A genomic screen of autism: evidence for a multilocus etiology

We have conducted a genome screen of autism, by linkage analysis in an initial set of 90 multiplex sibships, with parents, containing 97 independent affected sib pairs (ASPs), with follow-up in 49 additional multiplex sibships, containing 50 ASPs. In total, 519 markers were genotyped, including 362 for the initial screen, and an additional 157 were genotyped in the follow-up. As a control, we also included in the analysis unaffected sibs, which provided 51 discordant sib pairs (DSPs) for the initial screen and 29 for the follow-up. In the initial phase of the work, we observed increased identity by descent (IBD) in the ASPs (sharing of 51.6%) compared with the DSPs (sharing of 50.8%). The excess sharing in the ASPs could not be attributed to the effect of a small number of loci but, rather, was due to the modest increase in the entire distribution of IBD. These results are most compatible with a model specifying a large number of loci (perhaps >/=15) and are less compatible with models specifying </=10 loci. The largest LOD score obtained in the initial scan was for a marker on chromosome 1p; this region also showed positive sharing in the replication family set, giving a maximum multipoint LOD score of 2.15 for both sets combined. Thus, there may exist a gene of moderate effect in this region. We had only modestly positive or negative linkage evidence in candidate regions identified in other studies. Our results suggest that positional cloning of susceptibility loci by linkage analysis may be a formidable task and that other approaches may be necessary.

Superior sensitivity of conjugates of horseradish peroxidase with wheat germ agglutinin for studies of retrograde axonal transport

We have compared the retrograde axonal transport of horseradish peroxidase (HRP), to the retrograde transport of HRP conjugated with wheat germ agglutinin (WGA). Morphometric studies have shown that WGA-HRP conjugates were 40 times more sensitive than free HRP, in the tracing of retrograde connections from the rat submandibular gland to the superior cervical ganglion. Also, WGA-HRP was more sensitive than free HRP in the tracing of retrograde connections from the rat tongue to the hypoglossal nucleus. Our findings with WGA-HRP are consistent with the observations by Schwab et al. who reported (-125I) WGA is a highly sensitive retrograde tracer (Brain Research 152:145, 1978 (22)).

Wernicke's encephalopathy: a more common disease than realised. A neuropathological study of 51 cases

During a four year peirod, 51 cases of Wernicke's encephalopathy were diagnosed at necropsy, an incidence of 1.7% of all necropsies performed at the Royal Perth Hospital and by the Perth City coroner. Only seven had been diagnosed during life. Many of the patients died suddenly and unexpectedly, apparently as a result of haemorrhagic brainstem lesions, typical of acute Wernicke's encephalopathy, since no other cause of death was found. There was a high incidence of epilepsy and four patients were hypothermic. The diagnosis of Wernicke's encephalopathy may be missed at necropsy unless the brain is examined histologically. Cerebral atrophy and ventricular dilatation were common findings. This is a more common disease than is generally recognised, one which can be readily treated and, more importantly, prevented by adequate nutrition.

The neuropathology of alcohol-specific brain damage, or does alcohol damage the brain?

The aim of this review is to identify neuropathological changes that are directly related to the long-term use of excessive amounts of alcohol (ethanol). There is still debate as to whether alcohol per se causes brain damage. The main problem has been to identify those lesions caused by alcohol itself and those caused by other common alcohol-related factors, principally thiamin deficiency. Careful selection and classification of alcoholic cases into those with and without these complications, together with detailed quantitative neuropathological analyses, has provided us with useful data. There is brain shrinkage in uncomplicated alcoholics which can largely be accounted for by loss of white matter. Some of this damage appears to be reversible. However, alcohol-related neuronal loss has been documented in specific regions of the cerebral cortex (superior frontal association cortex), hypothalamus (supraoptic and paraventricular nuclei), and cerebellum. The data is conflicting for several regions: the hippocampus, amygdala and locus ceruleus. No change is found in the basal ganglia, nucleus basalis, or serotonergic raphe nuclei. Many of the regions that are normal in uncomplicated alcoholics are damaged in those with the Wernicke-Korsakoff syndrome. Dendritic and synaptic changes have been documented in uncomplicated alcoholics and these, together with receptor and transmitter changes, may explain functional changes and cognitive deficits that precede the more severe structural neuronal changes. The pattern of damage appears to be somewhat different and species-specific in animal models of alcohol toxicity. Pathological changes that have been found to correlate with alcohol intake include white matter loss and neuronal loss in the hypothalamus and cerebellum.

The incidence of Wernicke's encephalopathy in Australia--a neuropathological study of 131 cases

In a nine year necropsy study in Western Australia, the incidence of Wernicke's encephalopathy was 2.8%. The incidence appears to be increasing. Although Wernicke's encephalopathy is a nutritional disorder, the majority of cases occur in the alcoholic population. Only 20% of the 131 cases studied had been diagnosed clinically as Wernicke's encephalopathy. This large discrepancy between numbers of cases diagnosed clinically and pathologically suggests that chronic Wernicke's encephalopathy, which comprised 83% of the cases, may be the end result of repeated subclinical episodes of Wernicke's encephalopathy. Thus, Wernicke's encephalopathy could be considered a "progressive" disorder and as patients respond well to thiamine replacement therapy, early diagnosis is important. Alternatively, prevention by vitamin enrichment of alcoholic beverages may have to be considered in an attempt to minimise the social and economic impact of Wernicke's encephalopathy on Western society.

Are we drinking our neurones away?

A quantitative neuropathological necropsy study of the human cerebral cortex showed that the number of cortical neurones in the superior frontal cortex in chronic alcoholic patients is significantly reduced compared with that in controls matched for age and sex. The number of neurones in the motor cortex did not differ significantly between the controls and alcoholics, but in both cortical regions there was evidence that alcoholic patients had smaller (shrunken) neurones than controls. Further studies are necessary to identify other regions of the cerebral cortex that are selectively damaged in brain damage associated with alcohol.

Brain atrophy in chronic alcoholic patients: a quantitative pathological study

There are essentially no objective neuropathological data on brain atrophy in chronic alcoholic patients despite numerous neuroradiological studies which show a high incidence of shrinkage or atrophy. Therefore measurements were made of the intracranial volume (ICV) and brain volume (BV) in a necropsy study of 25 chronic alcoholic patients and 44 controls. The pericerebral space (PICS) was calculated according to the formula (formula; see text) The PICS will increase in patients with brain atrophy since the ICV remains constant throughout life. The mean PICS value was 8.3% in controls, 11.3% in the alcoholic group, 14.7% in alcoholics with superimposed Wernicke's encephalopathy (thiamine deficiency) and 16.2% in those alcoholics with associated liver disease. Thus there was a statistically significant loss of brain tissue in chronic alcoholic patients which appeared to be more severe in those with associated nutritional vitamin deficiencies or alcoholic liver disease.

Permacol: clinical experience with a new biomaterial

Permacol (Tissue Science Laboratories plc, Aldershot, Hants) is a new biomaterial which combines the strength and permanence of synthetic surgical repair materials with the biocompatibility of natural materials. This article examines the clinical application of Permacol in a range of different surgical procedures.

Patterns of neuronal loss in the cerebral cortex in chronic alcoholic patients

A loss of neurones from the frontal cortex of chronic alcoholic patients has recently been documented. In addition to this loss of neurones there was found to be a reduction in the mean size of the neuronal soma in both the superior frontal and motor cortices. This could be explained on the basis of a selective loss of larger neurones rather than a general shrinkage of all neurones. This population of large neurones (greater than 90 microns 2) has been recognised as being more vulnerable in both Alzheimer's disease and the normal ageing process. Neurones in 2 size categories (41-90 microns 2 and greater than 90 microns 2) were counted in the superior frontal and motor cortices of age- and sex-matched controls and alcoholics. There was found to be a significant reduction in the number of large neurones in the superior frontal cortex, whilst no change in number was seen in the motor cortex. The possibility that neurones in particular layers of the cortex are more severely affected in alcohol abuse was also considered. The cortex was divided into 3 layers and the number of neurones and glia in each determined. No pattern of regional neuronal loss could be distinguished.

Pyrroles and other heterocycles as inhibitors of p38 kinase

Investigation of furans, pyrroles and pyrazolones identified 3-pyridyl-2,5-diaryl-pyrroles as potent, orally bioavailable inhibitors of p38 kinase. 3-(4-pyridyl-2-(4-fluoro-phenyl)-5-(4-methylsulfinylphenyl)-pyrrol e (L-167307) reduces secondary paw swelling in the rat adjuvant arthritis model: ID50 = 7.4 mg/kg/b.i.d.

Changes in the basal dendrites of cortical pyramidal cells from alcoholic patients--a quantitative Golgi study

Although a variety of pathological changes have been described in the brains of chronic alcoholic patients, there have been no studies which have addressed the question of alterations in cortical neuronal dendritic arborisation. Loss of neurons from the superior frontal gyrus and shrinkage of neurons from both the superior frontal gyrus and motor cortex has been documented in chronic alcoholic patients; these areas were chosen for this study. Using a modified rapid Golgi technique the basal dendritic arborisation of layer III pyramidal neurons was compared in 15 male alcoholic patients and 15 age-matched male controls. All parameters measuring basal dendritic arborisation were significantly less in the alcoholic cases for both the superior frontal and motor cortices. Changes in the arbor are in the terminal branches, which is consistent with other models of dendritic plasticity. Such changes may explain both permanent and reversible functional deficits in chronic alcoholic patients.

pH measurement as quality control on human post mortem brain tissue: a study of the BrainNet Europe consortium

AIMS

Most brain diseases are complex entities. Although animal models or cell culture experiments mimic some disease aspects, human post mortem brain tissue remains essential to advance our understanding of brain diseases using biochemical and molecular techniques. Post mortem artefacts must be properly understood, standardized, and either eliminated or factored into such experiments. Here we examine the influence of several premortem and post mortem factors on pH, and discuss the role of pH as a biochemical marker for brain tissue quality.

METHODS

We assessed brain tissue pH in 339 samples from 116 brains provided by 8 different European and 2 Australian brain bank centres. We correlated brain pH with tissue source, post mortem delay, age, gender, freezing method, storage duration, agonal state and brain ischaemia.

RESULTS

Our results revealed that only prolonged agonal state and ischaemic brain damage influenced brain tissue pH next to repeated freeze/thaw cycles.

CONCLUSIONS

pH measurement in brain tissue is a good indicator of premortem events in brain tissue and it signals limitations for post mortem investigations.

Influence of hospital and clinician workload on survival from colorectal cancer: cohort study

OBJECTIVE

To determine whether clinician or hospital caseload affects mortality from colorectal cancer.

DESIGN

Cohort study of cases ascertained between 1990 and 1994 by a region-wide colorectal cancer register.

OUTCOME MEASURES

Mortality within a median follow up period of 54 months after diagnosis.

RESULTS

Of the 3217 new patients registered over the period, 1512 (48%) died before 31 December 1996. Strong predictors of survival both in a logistic regression (fixed follow up) and in a Cox's proportional hazards model (variable follow up) were Duke's stage, the degree of tumour differentiation, whether the liver was deemed clear of cancer by the surgeon at operation, and the type of intervention (elective or emergency and curative or palliative intent). In a multilevel model, surgeon's caseload had no significant effect on mortality at 2 years. Hospital workload, however, had a significant impact on survival. The odds ratio for death within 2 years for cases managed in a hospital with a caseload of between 33 and 46 cases per year, 47 and 54 cases per year, and >/=55 cases per year (compared to one with </=23 cases per year) were respectively 1.48 (95% confidence interval 1.03 to 2.13), 1.52 (1.08 to 2.13), and 1.18 (0.83 to 1.68).

CONCLUSIONS

There was no detectable caseload effect for surgeons managing colorectal cancer, but survival of patients treated in hospitals with caseloads above 33 cases per year was slightly worse than for those treated in hospitals with fewer caseloads. Imprecise measurement of clinician specific "events rates" and the lack of routinely collected case mix data present major challenges for clinical audit and governance in the years ahead.

Emergency contraception: advance provision in a young, high-risk clinic population

OBJECTIVE

To assess whether advance provision of emergency contraception increases its use and whether it has secondary effects on regular contraceptive use.

METHODS

We conducted a controlled trial of female clients, aged 16-24 years, who attended a publicly funded family planning clinic. Women were systematically assigned to receive an advance provision of emergency contraception and education (treatment) or education only (control). Among 263 participants enrolled (133 treatment, 130 control), follow-up was completed in 213 (111 treatment, 102 control). The main outcome measures were emergency contraception knowledge and use, frequency of unprotected sex, and pattern of contraceptive use in the past 4 months.

RESULTS

Participants were aware of emergency contraception at follow-up, but the treatment group was three times as likely to use it (P =.006). Although the treatment group did not report higher frequencies of unprotected sex than the control group, women in the treatment group (28%) were more likely than those in the control group (17%) to report using less effective contraception at follow-up compared with enrollment (P =.05). The proportion of women in both groups who reported consistent pill use increased from enrollment to follow-up (34% versus 45%); however, the control group (58%) was more likely than the treatment group (32%) to report consistent pill use at follow-up (P =.03).

CONCLUSION

Use of emergency contraception was increased by providing it in advance, but not by education alone. Changes to less effective contraceptive methods and patterns of pill use were potentially negative effects that need to be explored in relation to observed benefits.

Sexual dimorphism of the human corpus callosum from three independent samples: relative size of the corpus callosum

Three independent autopsy samples of brains without apparent neuropathology were studied to ascertain whether there was sexual dimorphism in the human corpus callosum (CC). Using planimetric measurements on midsagittal brain sections, several morphometric features of the CC were studied: total callosal area, maximum dorsoventral splenial width, the posterior one fifth of the total area of the CC (mostly splenium), and brain weight. Ratio data correcting for brain size were also studied. In all samples, absolute brain size was larger in males, and significantly so. Measurements of splenial dorsoventral width were higher in females than males, but not significantly, except in the Australian sample. Total callosal area was absolutely higher in the Australian female sample than in males, and almost equal in the two American samples, without statistically significant differences. The posterior one-fifth area (splenium) was larger for females in each of the samples. The variables which were corrected for brain size were usually significantly larger in females, although this pattern varied in each sample. The statistical pattern of sexual dimorphism for the human CC differs from that found in most other neural structures, such as the amygdaloid nucleus, cerebellum, hippocampus, and thalamus. The absolute sizes of these structures are always significantly larger in males. When corrected for brain size, the relative sizes are not significantly larger. The CC is the only structure to show a larger set of relative measures in females.

Thiamine (vitamin B1) deficiency and associated brain damage is still common throughout the world and prevention is simple and safe!

Many different population groups throughout the world have thiamine deficiency and are at risk of developing severe neurological and cardiac disorders. Alcoholics are most at risk but other important clinical groups should be monitored carefully. The most severe, potentially fatal disease caused by thiamine deficiency is the neurological disorder Wernicke-Korsakoff syndrome. This can be difficult to diagnose and many cases remain undiagnosed. Treatment with thiamine generally results in a dramatic clinical improvement. Thiamine supplementation of stable food products like flour is an effective, simple and safe public health measure that can improve the thiamine status of all population groups.

Differential protein expression in the prefrontal white matter of human alcoholics: a proteomics study

Neuroimaging and post-mortem studies indicate that chronic alcohol use induces global changes in brain morphology, such as cortical and subcortical atrophy. Recent studies have shown that frontal lobe structures are specifically susceptible to alcohol-related brain damage and shrinkage in this area is largely due to a loss of white matter. This may explain the high incidence of cognitive dysfunction observed in alcoholics. Using a proteomics-based approach, changes in protein expression in the dorsolateral prefrontal region (BA9) white matter were identified in human alcoholic brains. Protein extracts from the BA9 white matter of 25 human brains (10 controls; eight uncomplicated alcoholics; six alcoholics complicated with hepatic cirrhosis; one reformed alcoholic) were separated using two-dimensional gel electrophoresis. Overall, changes in the relative expression of 60 proteins were identified (P<0.05, ANOVA) in the alcoholic BA9 white matter. In total, 18 protein spots have been identified using MALDI-TOF; including hNP22, alpha-internexin, transketolase, creatine kinase chain B, ubiquitin carboxy-terminal hydrolase L1 and glyceraldehyde-3-phosphate dehydrogenase. Several of these proteins have been previously implicated in alcohol-related disorders and brain damage. By identifying changes in protein expression in this region from alcoholics, hypotheses may draw upon more mechanistic explanations as to how chronic ethanol consumption causes white matter damage.

An international perspective on the prevalence of the Wernicke-Korsakoff syndrome

In the Western world previous studies have shown that the majority of cases of the Wernicke-Korsakoff syndrome (WKS), which is caused by thiamine deficiency, occur in alcoholics. However, in France, a country with one of the highest per capita consumptions of alcohol, the prevalence of the WKS was found to be only 0.4% in a small retrospective autopsy study. This figure is compared with data sent to the authors by a number of neuropathologists from the U.S.A., Europe, Scandinavia and Australia. There was no obvious correlation between the prevalence rates of the WKS, which were highest in Australia (2.8%-previously published), and per capita consumption of alcohol. Other issues such as diet, National programs for supplementation of foods with thiamine, and drinking habits are considered. The pathological diagnosis of the WKS can often be made on macroscopic examination of the brain after fixation in formalin. The mammillary bodies are smaller than normal in most cases of chronic WKS. However in this study it was found that the most common causes of small mammillary bodies were Alzheimer's disease and atrophy due to transneuronal degeneration secondary to lesions in the hippocampus.

Dystrophic neurite formation associated with age-related beta amyloid deposition in the neocortex: clues to the genesis of neurofibrillary pathology

The formation of dystrophic neurites associated with beta amyloid plaques in Alzheimer's disease (AD) appears to involve a transformation of normal neuronal cytoskeletal proteins. In order to investigate what may be the earliest neuronal changes associated with the development of dystrophic neurites, we have examined the neurochemical profile of abnormal neuritic processes associated with the beta amyloid deposition in non-AD, aged cases. In all non-AD individuals demonstrating some degree of beta amyloid deposition in the superior frontal gyrus, clustered swollen and ring-like structures, located principally in layers II and III, were labeled with antibodies to phosphorylated and nonphosphorylated domains of the middle and high molecular weight neurofilament subunits. These abnormal neurites were not immunolabeled for tau or ubiquitin or stained with thioflavine S. Double labeling for neurofilaments and thioflavine S confirmed that these clusters of dystrophic neurites were associated with plaque-like deposits. These results show that anatomically and neurochemically specific forms of dystrophic neurites can occur in non-AD cases that contain beta amyloid deposition. If these abnormal neurites correspond to an immature form of the dystrophic neurites found in the neuritic plaques of Alzheimer's disease, then neurofibrillary pathology associated with this disease may begin with an initial misprocessing and accumulation of neurofilament proteins. Furthermore, these data are consistent with the proposal that the development of neurofibrillary pathology may begin with neurofilamentous hypertrophy in damaged distal processes followed by reactive changes in the cell bodies of origin of these fibers involving cytoskeletal alterations that ultimately lead to neurofibrillary tangle formation.

An Australian Brain Bank: a critical investment with a high return!

Research into neuropsychiatric disorders, including alcohol-related problems, is limited in part by the lack of appropriate animal models. However, the development of new technologies in pathology and molecular biology means that many more questions can be addressed using appropriately stored human brain tissues. The New South Wales Tissue Resource Centre (TRC) in the University of Sydney (Australia) is a human brain bank that can provide tissues to the neuroscience research community studying alcohol-related brain disorders, schizophrenia, depression and bipolar disorders. Carefully standardised operational protocols and integrated information systems means that the TRC can provide high quality, accurately characterised, tissues for research. A recent initiative, the pre-mortem donor program called "Using our Brains", encourages individuals without neuropsychiatric illness to register as control donors, a critical group for all research. Community support for this program is strong with over 2,000 people registering their interest. Discussed herein are the protocols pertaining to this multifaceted facility and the benefits of investment, both scientific and financial, to neuroscience researchers and the community at large.

Recombinant human interleukin-1 beta-induced increase in levels of proteoglycans, stromelysin, and leukocytes in rabbit synovial fluid

OBJECTIVE

To evaluate the effects of intraarticular injection of recombinant human interleukin-1 beta (IL-1 beta) on levels of proteoglycans, stromelysin, and leukocytes in rabbit synovial fluid (SF), and to determine the effects of leukocyte depletion on SF proteoglycan and stromelysin levels.

METHODS

Levels of leukocytes and of proteoglycans, stromelysin, and collagenase were evaluated 12 hours after the intraarticular injection of various doses of IL-1, and over a 24-hour period after injection at a single dose level. We used a monoclonal antibody (MAb) against leukocyte integrins, which markedly depressed leukocyte accumulation in SF, to evaluate the role of synovial leukocytes on IL-1-induced increases in SF proteoglycan and stromelysin levels.

RESULTS

Levels of both proteoglycans and stromelysin increased in the IL-1-injected joints between 4 hours and 24 hours after the injection of a single 200-ng dose of IL-1. The highest levels of stromelysin and proteoglycans were achieved with IL-1 doses greater than or equal to 100 ng. Infiltration of polymorphonuclear cells (PMN) into the joint fluid of the IL-1-injected rabbits also increased, in a dose-dependent manner. Treatment of rabbits with MAb 1B4 markedly reduced infiltration of PMN into the joint, without affecting either stromelysin or proteoglycan levels.

CONCLUSION

Taken together, the data suggest that there is a coordinate increase in SF stromelysin and proteoglycan levels in rabbits injected with IL-1, and that leukocytes play a minimal role in the accumulation of proteoglycans and stromelysin in the SF.

Value of a second freeze-thaw cycle in cryotherapy of common warts

A study of open, randomized, parallel-group design was performed to investigate the impact of a second freeze-thaw cycle on the cure rate, at 3 months, from cryotherapy of common warts on the hands and feet. Cryotherapy was performed at 3-week intervals, and subjects were randomized to receive either one or two freeze-thaw cycles. In addition, all subjects used keratolytic wart paints throughout the study, and plantar warts were pared prior to freezing. Three hundred subjects were recruited. At 3 months, 124 were cured, 83 were not cured, and 93 had defaulted. Among those who did not default the cure rate was 57% from the single freeze technique, and 62% from the double freeze technique, a difference of 5% (P = 0.53, 95% CI-8.1-18.6). Separate analyses for subjects with warts on the hands and on the feet demonstrated no effect of double freezing on hand warts. In contrast, for plantar warts, the cure rate was 41% from single freezing and 65% for double freezing, a difference of 24% (P = 0.04, 95% CI 2.9-44.4). The use of a double freeze-thaw cycle confers little or no advantage over a single freeze in the treatment of hand warts, but may be considerably more effective for plantar warts.