Epileptiform syndrome in rats produced by injecting tetanus toxin into the hippocampus

An epileptiform syndrome in rats produced by injecting small doses (a few (mouse)LD50) of tetanus toxin into the hippocampus is described. The animals had intermittent seizures, with at least a superficial resemblance to human epilepsy, for some weeks but they eventually recovered. They were hyperkinetic for several weeks after the injection of toxin, and showed intermittent aggressive behaviour. Control animals which received similar injections of tetanus toxin first neutralised with antitoxin did not have seizures, and their behaviour appeared normal. EEG recordings showed characteristic seizure activity. Histological examination of the site of injection showed very little morphological damage.

Pathogenesis of capsular opacification after extracapsular cataract extraction. An animal model

Opacification of the posterior capsule is the most common post-operative complication of extracapsular cataract surgery. We studied the sequential changes in the posterior capsule of the aphakic cat and monkey after extracapsular surgery using light microscopy, scanning electron microscopy, and transmission electron microscopy. In the cat, but not the monkey, there was proliferation of a pigment-containing membrane arising from the iris root and ciliary body, and extending onto the residual lens capsule. In both animals there was transformation of residual lens epithelial cells to fibroblasts which contain contractile elements (myofibroblasts) and are associated with collagen deposition. In the cat, pigment epithelial cells from the iris or ciliary body, as well as the transformed lens epithelial cells, contributed to late opacification of the posterior capsule.

Kangaroo Mother Care in very low birth weight infants

OBJECTIVE

This study was conducted (i) to study through a randomized control trial the effect of Kangaroo Mother Care (KMC) on breast feeding rates, weight gain and length of hospitalization of very low birth neonates and (ii) to assess the acceptability of Kangaroo Mother Care by nurses and mothers.

METHODS

Babies whose birth weight was less than 1500 Grams were included in the study once they were stable. The effect of Kangaroo Mother Care on breast feeding rates, weight gain and length of hospitalization of very low birth weight neonates was studied through a randomized control trial in 28 neonates. The Kangaroo group (n = 14) was subjected to Kangaroo Mother Care of at least 4 hours per day in not more than 3 sittings. The babies received Kangaroo Care after shifting out from NICU and at home. The control group (n = 14) received only standard care (incubator or open care system). Attitude of mothers and nurses towards KMC was assessed on Day 3 +/- 1 and on day 7 +/- 1 after starting Kangaroo Care in a questionnaire using Likert's scale.

RESULTS

The results of the clinical trial reveal that the neonates in the KMC group demonstrated better weight gain after the first week of life (15.9 +/- 4.5 gm/day vs. 10.6 +/- 4.5 gm/day in the KMC group and control group respectively p < 0.05) and earlier hospital discharge (27.2 +/- 7 vs. 34.6 +/- 7 days in KMC and control group respectively, p < 0.05). The number of mothers exclusively breastfeeding their babies at 6 week follow-up was double in the KMC group than in the control group (12/14 vs. 6/14) (p < 0.05).

CONCLUSION

KMC managed babies had better weight gain, earlier hospital discharge and, more impressively, higher exclusive breast-feeding rates. KMC is an excellent adjunct to the routine preterm care in a nursery.

Therapeutic lymphangiogenesis ameliorates established acute lung allograft rejection

Lung transplantation is the only viable option for patients suffering from otherwise incurable end-stage pulmonary diseases such as chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis. Despite aggressive immunosuppression, acute rejection of the lung allograft occurs in over half of transplant recipients, and the factors that promote lung acceptance are poorly understood. The contribution of lymphatic vessels to transplant pathophysiology remains controversial, and data that directly address the exact roles of lymphatic vessels in lung allograft function and survival are limited. Here, we have shown that there is a marked decline in the density of lymphatic vessels, accompanied by accumulation of low-MW hyaluronan (HA) in mouse orthotopic allografts undergoing rejection. We found that stimulation of lymphangiogenesis with VEGF-C156S, a mutant form of VEGF-C with selective VEGFR-3 binding, alleviates an established rejection response and improves clearance of HA from the lung allograft. Longitudinal analysis of transbronchial biopsies from human lung transplant recipients demonstrated an association between resolution of acute lung rejection and decreased HA in the graft tissue. Taken together, these results indicate that lymphatic vessel formation after lung transplantation mediates HA drainage and suggest that treatments to stimulate lymphangiogenesis have promise for improving graft outcomes.

A Comprehensive Review of Manifestations of Novel Coronaviruses in the Context of Deadly COVID-19 Global Pandemic

Since December 2019, the global pandemic caused by the highly infectious novel coronavirus 2019-nCoV (COVID-19) has been rapidly spreading. As of April 2020, the outbreak has spread to over 210 countries, with over 2,400,000 confirmed cases and over 170,000 deaths.1 COVID-19 causes a severe pneumonia characterized by fever, cough and shortness of breath. Similar coronavirus outbreaks have occurred in the past causing severe pneumonia like COVID-19, most recently, severe acute respiratory syndrome coronavirus (SARS-CoV) and middle east respiratory syndrome coronavirus (MERS-CoV). However, over time, SARS-CoV and MERS-CoV were shown to cause extrapulmonary signs and symptoms including hepatitis, acute renal failure, encephalitis, myositis and gastroenteritis. Similarly, sporadic reports of COVID-19 related extrapulmonary manifestations emerge. Unfortunately, there is no comprehensive summary of the multiorgan manifestations of COVID-19, making it difficult for clinicians to quickly educate themselves about this highly contagious and deadly pathogen. What is more, is that SARS-CoV and MERS-CoV are the closest humanity has come to combating something similar to COVID-19, however, there exists no comparison between the manifestations of any of these novel coronaviruses. In this review, we summarize the current knowledge of the manifestations of the novel coronaviruses SARS-CoV, MERS-CoV and COVID-19, with a particular focus on the latter, and highlight their differences and similarities.

Pulmonary macrophages are attracted to inhaled particles through complement activation

Pulmonary macrophages play a central role in clearing inhaled particles from the lung. Previously, we showed that inhaled asbestos fibers activate complement-dependent chemotactic factors on alveolar surfaces to facilitate macrophage recruitment to sites of fiber deposition. In the studies presented here, we have tested a variety of inorganic particles for complement activation in vitro and correlated these data with results on particle-induced macrophage accumulation in vivo. We found that significant chemotactic activity was activated in rat serum and concentrated lavaged proteins by chrysotile and crocidolite asbestos, iron-coated chrysotile asbestos, fiberglass, and wollastonite fibers, as well as by carbonyl iron and zymosan particles. Ash from the Mt. St. Helens volcano did not induce chemotactic activity in either the serum or lavaged proteins. Rats were exposed to brief aerosols of each of the particles listed above (except zymosan). All the particle types studied were deposited primarily at first alveolar duct bifurcations. In addition, all of the particles, except Mt. St. Helens ash, induced at 48 h postexposure significant accumulations of macrophages at these sites. Time-course studies of carbonyl iron particle exposure demonstrated that iron induced a rapid macrophage response, but both particles and phagocytic macrophages were cleared from alveolar surfaces within 8 days after exposure. The Mt. St. Helens ash induced no macrophage accumulation at any time postexposure. We conclude that particles with a wide variety of physical characteristics are capable of activating complement and consequently attracting macrophages, both in vitro and in vivo. We suggest that complement activation is a mechanism through which pulmonary macrophages can detect inhaled particles on alveolar surfaces.

Effect of population ageing on emergency department speed and efficiency: a historical perspective from a district general hospital in the UK

OBJECTIVE

To examine changes in the rate of seeing patients between 1990 and 2004 and to see whether performance might be related to patient age, using data held on the patient administration system.

METHOD

Data collected in 1990 were compared with those collected in 2004. Age related data were examined for the following parameters: the number of patients arriving by ambulance; the time taken to process the attendance; the number of investigations; the number of emergency admissions; and the length of inpatient stay.

RESULTS

Emergency department (ED) performance has fallen markedly since 1990. Between 1990 and 2004, there was a 54% increase in total patients with a disproportionate 198% increase in patients aged more than 70 years, including a 671% increase in those aged more than 90 years. The time taken to manage patients increased with age. In 2004, there was a marked rise in investigation rates, and the probability of having investigations increased with age. In 2004, older patients (aged more than 70 years) were 4.9 times more likely to require admission to hospital than younger patients (aged 30 years or less). Their average length of stay was 6.9 times longer. Younger patients were 3.3 times more numerous than older patients but older patients occupied 9.8 times more emergency bed days.

CONCLUSIONS

Pressure on emergency care is associated with a disproportionate increase in the number of elderly patients and with an increased tendency to investigate them. Population ageing is of central importance in planning health services.

Sialic acid mediates the initial binding of positively charged inorganic particles to alveolar macrophage membranes

Pulmonary macrophages phagocytize inhaled particles and are postulated to play a role in the development of pulmonary interstitial fibrogenesis. The basic biologic mechanisms through which inhaled particles bind to macrophage membranes and subsequently are phagocytized remain unclear. We hypothesize that positively charged particles bind to negatively charged sialic acid (SA) residues on macrophage membranes. Alveolar Macrophages (AM) were collected by saline lavage from normal rat lungs. The cells adhered to plastic coverslips in serum-free phosphate buffered saline at 37 degrees C for 45 min and then were maintained at 4 degrees C for the binding experiments. Even distribution of SA groups on AM surfaces was demonstrated by scanning electron microscopy of wheat germ agglutinin (WGA) conjugated to 50 nm gold spheres. The WGA is a lectin that binds specifically to sialic acid, and pretreatment of AM with this lectin prevented the binding of positively charged carbonyl iron (C-Fe) spheres, aluminum (Al) spheres, and chrysotile asbestos fibers to AM surfaces. Limulus protein, another lectin with binding specificity for SA, similarly blocked the binding of positively charged spheres and chrysotile asbestos fibers but not negatively charged glass spheres or crocidolite asbestos fibers. Con A and ricin, lectins that bind to mannose and galactose residues, respectively, did not block particle binding. When both positively charged iron spheres and negatively charged glass spheres were prebound to AM membranes, subsequent treatment with WGA displaced only the positively charged spheres from macrophage surfaces. Con A and ricin had no effect on prebound positively charged C-Fe and Al spheres.(ABSTRACT TRUNCATED AT 250 WORDS)

Metabolic Reprogramming as a Driver of Fibroblast Activation in PulmonaryFibrosis

Pulmonary fibrosis refers to a heterogeneous group of disorders that scar the lung, most often irreversibly. To date, there are limited effective treatments for these conditions, despite decades of research in this area of investigation. In pulmonary fibrosis, the principle cell responsible for producing the vast majority of scar tissue is the fibroblast, making these cells ideally suited for drug targeting. For decades, the major experimental approach to blocking the activity of lung fibroblasts has been either to inhibit the interaction of fibroblast growth factors with their receptors or interfere with downstream effector molecules regulating extracellular matrix production. However, emerging evidence now indicates that lung fibroblasts also undergo dramatic metabolic reprogramming in the setting of growth factor stimulation. These discoveries, along with preclinical investigations showing marked reductions in lung fibrosis after targeting specific metabolic pathways, has led to a total rethinking of drug development in the pulmonary fibrosis field. Here, we review the major metabolic pathways and highlight some of the key metabolic events that occur in the transition of fibroblasts from quiescent to activated states. Moreover, we discuss the emerging evidence linking changes in fibroblast metabolism to pulmonary fibrosis and propose how targeting specific metabolic pathways could be employed in the treatment of fibrotic lung diseases.

Behavioural correlates of an experimental hippocampal epileptiform syndrome in rats

Experiments are reported describing assessment of abnormal behaviour of rats in which a chronic epileptiform syndrome has been induced by the injection of tetanus toxin bilaterally into their hippocampi. The abnormal behaviour included hyper-reactivity to a novel environment, intermittent aggression on handling, and abnormally passive response to a strange rat introduced into their home cage. In animals with unilateral injection of toxin, electrical records from the hippocampi have been obtained. They illustrated bilaterally simultaneous discharges and also some independence between the two hippocampi. The discharges were accompanied by overt signs of complex partial seizures during the first few weeks of the syndrome but later occurred without motor signs. In this later stage the rats were somewhat resistant to the convulsant effects of pentylenetetrazol.

Short telomeres, telomeropathy, and subclinical extrapulmonary organ damage in patients with interstitial lung disease

BACKGROUND

Human telomere disease consists of a wide spectrum of disorders, including pulmonary, hepatic, and bone marrow abnormalities. The extent of bone marrow and liver abnormalities in patients with interstitial lung disease (ILD) and short telomeres is unknown.

METHODS

The lung transplant clinic established a prospective protocol to identify short telomeres in patients with ILD not related to connective tissue disease or sarcoidosis. Patients with short telomeres underwent bone marrow biopsies, liver biopsies, or both as part of the evaluation for transplant candidacy.

RESULTS

One hundred twenty-seven patients met ILD categorization for inclusion. Thirty were suspected to have short telomeres, and 15 had the diagnosis confirmed. Eight of 13 (53%) patients had bone marrow abnormalities. Four patients had hypocellular marrow associated with macrocytosis and relatively normal blood counts, which resulted in changes to planned immunosuppression at the time of transplant. Four patients with more severe hematologic abnormalities were not listed because of myelodysplastic syndrome (two); monoclonal gammopathy of unclear significance (one); and hypocellular marrow, decreased megakaryocyte lineage associated with thrombocytopenia (one). Seven patients underwent liver biopsies, and six had abnormal liver pathology. These abnormalities did not affect listing for lung transplant, and liver biopsies are no longer routinely obtained.

CONCLUSIONS

Subclinical bone marrow and liver abnormalities can be seen in patients with ILD and short telomeres, in some cases in the absence of clinically significant abnormalities in peripheral blood counts and liver function tests. A larger study examining the implication of these findings on the outcome of patients with ILD and short telomeres is needed.

Effects of silica on the composition of the pulmonary extracellular lining

The effects of intratracheally injected silica on lung weights and on alveolar macrophages, polymorphonuclear leukocytes, phospholipid, protein, N-acetyl-beta-glucosaminidase, and alkaline phosphatase of the extracellular lining of rat lungs were studied as functions of dose and time. All of these parameters increased with time up to 12 days after a single injection of silica (200 mg/kg) and showed a dose dependence in their responses. Extracellular soluble protein increased 19.8-fold from 1.9 to 37.6 mg/pair of lungs. The composition of the extracellular soluble protein was very similar to that found in normal lungs as determined with two-dimensional-polyacrylamide gel electrophoresis. Although most of the soluble proteins in lavage effluents were similar to those found in serum, several serum proteins were absent, indicating that the selectivity of the lungs for certain serum proteins was maintained after treatment with silica. Increases in extracellular soluble proteins could not be accounted for by damage to the blood/air barrier. Extracellular phospholipid increased 12.1-fold from 1.74 to 21.1 mg/pair of lungs. The phosphatidylcholine content of this phospholipid resembled that of normal pulmonary surfactant but was different from that in free cells lavaged from the lungs of control and silica-treated rats. Increases in extracellular phospholipid were probably due to silica effects on the surfactant system and not to destruction of or release by free cells in the alveoli. N-Acetyl-beta-glucosaminidase and alkaline phosphatase increased approximately 33- and 6-fold, respectively, in response to silica. The number of alveolar macrophages and polymorphonuclear leukocytes increased 1.5- and 75-fold, respectively. Calculation of partial correlations revealed statistically significant relationships among extracellular phospholipids, soluble proteins, and the two hydrolytic enzymes, suggesting that these components were being released into the lung lining from a common source or by a common mechanism.

Perforation of the oesophagus and aorta after eating fish: an unusual cause of chest pain

This report describes perforation of the oesophagus after eating fish complicated by perforation of the aorta six days later. The patient had not knowingly swallowed a fish bone. Aorto-oesophageal fistula is almost universally fatal. In the case described here, the fistula was demonstrated on contrast computed tomography before surgery, thus informing surgical management. The patient is the eighth reported survivor.

Radiation-induced impairment in lung lymphatic vasculature

BACKGROUND

The lymphatic vasculature has been shown to play important roles in lung injury and repair, particularly in lung fibrosis. The effects of ionizing radiation on lung lymphatic vasculature have not been previously reported.

METHODS AND RESULTS

C57Bl/6 mice were immobilized in a lead shield exposing only the thoracic cavity, and were irradiated with a single dose of 14 Gy. Animals were sacrificed and lungs collected at different time points (1, 4, 8, and 16 weeks) following radiation. To identify lymphatic vessels in lung tissue sections, we used antibodies that are specific for lymphatic vessel endothelial receptor 1 (LYVE-1), a marker of lymphatic endothelial cells (LEC). To evaluate LEC cell death and oxidative damage, lung tissue sections were stained for LYVE-1 and with TUNEL staining, or 8-oxo-dG respectively. Images were imported into ImageJ v1.36b and analyzed. Compared to a non-irradiated control group, we observed a durable and progressive decrease in the density, perimeter, and area of lymphatic vessels over the study period. The decline in the density of lymphatic vessels was observed in both subpleural and interstitial lymphatics. Histopathologically discernible pulmonary fibrosis was not apparent until 16 weeks after irradiation. Furthermore, there was significantly increased LEC apoptosis and oxidative damage at one week post-irradiation that persisted at 16 weeks.

CONCLUSIONS

There is impairment of lymphatic vasculature after a single dose of ionizing radiation that precedes architectural distortion and fibrosis, suggesting important roles for the lymphatic circulation in the pathogenesis of the radiation-induced lung injury.

Parasuicide: interaction between inadequate parenting and recent interpersonal stress

We report a controlled study in which we searched for links between early family adversity and recent interpersonal stress in parasuicidal patients. Our subjects reported fewer adverse experiences in childhood than did the younger, predominantly female, patients investigated in previous studies. Nevertheless, 47% of our parasuicidal group, as compared to 19% of control subjects, reported a sequential pattern of relationship difficulties starting in childhood. The pattern of early exposure to neglectful and overprotective parenting followed by recent conflict or separations in adulthood was found to discriminate most clearly between the parasuicidal and control groups. We suggest that factors such as low self-esteem, a sense of helplessness in the face of adversity and an abiding insecurity in intimate relationships may variously account for this heightened vulnerability. We conclude that a history of adverse relationships beginning in childhood should alert primary care-givers to the risk of suicidal behaviour in patients who are exposed to distressing separations or interpersonal conflict.

Fourier transform infrared spectrometry: a versatile technique for real world samples

The versatility of FTIR spectrometry was explored by considering a variety of samples drawn from industrial applications, materials science and biomedical research. These samples included polymeric insulators, bauxite ore, clay, human hair and human skin. A range of sampling techniques suitable for these samples is discussed, in particular FTIR microscopy, FTIR emission spectroscopy, attenuated total reflectance and photoacoustic FTIR spectrometry. The power of modern data processing techniques, particularly multivariate analysis, to extract useful information from spectral data is also illustrated.

Plasma aspirin esterase activity in elderly patients undergoing elective hip replacement and with fractured neck of femur

Plasma aspirin esterase activity was measured in eight elderly patients undergoing elective hip replacement, and in 11 presenting with femoral-neck fracture. Elective hip surgery was associated with a marked and significant decline in esterase, from 330 +/- 35.9 (SE) (nmol salicylate/ml plasma/min) pre-operatively to 236 +/- 35.6 on the third post-operative day, and returning to normal (359 +/- 24.3) at recovery phase. Patients with fractured neck of femur showed a depressed esterase activity on admission (221 +/- 12.7), rising towards normal (290 +/- 15.4) on recovery. All of these changes were accompanied by a marked acute-phase response, both to injury and surgery. The data suggest that elderly patients experiencing injury or undergoing surgery may have significantly impaired drug metabolism, at least as far as this enzyme is concerned.

Facilities for chemical decontamination in accident and emergency departments in the United Kingdom

OBJECTIVE

To audit the facilities for chemical decontamination, with special reference to cyanide poisoning, in all major accident and emergency departments in the UK.

METHOD

A simple postal questionnaire was used to audit planning, premises, equipment, protection for staff, and stocks of specific antidotes to cyanide poisoning.

RESULTS

227 questionnaires from 261 departments (87%) were returned and used in the survey. Of the 227 departments who responded, 151 (66%) had a written plan; 168 (74%) departments had premises for decontamination; 55 (24%) were judged to have satisfactory premises; 146 (64%) departments had a shower or hose for decontamination; 60 (26%) departments had a decontamination trolley suitable for "stretcher" patients; 203 (89%) had some protective equipment for staff but only 77 (34%) had complete protection--that is, goggles, chemical resistant clothing, and breathing apparatus. In the authors' opinion only seven (3%) departments had satisfactory premises and equipment to treat "stretcher" patients and full protection for staff. A further 11 (5%) departments were equipped to manage ambulant patients at a similar level. Some 205 (90%) departments stocked one or more antidotes to cyanide and 77 (34%) stocked all four antidotes. Thirty four (15%) departments held all four antidotes to cyanide and had full protection for staff. Only five (2%) departments had satisfactory premises and equipment to treat "stretcher" patients, full protection for staff, and at least three of four antidotes.

CONCLUSIONS

Most departments had some equipment for chemical decontamination. However, there were major inconsistencies in the range of equipment held and these limited its usefulness. Only a small minority of departments was satisfactorily equipped to deal with a serious chemical incident.

An evaluation of the effectiveness of the Zambian Health Worker Retention Scheme (ZHWRS) for rural areas

BACKGROUND

Zambian Health Workers Retention Scheme (ZHWRS) commenced in 2003. The schemes' original aim was to retain and recruit Zambian doctors in rural and remote districts. The aim of the ZHWRS subsequently expanded to also include other health workers, in either rural or urban areas. The scheme was formulated to address, in part, the drastic shortage of health workers.

OBJECTIVES

To evaluate the effectiveness of the ZHWRS in achieving its aim.

METHODS

The data on the number of health workers recruited by the ZHWRS and the spatial distribution of them was reviewed. A survey of health workers was undertaken to elicit their views of their working conditions, their job satisfaction and the effectiveness of retention schemes in retaining or increasing the numbers of and overall satisfaction of health workers.

RESULTS

The ZHWRS has not been successful in recruiting sufficient numbers of health workers to reverse the shortage problem or even to meet the modest targets of the scheme itself. However, these improvements do not decrease the likelihood of Department of Health (DoH) workers leaving their rural based positions.

CONCLUSIONS

The ZHWRS has not fully met either its original or revised aims. The drastic shortage of health workers in Zambia continues.