Detection of cytomegalovirus reactivation in cancer patients receiving chemotherapy.

While increasing numbers of cytomegalovirus (CMV)-associated diseases are occurring in patients undergoing conventional chemotherapy, information regarding CMV reactivation is limited. This pilot study was conducted to investigate CMV reactivation induced by chemotherapy. Seven blood samples were collected from each of 15 patients with newly diagnosed malignant disease, at baseline before chemotherapy, and once every month after chemotherapy was commenced. CMV viral loads in leukocytes were determined by real-time PCR. Host responses to changes in viral loads were assessed by assaying CMV-specific IgG titres and tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma levels in each of the blood samples, and by scoring the number of CMV-associated clinical symptoms that developed. All except one patient experienced CMV reactivation during the course of chemotherapy, with the average viral load peaking after the third course of treatment. Titres of CMV-specific IgG increased in line with the increase in viral load. Plasma levels of TNF-alpha and IFN-gamma initially decreased from baseline, and then rose to peak levels at the same time as, or shortly after, the highest viral loads were recorded. Clinical symptoms potentially attributable to CMV infection appeared as the viral load increased. It was concluded that the incidence of CMV reactivation in patients receiving conventional chemotherapy is high. Reactivation is not asymptomatic, but was self-limiting in most of these cases. Increases in plasma TNF-alpha and IFN-gamma occur after reactivation, but not before.

Aldose reductase-deficient mice develop nephrogenic diabetes insipidus.

Aldose reductase (ALR2) is thought to be involved in the pathogenesis of various diseases associated with diabetes mellitus, such as cataract, retinopathy, neuropathy, and nephropathy. However, its physiological functions are not well understood. We developed mice deficient in this enzyme and found that they had no apparent developmental or reproductive abnormality except that they drank and urinated significantly more than their wild-type littermates. These ALR2-deficient mice exhibited a partially defective urine-concentrating ability, having a phenotype resembling that of nephrogenic diabetes insipidus.

Evaluation of a new transcutaneous bilirubinometer in Chinese newborns.

OBJECTIVE: To evaluate the use of a new transcutaneous bilirubinometer (JM-103 Minolta Airshields) for detection of hyperbilirubinaemia in term or near-term healthy Chinese newborns. METHODS: Transcutaneous bilirubin (TcB) was used to screen for severe hyperbilirubinaemia in newborn infants. Blood was taken for total serum bilirubin (TSB) measurement if the initial TcB level was higher than the 40th centile in Bhutani's nomogram. Paired TcB and TSB results were then reviewed over 6 months. The correlation as well as the mean difference between the two methods were calculated. The clinical application of TcB with Bhutani's nomogram in the prediction of severe hyperbilirubinaemia in low-risk, medium-risk and high-risk thresholds for phototherapy was also analysed. RESULTS: 997 paired TcB and TSB measurements were evaluated in term or near-term newborns. TcB was significantly correlated with TSB, with a correlation coefficient of 0.83 (p<0.001). Their mean difference was 21.7 micromol/l (SD 21.2, p<0.001), with the 95% limits of agreement between -19.9 and 63.3 micromol/l. In both low-risk and medium-risk thresholds for phototherapy, using the 75th centile of Bhutani's nomogram as threshold, TcB could identify all cases and had a sensitivity and negative predictive value of 100% each, a specificity of 56% and positive predictive value of 23%. For high-risk cases, using the 75th centile as cut-off, the sensitivity and negative predictive value were reduced to 86.7% and 97.0%, respectively. CONCLUSION: An accurate point-of-care bilirubin analyser facilitates bilirubin screening and avoids unnecessary blood tests. Although using the transcutaneous bilirubinometer JM-103 might result in a significant difference between TcB and TSB measured in Chinese newborns, combining the use of TcB and the 75th centile in Bhutani's nomogram as the cut-off level can identify all cases of significant hyperbilirubinaemia.

Prenatal fat-rich diet exposure alters responses of embryonic neurons to the chemokine, CCL2, in the hypothalamus.

Maternal consumption of a high-fat diet (HFD) during pregnancy is found to stimulate the genesis of hypothalamic orexigenic peptide neurons in the offspring, while HFD intake in adult animals produces a systemic low-grade inflammation which increases neuroimmune factors that may affect neurogenesis and neuronal migration. Building on this evidence and our recent study showing that the inflammatory chemokine, CCL2, stimulates the migration of hypothalamic neurons and expression of orexigenic neuropeptides, we tested here the possibility that prenatal exposure to a HFD in rats affects this chemokine system, both CCL2 and its receptors, CCR2 and CCR4, and alters its actions on hypothalamic neurons, specifically those expressing the neuropeptides, enkephalin (ENK) and galanin (GAL). Using primary dissociated hypothalamic neurons extracted from embryos on embryonic day 19, we found that prenatal HFD exposure compared to chow control actually reduces the expression of CCL2 in these hypothalamic neurons, while increasing CCR2 and CCR4 expression, and also reduces the sensitivity of hypothalamic neurons to CCL2. The HFD abolished the dose-dependent, stimulatory effect of CCL2 on the number of migrated neurons and even shifted its normal stimulatory effect on migrational velocity and distance traveled by control neurons to an inhibition of migration. Further, it abolished the dose-dependent, stimulatory effect of CCL2 on neuronal expression of ENK and GAL. These results demonstrate that prenatal HFD exposure greatly disturbs the functioning of the CCL2 chemokine system in embryonic hypothalamic neurons, reducing its endogenous levels and ability to promote the migration of neurons and their expression of orexigenic peptides.

CT scan in inter hemispheric subdural hematoma. Clinical and pathological correlation.

In a patient with a large interhemispheric subdural hematoma, the CT scan showed a radiodensity with a straight sagittal and a convex lateral border. This image correlated with the autopsy findings. It differs from CT scan images of intracerebral hematomas.

The "turning off" of excessive cell replicative activity in advanced atherosclerotic lesions of swine by a regression diet.

We studied progression of atherosclerotic lesions in the coronaries and abdominal aortas of swine fed hyperlipidemic (HL) diets producing serum cholesterol levels of about 700 mg/dl for up to 18 months with killings at 9, 13.5 and 18 months on diet. We studied changes in lesions in subsets given after 9 months on the HL diet a low fat, low cholesterol mash diet with killings at 4.5 and 9 months on the regression diet. Lesion cell numbers were evaluated using mean nuclear profiles per cross-section (Np/Cx) in an anatomically defined portion of artery as an index. Lesion sizes were evaluated using mean cross-sectional area (area/Cx) as an index. Tritiated thymidine labeling indices (LI) were used as an index of cell proliferative activity in the coronaries. We also determined the percentage of lesions occupied by lipid rich calcific necrotic debris. For further comparisons all of the same values were determined for normal intimal cell masses (ICM) in control groups fed a low fat, low cholesterol mash diet throughout. The atherosclerotic lesions in the HL swine appeared to arise mainly in the ICM. These became lesions and increased tremendously in size and cell numbers. The greatest increase was in the abdominal aorta even when lesion values were normalized by being expressed as percentages of the wall (intima + media). Lipid-rich calcific necrotic debris occupied about 25% of the lesion by 9 months and the percentage was similar at 18 months although size of lesions and their necrotic regions had increased 3-fold over the 9-month interval. Lesion [3H]thymidine LIs were 3-4-fold greater than in the control ICM. In the period 9-18 months on an HL diet lesions increased about 3-fold in size and cell numbers. In the swine put on a regression diet for the 9-18 month period growth of the lesions stopped completely. In fact, there was a numerical decrease in lesion sizes and cell numbers and this was statistically significant for the left anterior descending coronary. The lesion growth stoppage was partly accounted for by the "turning off" of excessive DNA synthesis activity of the lesion cells as indicated by the return of [3H] thymidine LIs to the normal values in the mash controls. Another factor was the lack of increase and in fact marked reduction in the size of the regions of lipid rich necrotic debris.(ABSTRACT TRUNCATED AT 400 WORDS)

Intestinal apolipoprotein B-48 synthesis and lymphatic cholesterol transport are lower in swine fed high fat, high cholesterol diet with soy protein than with casein.

Effects of dietary proteins on intestinal lipoproteins were studied in 8 Yorkshire swine fed a high fat, high cholesterol diet with either casein or soy protein. After 5 weeks of feeding, the casein group exhibited moderately elevated levels of serum cholesterol (334 +/- 46 mg/dl). The soy protein group showed significantly less hypercholesterolemia as compared to the casein group (122 +/- 8 mg/dl). Swine were subjected to cannulation of mesenteric lymph duct under halothane anesthesia. A single dose of 250 microCi [14C]cholesterol and 10 mCi [3H]leucine was infused into the upper jejunum 2 h after one-fifth of daily food was given. The 3-h lymphatic transport of cholesterol in casein-fed swine was significantly higher than in those fed soy protein. Triglyceride transport values were similar in the 2 groups. The [3H]leucine incorporation study revealed that transport of apo B-48 bore a significant positive relationship to transport of cholesterol in both chylomicron and VLDL fractions of mesenteric lymph. A greater apo B-48 secretion with higher specific activity was probably responsible for the greater transport of cholesterol in chylomicrons in casein-fed than in soy protein-fed swine. Similarly, the transport of lymph VLDL cholesterol in swine fed casein or soy protein paralleled the amount of accompanying apo B-48. Dietary proteins probably influence the intestinal synthesis of apo B-48 which in turn affects cholesterol transport into the lymphatics.

Modification of lipoprotein patterns and retardation of atherogenesis by a fish oil supplement to a hyperlipidemic diet for swine.

We have studied the effect of addition of 30 ml cod liver oil (FO) daily to a highly atherogenic butter (BT) diet for swine on lesion development in the coronary arteries and aorta, plasma lipoprotein (LP) patterns, plasma levels of thiobarbituric acid-reactive substances (TBARS) and on tritiated thymidine-labeling indices ([3H]TdR LI) of smooth muscle cells (SMC) and monocyte/macrophages (M/M phi) in the atherosclerotic lesions. Seventeen male Yorkshire swine (11.1 +/- 0.4 kg) were divided into 3 groups: BT (n = 6), BT + FO (n = 6) and mash (n = 5). They were fed the respective diets for 4 months. Terminally, fasting plasma was obtained and cholesterol contents were determined in various fractions of lipoproteins separated by density gradient ultracentrifugation, Pevikon block electrophoresis and immunoelectrophoresis. Apoprotein (B, A-I, E and C) contents of the plasma and lipoprotein fractions were determined by polyacrylamide gel electrophoresis and densitometry of gels stained with Coomassie blue. Swine were injected intramuscularly with 0.5 mCi/kg of [3H]TdR 2 h before death. The aorta and coronary arteries were perfusion fixed in situ under anesthesia. Samples were obtained for microscopic morphometry, autoradiography and immunohistochemistry from distal abdominal aorta, thoracic aorta, and proximal coronary arteries; left main (LM), left anterior descending (LAD), left circumflex (LCX), right main (RM), and right coronary artery (RCA). On the BT diet without FO there was extensive atherosclerotic (AS) lesion development, which was drastically reduced by the addition of FO to the BT diet in all sites by from 71 to 94%. The overall plasma cholesterol (CH) levels were reduced only modestly by the FO (816 +/- 64 to 629 +/- 14 mg/dl) but the distribution of CH in the various lipoprotein classes was remarkably altered. The CH in the large lipoprotein molecules containing both B and E apoproteins was reduced from 488 +/- 84 to 204 +/- 17 mg/dl by the FO with an almost corresponding increase in the conventional LDL molecules containing apo B only (158 +/- 29 to 344 +/- 15 mg/dl). We offer the hypothesis that the large apo B,E containing molecules are much more atherogenic than the smaller apo B containing molecules. This hypothesis is supported by a highly significant correlation between extent of lesion development in all arterial sites and plasma levels of CH in apo B,E containing lipoproteins. Plasma TBARS were elevated by the BT + FO diet but seemed to have no significant effect on the lesions.(ABSTRACT TRUNCATED AT 400 WORDS)

Biochemical pharmacology of acyclic nucleotide analogues.

Our studies have shown that the acyclic nucleotide analogues PMEA and HPMPC are able to penetrate into cells and are then activated to mono- and diphosphate derivatives. The latter correspond to triphosphate analogues and presumably serve an important role in the biological activity exerted by these antiviral agents. In support of this idea, the inhibitory effect of PMEApp on HIV reverse transcriptase has been demonstrated with both RNA and DNA template-primer systems. Further studies will be undertaken to determine the effect of HPMPCpp on viral DNA polymerases. Whereas the metabolism of PMEA in CEM cells gives rise to only PMEAp and PMEApp, additional metabolites were obtained in MRC-5 cells; the identity of these metabolites remains to be determined. In the case of HPMPC, a third metabolite was obtained in addition to HPMPCp and HPMPCpp, which has been tentatively assigned as a phosphate-choline adduct by analogy with activation of cytosine-based nucleoside derivatives. The metabolism of HPMPC was unchanged between uninfected and infected cells, indicating that viral enzymes are not necessary for the activation of HPMPC. The long intracellular half-lives of the HPMPC metabolites may have implications for the antiviral efficacy of this compound. The persistence of activated metabolites suggests that infrequent dosing may be possible due to a prolonged antiviral effect. Our results on the effectiveness of infrequent dosing schedules with HPMPC in the treatment of HSV 2 infections in mice support this hypothesis. It is also possible that HPMPCp-choline may serve as a reservoir for HPMPC and therefore for the presumed active metabolite HPMPCpp.

Evaluation of "point of care" devices in the measurement of low blood glucose in neonatal practice.

BACKGROUND: Low blood glucose in newborns is difficult to detect clinically. Hence a reliable "point of care" device (glucometer) for early detection and treatment of low glucose is needed. OBJECTIVE: To evaluate the performance of five readily available glucometers for the detection of low blood glucose in newborn infants. METHOD: Glucostix measurements were taken for newborns with risk factors using a Reflolux S (Boehringer) glucometer. If the initial reading was low (< 2.6 mmol/l), further measurements were taken with two other glucometers (phase I, Advantage and Glucotrend (Roche); phase II, Elite XL (Bayer) and Precision (Abbott)), and plasma glucose was measured in the laboratory (Aeroset; Abbott). RESULTS: Over 10 months, 101 specimens were collected from 71 newborns (57 in phase I; 44 in phase II). The Advantage glucometer usually overestimated blood glucose with a mean difference of 1.07 mmol/l (p < 0.01) at all low glucose ranges. The Glucotrend, Precision, and Elite XL glucometers performed better; the mean differences were not significantly different from the laboratory measured value (0.17 mmol/l (p = 0.37); -0.12 mmol/l (p = 0.13), and 0.24 mmol/l (p = 0.13) respectively). For detection of glucose concentrations < 2.6 mmol/l, the Precision glucometer had the highest sensitivity (96.4%) and negative predictive value (90%). For lower glucose concentrations (< 2.0 mmol/l), the Glucotrend glucometer performed even better (sensitivity 92.3%, negative predictive value 96.3%). CONCLUSION: Point of care devices should have good precision in the low glucose concentration range, sensitivity, and accuracy for early detection of neonatal hypoglycaemia. None of the five glucometers was satisfactory as the sole measuring device. The Glucotrend and Precision glucometers have the greatest sensitivity and negative predictive value. However, confirmation with laboratory measurements of plasma glucose and clinical assessment are still of the utmost importance.

Systemic to pulmonary venous communication (right-to-left shunt) in superior vena cava obstruction demonstrated by spiral CT.

An unusual case of systemic vein to pulmonary vein communication in superior vena cava obstruction is reported. This was a right-to-left shunt, demonstrated by spiral CT and aided by three-dimensional reconstruction. The pulmonary venous shunts were mainly seen in fibro-atelectatic lung where prominent bridging veins were concentrated.

Cerebellar infarction: a clinical and CT study.

Seven patients with computed tomographic (CT) evidence of cerebellar infarction were found during review of all CT records over a 5-year period. CT demonstrated decreased density in 2 distinct anatomic areas, corresponding to the distribution of the posterior inferior cerebellar artery and the superior cerebellar artery. Some patients also had hydrocephalus and fourth ventricular effacement and displacement. The location and extent of infarction do not relate directly to the clinical outcome. Rapid deterioration of the patient's sensorium is the best indication for surgical decompression.

Generation and characterization of sodium-dicarboxylate cotransporter-deficient mice.

The sodium-dependent dicarboxylate cotransporter (NaDC1) has a proposed function of reabsorbing various Krebs cycle intermediates in the kidney and the small intestine. Since Krebs cycle intermediates have been suggested to be important for renal cell survival and recovery after hypoxia and reoxygenation, the transporter may play a role in the recovery of the kidney. Additionally, mutations in the transporter homolog in Drosophila led to fly longevity which was thought to be similar to that induced by caloric restriction (CR). To clarify the role of the sodium dicarboxylate cotransporter in vivo we generated cotransporter-deficient mice. These knockout mice excreted significantly higher amounts of various Krebs cycle intermediates in their urine; thus confirming the proposed function to reabsorb these metabolic intermediates in the kidney. No other phenotypic change was identified in these mice, however. Transporter deficiency did not affect renal function under normal physiological conditions, nor did it have an effect on renal damage and recovery from ischemic injury. Additionally, the absence of the transporter did not lead to metabolic or physiological changes associated with CR. Our results suggest that although the sodium dicarboxylate cotransporter is involved in regulating levels of various Krebs cycle intermediates in the kidney, impaired uptake of these intermediates does not significantly affect renal function under normal or ischemic stress.

Identification of differentially expressed proteins in human malignant pleural effusions.

A high protein concentration in a pleural effusion makes it more likely to be a malignant than a transudative effusion. However, the variability in protein composition between these two forms of pleural effusion is not well understood. In order to compare their protein compositions, the proteomic profiles of 14 malignant and 13 transudative pleural effusions were studied using two-dimensional gel electrophoresis. Protein spots with differential expression were identified by matrix-assisted laser desorption/ionisation quadrupole time-of-flight mass spectrometry and liquid chromatography/tandem mass spectrometry. Targeted proteins were further examined by ELISA and Western immunoassay in all samples. Two-dimensional gel electrophoresis revealed seven spots whose expression was reduced in malignant pleural effusions. Four of the abnormal spots were identified as fibrinogen gamma-chain precursor, two as fibrinogen beta-chain precursor and one as pigment epithelium-derived factor. ELISA and Western immunoassay showed that pigment epithelium-derived factor levels were significantly lower in malignant than in transudative pleural effusions. It has been demonstrated that proteomic technologies may help in the elucidation of variable expression of proteins with particular functions. By applying these technologies, the level of pigment epithelium-derived factor, a potent anti-angiogenic factor, was found to be significantly lower in malignant than in transudative pleural effusions. This finding allows for further exploration regarding how underexpression of pigment epithelium-derived factor may relate to the pathogenesis of malignant pleural effusions.