microtubule-organizing center (MTOC)-orientation towards the cell front and affected the dynamics of microtubules (MT) in the direction of cell migration. We propose that environmental cues such as OA and LA present in ascitic fluid, should be taken into account as key factors for the regulation of cell migration.

FluoroType® MTB in pleural fluid for diagnosing tuberculosis

OBJECTIVES

This work aims to investigate the diagnostic accuracy of a nucleic acid amplification test (FluoroType MTB®) in pleural fluid (PF) and sputum to diagnose tuberculous pleural effusion (TPE). We also analyzed the increase in diagnostic accuracy of a second FluoroType MTB® test on a second thoracentesis sample when the first was negative.

METHODS

We conducted a prospective single-center study that included 207 patients with pleural effusion (31 tuberculous and 176 due to other causes). Of the 31 cases of TPE, 21 (68%) were confirmed histologically or microbiologically; the other cases were considered probable.

RESULTS

The operational characteristics of FluoroType MTB® in PF for identifying tuberculosis were a sensitivity of 13%, a specificity of 99%, a positive likelihood ratio of 11, and a negative likelihood ratio of 0.9. The diagnostic efficacy data for sputum samples were 21%, 91%, 2.4, and 0.9, respectively. PF and sputum cultures in solid and liquid media had greater sensitivity (36% and 31%, respectively). A second FluoroType MTB® test in PF was negative for 24 patients who had TPE and for whom the first FluoroType MTB® test was also negative. Only two (6.5%) patients with TPE had a confirmed diagnosis based exclusively on the positive results of the FluoroType MTB® in PF.

CONCLUSION

Due to its low sensitivity, the FluoroType MTB® test in PF has a limited role in diagnosing tuberculous pleurisy.

FluoroType® MTB in pleural fluid for diagnosing tuberculosis

OBJECTIVES

This work aims to investigate the diagnostic accuracy of a nucleic acid amplification test (FluoroType MTB®) in pleural fluid (PF) and sputum to diagnose tuberculous pleural effusion (TPE). We also analyzed the increase in diagnostic accuracy of a second FluoroType MTB® test on a second thoracentesis sample when the first was negative.

METHODS

We conducted a prospective single-center study that included 207 patients with pleural effusion (31 tuberculous and 176 due to other causes). Of the 31 cases of TPE, 21 (68%) were confirmed histologically or microbiologically; the other cases were considered probable.

RESULTS

The operational characteristics of FluoroType MTB® in PF for identifying tuberculosis were a sensitivity of 13%, a specificity of 99%, a positive likelihood ratio of 11, and a negative likelihood ratio of 0.9. The diagnostic efficacy data for sputum samples were 21%, 91%, 2.4, and 0.9, respectively. PF and sputum cultures in solid and liquid media had greater sensitivity (36% and 31%, respectively). A second FluoroType MTB® test in PF was negative for 24 patients who had TPE and for whom the first FluoroType MTB® test was also negative. Only two (6.5%) patients with TPE had a confirmed diagnosis based exclusively on the positive results of the FluoroType MTB® in PF.

CONCLUSION

Due to its low sensitivity, the FluoroType MTB® test in PF has a limited role in diagnosing tuberculous pleurisy.

Toxicological assessment of mesoporous silica particles in the nematode Caenorhabditis elegans

Here we report the toxicological evaluation of mesoporous silica particles (MSPs) in the nematode C. elegans. Specifically, we have investigated the effect of bare micro- (M0) and nano-sized (N0) MSPs, and their corresponding functionalized particles with a starch derivative (Glu-N) (M1 and N1, respectively) on C. elegans ageing parameters. The toxicity of MSPs, their impact on C. elegans lifespan, movement capacity, progeny and ability to survive upon exposure to acute oxidative stress were assessed. This study demonstrated that both size particles assayed (M0 and N0), labeled with rhodamine and monitored through fluorescence microscopy, are ingested by the nematode. Moreover, toxicity assays indicated that bare nano-sized particles (N0) have a negative impact on the C. elegans lifespan, reducing mobility and progeny production. By contrast, micro-sized particles (M0) proved innocuous for the nematodes. Furthermore, functionalization of nanoparticles with starch derivative reduced their toxicity in C. elegans. Thus, oral intake of N1 comparatively increased the mean lifespan and activity rates as well as resistance to oxidative stress. The overall findings presented here demonstrate the influence of MSP size and surface on their potential toxicity in vivo and indicate the silica-based mesoporous particles to be a potential support for encapsulation in oral delivery applications. Furthermore, the good correlation obtained between healthy aging variables and viability (mean lifespan) validates the use of C. elegans as a multicellular organism for nanotoxicology studies of MSPs.

Haemophilus Influenzae Type B Invasive Disease in a Pediatric Hospital of Argentina

Background

Since

The vaccination strategy is a three-dose primary series (at two,

Active surveillance is important to opportunely detect variations on these trends.

Methods

Cross-sectional study, including all hospitalized patients with Hib infection since 2012 to May 2017 at Hospital de Niños “Ricardo Gutiérrez” in Buenos Aires, Argentina.

Results

Twenty previously healthy children were admitted. Male/female ratio 1.8:1. Median age: 12 (range 45 days-114) months; 85% younger than 2 years and 35% younger than 6 months. Nine patients (45%) had complete vaccination schedule, with three or more doses of DTP-Hib-HBV vaccine. Hospitalization Hib infections by year in Table 1.

Clinical presentation: meningitis (14/20), pneumonia (6/20) and arthritis (5/20), osteomyelitis (1/20). All patients with meningitis, 25% of pneumonias and 50% of arthritis had positive blood cultures. Hib was isolated from blood in 17/20 cases, cerebrospinal fluid in 7/14, joint fluid in 3/5 and pleural fluid in 2/6. Median WBC: 12,400/mm3 (1,600–42,900) and median C-reactive protein level 111 mg/L (7–358). Median days of hospitalization was 13 (8–40). Nine patients required intensive care, four of them required mechanical ventilation. None patients died. Immunological studies ruled out immunodeficiency in 10 patients, although four continues under study.

Conclusion

(i) Burden of invasive Hib infections have increased over the last few years in our setting. (ii) Most of patient had adequate immunization schedule for age; (iii) Surveillance studies should be continued to confirm these preliminary results as well as to evaluate possible causes.

Disclosures

All authors: No reported disclosures.

Tuberculosis among migrants in Bishkek, the capital of the Kyrgyz Republic

Setting: Twenty-two first-line, two second-line and one tertiary health facility in Bishkek, the capital of Kyrgyzstan. Objectives: Among migrants, a marginalised population at risk for acquiring and transmitting tuberculosis (TB), we determined the proportion with TB among all registered TB cases. For those registered at primary-level facilities, we then reported on their demographic and clinical profiles and TB treatment outcomes. Design: This was a retrospective cohort analysis of 2012-2013 programme data. Results: Of 2153 TB patients registered in all health facilities, 969 (45%) were migrants, of whom 454 were registered in first-line facilities. Of these, 27% were cross-border migrants, 50% had infectious TB and 12% had drug-resistant TB. Treatment success was 74% for new cases and 44% for retreatment TB (the World Health Organization target is ⩾85%). Failure in new and retreatment TB patients was respectively 8% and 25%. Twenty-six individuals started on a first-line anti-tuberculosis regimen failed due to multidrug-resistant TB. Eight (25%) of 32 individuals on a retreatment TB regimen also failed. Loss to follow-up was 10% for new and 19% for retreatment TB. Conclusion: Migrants constituted almost half of all TB patients, drug resistance is prevalent and treatment outcomes unsatisfactory. Fostering inter-country collaboration and prioritising rapid TB diagnostics (Xpert^® MTB/RIF) and innovative ways forward for improving treatment outcomes is urgent.

Implementing Activities Developed by the Organ Transplantation Academic Society of the Hospital Dom Vicente Scherer: A Pilot Study

BACKGROUND

The number of academic societies has been growing significantly in Brazilian universities, offering an extra opportunity for the development of educational activities and research. Because organ donation and transplantation is an area still insufficiently approached during the graduation of health professionals, we evaluated how academic societies might be a valuable tool.

METHODS

Participants of the course promoted by the Organ Transplantation Academic Society of the Hospital Dom Vicente Scherer were evaluated through the use of a questionnaire and cognitive tests with 16 multiple-choice questions about topics approached during the course, before and after the lectures. Topics approached consisted of a general introduction about transplantation in Brazil, brain death, organ allocation and removal, post-transplant follow-up, and clinical cases.

RESULTS

Of the 45 participants, 30 answered the tests at both times. The subjects were students of medicine, nursing, and phonoaudiology; 93.3% were organ donors, 84.6% said their families knew about this decision, and 65% had relatives who were organ donors. The mean score of correct answers was 7.63 of 16 before the activities and 12.54 after activities, demonstrating a 64.4% improvement.

CONCLUSIONS

The improvement in performance suggests that academic societies are a useful resource for educational purposes and for students to get a deeper insight about organ donation and transplantation.

Two-year Experience of the "Organ Donation Week" of the Federal University of Health Sciences of Porto Alegre, Brazil

BACKGROUND

Today, Brazil is the second country of the world in number of transplants. Nonetheless, waiting lists are getting longer. This lack of organs occurs mostly because of people's reduced knowledge about the donation process. With the aim of changing this scenario, in 2013 and 2014, "Organ Donation Week" events were held at the Federal University of Health Sciences of Porto Alegre.

METHODS

During the 2 years, documentaries followed by a cycle of debates with experts in this area were exhibited. In 2013, a "flash-mob" took place, with the purpose of performing a "transplant waiting list" around the perimeter of Santa Casa's Hospital Complex. In 2014, a morning full of educational activities was planned for the pediatric patients from the Santo Antônio Children's Hospital and their relatives.

RESULTS

It is estimated that approximately 1774 people were directly reached by the projects. Among these people, we can include medical students, healthcare professionals, university staff, transplanted patients, and their families. We believe that education and consciousness are central points in the donation and transplant process. Through this project, we could inform people about it, solving their doubts and myths and stimulating this kind of conversation among the family circle, making the moment when the family must make the decision much easier.

CONCLUSIONS

Education and public awareness are essential for enhancing the number of organ donations. Therefore, events such as "Organ Donation Week" should be encouraged among medical schools.

Chirp- and random-based coded ultrasonic excitation for localized blood-brain barrier opening

Chirp- and random-based coded excitation methods have been proposed to reduce standing wave formation and improve focusing of transcranial ultrasound. However, no clear evidence has been shown to support the benefits of these ultrasonic excitation sequences in vivo. This study evaluates the chirp and periodic selection of random frequency (PSRF) coded-excitation methods for opening the blood-brain barrier (BBB) in mice. Three groups of mice (n  =  15) were injected with polydisperse microbubbles and sonicated in the caudate putamen using the chirp/PSRF coded (bandwidth: 1.5–1.9 MHz, peak negative pressure: 0.52 MPa, duration: 30 s) or standard ultrasound (frequency: 1.5 MHz, pressure: 0.52 MPa, burst duration: 20 ms, duration: 5 min) sequences. T1-weighted contrast-enhanced MRI scans were performed to quantitatively analyze focused ultrasound induced BBB opening. The mean opening volumes evaluated from the MRI were mm3, mm3and mm3 for the chirp, random and regular sonications, respectively. The mean cavitation levels were V.s, V.s and V.s for the chirp, random and regular sonications, respectively. The chirp and PSRF coded pulsing sequences improved the BBB opening localization by inducing lower cavitation levels and smaller opening volumes compared to results of the regular sonication technique. Larger bandwidths were associated with more focused targeting but were limited by the frequency response of the transducer, the skull attenuation and the microbubbles optimal frequency range. The coded methods could therefore facilitate highly localized drug delivery as well as benefit other transcranial ultrasound techniques that use higher pressure levels and higher precision to induce the necessary bioeffects in a brain region while avoiding damage to the surrounding healthy tissue.

Progression from severe sepsis in pregnancy to death: a UK population-based case-control analysis

Objective

To identify factors associated with progression from pregnancy‐associated severe sepsis to death in the UK.

Design

A population‐based case‐control analysis using data from the UK Obstetric Surveillance System (UKOSS) and the UK Confidential Enquiry into Maternal Death (CEMD).

Setting

All pregnancy care and death settings in UK hospitals.

Population

All non‐influenza sepsis‐related maternal deaths (January 2009 to December 2012) were included as cases (n = 43), and all women who survived severe non‐influenza sepsis in pregnancy (June 2011 to May 2012) were included as controls (n = 358).

Methods

Cases and controls were identified using the CEMD and UKOSS. Multivariable logistic regression was used to estimate adjusted odds ratios (aOR) with 95% confidence intervals.

Main outcome measures

Odds ratios for socio‐demographic, medical, obstetric and management factors in women who died from sepsis, compared with those who survived.

Results

Four factors were included in the final regression model. Women who died were more likely to have never received antibiotics [aOR = 22.7, 95% confidence interval (CI) 3.64–141.6], to have medical comorbidities (aOR = 2.53, 95%CI 1.23–5.23) and to be multiparous (aOR = 3.57, 95%CI 1.62–7.89). Anaemia (aOR = 13.5, 95%CI 3.17–57.6) and immunosuppression (aOR = 15.0, 95%CI 1.93–116.9) were the two most important factors driving the association between medical comorbidities and progression to death.

Conclusions

There must be continued vigilance for the risks of infection in pregnant women with medical comorbidities. Improved adherence to national guidelines, alongside prompt recognition and treatment with antibiotics, may reduce the burden from sepsis‐related maternal deaths.

Tweetable abstract

Medical comorbidities, multiparity and antibiotic delays increase the risk of death from maternal sepsis.

Urinary podocalyxin as a marker of preeclampsia in a Hispanic population

BACKGROUND

Preeclampsia is associated with significant materno-fetal morbidity and mortality. Podocyturia due to podocyte damage seems to be associated with the disease. The objective of this study was to evaluate the usefulness of urinary podocalyxin as a marker of preeclampsia in a Hispanic population.

METHODS

63 patients were studied. 25 patients had preeclampsia/eclampsia (PE-E). 38 patients had normal pregnancies and served as control group. 24 hour proteinuria, urine protein/creatinine (UPC), urinary podocalyxin and perinatal outcomes were measured. A Podocalyxin ELISA test was used to detect podocyturia.

RESULTS

Mean age (years), mean±SD was 30.5±5.4 in normal patients vs 30.6±5.8 in PE-E, p=0.98. Median gestational age (weeks) was, 38 (range 21-42) for normal pregnancies and 36 (range 24-40) for patients with PE-E, <0.001. Urine podocalyxin/creatinine on admission (ng/mg), median [IQR] in normal patients was 55.9 [29.4, 74.9] vs 109.7 [63.8, 234.1] in PE-E, p=0.001. After adjusting for admission proteinuria, urinary podocalyxin remained independently associated with preeclampsia: OR=1.0040 (95% CI 1.0003-1.0078), p=0.03. There was low to moderate correlation between UPC and urinary podocalyxin, Spearman's =0.31, p=0.01. In PE-E, post-partum urine podocalyxin was lower, median [IQR]: 69.7 [32.7, 184.8] p=0.19 vs admission. There was a trend towards more podocyturia and proteinuria in patients with eclampsia, comparing to those with preeclampsia. There was no association observed between podocyturia and neonatal mortality, IUGR or Apgar scores.

CONCLUSIONS

Significantly higher levels of urinary podocalyxin are seen in preeclampsia/eclampsia. They tend to normalize after delivery.

Polymer composites containing gated mesoporous materials for on-command controlled release

Polyamidic nanofibrous membranes containing gated silica mesoporous particles, acting as carriers, are described as novel hybrid composite materials for encapsulation and on-command delivery of garlic extracts. The carrier system consists of MCM-41 solids functionalized in the outer surface, with linear polyamines (solid P1) and with hydrolyzed starch (solid P2), both acting as molecular gates. Those particles were adsorbed on electospun nylon-6 nanofibrous membranes yielding to composite materials M1 and M2. FE-SEM analysis confirmed the presence of particles incorporated on the nylon nanofibers. The release of the entrapped molecules (garlic extract) from the P1, P2, M1, and M2 materials was evaluated using cyclic voltammetry measurements. Electrochemical studies showed that at acidic pH P1 and M1 were unable to release their entrapped cargo (closed gate), whereas at neutral pH both materials release their loading (open gate). Dealing with P2 and M2 materials, in the absence of pancreatin a negligible release is observed (closed gate), whereas in the presence of enzyme the load is freely to diffuse to the solution. These newly developed composite nanomaterials, provide a homogeneous easy-to-handle system with controlled delivery and bioactive-protective features, having potential applications on pharmacology, medical and engineering fields.

Expression and properties of hyperpolarization-activated current in rat dorsal root ganglion neurons with known sensory function

The hyperpolarization-activated current (I(h)) has been implicated in nociception/pain, but its expression levels in nociceptors remained unknown. We recorded I(h) magnitude and properties by voltage clamp from dorsal root ganglion (DRG) neurons in vivo, after classifying them as nociceptive or low-threshold-mechanoreceptors (LTMs) and as having C-, Aδ- or Aα/β-conduction velocities (CVs). For both nociceptors andLTMs, I(h) amplitude and I(h) density (at -100 mV) were significantly positively correlated with CV.Median I(h) magnitudes and I(h) density in neuronal subgroupswere respectively:muscle spindle afferents(MSAs):-4.6 nA,-33 pA pF(-1); cutaneous Aα/β LTMs: -2.2 nA, -20 pA pF(-1); Aβ-nociceptors: -2.6 nA, -21 pA pF(-1); both Aδ-LTMs and nociceptors: -1.3 nA, ∼-14 pA pF(-1); C-LTMs: -0.4 nA, -7.6 pA pF(-1); and C-nociceptors: -0.26 nA, -5 pApF(-1). I(h) activation slow time constants (slow τ values) were strongly correlated with fast τ values; both were shortest in MSAs. Most neurons had τ values consistent with HCN1-related I(h); others had τ values closer to HCN1+HCN2 channels, or HCN2 in the presence of cAMP. In contrast, median half-activation voltages (V(0.5)) of -80 to -86 mV for neuronal subgroups suggest contributions of HCN2 to I(h). τ values were unrelated to CV but were inversely correlated with I(h) and I(h) density for all non-MSA LTMs, and for Aδ-nociceptors. From activation curves ∼2-7% of I(h)would be activated at normal membrane potentials. The high I(h) may be important for excitability of A-nociceptors (responsible for sharp/pricking-type pain) and Aα/β-LTMs (tactile sensations and proprioception). Underlying HCN expression in these subgroups therefore needs to be determined. Altered high I(h) may be important for excitability of A-nociceptors (responsible for sharp/pricking-type pain) and Aα/β-LTMs (tactile sensations and proprioception). Underlying HCN expression in these subgroups therefore needs to be determined. Altered Ih expression and/or properties (e.g. in chronic/pathological pain states) may influence both nociceptor and LTM excitability.expression and/or properties (e.g. in chronic/pathological pain states) may influence both nociceptor and LTM excitability.

Immunostaining for the α3 isoform of the Na+/K+-ATPase is selective for functionally identified muscle spindle afferents in vivo

Muscle spindle afferent (MSA) neurons can show rapid and sustained firing. Immunostaining for the α3 isoform of the Na⁺/K⁺-ATPase (α3) in some large dorsal root ganglion (DRG) neurons and large intrafusal fibres suggested α3 expression in MSAs (Dobretsov et al. 2003), but not whether α3-immunoreactive DRG neuronal somata were exclusively MSAs. We found that neuronal somata with high α3 immunointensity were neurofilament-rich, suggesting they have A-fibres; we therefore focussed on A-fibre neurons to determine the sensory properties of α3-immunoreactive neurons. We examined α3 immunointensity in 78 dye-injected DRG neurons whose conduction velocities and hindlimb sensory receptive fields were determined in vivo. A dense perimeter or ring of staining in a subpopulation of neurons was clearly overlying the soma membrane and not within satellite cells. Neurons with clear α3 rings (n = 23) were all MSAs (types I and II); all MSAs had darkly stained α3 rings, that tended to be darker in MSA1 than MSA2 units. Of 52 non-MSA A-fibre neurons including nociceptive and cutaneous low-threshold mechanoreceptive (LTM) neurons, 50 had no discernable ring, while 2 (Aα/β cutaneous LTMs) had weakly stained rings. Three of three C-nociceptors had no rings. MSAs with strong ring immunostaining also showed the strongest cytoplasmic staining. These findings suggest that α3 ring staining is a selective marker for MSAs. The α3 isoform of the Na⁺/K⁺-ATPase has previously been shown to be activated by higher Na⁺ levels and to have greater affinity for ATP than the α1 isoform (in all DRG neurons). The high α3 levels in MSAs may enable the greater dynamic firing range in MSAs.

Functionalised polysiloxanes as injectable, in situ curable accommodating intraocular lenses

The aged eye's ability to change focus (accommodation) may be restored by replacing the hardened natural lens with a soft gel. Functionalised polysiloxane macromonomers, designed for application as an injectable, in situ curable accommodating intraocular lens (A-IOL), were prepared via a two-step synthesis. Prepolymers were synthesised via ring opening polymerisation (ROP) of octamethylcyclotetrasiloxane (D(4)) and 2,4,6,8-tetramethylcyclotetrasiloxane (D(4)(H)) in toluene using trifluoromethanesulfonic acid (TfOH) as catalyst. Hexaethyldisiloxane (HEDS) was used as the end group to control the molecular weight of the prepolymers, which were then converted to macromonomers by hydrosilylation of the SiH groups with allyl methacrylate (AM) to introduce polymerisable groups. The resulting macromonomers had an injectable consistency and thus, were able to be injected into and refill the empty lens capsular bag. The macromonomers also contained a low ratio of polymerisable groups so that they may be cured on demand, in situ, under irradiation of blue light, in the presence of a photo-initiator, to form a soft polysiloxane gel (an intraocular lens) in the eye. The pre-cure viscosity and post-cure modulus of the polysiloxanes, which are crucial factors for an injectable, in situ curable A-IOL application, were controlled by adjusting the end group and D(4)(H) concentrations, respectively, in the ROP. The macromonomers were fully cured within 5 min under light irradiation, as shown by the rapid change in modulus monitored by photo-rheology. Ex vivo primate lens stretching experiments on an Ex Vivo Accommodation Simulator (EVAS) showed that the polysiloxane gel refilled lenses achieved over 60% of the accommodation amplitude of the natural lens. An in vivo biocompatibility study in rabbits using the lens refilling (Phaco-Ersatz) procedure demonstrated that the soft gels had good biocompatibility with the ocular tissue. The polysiloxane macromonomers meet the targeted optical and mechanical properties of a young natural crystalline lens and show promise as candidate materials for use as injectable, in situ curable A-IOLs for lens refilling procedures.

Outcomes of colonization with MRSA and VRE among liver transplant candidates and recipients

Methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococcus (VRE) infections cause significant morbidity and mortality among liver transplant candidates and recipients. To assess rates of MRSA and VRE colonization, we obtained active surveillance cultures from 706 liver transplant candidates and recipients within 24 h of admission to an 11-bed liver transplant ICU from October 2000 to December 2005. Patients were followed prospectively to determine the cumulative risk of MRSA or VRE infection or death by colonization status. Outcomes were assessed by Kaplan-Meier survival analysis and Cox regression and multivariate logistic regression adjusting for covariates. The prevalence of newly detected MRSA nasal and VRE rectal colonization was 6.7% and 14.6%, respectively. Liver transplant candidates and recipients with MRSA colonization had an increased risk of MRSA infection (adjusted OR = 15.64, 95% CI 6.63-36.89) but not of death (adjusted OR = 1.00, 95% CI 0.43-2.30), whereas those with VRE colonization had an increased risk both of VRE infection (adjusted OR = 3.61, 95% CI 2.01-6.47) and of death (adjusted OR = 2.12, 95% CI 1.27-3.54) compared with noncolonized patients. Prevention and control strategies, including use of active surveillance cultures, should be implemented to reduce the rates of both MRSA and VRE colonization in this high-risk patient population.

Assessment of lipid and essential fatty acids requirements of black seabream (Spondyliosoma cantharus) by comparison of lipid composition in muscle and liver of wild and captive adult fish

The primary aim of the present study was to compare the contents of total lipid, lipid classes and their associated fatty acids in muscle and liver of wild and one-year captive black seabream (Spondyliosoma cantharus) adults, in order to elucidate the lipid and fatty acids requirements of this fish species of potential interest for aquaculture. The total lipid contents (TL) of muscle and liver of the captive fish were 2.5-fold greater than those of the wild fish. In consequence, contents of triacylglycerols were much higher in tissues of the captive fish. Distribution of fatty acids in total lipids and lipid classes of muscle and liver was also different between both groups of fish. For instance, percentages of 20:4n-6, 20:5n-6 and 22:6n-3 were considerably higher in the wild fish, whereas 18:1, 20:1, and 22:1n-9 as well as 18:2n-6 and 20:5n-3 were more abundant in the captive fish. These results suggest that the lipid composition of the commercial diet supplied to the captive black seabream differed greatly from that of the diet consumed by the fish in the wild, which hypothetically contains the desirable composition for the lipid nutrition of this fish species. Despite the good growth and survival achieved by the black seabream after one year in captivity, the significant accumulation of lipids and the imbalance of essential fatty acids in their muscle and livers, together with the absence of spawning, suggest that future research on the lipid requirements of this omnivorous species is necessary in order to establish whether the administration of currently available aquaculture formulated feeds is adequate for good black seabream performance and reproduction.

[Arterialization of the distal veins of the foot for limb salvage in arteritis. Techniques and results]

STUDY AIM

The aim of this retrospective study was to report the long term results with arterialisation of the veins of the foot as the final attempt to save an ischaemic limb when classical techniques have proved ineffective or impossible.

PATIENTS AND METHOD

From January 1974 to July 2000, 60 arterialisations of the distal veins of the foot were performed in 59 patients with arteritis, associated in 25 of them with diabetes mellitus. There were 41 men and 18 women, their mean age was 72 years (range from 49 to 95 years). There were 50 stage IV patients and 9 stage III patients. The arterialisation was performed by a reversed venous bypass between the femoral or popliteal artery and an internal vein of the foot, after destruction of the valvulas of the forefoot veins. The distal anastomosis was made termino lateral in order to provide tissular nutrition and to avoid blood congestion.

RESULTS

The result was considered good when a major amputation was avoided during one year at least, with a bypass permeability longer than one month. Among the 60 arterialisations, 36 were successful (60%), 7 in the short term (between one month and one year), 15 in the medium term (between one and five years), 14 in the long term (more than 5 years). Among the 15 medium-term good results, the mean time of bypass permeability was one year; three patients died, six were lost of follow-up, and six were still alive, four of them with a permeable bypass, at the time of the study. Among the 14 long term results, spontaneous bypass occlusion occurred after a 26-month mean time; despite this occlusion, the favourable result persisted till the death of the patient after a mean delay of 9 years (range from 5 to 15 years). The 24 other patients had a poor result followed by a major amputation. There were no deaths in relation with the reversed circulation.

CONCLUSION

These results suggest that the arterialisation of the distal veins of the foot may be considered a useful revascularization technique for limb salvage when all the classical methods have failed or are impossible.

Clinical, surgical, and histopathologic characteristics of corneal keloid

PURPOSE

To describe the cause, diagnosis, and management of a case of bilateral corneal keloid.

METHODS

We describe a 17-year-old white boy with enlarging nontraumatic bilateral corneal scars whose growth was exacerbated by a superficial keratectomy. The patient underwent a penetrating keratoplasty (PK) in his left eye. Light and electron microscopy of the corneal button were performed.

RESULTS

The histopathologic and ultrastructural features of the corneal button were haphazardly arranged collagen fascicles with activated fibroblasts but no inflammatory cells. The clinical outcome was excellent, although there has been continuous growth of the outer margin of the initial lesion not included in the PK. This growth has not affected vision. The unoperated right corneal lesion progressively enlarged during these years.

CONCLUSION

A corneal keloid, although unusual, should be suspected in cases of enlarging white glistening avascular corneal scars regardless of a traumatic antecedent. Light and electron microscopy confirmed the diagnosis. Management is by PK when the visual axis is involved and carries an excellent prognosis.

Prenatal risk factors of wheezing at the age of four years in Tanzania

BACKGROUND

A study was undertaken to assess the interactions between prenatal exposures, early life infections, atopic predisposition, and allergen exposures in the development of wheezing up to the age of 4 years in a tropical region of Africa.

METHODS

The study subjects comprised children born at the district hospital in Ifakara, Tanzania during a 1 year period who were participating in a trial of iron supplementation and malaria chemoprophylaxis during the first year of life and followed for up to 4 years. From this group of subjects, 658 (79%) participated in the interview at 18 months and 528 (64%) in a second interview at 4 years. Wheezing was measured with the ISAAC questionnaire. A hospital based inpatient and outpatient surveillance system was set up to document all attendance by study children for any cause, including episodes of clinical malaria and lower respiratory tract infections. Total IgE levels and malaria parasites were measured in maternal and cord blood. Total IgE was also measured at 18 months of age. Indoor environmental levels of Der p I and Fel d I were determined using an enzyme linked immunosorbent assay at the same time as the interview at the age of 18 months.

RESULTS

The prevalence of wheezing at 4 years is common in Ifakara (14%, range 13-15%). The presence of malaria parasites in cord blood (odds ratio, OR = 6.84, 95% CI 1.84 to 24.0) and maternal asthma (OR = 8.47, 95% CI 2.72 to 26.2) were positively associated with wheezing at the age of 4 years, and cord blood total IgE was negatively associated (OR = 0.24, 95% CI 0.07 to 0.85) (all p<0.05). Parasitaemia at birth was not related to total IgE levels in cord blood (p=0.6). Clinical episodes of malaria during infancy were not associated with wheezing, and nor were levels of indoor aeroallergens.

CONCLUSION

These findings suggest that events occurring during pregnancy may play a role in the future appearance of wheezing, although the results must be interpreted with caution because of the small numbers studied.

The association between atopy and asthma in a semirural area of Tanzania (East Africa)

BACKGROUND

Atopy is consistently associated with asthma, except in a study in Africa. We assessed the association between atopy and asthma in women from a semirural area of Tanzania (East Africa).

METHODS

All pregnant women delivering at the district hospital during a 1-year period were recruited (n = 658, 60.6% of those selected). Asthma was investigated by a standard questionnaire and atopy by specific IgE (immunoglobulin E) antibodies to Dermatophagoides pteronyssinus (Der p 1) and cockroach.

RESULTS

The prevalence of wheezing chest was 10.7%; of asthma, 3.5%. Levels of specific IgE of >0.35 kU/l (73%) and high levels of total IgE (62% higher than 1000 kU/l) were highly prevalent. Specific IgE antibody levels in sera were not associated with asthma (3.8% of women with negative specific IgE to any antigen had asthma in comparison to 4.0% of women with positive specific IgE; odds ratio [OR] = 1.06, 0.35-3.22). Total IgE was not different between women with asthma and women without asthma (P=0.36).

CONCLUSIONS

In tropical regions, the association between allergy and asthma is complex, and specific IgE reactivity to environmental allergens may not be related to asthma.

Monoclonal antibodies against hepatitis B s antigen: production, characterization, and use for diagnosis

Three different hybridoma clones secreting anti-HBsAg antibody were constructed by fusing cells of mouse myeloma line Ag8-X63 with splenocytes from BALB/c mice immunized with recombinant HBsAg and natural HBV. The monoclonal antibodies obtained were characterized immunologically, and two were used to develop UMELISA for detection of HBsAg. This monoclonal assay enabled the detection of 0.1 UPE/mL with reference to the standard of the Paul Ehrlich Institute (Frankfurt, Germany). The assay compared well with a commercially available kit (UMELISA HBsAg) and was used for detection of HBsAg in blood donors.

Use of nonpreserved human amniotic membrane for the reconstruction of the ocular surface

PURPOSE

To describe the use of nonpreserved human amniotic membrane (NP-AMT) as an alternative to preserved human amniotic membrane (AMT) for the reconstruction of the ocular surface in several diseases.

METHODS

NP-AMT was used in the treatment of five patients with the following diseases: noninvasive conjunctival squamous cell carcinoma, corneal persistent epithelial defect, severe alkali burn, near total limbal deficiency secondary to multiple surgeries, and ocular cicatricial pemphigoid. In some cases, a limbal autograft or allograft was employed simultaneously, sutured on top of the NP-AMT. All sutures were made with 10-0 Nylon and were removed at two weeks.

RESULTS

Ocular surface was satisfactorily reconstructed, eyes were quiet, and patients were comfortable despite prolonged deepithelialization in some cases. There was a case of a limbal autograft ischemia--in the burned patient--that caused partial corneal conjunctivalization. Initially, the NP-AMT looks thickened but thins around the fifth day and looks similar to AMT.

CONCLUSION

Results using NP-AMT are similar to those of AMT. It is a good alternative and it is easily obtained in places were AMT is not available or is too expensive to procure.

African children with malaria in an area of intense Plasmodium falciparum transmission: features on admission to the hospital and risk factors for death

Malaria remains the most important parasitic cause of mortality in humans. Its presentation is thought to vary according to the intensity of Plasmodium falciparum transmission. However, detailed descriptions of presenting features and risk factors for death are only available from moderate transmission settings. Such descriptions help to improve case management and identify priority research areas. Standardized systematic procedures were used to collect clinical and laboratory data on 6,624 children admitted to hospital over a 1-year period in an intensely malarious part of Tanzania. Frequencies of signs and symptoms were calculated and their association with a fatal outcome was assessed using multivariate logistic regression. There were 72 deaths among 2,432 malaria cases (case fatality rate [CFR] = 3.0%); 44% of the cases and 54% of the deaths were in individuals less than 1 year of age. There was no association between level of parasitemia and CFR. Increased risk of dying was independently found in all children with hypoglycemia (odds ratio [OR] = 6.7, 95% confidence interval [CI] = 3.9-11.7), in children 1-7 months of age with tachypnea (OR = 8.8, 95% CI = 2.6-30.5) and dehydration (OR = 5.0, 95% CI = 1.9-14.2), and in children 8 months to 4 years of age with chest indrawing (OR = 4.7, 95% CI = 2.0-11.2) and inability to localize a painful stimulus (OR = 6.9, 95% CI = 2.9-16.5). Children in the bottom quartile of weight-for-age were more likely to die (OR = 2.1, 95% CI = 1.3-3.5). Eight percent of the malaria cases had severe anemia (packed cell volume < 15%) but 24% received a blood transfusion. The epidemiology of malaria disease may be more complex than previously thought. Improved case management in a wide variety of health facilities may result from adequate identification and treatment of dehydration and hypoglycemia. Transfusion-requiring anemia is a major problem and sustainable, effective preventive measures are urgently needed.

Prevalence and mother-to-infant transmission of hepatitis viruses B, C, and E in Southern Tanzania

Hepatitis B and C markers were tested in 980 pregnant women, in the infants born to infected mothers, and in a random sample of 42 and 50, respectively, children born to uninfected mothers in Tanzania. Sixty-two women (6.3%) were positive for HBsAg and 15 (24%) were HBeAg-seropositive. Anti-HCV was detected in 49 women (5%), 15 (31%) of whom had detectable viremia. HCV RNA serum levels were low and only genotype 4 was identified. Sixty-six women (6.7%) were positive for anti-HIV, six of whom were coinfected with HBV and one with HCV. Anti-HEV was negative in the 180 women tested. At 8 months of age, HBsAg was detected in 8% and 2% of children born to HBV-infected and noninfected mothers, respectively (P = 0.2). Corresponding figures at 18 months of age were 31% and 21% (P = 0.3). When tested at 2 months of age, HCV RNA was not detected in any of the 43 children born to anti-HCV-positive mothers nor in any of 50 children born to anti-HCV-negative mothers. At 18 months, only one child, born to an anti-HCV-positive mother, had detectable HCV RNA. None of the infants born to women with HIV coinfection were infected with hepatitis viruses. This study suggests that exposure to HEV does not occur in southern Tanzania. The prevalence of current HBV infection in pregnant women from rural Tanzania is lower than in other sub-Saharan areas. In early childhood, HBV infection appears to occur by horizontal rather than maternofilial mechanisms of transmission. The prevalence of HCV infection is similar to that in other African countries. The results of this study show for the first time in Africa that mother-to-infant transmission does not play a significant role in the acquisition of HCV infection.

Changes in the performance of parkinsonian patients and normal aged on the Benton Visual Retention Test

Performance on the Benton Visual Retention Test was compared between those with Parkinson's disease (PD) and age-equivalent controls. The major difference between groups was that those with PD showed an increase in figural reproduction errors between test periods spaced six months apart, while controls showed little increase in errors over this time and made fewer errors at each time of testing. Age and IQ accounted for major proportions of variance in performance for both groups (about 50%), far more than that attributable to group membership. Within the PD group, however, age and disease onset were confounded (r = .92), indicating that age as a variable is quite when disease onset is considered. The results support the notion that PD is associated with change in visual-spatial memory, beyond that predicted by age per se.

Traumatic aneurysms of the cerebral vessels

✓ Four cases of traumatic intracranial aneurysms are presented and the pathology and pathophysiology discussed. Two were successfully treated by direct surgical attack. The diagnosis of traumatic aneurysm should be suspected when a patient has an episode of intracranial hemorrhage after a head injury. The outcome of bleeding episodes is fatal in a significant number of cases. Surgery to obliterate the aneurysm is the treatment of choice.