Transverse sinus stenting for idiopathic intracranial hypertension: a review of 52 patients and of model predictions

BACKGROUND AND PURPOSE

Transverse sinus stenosis is common in patients with IIH. While the role of transverse sinus stenosis in IIH pathogenesis remains controversial, modeling studies suggest that stent placement within a transverse sinus stenosis with a significant pressure gradient should decrease cerebral venous pressure, improve CSF resorption in the venous system, and thereby reduce intracranial (CSF) pressure, improving the symptoms of IIH and reducing papilledema. We aimed to determine if IIH could be reliably treated by stent placement in transverse sinus stenosis.

MATERIALS AND METHODS

We reviewed the clinical, venographic, and intracranial pressure data before and after stent placement in transverse sinus stenosis in 52 of our own patients with IIH unresponsive to maximum acceptable medical treatment, treated since 2001 and followed between 2 months and 9 years.

RESULTS

Before stent placement, the mean superior sagittal sinus pressure was 34 mm Hg (462 mm H(2)0) with a mean transverse sinus stenosis gradient of 20 mm Hg. The mean lumbar CSF pressure before stent placement was 322 mm H(2)O. In all 52 patients, stent placement immediately eliminated the TSS pressure gradient, rapidly improved IIH symptoms, and abolished papilledema. In 6 patients, symptom relapse (headache) was associated with increased venous pressure and recurrent stenosis adjacent to the previous stent. In these cases, placement of another stent again removed the transverse sinus stenosis pressure gradient and improved symptoms. Of the 52 patients, 49 have been cured of all IIH symptoms.

CONCLUSIONS

These findings indicate a role for transverse sinus stent placement in the management of selected patients with IIH.

Leptin gene expression in the brain and pituitary gland

The adipocyte-derived hormone, leptin, and its receptor, are now known to be integral components of a physiological signalling system that regulates fuel stores and energy balance. Constitutive leptin expression has been demonstrated only in adipose tissue, placenta and stomach. We have used RT-PCR to show that leptin mRNA is selectively transcribed in specific areas of rat brain and pituitary, and in a rat glioblastoma cell line. Using immunocytochemistry we have also shown leptin protein immunoreactivity in the corresponding tissues and cells, and confirmed this by Western blot using two epitope-specific antisera. Leptin mRNA expression in the hypothalamus is suppressed by fasting (48hr), suggesting a role for brain leptin in the central regulation of appetite. These data support the hypothesis that central nervous system derived leptin is a likely ligand for central leptin receptors.

Ethanol reduces bone formation and may cause osteoporosis

INTRODUCTION

The etiology of ethanol-associated osteopenia is not fully understood. In order to define the role of ethanol in the pathogenesis of hepatic osteodystrophy, we compared two groups of alcoholic patients with histologically established alcoholic liver disease.

PATIENTS AND METHODS

Twenty-eight patients currently drinking ethanol ("drinkers") and 12 claiming not to have consumed any ethanol for at least six months ("abstainers") were enrolled in the study. In addition, 35 non-alcoholic control subjects without clinical or biochemical evidence of liver disease were also studied. Bone mineral density and various biochemical and hormonal values were measured in each subject; iliac crest biopsies were taken under local anesthesia in the patients and under general anesthesia in the control subjects.

RESULTS

Forearm bone mineral densities, spinal bone mineral densities, and iliac crest cancellous bone areas were significantly lower in the alcoholic patients compared with control subjects (p less than 0.01 for all measurements), but these values did not differ between the drinkers and the abstainers. The drinkers, however, had significantly less osteoblastic activity than the abstainers, as assessed by dynamic bone histomorphometry (p less than 0.001). Serum bone Gla-protein concentrations were higher in the abstainers than in the drinkers (p less than 0.001). No differences were seen relating to histologic parameters of bone resorption, although the alcoholic patients who had lower serum free testosterone concentrations than the control subjects also had higher urinary hydroxyproline excretion rates.

CONCLUSION

These data suggest that ethanol may be responsible for osteoblastic dysfunction resulting in diminished bone formation and reduced bone mineralization.

Osteoporosis and skeletal fractures in chronic liver disease

In order to determine the prevalence and severity of hepatic osteodystrophy by non-invasive means we compared 115 consecutive ambulant patients with histologically proven chronic liver disease to 113 age and sex matched control subjects. Methods used included the assessment of fracture prevalence rates, spinal radiography, and measurements of bone mineral density in the spine and the forearm. Spinal and peripheral fractures were more prevalent in the patients than in the control subjects (p less than 0.03 and p less than 0.01 respectively). The type of the underlying liver disease did not significantly affect the fracture prevalence rates, but alcoholic patients sustained more peripheral fractures than patients with other hepatic disorders (p less than 0.05). The bone mineral densities of the spines and the forearms were significantly reduced in male patients of all age groups and in female patients aged 60 years or more (p less than 0.001 for men and p less than 0.01 for women for both measurements). The prevalence rates of spinal and forearm osteoporosis were twice as high among patients with liver disease than in control subjects regardless of the definitions used. The presence of cirrhosis and hypogonadism were major risk factors for development of both spinal (Beta coef = 0.190 and 0.176; SE = 0.079 and 0.086 respectively) and forearm osteoporosis (Beta coef = 0.20 and 0.29; SE = 0.073 and 0.80 respectively). Spinal bone density was the predominant determinant of spinal fractures (Beta coef = -0.007; SE = 0.001), while hypogonadism (Beta coef = 0.363; SE = 0.075) and cirrhosis (Beta coef = 0.185; SE = 0.068) were the major predictors of peripheral fractures. The concentrations of serum calcium and serum vitamin D metabolites and the use of corticosteroids were apparently without effect on the prevalence of skeletal fractures or bone density.

Majority-rule reduced consensus trees and their use in bootstrapping

Bootstrap analyses are usually summarized with majority-rule component consensus trees. This consensus method is based on replicated components and, like all component consensus methods, it is insensitive to other kinds of agreement between trees. Recently developed reduced consensus methods can be used to summarize much additional agreement on hypothesised phylogenetic relationships among multiple trees. The new methods are "strict" in the sense that they require agreement among all the trees being compared for any relationships to be represented in a consensus tree. Majority-rule reduced consensus methods are described and their use in bootstrap analyses is illustrated with a hypothetical and a real example. The new methods provide summaries of the bootstrap proportions of all n-taxon statements/partitions and facilitate the identification of hypotheses of relationships that are supported by high bootstrap proportions, in spite of a lack of support for particular components or clades. In practice majority-rule reduced consensus profiles may contain many trees. The size of the profile can be reduced by constraints on minimal bootstrap proportions and/or cardinality of the included trees. Majority-rule reduced consensus trees can also be selected a posteriori from the profile. Surrogates to the majority-rule reduced consensus methods using partition tables or tree pruning options provided by widely used phylogenetic inference software are also described. The methods are designed to produce more informative summaries of bootstrap analyses and thereby foster more informed assessment of the strengths and weaknesses of complex phylogenetic hypotheses.

In-situ atomic force microscopy study of beta-amyloid fibrillization

We report the use of atomic force microscopy to observe the initial stages of beta-amyloid fibrillization in situ. The growth of individual beta-amyloid protofibrils on a mica substrate was followed over several hours. The first in situ visualization of protofibril formation from single aggregate units of beta-amyloid is reported. The growth of these protofibrils through the subsequent addition of these aggregate units is also observed. Growth of the protofibrils is bi-directional and the outgrowth of protofibrils from a common amyloid/heterogeneous core is also observed. Elongation also occurred by the addition of protofibrils from solution. This data provides an exciting insight into the early stages of beta-amyloid fibrillization and can be used to enhance the understanding of the mechanism(s) by which beta-amyloid fibrillizes and may consequently enable inhibition of one or more stages of fibrillization as a potential therapeutic strategy.

Steroid-hormone receptors and survival after first relapse in breast cancer

Oestrogen receptors were measured in the primary breast tumours of 508 patients and progesterone receptors in those of 486 patients. Survival from mastectomy was significantly longer in patients with receptor-positive tumours. There was no significant difference between patients with receptor-positive and receptor-negative tumours in the relapse-free interval, but survival from first relapse was longer in patients with receptor-positive tumours. Axillary node status and tumour size indicated the probability of relapse but did not influence the length of survival after relapse. Response to tamoxifen or ovarian ablation was known in 65 of the 137 patients who relapsed. Survival from first relapse was significantly longer in patients who both responded to hormone therapy and had receptor-positive tumours. Patients who did not respond to hormone therapy and had receptor-positive tumours had the same survival characteristics as those with receptor-negative tumours who did not respond.

Retroviral diversity and distribution in vertebrates

We used the PCR to screen for the presence of endogenous retroviruses within the genomes of 18 vertebrate orders across eight classes, concentrating on reptilian, amphibian, and piscine hosts. Thirty novel retroviral sequences were isolated and characterized by sequencing approximately 1 kb of their encoded protease and reverse transcriptase genes. Isolation of novel viruses from so many disparate hosts suggests that retroviruses are likely to be ubiquitous within all but the most basal vertebrate classes and, furthermore, gives a good indication of the overall retroviral diversity within vertebrates. Phylogenetic analysis demonstrated that viruses clustering with (but not necessarily closely related to) the spumaviruses and murine leukemia viruses are widespread and abundant in vertebrate genomes. In contrast, we were unable to identify any viruses from hosts outside of mammals and birds which grouped with the other five currently recognized retroviral genera: the lentiviruses, human T-cell leukemia-related viruses, avian leukemia virus-related retroviruses, type D retroviruses, and mammalian type B retroviruses. There was also some indication that viruses isolated from individual vertebrate classes tended to cluster together in phylogenetic reconstructions. This implies that the horizontal transmission of at least some retroviruses, between some vertebrate classes, occurs relatively infrequently. It is likely that many of the retroviral sequences described here are distinct enough from those of previously characterized viruses to represent novel retroviral genera.

Multiple origins of anaerobic ciliates with hydrogenosomes within the radiation of aerobic ciliates

Some ciliates live anaerobically and lack mitochondria, but possess hydrogenosomes: organelles that contain hydrogenase and produce hydrogen. The origin of hydrogenosomes has been explained by two competing hypotheses: (i) they are biochemically modified mitochondria; or (ii) they are derived from endosymbiotic association(s) of ciliates and anaerobic eubacteria that possessed the hydrogenosome biochemistry. Phylogenetic analyses of representative aerobic, and anaerobic hydrogenosomal ciliates using host nuclear SSU rDNA sequences indicate a minimum of three, but more likely four, separate origins of hydrogenosomes. Whereas this does not refute either hypothesis, the implausibility of multiple convergent endosymbioses gives further support to the view that hydrogenosomes in ciliates derive from an existing organelle, which ultrastructural evidence suggests is the mitochondrion. Our results indicate a considerable potential for physiological-biochemical plasticity among a group of predominantly aerobic eucaryotes, and provide a phylogenetic framework to further refine and test hypotheses of the origins of the hydrogenosomal enzymes.

"Hospital at home" versus hospital care in patients with exacerbations of chronic obstructive pulmonary disease: prospective randomised controlled trial

OBJECTIVES

To compare "hospital at home" and hospital care as an inpatient in acute exacerbations of chronic obstructive pulmonary disease.

DESIGN

Prospective randomised controlled trial with three months' follow up.

SETTING

University teaching hospital offering secondary care service to 350 000 patients.

PATIENTS

Selected patients with an exacerbation of chronic obstructive pulmonary disease where hospital admission had been recommended after medical assessment.

INTERVENTIONS

Nurse administered home care was provided as an alternative to inpatient admission.

MAIN OUTCOME MEASURES

Readmission rates at two weeks and three months, changes in forced expiratory volume in one second (FEV(1)) from baseline at these times and mortality.

RESULTS

583 patients with chronic obstructive pulmonary disease referred for admission were assessed. 192 met the criteria for home care, and 42 refused to enter the trial. 100 were randomised to home care and 50 to hospital care. On admission, FEV(1) after use of a bronchodilator was 36.1% (95% confidence interval 2.4% to 69.8%) predicted in home care and 35.1% (6.3% to 63. 9%) predicted in hospital care. No significant difference was found in FEV(1 )after use of a bronchodilator at two weeks (42.6%, 3.4% to 81.8% versus 42.1%, 5.1% to 79.1%) or three months (41.5%, 8.2% to 74.8% versus 41.9%, 6.2% to 77.6%) between the groups. 37% of patients receiving home care and 34% receiving hospital care were readmitted at three months. No significant difference was found in mortality between the groups at three months (9% versus 8%).

CONCLUSIONS

Hospital at home care is a practical alternative to emergency admission in selected patients with exacerbations of chronic obstructive pulmonary disease.

Development of a robust flow cytometric assay for determining numbers of viable bacteria

Several fluorescent probes were evaluated as indicators of bacterial viability by flow cytometry. The probes monitor a number of biological factors that are altered during loss of viability. The factors include alterations in membrane permeability, monitored by using fluorogenic substrates and fluorescent intercalating dyes such as propidium iodide, and changes in membrane potential, monitored by using fluorescent cationic and anionic potential-sensitive probes. Of the fluorescent reagents examined, the fluorescent anionic membrane potential probe bis-(1,3-dibutylbarbituric acid)trimethine oxonol [DiBAC(inf4)(3)] proved the best candidate for use as a general robust viability marker and is a promising choice for use in high-throughput assays. With this probe, live and dead cells within a population can be identified and counted 10 min after sampling. There was a close correlation between viable counts determined by flow cytometry and by standard CFU assays for samples of untreated cells. The results indicate that flow cytometry is a sensitive analytical technique that can rapidly monitor physiological changes of individual microorganisms as a result of external perturbations. The membrane potential probe DiBAC(inf4)(3) provided a robust flow cytometric indicator for bacterial cell viability.

Migraine and menstruation: a pilot study

OBJECTIVE

To define the term "menstrual" migraine and to determine the prevalence of "menstrual" migraine in women attending the City of London Migraine Clinic.

DESIGN

Women attending the clinic were asked to keep a record of their migraine attacks and menstrual periods for at least 3 complete menstrual cycles.

RESULTS

Fifty-five women completed the study. "Menstrual" migraine was defined as "migraine attacks which occur regularly on or between days -2 to +3 of the menstrual cycle and at no other time". Using this criterion, 4 (7.2%) of the women in our population had "menstrual" migraine. All 4 women had migraine without aura. A further 19 (34.5%) had an increased number of attacks at the time of menstruation in addition to attacks at other times of the cycle. Eighteen (32.7%) had attacks occurring throughout the cycle but with no increase in number at the time of menstruation. Fourteen (25.5%) had no attacks within the defined period during the 3 cycles studied.

DISCUSSION

A small percentage of women have attacks only occurring at the time of menstruation, which can be defined as true "menstrual" migraine. This group is most likely to respond to hormonal treatment. The group of 34.5% who have an increased number of attacks at the time of menstruation in addition to attacks at other times of the month could be defined as having "menstrually related" migraine and might well respond to hormonal therapy. The 32.7% who have attacks throughout the menstrual cycle without an increase at menstruation are unlikely to respond to hormonal therapy. The 25.5% who do not have attacks related to menstruation almost certainly will not respond to hormonal therapy.

Intraoperative parathyroid hormone monitoring fails to detect double parathyroid adenomas: a 2-institution experience

BACKGROUND

We hypothesized that intraoperative parathyroid hormone monitoring (IOPTH) reliably would detect double parathyroid adenomas.

METHODS

This was a retrospective study of 20 patients undergoing conventional parathyroidectomy with resection of exactly 2 abnormal glands. Full exploration was performed regardless of IOPTH values, which were measured after anesthetic induction and 5 and 10 minutes following removal of the first abnormal parathyroid gland. Failure to fall below 50% of baseline value by 10 minutes following resection of the first gland indicated the presence of multiglandular disease.

RESULTS

All patients were cured. All excised glands were hypercellular on histology. Mean IOPTH values in 9 of the 20 patients with true negative results (noncurative decrease, another gland present) were 66% +/- 7% at 5 minutes and 83% +/- 15% at 10 minutes. The IOPTH values in 11 of the 20 patients with false positive results (curative decrease, another gland present) were 28% +/- 4% at 5 minutes and 18% +/- 2% at 10 minutes. The false positive rate of IOPTH was 55%.

CONCLUSIONS

We found that IOPTH failed to reliably detect the presence of double parathyroid adenomas. These data suggest that caution should be exercised when terminating limited parathyroid exploration based on a curative fall in IOPTH values.

Photopatch testing of 1155 patients: results of the U.K. multicentre photopatch study group

BACKGROUND

Photoallergic contact dermatitis can be difficult to diagnose if not appropriately investigated. Currently, the most common U.K. photoallergens appear to be sunscreen chemicals. The investigation of choice is photopatch testing (PPT), which is probably underused. In part, this is due to differences in methodology and results interpretation.

OBJECTIVES

To conduct PPT using a group of sunscreen chemicals, defined indications and a standardized methodology including interpretation and relevance of reactions in patients attending for investigation at 17 centres across the U.K., Ireland and the Netherlands.

METHODS

Patients (n = 1155) who fulfilled the inclusion criteria were investigated with PPT using sunscreen chemicals in addition to suspected topical products. Readings were taken at 24, 48 and 72 h following standardized ultraviolet A irradiation (5 J cm(-2)). The clinical relevance of any reaction was recorded.

RESULTS

Of the 1155, 130 had allergic reactions (11.3%). Of these, 51 had photoallergy (PA) (4.4%), 64 had contact allergy (CA) (5.5%), and 15 patients had combined PA and CA (1.3%). Multiple PA was seen in some. The most common photoallergen was benzophenone-3 (27 reactions; 21%). Most reactions (60%) were clinically relevant. The most common indication for testing in patients found to have PA was a history of reacting to a sunscreen (41%). The other 59% had an exposed-site dermatitis/skin problem or a photodermatosis. Some centres (n = 8) performed readings after the standard 48-h reading, and an extra 32 PA and 22 CA reactions were detected, which were not evident at 48 h. A new photoallergen (octyl triazone) was detected in two patients.

CONCLUSIONS

Sunscreen PA and CA are probably equally uncommon. Most reactions, of both reaction types, were relevant clinically. A large proportion of patients (59%) found to have PA was unaware of reacting to a sunscreen chemical, suggesting that PA should be considered as an explanation in any exposed-site dermatitis. Although this study focused on reactions at 48 h postirradiation, readings performed up to 96 h, while inconvenient, add value by detecting additional relevant responses. A previously unknown photoallergen was found, highlighting the need for awareness of novel photoallergens in the marketplace. A standardized PPT method not only encourages more use of this investigation, but also facilitates comparison of results between centres and so will improve our understanding of PA.

Observation of J/ψp Resonances Consistent with Pentaquark States in Λ_{b}^{0}→J/ψK^{-}p Decays

Observations of exotic structures in the J/ψp channel, which we refer to as charmonium-pentaquark states, in Λ_{b}^{0}→J/ψK^{-}p decays are presented. The data sample corresponds to an integrated luminosity of 3 fb^{-1} acquired with the LHCb detector from 7 and 8 TeV pp collisions. An amplitude analysis of the three-body final state reproduces the two-body mass and angular distributions. To obtain a satisfactory fit of the structures seen in the J/ψp mass spectrum, it is necessary to include two Breit-Wigner amplitudes that each describe a resonant state. The significance of each of these resonances is more than 9 standard deviations. One has a mass of 4380±8±29 MeV and a width of 205±18±86 MeV, while the second is narrower, with a mass of 4449.8±1.7±2.5 MeV and a width of 39±5±19 MeV. The preferred J^{P} assignments are of opposite parity, with one state having spin 3/2 and the other 5/2.

The prognostic significance of two epithelial membrane antigens expressed by human mammary carcinomas

As many patients with mammary carcinoma are now treated by conservative forms of surgery, there is a need for prognostic information obtainable from the primary tumour alone. One possible source is the antigenic profile of tumour cells. Using an indirect immunoperoxidase technique, we stained histological sections of the primary tumour from 175 patients with each of two monoclonal antibodies (HMFG-1, HMFG-2), raised against milk fat globule membrane antigens known to be preserved in formalin-fixed tissues. Sections were assessed by light microscopy as to both the overall distribution of antigen expressed and its site in tumour cells. The findings were related to relapse-free survival by life-table analysis. The median duration of follow-up was 36 months. Two patterns of staining with antibody HMFG-1 gave information of prognostic significance but staining with HMFG-2 was without significance. Complete absence of staining with HMFG-1 in 13 patients was associated with an extremely poor prognosis and 10 (77%) of these patients developed metastases within 18 months of follow-up (p less than 0.001). Extracellular staining (ECS) in 22 patients, however, was associated with a favourable prognosis. As assessed by a semi-quantitative method, only one patient (5%) demonstrating a high level of ECS developed metastases (p less than 0,004). These two patterns were analysed for a relationship to other prognostic indicators. Absence of staining was independent of histological grade, tumour size, axillary lymph node status and menopausal status. ECS was associated with low histological grade although this relationship was not absolute. In addition to their use in diagnosis, we conclude that monoclonal antibodies such as HMFG-1 may be useful as prognostic indicators.

KiSS-1 mRNA in adipose tissue is regulated by sex hormones and food intake

Hypothalamic KiSS-1 gene expression is critical for the maintenance of reproductive function, and levels are attenuated by sex hormones and by food restriction, providing a link between fat mass and fertility. We hypothesized that adipose tissue (FAT) would express KiSS-1. KiSS-1 mRNA was quantified in FAT, hypothalamus (HYP) and pituitary gland (PIT) using realtime RT-PCR. FAT KiSS-1 expression was sensitive to sex steroids and to nutritional status. Gonadectomized rats given estradiol (E; females) or testosterone (T; males) revealed striking increases in KiSS-1 mRNA in FAT (E: 8-fold, p<0.01; T: 5-fold, p<0.01). In contrast, HYP KiSS-1 expression was reduced by E/T, whereas PIT expression was reduced by gonadectomy only in females, reversed by E. Food restriction (18 h) increased FAT KiSS-1 mRNA in both sexes (2.5-4.0-fold, p<0.01), but decreased levels in male PIT and female HYP. Conversely, FAT expression was reduced in rats fed a high fat diet (HFD), as well as in obese Zucker rats, whereas PIT expression was increased in Zucker rats (p<0.05) but not by HFD. In contrast HYP KiSS-1 mRNA was elevated by HFD. Experiments in which the arcuate nucleus was damaged by an excitotoxic lesion revealed that hypothalamic KiSS-1 mRNA was significantly reduced, whereas FAT levels were unaffected, suggesting that regulation of KiSS-1 in FAT is independent of the hypothalamus. In conclusion, KiSS-1 expression is differentially regulated by sex hormones, food intake and obesity in FAT, HYP and PIT. Kisspeptins of adipose tissue origin may act as adipokines or as local regulators of adipocyte function.

Skeletal changes in preterm infants

The skeletal changes in 19 very low birthweight infants (less than 1500 g) were observed from birth to 10 weeks, by means of clinical, biochemical, and radiological techniques. All infants were receiving a supplement of 800 IU vitamin D a day from age 2 weeks. None of the infants showed any specific physical sign of rickets during the period of study. Six infants showed radiological evidence of skeletal demineralisation; 1 of these had severe changes of rickets and 1 had both rickets and fractures. These 6 infants were of shorter gestational periods and lower birthweights than the infants not showing radiological changes. They tended to have more clinical problems and to reach a predetermined volume of feeds (160 ml/kg a day) later than the unaffected infants. Serum alkaline phosphatase values were significantly higher at 5 weeks in the infants with abnormal radiographs than in those without. There were no significant differences between the two groups in relation to serum calcium, inorganic phosphate, 25 hydroxyvitamin D, and immunoreactive parathyroid hormone. The pathogenesis of the skeletal lesions of very low birthweight infants remains unknown.

Opiatergic control of LH secretion is eliminated by gonadectomy

We have studied the stimulatory effects of naloxone and the inhibitory influence of the opiate peptide, FK 33-824, on LH secretion in the gonadectomized rat. Our results indicate that endogenous and exogenous opiate involvement in LH release disappear coincident with the removal of gonadal steroid feedback. At 7 days post-surgery naloxone is no longer able to stimulate LH secretion in male or female rats. Similarly, by 7 days in the male, and 21 days in the female, FK 33-824 is unable to inhibit LH secretion. We conclude that the coupling of hypothalamic opiate receptors to the LH regulatory mechanisms is dependent upon gonadal steroids. The most important of these appear to be estradiol and testosterone, since careful priming of long-term gonadectomized rats with these steroids is able to largely restore the LH responses to naloxone and FK 33-824.