Dysregulation of sphingolipid and sterol metabolism by ApoE4 in HIV dementia

BACKGROUND

Polymorphisms in apolipoprotein E have been associated with worse prognoses in numerous neurodegenerative conditions, including HIV dementia (HIVD). Despite these correlative observations, there has been little evidence suggesting a mechanism whereby the expression of ApoE4 renders neurons susceptible to insult.

METHODS

Electrospray ionization tandem mass spectrometry was used to quantify levels of sphingolipids and sterols in brains of HIVD patients. Data were stratified according to APOE genotype.

RESULTS

The authors found evidence of dysregulated lipid and sterol metabolism in HIVD patients with an APOE4 genotype. They also found elevations of sphingomyelin, ceramide, and cholesterol in the medial frontal cortex, parietal cortex, and cerebellum of HIVD patients with an APOE3/4 or APOE4/4 genotype compared with HIVD patients with an APOE3/3 genotype. There was no difference in the number of astrocytes or activated microglia in any brain region of the two patient populations, suggesting that modification of lipid metabolism in HIVD patients with an APOE4 genotype was not the result of increased CNS inflammation.

CONCLUSIONS

HIV dementia patients with an APOE4 genotype may be sensitized to neural insults because of dysregulations in lipid metabolism.

Measurement of trace metal influx in plants: a case study with Co

The analysis of transport systems involved in the uptake of trace metals in plants is complicated by technical difficulties associated with measurement of uptake and by the likely presence of multiple transporters with broad specificity. In this study, influx of Co was used to illustrate the problems involved and potential solutions. Issues surrounding kinetic descriptions of transport, multiple uptake systems, specificity of transporters, pH effects and the role of membrane surface charge in determining fluxes are addressed. A list of criteria for validation of flux measurements is provided.

Evaluation of the long term outcome of patients with extremity desmoids

BACKGROUND

The optimum management and long-term outcome for patients with extremity desmoids remains unclear. The aim of this study was to evaluate the long-term outcome of patients with extremity desmoids and to compare patient episodes treated with surgery alone with those treated by radiotherapy either alone or with surgery at any stage of the patient's disease.

METHODS

All patients with extremity desmoids followed at an oncology clinic with an interest in soft tissue tumours and treated between 1959 and 1996 were identified. All were traced back to their primary presentation and first treatment episode.

RESULTS

During the study period 42 patients, 29 females and 13 males were identified. Median follow-up of the patient population was 12.5 years (range 3-30.9). Median age at presentation was 27 years (range 1-69). The lesion was in the upper limb or shoulder in 18, lower limp or pelvis 17 and head and neck 7. Forty patients underwent operation as their primary treatment, 25 of whom developed recurrent tumour. In all there were 41 recurrences following 78 episodes of surgery alone. This compared to 10 recurrences following 16 episodes of radiotherapy or radiotherapy with surgery (p = 0.467). There was no association between primary, first or second recurrence and the development of a further relapse. The median interval to recurrence after surgery alone was 12 months (interquartile range (IQR) 6-13) as opposed to 52 months (IQR 33-62) for patients treated with primary or adjuvant radiotherapy (p= 0.004).

CONCLUSION

Results are poor after both radiotherapy and surgery for extremity desmoids and research into other methods of managing this rare condition need to be considered.

Carcinogenic potential of commonly used hernia repair prostheses in an experimental model

Background

The purpose of this study was to assess the carcinogenic potential of commonly used hernia repair prostheses in an animal model.

Methods

Three types of prosthetic material (monofilament polypropylene, multifilament polypropylene and expanded polytetrafluoroethylene) were implanted in CBA/H mice. Flat (1 cm2) and rolled pieces of the same material were placed subcutaneously in either flank, and a further flat piece was placed in the preperitoneal space. Owing to a high incidence of mesh extrusion in the polypropylene groups, the study protocol was modified to allow only preperitoneal placement of the material. A fourth, control, group had the pockets for the prostheses created but no material implanted. After modification of the protocol there were approximately 60 mice in each group. The mice were followed for 2 years, then killed and assessed histologically for tumour development.

Results

No sarcoma developed at the site of mesh implantation in any of the groups.

Conclusion

This study indicates that the risk of sarcoma formation at the site of hernia repair prostheses is very low.

Determining the influential depth for surface reflectance of sediment by BRDF measurements

We measure the Bi-directional reflectance distribution function (BRDF) of ooid sand layers with three particle size distributions (0.5-1mm, 0.25-0.5mm and 0.125-0.25mm) and layer thicknesses on a reflecting mirror to determine the influential depth in the optical region at wavelengths of 658 nm (red), 570 nm (green) and 457 nm (blue). The hemispherical reflectance (albedo) was used as an indicator of BRDF changes between different layers. Measurements are carried out on both dry and water wetted grains. The results indicate that for both dry and wet and all size distributions, the influential depth is at most 2mm.

Identification of poorly differentiated synovial sarcoma: a comparison of clinicopathological and cytogenetic features with those of typical synovial sarcoma

AIMS

Poorly differentiated areas in synovial sarcomas (SS) are known to be associated with a poorer prognosis. The aim of our study was to describe the morphological spectrum of poorly differentiated synovial sarcomas (PDSS) and refine the criteria for their recognition.

METHODS AND RESULTS

The clinicopathological features of 28 PDSS were compared with those of 26 classic SS. Common cell types in PDSS included epithelioid, spindle and Ewing sarcoma-like small round cells. Unusual features included presence of desmoplastic small cell tumour-like areas and extraskeletal myxoid chondrosarcoma-like areas. The presence of necrosis (P = 0.002), a mitotic rate over 10/10 high-power fields (P < 0.001), a haemangiopericytomatous vascular pattern (P < 0.001) and vascular invasion (P = 0.003) were significantly associated with PDSS, while mast cells (P < 0.001), calcification (P < 0.001) and hyaline bands (P < 0.001) were significantly associated with classic SS. Poorly differentiated areas showed increased proliferative activity with Ki67. PDSS showed a tendency to be larger (P = 0.008) and to be located in proximal more than distal sites (P = 0.025). Three entirely poorly differentiated tumours were diagnosed by demonstration of the t(X;18)(p11;q11) translocation. PDSS showed additional cytogenetic abnormalities.

CONCLUSIONS

Poorly differentiated synovial sarcomas show a spectrum of histological features, which may simulate other malignant neoplasms. The diagnosis of entirely poorly differentiated synovial sarcomas requires cytogenetic analysis.

Fibromyxoid areas and immature osteoid are associated with recurrence of primary aneurysmal bone cysts

AIMS

Primary aneurysmal bone cysts have a high recurrence rate following curettage. The aim of this study was to determine clinicopathological features associated with recurrence of aneurysmal bone cysts.

METHODS AND RESULTS

The clinicopathological features of 86 patients (37 males, 49 females, age range 5-62 years) with aneurysmal bone cysts were reviewed. Recurrence rates following curettage and excision were 32.7% and 5.6%, respectively (P = 0.028). The association of clinicopathological features with recurrence was studied in a subset of 45 patients treated by curettage. The presence of nodular fasciitis-like fibromyxoid areas [P = 0.033, odds ratio (OR) = 9.17, 95% confidence interval (CI) 1.06, 79.39] and immature osteoid with active osteoblasts (P = 0.041, OR = 3.7, 95% CI 1.03, 13.35) was significantly associated with an increased risk of recurrence. Clinical and radiological features were not associated with recurrence. In a multivariate analysis, the presence of immature osteoid was a better predictor of recurrence than radiological activity (hazard ratio = 3.18, 95% CI 1.04, 9.73, P = 0.043). There was no statistically significant association between radiological activity and histological features.

CONCLUSIONS

Aneurysmal bone cysts with nodular fasciitis-like fibromyxoid areas and immature osteoid with active osteoblasts are more likely to recur. Mention of these features in histopathology reports will help to identify patients who require closer follow-up. Lesions that are apparently radiologically inactive may show fibroblastic and osteoblastic proliferation and therefore may recur.

Myositis ossificans and fibroosseous pseudotumor of digits: a clinicopathological review of 64 cases with emphasis on diagnostic pitfalls

Myositis ossificans (MO) and fibroosseous pseudotumor of digits (FP) are pseudotumoral mimics of malignancy. A review of 50 cases of MO and 14 cases of FP showed that a malignant diagnosis was suggested by referring pathologists in 23% of MO and 9% of FP. The most common misdiagnosis was osteosarcoma. Awareness of the spectrum of clinicopathological features of MO and FP will help pathologists avoid misdiagnoses. A comparison of the clinicopathological features of MO and FP showed that most features were similar, but FP involved an older age group (p<0.001). MO showed a statistically significant higher tendency to contain fibrinous material (p=0.007), edematous lymphangioma-like areas (p=0.013), and cartilage (p=0.017) and FP to contain excessive immature osteoid (p=0.029). These differences may be related to the site of occurrence.

Management of soft tissue sarcomas of the abdomen and pelvis

OBJECTIVE

Soft tissue sarcomas of the abdomen or pelvis are rare tumours that usually arise in the retroperitoneum but may also arise from the gastrointestinal tract or other abdominal organs. The aim of this study was to assess patient outcome following treatment of these tumours at a tertiary referral centre.

PATIENTS AND METHODS

Data on all patients with soft tissue tumours treated under the care of one surgeon between January 1990 and December 2000 was reviewed.

RESULTS

Over the 11-year period 61 patients underwent 79 operations for a soft tissue sarcoma of the abdomen or pelvis. Macroscopic clearance of tumour at operation was achieved in 45 (74%) of the 61 patients, for primary tumours this was 97%, recurrent tumours 50% and metastases 33%. The median survival for those undergoing complete resection was 50 months (range 3-238 months, median follow-up 33 months). This compared with a median survival of only 6 months range (1-127 months) for those that had incomplete resection (P = 0.001). The 5-year survival for patients that had complete resection was 61.5%, however, over one-third of the 5-year survivors have since recurred.

CONCLUSION

This study confirms that most primary soft tissue sarcomas of the abdomen or pelvis are resectable and the majority of patients will experience a long disease free interval following resection.

Fluoxetine improves functional work capacity in women with premenstrual dysphoric disorder

Interference with social and occupational functioning is a key criterion for premenstrual dysphoric disorder (PMDD) and distinguishes it from the less severe premenstrual syndrome (PMS). We conducted a post hoc analysis of the results of a previously reported study evaluating the efficacy of fluoxetine in the management of PMDD, to determine the extent to which women with PMDD perceived impairment in their functional work capacity during the luteal phase of their menstrual cycle. The effects of two doses of fluoxetine vs placebo in alleviating PMDD symptoms and restoring normal work capacity during this period were assessed. We measured baseline follicular vs luteal phase presence of 8 patient-rated functional work capacity-related symptoms on the Premenstrual Tension Scale-Self Rated in 320 women who met diagnostic criteria for late luteal phase dysphoric disorder, now known as PMDD. Women were then randomized to double-blind treatment with either fluoxetine 20 mg/d, fluoxetine 60 mg/d, or placebo daily for 6 menstrual cycles. All 8 work capacity-related symptoms were more likely to be present in the baseline luteal phase than in the baseline follicular phase. A statistically significant improvement from baseline to the average treatment score for the work capacity subscale was detected for both fluoxetine groups compared to the placebo group. This beneficial response to fluoxetine was evident by the first cycle of treatment. Our results demonstrate that fluoxetine at a relatively low dose of 20 mg/d quickly reduced symptoms that negatively affect work capacity and was well tolerated.

Effect of pregnancy on bone mineral density and biochemical markers of bone turnover in a patient with juvenile idiopathic osteoporosis

Juvenile idiopathic osteoporosis (JIO) is rare, presenting with vertebral fractures in the immediate prepubertal years; however, recovery is normally observed. We report the case of a 19-year-old pregnant woman previously diagnosed with JIO. She experienced three vertebral fractures in the third trimester of pregnancy. She delivered by caesarean section at 38 weeks gestation. Spinal bone mineral density decreased by 25%, hip bone mineral density by 10%, and forearm bone mineral density by 3% during pregnancy. Bone resorption markers, free pyridinoline and deoxypyridinoline (fPYD and fDPD), were elevated at baseline and markedly increased during pregnancy (fPYD/fDPD at 0, 10, 15, 20, and 28 weeks and immediately postpartum: 36.2/11.5, 52.9/15.8, 54.3/13.3, 51.1/13.3, 90/21.8, and 95.6/22.7 nmol/mmol creatinine, respectively) The bone formation marker, bone-specific alkaline phosphatase (BSAP), was within the reference range at baseline and increased in the third trimester. (BSAP at 0, 10, 15, 20, and 28 weeks and immediately postpartum: 20.5, 18.3, 17.7, 19.8, 26.9, and 30.0 U/liter, respectively). Parathyroid hormone (PTH) was measured by two methods to assess the possible effect of PTH fragments. PTH(1-84) (Roche) showed little change during the pregnancy, whereas the Nichols assay [(1-84) and(7-84) PTH fragment], revealed increases paralleling the changes in bone resorption. This young woman's bone turnover showed an exaggerated response to pregnancy, with bone resorption predominating over formation. PTH fragments may have partially mediated this effect.

Derivative analysis of absorption features in hyperspectral remote sensing data of carbonate sediments

This study uses derivative spectroscopy to assess qualitative and quantitative information regarding seafloor types that can be extracted from hyperspectral remote sensing reflectance signals. Carbonate sediments with variable concentrations of microbial pigments were used as a model system. Reflectance signals measured directly over sediment bottoms were compared with remotely sensed data from the same sites collected using an airborne sensor. Absorption features associated with accessory pigments in the sediments were lost to the water column. However major sediment pigments, chlorophyll a and fucoxanthin, were identified in the remote sensing spectra and showed quantitative correlation with sediment pigment concentrations. Derivative spectra were also used to create a simple bathymetric algorithm.

Where is it coming from?

A case report is presented of an unusual situation where standard routine diagnostic methods failed to reveal the true origin of an endodontic infection.

The utility of plasma CRH as a predictor of preterm delivery

It has been suggested that CRH is a placental clock that controls the duration of pregnancy and that the timing of the rise in CRH may permit prediction of the onset of labor. We have performed a prospective longitudinal study, in 297 women, to examine the utility of a single second-trimester plasma CRH measurement to predict preterm delivery. Venous blood samples were taken at 4-weekly intervals, beginning at 16-20 wk gestation, until delivery for CRH and its binding protein. A time point at which a single plasma CRH test might give optimal data to predict preterm delivery was determined. Thirty-one subjects delivered prematurely (10.4%). Sampling for plasma CRH at 26 wk gestation seemed the optimal time point to maximize sensitivity and specificity of the test. The mean (+/- SD) plasma CRH in women at this gestation who eventually delivered after spontaneous labor within 1 wk of their due date (39-41 wk, n = 127) was 34.7 +/- 27.0 pM. A plasma CRH of more than 90 pM at 26 wk gestation had a sensitivity of 45% and a specificity of 94% for prediction of preterm delivery. The positive predictive value was 46.7%. Calculation of free CRH did not improve these figures. In conclusion, a single measurement of plasma CRH, toward the end of the second trimester, may identify a group at risk for preterm delivery, but over 50% of such deliveries will be unpredicted. These data do not support the routine clinical use of plasma CRH as a predictor of preterm labor.

Intraoperative radioguided thoracoscopic removal of ectopic parathyroid adenoma

Twenty-five percent of primary hyperparathyroidism is caused by ectopic mediastinal parathyroid glands, with 2% of these not accessible to standard cervical surgical approaches. Advancement in video-assisted thoracoscopic surgical techniques has decreased the need for sternotomy to successfully remove these ectopic glands. The thoracoscopic approach, however, is limited by the surgeon's inability to always accurately visualize ectopic glands. Intraoperative radionuclide-guided dissection, using a thoracoscopic approach, provides a novel adjunct to the removal of occult ectopic parathyroid glands. We report a case of an occult ectopic parathyroid adenoma removed thoracoscopically using an intraoperative handheld gamma probe.

Cluster and regional influences on suicide in a Southwestern American Indian tribe

Suicide is the second leading cause of death among American Indian youth. Elevated rates of suicide in Indian communities have been attributed both to outbreaks and to regional trends. We assessed the contribution of these two factors for a single tribe, and attempted to define a profile of individuals at risk. Data came from the tribe's registry of suicide attempts and completions for 1990-1993 and analysis of death certificates for the period 1985-1996. Using combined tribal and death certificate data, the average annual (age-adjusted) rate of completed suicide among tribal members was 44.7/100,000 for 1990-1993. Within the 45 suicide deaths and serious attempts in this time period, we identified one grouping of seven cases taking place in a 40-day period. All seven involved hanging and youth (13-28 years old). Using death certificate data alone, the average annual rate of suicide death for non-natives in the surrounding county in the period 1985-1996 was 22.7/100,000. Age-adjusted to the county population, the tribal rate for the same period was not significantly different (24.6/100,000). Tribal and county suicide patterns differed by age distribution and method but not by gender. We concluded that both regional trends and clustering contribute to suicide in this community. Further prevention efforts may need to focus on both unique tribal characteristics and shared factors among non-native neighbors.

A randomised trial of oral versus vaginal administration of misoprostol for the purpose of mid-trimester termination of pregnancy

A prospective randomised controlled trial was undertaken to compare the efficacy of two routes of administration, oral versus vaginal, of the prostaglandin E1 analogue misoprostol (Cytotec) to effect termination of pregnancy in the mid-trimester. Fifty-five women were recruited into the trial; 26 to receive all doses orally and 29 via the vaginal route. The dosing regimen was 400 microg as the initial dose followed by a second dose of 200 microg two hours later and then four-hourly 200 microg doses until delivery or 32 hours from commencement of treatment. If delivery had not been effected by the last dose of misoprostol, a Syntocinon infusion was started synchronously Misoprostol administered vaginally was significantly more effective than when administered orally as judged by induction-to-delivery interval and also the need or otherwise to augment therapy with a Syntocinon infusion. The average induction-to-delivery interval was 17.5 hours in the vaginal group compared to 33 hours in the oral group (p = 0.0003). The percentages of women who delivered at 24 and 48 hours were 93% and 100% in the vaginal administration group and 19% and 70% in the oral administration group (p < 0.05). No significant differences in complication rates or side effects were noted between the two groups

The potential for improvement in outcome of children with intussusception in the South Island

AIMS

To review the experience in the South Island to predict the extent to which the outcome in intussusception might be expected to improve by the introduction of management guidelines and access to a regional specialist paediatric surgical service.

METHODS

Children with intussusception treated in the South Island during an eleven year period until 1998 were identified from hospital coding systems, the Southern RegionalHealth Authority and from departmental audit programmes. Details of management and outcome were analysed.

RESULTS

Data proved difficult to obtain. There were 83 children identified with intussusception confirmed on enema or at surgery; 76 had an enema that was successful in 44. Delayed repeat enema and gas enema techniques were not used as frequently as might be expected. The operative rate was higher than that reported by other centres.

CONCLUSIONS

Current data, coding and audit systems have significant short comings, which limit availability of reliable outcome data. Increased awareness of the expanded indications for enema reduction, use of air (rather than barium) and delayed repeat enemas, and access to specialist paediatric surgical involvement appears to increase the nonoperative rate. Implementation of guidelines for the management of intussusception might be expected to reduce by more than half the number of children undergoing surgery for this condition in the South Island.

[The six minute walking test elicits lung hyperinflation in patients with severe chronic obstructive lung disease]

BACKGROUND

Exercise tolerance in patients with COPD is highly variable and poorly related to airways obstruction assessed by FEV1. These patients develop dynamic hyperinflation (DH) during an incremental exercise test which can be evaluated through a reduction in inspiratory capacity (IC).

AIM

To evaluate: a) if the six minute walking test (6 MWD) induce DH reducing IC, b) if the reduction in IC is related to tidal expiratory flow limitation at rest (FL).

SUBJECTS AND METHODS

Thirty eight stable COPD patients (28 FL and ten non FL during resting breathing, determined by the negative pressure technique). Inspiratory capacity was measured before and immediately after the 6 MWD test. Dyspnea, SpO2 and heart rate were measured before and after the test.

RESULTS

Inspiratory capacity was lower in FL patients as compared to patients without FL (p < 0.005). Although no differences were found between groups in 6 MWD, dyspnea and HR, a significant reduction in IC after the walking test was observed only in FL patients (p < 0.0001). In addition, SpO2 fell significantly (p < 0.0001) after walking in the same group.

CONCLUSIONS

Our results demonstrate that a moderate exercise such as the walking test induces DH and hypoxemia in patients with COPD and FL and stresses the importance of assessing DH by measuring IC in these patients.

A retroperitoneal bronchogenic cyst: a rare cause of a mass in the adrenal region

This report documents a bronchogenic cyst presenting as an adrenal tumour in a 51 year old man with persistent epigastric pain. The cyst is regarded as a developmental abnormality of the primitive foregut, which typically occurs in the chest. Subdiaphragmatic, and retroperitoneal locations in particular, are unusual. The differential diagnosis of a bronchogenic cyst in the retroperitoneum includes cystic teratoma, bronchopulmonary sequestration, cysts of urothelial and mullerian origin, and other foregut cysts.