Effects of early human immunodeficiency virus infection on cerebral white matter blood flow autoregulation

Blood flow autoregulation in cerebral white matter was measured before and after acute nicardipine-induced changes in mean arterial pressure of 10-21% in 21 treatment naïve HIV-positive adults and 32 controls. The autoregulatory index (-% cerebral blood flow change/% mean arterial pressure change) was not different at baseline ( P  = 0.71) or after 1 year of treatment ( n  = 11, P  = 0.17). We found no autoregulatory defect to explain the increased stroke risk or the development of cerebral white damage in people with HIV.

Reduction in cerebral oxygen metabolism in subcortical regions may be a biomarker of cognitive decline in people living with human immunodeficiency virus

BACKGROUND AND PURPOSE

Regional cerebral blood flow (rCBF) and oxygen metabolism (rCMRO₂ ) in whole brain, white matter, gray matter and lenticular nuclei were studied in people living with human immunodeficiency virus (PLHIV) as well as HIV-associated neurocognitive disorder (HAND).

METHODS

Treatment-naïve PLHIV underwent neurocognitive assessment and magnetic resonance (MR) measurement of rCBF and rCMRO₂ with repeat after 12 months of antiretroviral therapy (ART). Age- and sex-matched controls underwent single MR measurements. Regional CBF and rCMRO₂ were compared amongst symptomatic, asymptomatic, normal HAND and controls using analysis of variance. Longitudinal analysis of HAND worsening (≥1 category) was assessed after 12 months of ART and correlated with rCBF and rCMRO₂ measured by MR imaging using the paired-sample t test.

RESULTS

Thirty PLHIV completed baseline and 12-month assessments (29 with rCMRO₂ measurement). At baseline HAND assessment, 13% had no cognitive impairment, 27% had asymptomatic neurocognitive impairment, 60% had mild neurocognitive disorder and none had HIV-associated dementia. At 12 months, 13% had no cognitive impairment, 20% had asymptomatic neurocognitive impairment, 50% had mild neurocognitive disorder and 17% had HIV-associated dementia. In those without HAND worsening (N = 21) rCMRO₂ remained stable and in those with HAND worsening (N = 8) rCMRO₂ measurement declined from baseline to 12 months in white matter (2.05 ± 0.40 to 1.73 ± 0.51, p = 0.03) and lenticular nuclei (4.32 ± 0.39 to 4.00 ± 0.51, p = 0.05).

CONCLUSIONS

In recently diagnosed PLHIV, no association was found between rCBF or rCMRO₂ and cognitive impairment at baseline. There was a reduction in rCMRO₂ in those with worsening of cognitive function at 12 months on ART. Reduction in rCMRO₂ may be a biomarker of cognitive decline in PLHIV.

A longitudinal study of olfactory dysfunction and parosmia in mild COVID-19 cases

Background

COVID-19-related olfactory dysfunction (OD) can persist long after patients recover from acute infection, yet few studies have investigated the long-term progression of this complication. Moreover, existing studies are focused on hyposmia/anosmia but parosmia is becoming an increasingly recognized long-term symptom.

Methods

We completed a longitudinal study about OD in individuals with mild cases of COVID-19. Participants completed a questionnaire and Brief Smell Identification Test (BSIT) one week, one month and one year after diagnosis. At one-year, participants completed an additional survey about parosmia.

Results

We obtained questionnaires and psychophysical olfactory testing information from participants at one week (n=45), one month (n=38), and one year (n=33) post COVID-19 diagnosis. At one-year, 15.2% of participants had persistent OD and 66.7% of participants reported experiencing parosmia at some point following COVID-19 diagnosis. The mean onset of parosmia was 1.3 weeks (SD: 1.9 weeks) after diagnosis, although two patients reported delayed onset (>4 weeks after diagnosis). Eight patients (24.2%) reported ongoing parosmia one year after diagnosis. Of the patients whose parosmia resolved, the mean duration of symptoms was 7.2 weeks (SD: 7.3 weeks).

Conclusion

Decreased sense of smell associated with COVID-19 infection has received significant recognition in both the media and in the medical literature. Symptoms of OD and parosmia were common in our patients with COVID-19. Hyposmia, anosmia, and parosmia, all decrease quality of life, necessitating continued research to understand the pathogenesis, course of symptoms, and possible treatment for these complications.

Autoregulation of White Matter Cerebral Blood Flow to Arterial Pressure Changes in Normal Subjects

Endothelial dysfunction causing impaired cerebrovascular vasodilatory capacity in response to reduced blood pressure has been proposed as a mechanism of white matter (WM) disease development. This study investigated autoregulation of CBF to blood pressure reduction in WM and gray matter (GM) in normal subjects recruited as controls for a study of cerebrovascular function in human immunodeficiency virus positive subjects. They underwent baseline CBF and oxygen extraction fraction measurement by MRI before and after mean arterial pressure (MAP) reduction. Autoregulatory Index (AI) was computed as CBF AI = -%CBF change/% MAP change. Thirty of 44 subjects achieved target MAP reduction. MAP was reduced -13.65 ± 2.35 (range 10 to 20) %. WM AI of -0.61 ± 1.23 was significantly more negative than GM AI of 0.02 ± 0.44 (paired t test, p= 0.016). WM CBF fell (paired Wilcoxon, p= 0.03) whereas GM CBF did not change (paired Wilcoxon, p=0.92). WM AI was different from 0 (p=0.011, one-sample t-test vs 0), whereas GM AI was not (p=0.913, one-sample t-test vs 0). These data demonstrate that maintenance of CBF to 10-20% reductions in MAP is less effective in WM than in GM. This may put WM at higher risk for ischemic damage.

COVID-19 related olfactory dysfunction prevalence and natural history in ambulatory patients

Background

Evidence regarding prevalence of COVID-19 related Olfactory dysfunction (OD) among ambulatory patients is highly variable due to heterogeneity in study population and measurement methods. Relatively few studies have longitudinally investigated OD in ambulatory patients with objective methods.

Methods

We performed a longitudinal study to investigate OD among COVID-19 ambulatory patients compared to symptomatic controls who test negative. Out of 81 patients enrolled, 45 COVID-19 positive patients and an age- and sex-matched symptomatic control group completed the BSIT and a questionnaire about smell, taste and nasal symptoms. These were repeated at 1 month for all COVID-19 positive patients, and again at 3 months for those who exhibited persistent OD. Analysis was performed by mixed-effects linear and logistic regression.

Results

46.7% of COVID-19 patients compared to 3.8% of symptomatic controls exhibited OD at 1-week post diagnosis (p<0.001). At 1 month, 16.7%, (6 of 36), of COVID-19 patients had persistent OD. Mean improvement in BSIT score in COVID-19 patients between 1-week BSIT and 1 month follow-up was 2.0 (95% CI 1.00 - 3.00, p<0.001). OD did not correlate with nasal congestion (r= -0.25, 95% CI, -0.52 to 0.06, p=0.12).

Conclusions

Ambulatory COVID-19 patients exhibited OD significantly more frequently than symptomatic controls. Most patients regained normal olfaction by 1 month. The BSIT is a simple validated and objective test to investigate the prevalence of OD in ambulatory patients. OD did not correlate with nasal congestion which suggests a congestion-independent mechanism of OD.

Reduced homeobox protein MSX1 in human endometrial tissue is linked to infertility

STUDY QUESTION

Is protein expression of the muscle segment homeobox gene family member MSX1 altered in the human secretory endometrium by cell type, developmental stage or fertility?

SUMMARY ANSWER

MSX1 protein levels, normally elevated in the secretory phase endometrium, were significantly reduced in endometrial biopsies obtained from women of infertile couples.

WHAT IS KNOWN ALREADY

Molecular changes in the endometrium are important for fertility in both animals and humans. Msx1 is expressed in the preimplantation mouse uterus and regulates uterine receptivity for implantation. The MSX protein persists a short time, after its message has been down-regulated. Microarray analysis of the human endometrium reveals a similar pattern of MSX1 mRNA expression that peaks before the receptive period, with depressed expression at implantation. Targeted deletion of uterine Msx1 and Msx2 in mice prevents the loss of epithelial cell polarity during implantation and causes infertility.

STUDY DESIGN, SIZE DURATION

MSX1 mRNA and cell type-specific levels of MSX1 protein were quantified from two retrospective cohorts during the human endometrial cycle. MSX1 protein expression patterns were compared between fertile and infertile couples. Selected samples were dual-labeled by immunofluorescence microscopy to localize E-cadherin and β-catenin in epithelial cells.

PARTICIPANTS/MATERIALS, SETTING METHODS

MSX1 mRNA was quantified by PCR in endometrium from hysterectomies (n = 14) determined by endometrial dating to be in the late-proliferative (cycle days 10-13), early-secretory (cycle days 14-19) or mid-secretory (cycle days 20-24) phase. MSX1 protein was localized using high-throughput, semi-quantitative immunohistochemistry with sectioned endometrial biopsy tissues from fertile (n = 89) and infertile (n = 89) couples. Image analysis measured stain intensity specifically within the luminal epithelium, glands and stroma during the early-, mid- and late- (cycle days 25-28) secretory phases.

MAIN RESULTS AND THE ROLE OF CHANCE

MSX1 transcript increased 5-fold (P < 0.05) between the late-proliferative and early secretory phase and was then down-regulated (P < 0.05) prior to receptivity for implantation. In fertile patients, MSX1 protein displayed strong nuclear localization in the luminal epithelium and glands, while it was weakly expressed in nuclei of the stroma. MSX1 protein levels accumulated throughout the secretory phase in all endometrial cellular compartments. MSX1 protein decreased (P < 0.05) in the glands between mid- and late-secretory phases. However, infertile patients demonstrated a broad reduction (P < 0.001) of MSX1 accumulation in all cell types throughout the secretory phase that was most pronounced (∼3-fold) in stroma and glands. Infertility was associated with persistent co-localization of E-cadherin and β-catenin in epithelial cell junctions in the mid- and late-secretory phases.

LIMITATIONS, REASONS FOR CAUTION

Details of the infertility diagnoses and other patient demographic data were not available. Therefore, patients with uterine abnormalities (Mullerian) could not be distinguished from other sources of infertility. Antibody against human MSX2 is not available, limiting the study to MSX1. However, both RNAs in the human endometrium are similarly regulated. In mice, Msx1 and Msx2 are imperative for murine embryo implantation, with Msx2 compensating for genetic ablation of Msx1 through its up-regulation in a knockout model.

WIDER IMPLICATIONS OF THE FINDINGS

This investigation establishes that the MSX1 homeobox protein accumulation is associated with the secretory phase in endometrium of fertile couples, and is widely disrupted in infertile patients. It is the first study to examine MSX1 protein localization in the human endometrium, and supported by genetic findings in mice, suggests that genes regulated by MSX1 are linked to the loss of epithelial cell polarity required for uterine receptivity during implantation.

STUDY FUNDING/COMPETING INTERESTS

This research was supported by the NICHD National Cooperative Reproductive Medicine Network grant HD039005 (M.P.D.), NIH grants HD068524 (S.K.D.), HD071408 (D.R.A., M.P.D.), and HL128628 (S.D.), the Intramural Research Program of the NICHD, March of Dimes (S.K.D., S.D.) and JSPS KAKENHI grant 26112506 (Y.H.). There were no conflicts or competing interests.

A Comprehensive Analysis of Replicative Lifespan in 4,698 Single-Gene Deletion Strains Uncovers Conserved Mechanisms of Aging

Many genes that affect replicative lifespan (RLS) in the budding yeast Saccharomyces cerevisiae also affect aging in other organisms such as C. elegans and M. musculus. We performed a systematic analysis of yeast RLS in a set of 4,698 viable single-gene deletion strains. Multiple functional gene clusters were identified, and full genome-to-genome comparison demonstrated a significant conservation in longevity pathways between yeast and C. elegans. Among the mechanisms of aging identified, deletion of tRNA exporter LOS1 robustly extended lifespan. Dietary restriction (DR) and inhibition of mechanistic Target of Rapamycin (mTOR) exclude Los1 from the nucleus in a Rad53-dependent manner. Moreover, lifespan extension from deletion of LOS1 is nonadditive with DR or mTOR inhibition, and results in Gcn4 transcription factor activation. Thus, the DNA damage response and mTOR converge on Los1-mediated nuclear tRNA export to regulate Gcn4 activity and aging.

Abstract W P399: Magnetic Resonance Imaging Based Cerebral Blood Flow Changes in Asymptomatic Human Immunodeficiency Virus Infected Subjects

Background: Human Immunodeficiency Virus (HIV) infected individuals are at high risk for ischemic stroke. Magnetic resonance imaging (MRI) method of measurement of cerebral blood flow (CBF) and oxygen extraction fraction (OEF) may help assess the stroke risk in asymptomatic HIV subjects.

Objectives: To evaluate MR measured CBF and OEF in treatment naïve asymptomatic HIV+ subjects and HIV- controls.

Methods: Treatment naïve asymptomatic HIV+ subjects and age-gender-race matched HIV- controls were assessed for CBF using a pulsed arterial spin labeling (PASL) approach and Oxygen Extraction Fraction (OEF) using MRI T2*-weighted echo-planar imaging (EPI) sequences. All images were acquired using a Siemens 3T MR scanner (Treo, Siemens Medical Systems Inc). Quantitative CBF and OEF measurements were made in the whole-brain, gray matter and white matter and compared between the groups using unpaired t-test.

Results: A total of 65 subjects of who, 35 treatment naïve HIV+ subjects (Mean age ± SD=30±7,89% male, 31% white, 49% black and 20% others) and 30 age-gender-race matched HIV- controls (Mean age± SD= 31±8,93% male, 37% white, 53% black and 10% others) consented to the protocol. HIV+ subjects compared to HIV- controls had significantly higher whole brain CBF (58.0 ± 13.8 ml/100g/min vs. 51.3 ± 9.0 ml/100g/min; p=0.03) and gray matter CBF (72.9 ± 16.2 ml/100g/min vs. 63.9 ± 9.9 ml/100g/min; p=0.01). However, values for whole brain OEF (0.4 ± 0.04) and gray matter OEF (0.4 ± 0.05) were similar for both groups. White matter CBF in HIV+ subjects (41.5 ± 13.1 ml/100g/min) compared to HIV- controls (37.2 ± 9.2 ml/100g/min) was not significantly higher (p=0.16) while white matter OEF (0.4 ± 0.04 HIV+ subjects vs. 0.4 ± 0.03 HIV-controls) showed no changes.

Conclusions: The observed increase of whole brain CBF in treatment naïve HIV + subjects compared to HIV- matched controls, without corresponding changes in the OEF appears to be driven by a pronounced significant change in the gray matter compared with the white matter. These changes in CBF without corresponding changes in OEF suggest increase in metabolic activity, and may explain the higher stroke risk in asymptomatic HIV subjects.

Abstract WP227: Magnetic Resonance Measurement Of Static Global And Regional Cerebral Autoregulation

Background: Reliable methods used to test static cerebral autoregulation are time-consuming and/or invasive.

Objectives: To evaluate if noninvasive magnetic resonance measured oxygen extraction fraction (OEF), cerebral blood flow (CBF), and oxygen metabolic index (OMI=CBF×OEF) can consistently detect expected physiological changes in humans under normal and 10-15% lowered mean arterial pressure (MAP).

Methods: Static cerebral autoregulation was determined by measuring changes in CBF using a pseudo continuous arterial spin labeling (pCASL) approach and Oxygen Extraction Fraction (OEF) using MRI T2‘-weighted asymmetric spin echo echo-planar imaging (EPI) sequences, in response to 10-15% reductions in MAP in stroke-free controls induced by using IV Nicardipine. Images were acquired in 3T MR scanner (Trio, Siemens Medical Systems Inc). Autoregulation was measured globally and regionally in the anterior (ACA), the middle (MCA) and the posterior cerebral artery (PCA) territories of the brain manually defined using autopsy based model. Autoregulatory Index (AI) was computed (AI = %CBF change/% MAP change) supplemented by CBF associated OEF changes. Baseline regional CBF and OEF, AI, CBF and OEF changes to 10-15% lowering of MAP

Results: Nineteen normal volunteers (mean age 30, 95% male, 50% white, 40% black, 10% others) were consented to the protocol approved by the institutional review board. MAP lowering was successfully achieved in all subjects (Mean ± standard deviation of MAP lowering of 12.5 ± 5.6 mm Hg). At a global level this resulted in no significant change between pre-MAP lowering CBF (56.0 ± 8.5 ml/100g/min) and post-MAP lowering CBF (55.9± 8.8 ml/100g/min). This translated to a AI of 0 ± 1.2. The CBF results corroborated with no significant change in OEF and OMI. Baseline regional CBF was higher in the MCA territory (66.1 ± 7.6 ml/100g/min) compared with the ACA territory (52.8 ± 8.6ml/100g/min, p<0.001). The AIs were consistent (ANOVA p=0.15) at regional levels across ACA (-1.5 ± 3.1), MCA(-0.3± 2.1) and PCA (-0.1 ± 1.4) territories.

Conclusions: Global and regional static cerebral autoregulation can be measured using MR measurement of CBF, OEF and OMI, before and after 10-15% reductions in MAP in healthy volunteers.

A focus group study of predictors of relapse in electronic gaming machine problem gambling, part 2: factors that 'pull' the gambler away from relapse

This study aimed to develop an empirically based description of relapse in Electronic Gaming Machine (EGM) problem gambling (PG) by describing the processes and factors that 'pull' the problem gambler away from relapse contrasted with the 'push' towards relapse. These conceptualisations describe two opposing, interacting emotional processes occurring within the problem gambler during any relapse episode. Each relapse episode comprises a complex set of psychological and social behaviours where many factors interact sequentially and simultaneously within the problem gambler to produce a series of mental and behaviour events that end (1) with relapse where 'push' overcomes 'pull' or (2) continued abstinence where 'pull' overcomes 'push'. Four focus groups comprising thirty participants who were EGM problem gamblers, gamblers' significant others, therapists and counsellors described their experiences and understanding of relapse. The groups were recorded, recordings were then transcribed and analysed using thematic textual analysis. It was established that vigilance, motivation to commit to change, positive social support, cognitive strategies such as remembering past gambling harms or distraction techniques to avoid thinking about gambling to enable gamblers to manage the urge to gamble and urge extinction were key factors that protected against relapse. Three complementary theories emerged from the analysis. Firstly, a process of reappraisal of personal gambling behaviour pulls the gambler away from relapse. This results in a commitment to change that develops over time and affects but is independent of each episode of relapse. Secondly, relapse may be halted by interacting factors that 'pull' the problem gambler away from the sequence of mental and behavioural events, which follow the triggering of the urge and cognitions to gamble. Thirdly, urge extinction and apparent 'cure' is possible for EGM gambling. This study provides a qualitative, empirical model for understanding protective factors against gambling relapse.

Transvaginal strangulated small intestinal hernia after abdominal sacrocolpopexy: case report and literature review

PURPOSE

To report a case of transvaginal small intestinal hernia following abdominal sacrocolpopexy and review this clinical presentation in the current literature.

METHODS

A review of our case and a literature review of vaginal evisceration were carried out.

RESULTS

The patient underwent sacrocolpopexy and a Burch procedure. Six months later, a recurrent enterocele through a 1 cm defect in the vaginal vault was diagnosed. Several weeks later she presented with an incarcerated and strangulated loop of small intestine extending beyond the introitus. This required an urgent exploratory laparotomy, ileocecal resection, and vaginal vault closure. Postoperatively, she experienced gradual prolapse recurrence and is currently successfully managed with a pessary. Risk factors that include vaginal atrophy, chronic constipation, and previous pelvic surgery may have contributed to the evisceration, mesh erosion, and may have caused the breakdown in the vaginal vault mucosa ultimately responsible for the evisceration. In addition, placement of the sacrocolpopexy mesh without tension, and utilization of an interposition graft to reinforce the weakened vaginal vault tissue, are aspects of the surgical procedure that may influence outcomes. At the time of evisceration repair, the best approach to resuspend the vaginal vault, and prevent recurrent prolapse or evisceration, is currently unknown.

CONCLUSION

Vaginal evisceration is a potential complication of abdominal sacrocolpopexy. Early recognition and treatment of this complication is critical, and prolapse recurrence may occur even after surgical repair.

The first description of the palmaris brevis muscle

Giovanni Battista Canano was born in Italy in 1515 and his work has gone mostly unknown. Very few copies of this anatomist and physician's book are known to exist. Interestingly, Canano reported and depicted what we believe, to be the first description of the palmaris brevis muscle. This description would be some 200 years prior to what is thought to be the earliest mention of this muscle by William Cheselden in his book, The Anatomy of the Human Body, published in 1713.

Flesh quality of market-size farmed and wild British Columbia salmon

This study compared the flesh quality of farmed and wild sources of British Columbia (BC) salmon with respect to concentrations of polychlorinated biphenyl compounds, polychlorinated dibenzodioxins/dibenzofurans and their associated toxic equivalents, total mercury (THg), methylmercury (MeHg), and selected fatty acids of known importance for human health viz., omega-3 (n-3) highly unsaturated fatty acids (n-3 HUFAs) and (n-6) fatty acids. Skinned fillets from known sources of farmed Atlantic, coho, and chinook salmon (n = 110) and wild coho, chinook, chum, sockeye, and pink salmon (n = 91) were examined. Atlantic salmon contained higher PCB concentrations (means, 28-38 ng/g) than farmed coho or chinook salmon, and levels in these latter species were similar to those in wild counterparts (means, 2.8-13.7 ng/g). PCB levels in Atlantic salmon flesh were, nevertheless, 53-71-fold less than the level of concern for human consumption of fish, i.e., 2000 ng/g as established by Health Canada and the U.S. Food and Drug Administration (US-FDA). Similarly, THg and MeHg levels in all samples were well below the Health Canada guideline (0.5 microg/g) and the US-FDA action level (1.0 microg/g). On average, THg in farmed salmon (0.021 microg/g) was similar to or lower than wild salmon (0.013-0.077 microg/g). Atlantic salmon were a richer source (mean, 2.34 g/100 g fillet) of n-3 HUFAs than the other farmed and wild sources of salmon examined (means, 0.39-1.17 g/100 g). The present findings support the recommended weekly consumption guidelines for oily fish species (includes all BC salmon sources) for cardio-protective benefits as made by the American Heart Association and the UK Food Standards Agency.

Diastereoselectivity in scalemic tartrate/titanium epoxidations

Nonlinearity in the diastereoselectivity of epoxidation of allylic alcohols with mixtures of titanium isopropoxide, tertbutyl hydroperoxide, and diethyl tartrate was observed. Racemic and enantiomerically pure alcohols E-2-methyl-4-hexen-3-ol and E-1-methoxy-5-(O-tertbutyldimethylsilyloxy)-2-penten-4-ol were prepared. Epoxidation reactions were carried out with Ti(OPri)4 and ButOOH accompanied by diethyl tartrate of varying enantiomeric purity. The simplest explanation of these results is that a dimeric epoxidation reagent is involved, with significantly different reactivity for the homochiral and racemic forms.

Two cases of cerebral aneurysms in HIV+ children

Two cases of fusiform cerebral aneurysms in human immunodeficiency virus (HIV) positive children are presented. To our knowledge, only 9 patients with this association have been reported. One of our patients represents the first report of a patient with an aneurysm associated with varicella-zoster vasculitis. One patient presented with a subarachnoid hemorrhage, Hunt-Hess grade IV, and posed difficult surgical management. The other patient suffered a cerebral infarct with a resulting hemiparesis. The first patient had a ventriculostomy placed, initially improved, and subsequently died from rebleeding. The second patient improved with medical management. AIDS arteriopathy, and specifically fusiform aneurysms, are being increasingly reported. The various presentations of this surgically challenging entity in light of other AIDS-related syndromes pose difficult management decisions. On occasion, the intracranial aneurysm may be the initial form of presentation as was present in our first patient.

Differential expression of Xenopus ribosomal protein gene XlrpS1c

Components of the translational machinery of the cell, including ribosomal proteins, are generally considered to be clear examples of housekeeping genes with a spatially ubiquitous distribution of messenger RNA during embryonic development. Here we present data based upon in situ hybridization experiments as well as RNase protection assays, demonstrating that Xenopus ribosomal protein gene S1 is differentially expressed in a complex and spatially distinct pattern during embryogenesis. We observed dramatically high levels of expression in some tissues, such as the branchial arches, otic vesicles, optic vesicles and somites and virtually no expression in other tissues, such as the cement gland, epidermis and notochord. Moreover, ribosomal protein genes S22, L1, and L5 display expression patterns nearly identical to S1. Our data is consistent with a model of ribosomal gene expression according to which ribosomal protein genes (or perhaps a subset of ribosomal protein genes) may be expressed at low levels in all tissues, but are abundantly expressed in other cell types reflecting a dynamic and complex pattern of transcriptional control throughout embryonic development.

Closure of myelomeningocele using skin from stillborn twin

We report a case of homologous skin transplantation from a stillborn twin to the surviving twin for coverage of a myelomeningocele defect. Genetic studies were not available preoperatively, however, similar morphogenetic anomalies of the twins suggested monozygosity. Long-term follow-up revealed a well-healed graft. Cutaneous genetics and literature review of twin homologous skin transplantation are presented.

Emotional support can precipitate recovery. Setting up a counselling service for breast cancer patients

Many women who are diagnosed with breast cancer do not receive the counselling and support they require. Nurse counsellors are well-equipped to take on this responsibility, and can help women consider their treatment options.

Exophytic syrinx, an extreme form of syringomyelia: CT, myelographic, and MR imaging features

Magnetic resonance (MR) imaging and computed tomography (CT) were used to study severe syringomyelia, in which the syrinx was so eccentric relative to the center of the spinal cord that at initial examination it appeared to be an exophytic extramedullary mass, in five of six patients with type 2 Arnold-Chiari malformation and one patient with an intramedullary tumor. Sagittal and axial images were routinely obtained at 1.5 T; CT was performed after intrathecal injection of contrast material. On sagittal MR images, the exophytic component of the syrinx typically displaced the spinal cord peripherally and mimicked an extramedullary intradural lesion such as an arachnoid cyst or meningioma. On axial MR images, the gradual appearance and disappearance of this component could be traced as it compressed the spinal cord, which had a signet-ring appearance at the equator of the syrinx. It is concluded that both MR imaging and postmyelographic CT can reveal the characteristics of this lesion on axial images, but MR imaging is superior because it enables direct sagittal imaging.

Sex hormone changes in chronic liver disease: a matched study of alcoholic versus non-alcoholic liver disease

Men with liver disease are hypogonadal and feminized. European workers consider the liver disease itself to be the major factor but American workers blame alcohol consumption. We studied sexual dysfunction and sex hormones in three matched groups of men; controls (n = 22), those with alcoholic liver disease (n = 21), and those with non-alcoholic liver disease (n = 21). Men with alcoholic liver disease had more sexual dysfunction. Testosterone and androstenedione concentrations were lower and oestradiol and dehydroepiandrosterone sulphate levels were raised in the liver disease groups. The changes were greatest in the alcoholic liver disease group. In this, the first controlled study, liver disease per se appears to cause sexual dysfunction and sex hormone changes but these changes are amplified by ethanol.

Expression of the common acute lymphoblastic leukaemia antigen (CALLA gp100) in the brush border of normal jejunum and jejunum of patients with coeliac disease

Expression of the gp100 common acute lymphoblastic leukaemia antigen (CALLA) was studied in the mucosa of the gut by means of indirect immunofluorescence on cryostat tissue sections with a panel of eight monoclonal antibodies to common acute lymphoblastic leukaemia antigen (anti-CALLA antibodies) and two antibodies to non-CALLA leukaemic antigens. Expression of CALLA was absent from normal stomach epithelium, adult and fetal colonic epithelium of normal histology, and colonic epithelium from patients with Crohn's disease or ulcerative colitis. By contrast, all eight anti-CALLA antibodies gave a characteristic reaction in normal adult and fetal small bowel mucosa, with specific localisation to the entire brush border of jejunal epithelium. Whereas seven of these antibodies reacted both with normal jejunal epithelium and with the damaged epithelium of patients with coeliac disease, antibody RFAL-2 reacted strongly only with histologically normal small bowel but more weakly in patients with coeliac disease to a degree related to the amount of histological abnormality. Expression of the moeity like CALLA identified with RFAL-2 was strongest in crypt epithelium and proportionally diminished along the villi according to the amount of histological damage in coeliac disease, being essentially absent in patients with "subtotal villous atrophy."

Pyrimidine nucleoside phosphorylase activity in tumour and matched normal gastrointestinal mucosa

5-Fluorouracil (5-FU) requires activation to the metabolites FdUMP and FUTP for its cytotoxic effect. This activation involves the intracellular enzymes uridine and thymidine phosphorylase. We have assayed the levels of these enzymes in colorectal and gastric cancers and have shown that, in the majority of cases, the enzyme levels were higher than in the adjacent normal mucosa. It is suggested that, while the ratio tumour/normal mucosa enzyme activity may give some indication of the relative toxicity of 5-FU in these tissues, the absolute activities of the phosphorylases in tumour tissue could give a better indication of tumour responsiveness.

Case report. Rapid development of cerebral atrophy due to perinatal herpes simplex encephalitis

A case of neonatal herpes simplex virus (HSV) encephalitis is reported in which diffuse cerebral hemorrhagic lesions were seen in the neonatal period. Severe progressive cortical atrophy with parenchymal calcification developed over the subsequent 9 months, resulting in a striking computed tomography (CT) appearance. The range of CT findings in neonatal HSV encephalitis is reviewed, and differential diagnostic considerations in the present case are discussed.