Colored noise and computational inference in neurophysiological (fMRI) time series analysis: resampling methods in time and wavelet domains

Even in the absence of an experimental effect, functional magnetic resonance imaging (fMRI) time series generally demonstrate serial dependence. This colored noise or endogenous autocorrelation typically has disproportionate spectral power at low frequencies, i.e., its spectrum is (1/f)-like. Various pre-whitening and pre-coloring strategies have been proposed to make valid inference on standardised test statistics estimated by time series regression in this context of residually autocorrelated errors. Here we introduce a new method based on random permutation after orthogonal transformation of the observed time series to the wavelet domain. This scheme exploits the general whitening or decorrelating property of the discrete wavelet transform and is implemented using a Daubechies wavelet with four vanishing moments to ensure exchangeability of wavelet coefficients within each scale of decomposition. For (1/f)-like or fractal noises, e.g., realisations of fractional Brownian motion (fBm) parameterised by Hurst exponent 0 < H < 1, this resampling algorithm exactly preserves wavelet-based estimates of the second order stochastic properties of the (possibly nonstationary) time series. Performance of the method is assessed empirically using (1/f)-like noise simulated by multiple physical relaxation processes, and experimental fMRI data. Nominal type 1 error control in brain activation mapping is demonstrated by analysis of 13 images acquired under null or resting conditions. Compared to autoregressive pre-whitening methods for computational inference, a key advantage of wavelet resampling seems to be its robustness in activation mapping of experimental fMRI data acquired at 3 Tesla field strength. We conclude that wavelet resampling may be a generally useful method for inference on naturally complex time series.

Network 12 hepatitis B vaccination quality improvement program: an educational program directed at physicians, staff, and patients

Hepatitis B is easily spread via contact with infected blood. Hemodialysis patients and staff are particularly at risk for acquiring hepatitis B. Consequently, vaccination of hemodialysis patients and staff is strongly recommended. However, the vaccination rate among dialysis patients in this country remains below 50%. End-Stage Renal Disease (ESRD) Network 12 developed a quality improvement project directed at increasing patient vaccination by regular surveys, reports, and education of physicians, staff, and patients. Seventy-seven percent of facilities in the 4-state Network participated. Overall vaccination rate increased from 66.9% to 73.2% over 18 months (P <.05). The greatest improvement was seen among units with less than 60% of patients vaccinated initially, with mean facility vaccination rate increasing from 31.2 +/- 20.5% to 57.5 +/- 30.1% in the last available data period (P <.001). Only 3 of these 29 units failed to improve. The 90 units that had 60% to 97% vaccination rates initially improved significantly from 79.8 +/- 9.6% to 82.4 +/- 15% (P =.015). Three quarters of these units showed improvement. Only units with 100% vaccination deteriorated, but still maintained vaccination rates of 74.5 +/- 25.6%. An education-based quality improvement project can improve the hepatitis B vaccination rate of hemodialysis patients.

Granulocyte-colony stimulating factor (G-CSF) may improve disease outcome in elderly patients with diffuse large cell lymphoma (DLCL) treated with CHOP chemotherapy

Advanced age is an adverse prognostic factor in patients with DLCL. CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) has frequent dose-limiting toxicities, including myelosuppression. We retrospectively reviewed 50 consecutive patients > 60 years of age (median age 72) with B-cell DLCL who received CHOP with G-CSF. Patients received CHOP (median 6 cycles) at three-week intervals. G-CSF was given following all cycles of chemotherapy ("prophylactic G-CSF") in 28 of 50 patients, and following an episode of febrile neutropenia and thereafter in 19 patients, according to ASCO guidelines. Dose intensity, treatment delays, episodes of febrile neutropenia, complete response (CR) rate, disease-free survival, time-to-treatment failure, and overall survival were all analyzed according to the age-adjusted International Prognostic Index (aaIPI). The actual dose intensity for cyclophosphamide was 225.9 mg/m2/week and 0.90, respectively and for doxorubicin was 14.9 mg/m2/week (90% of ideal CHOP dosing for both drugs). Median followup was 4 years for the patients still living. Treatment delays and episodes of febrile neutropenia were less frequent among patients receiving G-CSF with all cycles of CHOP. The CR rates were 100%, 81%, 85%, and 36% for the low, low-intermediate, high-intermediate, and high aalPI risk groups, respectively. The 5-year actuarial relapse-free and overall survival for our patients were comparable to that of the cohort < or = 60 years of age and superior to the > 60 years of age cohort used to establish the aaIPI. With optimization of CHOP dosing, advanced age may not be an adverse prognostic factor for patients with DLCL. The routine use of G-CSF in elderly patients with DLCL should be further investigated.

Scoring written material from the Mini-Mental State Examination: a comparison of face-to-face, fax and video-linked scoring

We assessed the reliability of scoring written items of the Mini-Mental State Examination (MMSE) using different communication modes: face to face, fax and videoconferencing. A total of 99 MMSEs were recovered from the records of a community mental health team for the elderly. The written parts of the examination (sentence and pentagrams) were scored--in person, using a faxed copy or over the video-link--according to published criteria. Relative to in-person scoring, sentences could be scored reliably when faxed (kappa = 0.80), as could pentagrams (kappa = 0.71). Sentences could be reliably scored over the videoconferencing link (kappa = 0.70), but pentagrams could not (kappa = 0.47). Caution is required before accepting the results of scoring such tests over video-links.

Antibodies against ribosomal phosphoprotein P0 of Plasmodium falciparum protect mice against challenge with Plasmodium yoelii

Antibodies against the Plasmodium falciparum P0 ribosomal phosphoprotein (PfP0) have been detected exclusively but extensively in malaria-immune persons. Polyclonal rabbit and mice sera were raised against two recombinant polypeptides of P. falciparum P0 protein, PfP0N and PfP0C, covering amino acids 17 to 61 and the remaining amino acids 61 to 316, respectively. Sera against both these domains detected a 35-kDa protein from Plasmodium yoelii subsp. yoelii, a rodent malarial parasite, and stained the surface of merozoites in immunofluorescence assays. Total immunoglobulin G (IgG) purified from rabbit and mouse anti-PfP0 sera by ammonium sulfate and DEAE-cellulose chromatography was used for passive transfer experiments in mice. Mice passively immunized with both anti-PfP0N and anti-PfP0C showed distinctly lower levels of parasitemia than control mice. With immunizations on days -1, 0, 1, 3, and 5, about 50% of both sets of mice receiving anti-PfP0N and anti-PfP0C cleared the lethal 17XL strain of P. yoelii and revived by day 25. All the control mice died by day 10. By extending the immunization schedule, the survival period of the mice could be extended for every mouse that received anti-PfP0 IgG. These data demonstrate the cross-protection of the anti-PfP0 IgG and establish parasite P0 protein as a target for invasion-blocking antibodies.

[Determination of the adenosine triphosphate in myocardial tissue by ion-pair reversed-phase high performance liquid chromatography]

ATP depletion is an important factor contributing to the incomplete recovery of ventricular function following ischemia and reperfusion. A simple and rapid method for determination of adenosine triphosphate(ATP) in myocardial tissue by RP-HPLC was developed. The chromatographic conditions were as follows: Spherisorb ODS2 column, V(40 mmol/L KH2PO4 and 5 mmol/L TBAP):V(methanol) = 74:26 (pH 6.2) mobile phase and UV detector at 259 nm. The ATP in myocardium was extracted with 0.4 mol/L HClO4. The calibration curve showed a good linearity in 5 mg/L-100 mg/L(r = 0.9998). The recovery ranged from 97.8% to 104.1%. The limit of detection was 2 mg/L. The verified results demonstrated that this method is precise, accurate and can be used for determination of ATP in myocardial tissue.

Pentacarbonyl(di-2-pyridylamine)tungsten(0)

In the title molecular complex, (I), the W atom is in an octahedral environment with four equatorial carbonyl ligands and a fifth in an axial position trans to the monodentate dipyridylamine ligand. The long dimension of this last bisects the angle between two of the equatorial carbonyl groups and while the non-bonded pyridyl N atom is directed away from the W atom, the bridging amine group is directed towards it. Thus, in addition to the N atom to which it is attached, the amino H has two nearest neighbour C atoms of equatorial carbonyl groups but does not participate in hydrogen bonding in any real or usual sense. The W-C bond distance for the axial carbonyl group is notably less than those of the equatorial groups.

[A foci of Schistosomiasis mekongi rediscovered in Northeast Cambodia: cultural perception of the illness; description and clinical observation of 20 severe cases]

In 1992 a foci of Schistosomiasis mekongi was rediscovered in the province of Kracheh in Northeast Cambodia. Severe clinical signs due to portal hypertension, which were frequently observed in this population, allowed the discovery of this 'forgotten' focus. Elements of the perception of the population and clinical observations of 20 severe cases due to S. mekongi infections are presented. Interviews with patients and villagers of the area of Kracheh showed severe psychosocial impact including fear from death, infirmity and invalidity. The symptoms of schistosomiasis were well known by the population and were reported to have increased in frequency in the last two decades. They have received traditional names and specific traditional treatment. The description of the clinical cases illustrates the severe pathology, which was observed in the hospital of Sambour, in the north of the province of Kracheh. It shows the pathogenic potential of S. mekongi in all age groups (from 7 to 58 years old): cachexia, hepatosplenomegaly, stunting and retardation of puberty, decompensation of portal hypertension with ascites and rupture of oesophagual varicies. The efficacy of the treatment in the severe stages varies. A follow-up after 30 months showed that 5 patients died, 5 initially improved but then relapsed, 3 remained unchanged and only 5 patients clearly improved. Two patients could not be followed-up. The clinical observations and interviews show severe pathology with impact at both individual and community level. The infection with S. mekongi is the main factor but additional concomitant factors are responsible for this fact. At a certain stage of the disease the prognosis for successful treatment is very low. These observations show the importance of the foci in the Province of Kracheh, Cambodia and underline the need for a long-term global intervention.

Predicting deterioration in previously healthy infants hospitalized with respiratory syncytial virus infection

OBJECTIVE

To estimate the incidence of clinical deterioration leading to intensive care unit transfer in previously healthy infants with respiratory syncytial virus (RSV) infection hospitalized on a general pediatric unit and, to assess the hypothesis that history, physical examination, oximetry, and chest radiographic findings at time of presentation can accurately identify these infants.

STUDY DESIGN

A virology database was used to identify and determine the disposition of all children </=1 year of age admitted to the Children's Hospital at Strong (CHaS) with RSV infection during the 1985 to 1994 respiratory seasons. Index patients were all previously healthy, full-term infants admitted initially to the general inpatient services at CHaS or Rochester General Hospital, a second University of Rochester teaching hospital, whose clinical deterioration led to transfer to the pediatric intensive care unit (PICU). These infants were matched retrospectively (for year and date of infection, sex, chronologic age, and race) with two hospitalized controls who did not require PICU transfer. Chest radiographic findings, respiratory rate (RR), O(2) saturation, and presence of wheezing at time of presentation to the emergency department (ED) were compared.

RESULTS

During the study years, 542 previously healthy, full-term infants were admitted to the general pediatric unit at CHaS with proven RSV infection. Ten (1.8%; 95% confidence interval, 0.9%, 3.4%) were transferred subsequently to the PICU, primarily for close monitoring of progressive respiratory distress. Data for these patients and 7 patients transferred from Rochester General Hospital to the PICU at the CHaS were compared with those for control patients. The mean RR in the ED (63 vs 50), and O(2) saturation in the ED (88% vs 93%) were modestly abnormal in cases compared with controls. Wheezing on examination at time of presentation and chest radiographic findings did not differ between the two groups. A RR >80 and an O(2) saturation <85% at time of presentation each had a specificity >97% for predicting subsequent deterioration. Each parameter, however, had a sensitivity </=30%.

CONCLUSION

Clinical deterioration requiring PICU admission is an uncommon occurrence in previously healthy infants admitted to a general pediatric inpatient unit with RSV infection. Extreme tachypnea and hypoxemia were both associated with subsequent deterioration; however, only a small proportion of patients who clinically deteriorated presented in this way. The clinical usefulness of these parameters, therefore, is limited. respiratory syncytial virus, deterioration, healthy infants, prediction.

Correlation between histochemically assessed fiber type distribution and isomyosin and myosin heavy chain content in porcine skeletal muscles

Highly sensitive enzyme assays developed to differentiate skeletal muscle fibers allow the recognition of three main fiber types: slow-twitch oxidative (SO), fast-twitch oxidative glycolytic (FOG), and fast-twitch glycolytic (FG). Myosin, the predominant contractile protein in mammalian skeletal muscle, can be separated based on the electrophoretic mobility under nondissociating conditions into SM2, SM1, IM, FM3, and FM2 isoforms, or under dissociating conditions into myosin heavy chain (MHC) I, IIb, IIx/d, and IIa. The purpose of the present study was to determine whether the histochemical method of differentiation of fiber types is consistent with the electrophoretically identified isomyosin and MHC isoforms. These comparisons were made using serratus ventralis (SV), gluteus medius (GM), and longissimus muscles (LM) from 13 pigs. Two calculation methods for the histochemical assessed fiber type distribution were adopted. The first method incorporated the number of fibers counted for each fiber type and calculated a percentage of the total fiber number (fiber number percentage: FNP). The second method expressed the cross-sectional area of each fiber type as a percentage of the total fiber area measured per muscle (fiber area percentage: FAP). Independent of the calculation methods, correlation analyses revealed in all muscles a strong relation between SO fibers, the slow isomyosin (SM1 and SM2), and MHCI, as well as between the FG fibers, the fast isomyosin (FM3 and FM2), and MHCIIx/b content (P<.05). There were no correlations between FOG fiber population assessed by histochemical analysis and intermediate isoform (IM) or MHCIIa content. The present results did not provide conclusive evidence as to which of the calculation methods (FNP or FAP) was more closely related to myosin composition of skeletal muscles. Despite some incompatibility between the methods, the present study shows that histochemical as well as electrophoretic analyses yielded important information about the composition of porcine skeletal muscle. The combination of the two methods may be essential to accurately characterize porcine skeletal muscles.

The effects of different resistance training protocols on muscular strength and endurance development in children

BACKGROUND

Previous research has shown that children can increase their muscular strength and muscular endurance as a result of regular participation in a progressive resistance training program. However, the most effective exercise prescription regarding the number of repetitions remains questionable.

OBJECTIVE

To compare the effects of a low repetition-heavy load resistance training program and a high repetition-moderate load resistance training program on the development of muscular strength and muscular endurance in children. Design. Prospective, controlled trial.

SETTING

Community-based youth fitness center.

SUBJECTS

Eleven girls and 32 boys between the ages of 5.2 and 11.8 years.

INTERVENTION

In twice-weekly sessions of resistance training for 8 weeks, children performed 1 set of 6 to 8 repetitions with a heavy load (n = 15) or 1 set of 13 to 15 repetitions with a moderate load (n = 16) on child-size exercise machines. Children in the control group (n = 12) did not resistance train. One repetition maximum (RM) strength and muscular endurance (repetitions performed posttraining with the pretraining 1-RM load) were determined on the leg extension and chest press exercises.

RESULTS

One RM leg extension strength significantly increased in both exercise groups compared with that in the control subjects. Increases of 31.0% and 40.9%, respectively, for the low repetition-heavy load and high repetition-moderate load groups were observed. Leg extension muscular endurance significantly increased in both exercise groups compared with that in the control subjects, although gains resulting from high repetition-moderate load training (13.1 +/- 6.2 repetitions) were significantly greater than those resulting from low repetition-heavy load training (8.7 +/- 2.9 repetitions). On the chest press exercise, only the high repetition-moderate load exercise group made gains in 1-RM strength (16.3%) and muscular endurance (5.2 +/- 3.6 repetitions) that were significantly greater than gains in the control subjects.

CONCLUSION

These findings support the concept that muscular strength and muscular endurance can be improved during the childhood years and favor the prescription of higher repetition-moderate load resistance training programs during the initial adaptation period.

The effect of external Ca2+ and Ca(2+)-channel modulators on red-light-induced swelling of protoplasts of Phaseolus radiatus L

Red-light-induced swelling of the protoplasts isolated from hypocotyl of etiolated mung bean (Phaseolus radiatus L.) was observed only when Ca2+ ions were present in the medium. The optimal CaCl2 concentration was 250 microM. Swelling response declined when Ca2+ was supplied into the medium after red light irradiation. The Ca(2+)-chelator EGTA eliminated the red-light-induced swelling and 45Ca2+ accumulation in the protoplasts. In contrast, A23187, a Ca(2+)-ionophore, could mimic the effect of red light in darkness. These results indicate that Ca2+ may play a role in light signal transduction. In addition, swelling response was prevented by TFP and CPZ (both are CaM antagonists), implying the involvement of CaM in red-light-induced and Ca(2+)-dependent protoplast swelling.

Persistence of human herpesvirus 6 according to site and variant: possible greater neurotropism of variant A

Little is known of the persistence and pathogenicity of human herpesvirus 6 (HHV-6) after primary infection, including the role of strain variant. Over 2 to 5 years, 2,716 children and 149 families were studied. Peripheral blood mononuclear cell (PBMC), saliva, and cerebrospinal fluid (CSF) specimens were examined for HHV-6 DNA and variant. Ninety-nine percent of isolates causing primary infection were HHV-6 variant B (HHV-6B), which predominated in 95%-98% of the variants persisting in PBMC and saliva specimens from children and adults. Of 668 CSF samples, 13% contained HHV-6 DNA; of 77 children examined after primary infection, 61% had HHV-6 DNA detected only in their CSF and 39% had HHV-6 DNA in both CSF and PBMCs. HHV-6 variant A (HHV-6A) was detected significantly (P = .0001) more frequently in CSF than in PBMCs or saliva. In children for whom HHV-6 was identified in both CSF and PBMCs, PBMCs contained only HHV-6B, while CSF contained HHV-6A or HHV-6B, not both. Thus, in patients with dual infection, only HHV-6A persisted in CSF, which suggests that HHV-6A has greater neurotropism. Findings for adults indicate that dual infection occurs; variant persistence is similar to that for children. The frequency of HHV-6A infection increased little with age, thereby indicating that HHV-6A infection remains uncommon into adulthood. This study suggests that HHV-6 variants have different immunobiologic courses and neurotropism.

[Quantitative determination of niphensamide by high performance liquid chromatography (HPLC)]

An HPLC method for the quantitative determination of Niphensamide in pesticide powder was developed. Column:Micropak-CH 5 microns (300 mm x 4.0 mm i.d.), mobile phase: CH3OH-H2O(1:1), detector: UV 254 nm, flow rate: 0.7 mL/min, column temperature: 25 degrees C. Under the above conditions, Niphensamide and other components were separated from each other. The method is simple, rapid, sensitive and accurate.

CD40 and CD40 ligand (CD154) are coexpressed on microvessels in vivo in human cardiac allograft rejection

BACKGROUND

CD40 is expressed by a wide variety of cells in the immune system, including endothelial cells. It binds to CD40 ligand ([CD40L] CD154), which was originally reported to be restricted in its expression to early-activated T cells. We report here the expression of CD40 and CD40L in human cardiac allografts.

METHODS

A total of 123 consecutive biopsies from 11 human cardiac allograft recipients were analyzed by immunohistochemistry for the expression of CD40 and CD40L. The expression of CD40L was also examined in vitro in homogeneous cultures of umbilical vein endothelial cells by reverse transcriptase-polymerase chain reaction and by flow cytometry.

RESULTS

CD40 was expressed at low levels, and CD40L was minimal or absent in histologically normal biopsies in the absence of CD3+ T-cell infiltrates. In rejection, the expression of CD40 increased on vascular endothelial cells and on graft-infiltrating leukocytes throughout biopsy specimens. Induced expression of CD40 was strongly associated with the presence of CD3+ T-cell infiltrates, acute rejection, and ischemic injury (P<0.05). CD40L was expressed in biopsies with rejection and was prominent on a subset of infiltrating leukocytes as well as on microvascular endothelial cells. In contrast to CD40, staining of endothelial CD40L was focal in most biopsies. Overall, the expression of CD40L correlated with the presence of CD3+ T-cell infiltrates and rejection (P<0.05), but not ischemic injury (P=0.9). To confirm that the endothelium can synthesize CD40L, we also evaluated the expression of endothelial CD40L in vitro. Cultured endothelial cells were found to express little constitutive CD40L that markedly increased after 24 hr of treatment with supernatants from phytohemagglutinin-activated peripheral blood mononuclear cells or by the cytokines tumor necrosis factor-alpha, interleukin-1a, interleukin-4, or interferon-gamma.

CONCLUSION

Both CD40 and CD40L are expressed in vivo on infiltrating leukocytes and on microvascular endothelium in human cardiac allograft rejection. We suggest that endothelial cell CD40 and CD40L play a role in human cell-mediated immune responses such as cardiac allograft rejection.

Enzyme-linked immunosorbent assay for detection of antibody to human herpesvirus 6

The results obtained with an enzyme-linked immunosorbent assay (ELISA) for detection of human herpesvirus 6 (HHV-6) immunoglobulin G using a single 1:100 dilution of serum correlated well with those found by an indirect fluorescence microscopic assay (IFA) (r = 0.71). Concordant results were found in all 7 paired serum samples obtained from patients with acute primary infections and in 37 of 41 (90.24%) single serum samples. Fourteen serum samples (25%) which yielded nonspecific results by IFA were evaluable by ELISA. In a serologic survey using the ELISA, a disproportionate number of 12-month-old infants had low difference-of-optical-density values, suggesting that maternal antibody might persist beyond a year of age. This finding and the rises in antibody to HHV-6 found in patients with primary cytomegalovirus infections might lead to overestimation of HHV-6 infection rates in young children in seroprevalence studies. Other herpesvirus infections produced lesser effects on anti-HHV-6.

Confirmatory factor analysis of the Wechsler Memory Scale-Revised in a sample of clients with alcohol dependency

Previous analyses of the Wechsler Memory Scale-Revised (WMS-R; Wechsler, 1987) have reported one-, two-, and three-factor solutions and raised questions about the validity of the visual memory subtests. These various findings may stem in part from different methods of analysis, and from the study of different participant samples. To address these issues, we analysed data from the WMS-R and a spatial maze test administered to 154 participants with a history of alcohol dependence. Results from confirmatory factor analysis supported the interpretation of three factors underlying the WMS-R subtests and the spatial maze score in this sample, namely, attention-concentration, immediate memory, and delayed recall. This result held despite the inclusion of the maze score which is a well-validated measure of visuo-spatial memory.

Simultaneous identification and quantitation of fluoxetine and its metabolite, norfluoxetine, in biological samples by GC-MS

A sensitive method for the quantitation of fluoxetine and norfluoxetine in biological samples was developed. Blood, urine, and tissue samples were alkalinized and extracted with N-butyl chloride. The extracts were derivatized with pentafluoropropionic anhydride before gas chromatography-mass spectrometry (GC-MS). Selected ions were monitored at m/z 117 and 294 for fluoxetine; m/z 117, 176, and 280 for norfluoxetine; and m/z 122 and 299 for the internal standard fluoxetine-d5. The within-run and between-run precision as well as recovery were determined for both analytes. The empirical limit of detection was determined to be 12.5 micrograms/L for both fluoxetine and norfluoxetine, whereas the empirical limit of quantitation was 25 micrograms/L for both drugs. Calibration curves were linear in the range of 50-1000 micrograms/L for both analytes. Some drugs that were known or suspected of interfering with high-performance liquid chromatography and GC methods for fluoxetine and norfluoxetine were tested for interference. This is the only reported method that combines the use of a deuterated internal standard, selected ion monitoring by GC-MS, and derivatization for the identification and quantitation of fluoxetine and norfluoxetine.

The GCMS analysis of tranylcypromine (Parnate) in a suspected overdose

A fatal overdose involving tranylcypromine (Parnate) where blood, urine and tissues were quantitated using a pentafluoroproprionic anhydride (PFPA) derivative and gas-chromatography/mass spectroscopy (GCMS). The samples were re-quantified over several weeks demonstrating a significant loss of drug in tissues but not blood or urine specimens. The urine was positive for methamphetamine which has been a suspected metabolite.

Interference with testing for lysergic acid diethylamide

We found a high rate (4.2%) of positive results for lysergic acid diethylamide (LSD) by Emit in 1898 urine samples that were submitted primarily from psychiatric patients for drugs-of-abuse (DOA) testing. Specimens that tested positive for LSD by Emit subsequently tested negative for LSD with two RIAs. Furthermore, LSD was not detected in randomly selected Emit-positive urine samples by gas chromatography-mass spectrometry. Normal urine samples tested positive for LSD by Emit when they were supplemented with therapeutic medications that were prescribed for patients with positive urine LSD results by Emit. These therapeutic drugs interfered specifically with the Emit assay for LSD, since other Emit DOA tests were not affected by these medications at the tested concentrations.

Comparison of analytical methods in the determination of two venlafaxine fatalities

Two venlafaxine (Effexor)-related deaths are reported with comparison of results from the analysis of specimens using capillary gas chromatography with a nitrogen-phosphorous detector (GC-NPD) and high-performance liquid chromatography (HPLC) using a UV-vis detector. Blood concentrations in Case 1 were 7.27 micrograms/mL venlafaxine and 5.03 micrograms/mL O-desmethylvenlafaxine, and Case 2 had 89.67 micrograms/mL venlafaxine with 3.44 micrograms/mL of the desmethyl metabolite. A comparison of analytical methods and specimen concentration is presented.

Chiropractic care for women with chronic pelvic pain: a prospective single-group intervention study

OBJECTIVE

To assess the role of chiropractic care for women with chronic pelvic pain (CPP) as a first step in designing a randomized clinical trial.

DESIGN

Prospective single-group intervention study.

SETTING

Chiropractic Research Center.

SUBJECTS

Nineteen volunteer female subjects meeting inclusion/exclusion criteria for chiropractic treatment of chronic pelvic pain.

INTERVENTIONS

Chiropractic treatment consisting of flexion/distraction and trigger point techniques administered by faculty clinician over a period of 6 wk.

MAIN OUTCOME MEASURES

Pain Disability Index (PDI) was the primary measure; secondary outcome measures were Visual Analog Scale for pain (VAS), RAND-36 Health Survey and Beck Depression Inventory (BDI). All were administered at baseline and at 6 wk.

RESULTS

Eighteen subjects completed the study, with an attrition rate of 5%. The mean improvement in the PDI score was 13.0 points (p = .001); in the VAS it was 4.0 cm (p = .001); and in the BDI it was 6.1 points (p < .001). All eight subscales of the RAND-36 Health Survey increased post-intervention, with the largest differences in role function limitations because of physical problems (45.8%), emotional problems (44.4%) and pain (40.6%).

CONCLUSION

The chiropractic treatment used in this study had positive short-term effects. These results will be used to design a randomized clinical trial to investigate the efficacy of chiropractic care in the treatment of CPP.

Traffic fatality related to the use of methylenedioxymethamphetamine

A recent traffic fatality has been attributed to the use of the drug methylenedioxymethamphetamine (MDMA). The deceased was a 29-year-old white male with no known history of drug abuse. Toxicological analysis detected MDMA and metabolite methylenedioxyamphetamine (MDA) in the blood, urine, and vitreous humor specimens submitted for analysis. The concentrations of MDMA in clotted blood, sodium fluoride-potassium oxalate anticoagulated blood, vitreous humor, and urine were 2.32 mg/L, 2.14 mg/L, 1.11 mg/L, and 118.8 mg/L, respectively. The concentrations of the metabolite MDA were less than 0.25 mg/L in blood and vitreous, and 3.86 mg/L in the urine.

Methamphetamine identification in four forensic cases

Specimens that tested positive for amphetamines by immunoassay were confirmed by mass spectrometry. The absence of detectable d-amphetamine (limit of detection at 50 ng/mL) with a positive methamphetamine prompted further testing by chiral derivatization. This data demonstrates that d-amphetamine need not be present in methamphetamine positive cases.

Problem-solving style, stress and psychological illness: development of a multifactorial measure

Problem-solving style has emerged in the literature as an important variable in the development and maintenance of affective disorders. Furthermore, the literature would suggest that it is related to other variables such as attributional style, achievement motivation and control in the mediation of the stress process. Research has been hampered and somewhat clouded by lack of clarity regarding the nature of the construct. It would appear to be a multidimensional construct, yet a suitable multifactorial measure is not available. The current paper reports on two studies (N = 408 and N = 611 respectively) which produced a 24-item six-factor measure. The factors were labelled helplessness, problem-solving control, creative problem-solving style, problem-solving confidence, avoidance style and approach style. The studies produced evidence that the utility of problem-solving style as an explanatory variable is enhanced when it is treated as a multidimensional construct. The factors appear to be differentially predictive of different affective states and clinical disorders. The data also support the 24-item measure as a useful, reliable and valid measure of problem-solving style.

Modulation of cranial bone healing with a heparin-like dextran derivative

Substituted dextran polymers have been shown to bind growth factors and protect them from enzymatic degradation. Using this information, other researchers have been able to use these substituted dextrans to enhance the healing of bone in an environment where bone would otherwise not regenerate. We used substituted dextran polymers to evaluate their ability to accelerate the healing of cranial bone in a rabbit model. We were able to document a more rapid rate of healing and demonstrate micrographic evidence to support that conclusion. Possible mechanisms are postulated.

The daily activities checklist:

This paper introduces the Daily Activities Checklist (DAC), an assessment developed for use with individuals with severe mental illness living in the community. The DAC establishes a baseline of engagement in self-care and instrumental activities of daily living and involves the consumer in the data gathering process. Preliminary information related to the feasibility and reliability of the measure suggests individuals with severe mental illness can accurately complete the assessment. The DAC also discrimated between individuals with severe mental illness that were working and those that were not.

In vivo photoinduction of metallothionein in human skin by ultraviolet irradiation

The aims of this study were to confirm and substantiate the in vivo cutaneous induction of metallothionein (MT) in human skin by UVR, which we have reported in brief previously, and to make a preliminary attempt to characterize the time course of this phenomenon. Buttock skin in 32 volunteers was irradiated with 2 MED of UVB and biopsies were taken at 24 h from matched non-irradiated and irradiated sites. In the kinetic study, skin biopsies from six volunteers were taken at 0, 2, 8, 24, and 48 h after 2 MED UVB irradiation. MT was immunolocalized in formalin-fixed, paraffin-embedded tissue with the monoclonal antibody E9 by an indirect immunoperoxidase method. Statistically significant differences between immunocytochemical scores were identified between non-irradiated (NI) and irradiated (I) skin within suprabasal keratinocytes (mean: NI = 1.2, I = 5.1; P = 0.01), superficial dermal fibroblasts (mean: NI = 2, I = 43; P < 0.001), mid-dermal fibroblasts (mean: NI = 0, I = 27; P < 0.001), and deep dermal fibroblasts (mean: NI = 0, I = 11; P < 0.001). In the kinetic study, no consistent rise in MT score with time was observed for the epidermal component. In dermal fibroblasts, however, the first statistically significant rise in immunocytochemically detectable MT was detected at 2 h and this was found to plateau beyond 8 h. These results confirm that ambient levels of UV irradiation are capable of inducing MT in human skin in vivo. Taken together with the relative rapidity of the response, this suggests a physiological photoprotective role for MT in human skin cells. The lack of a kinetic increase in epidermal MT may be due to high basal levels. Induction of MT in dermal fibroblasts may reflect the effects of a diffusible factor released from keratinocytes after UVR.

Partial characterization and assignment of the gene for protoporphyrinogen oxidase and variegate porphyria to human chromosome 1q23

Protoporphyrinogen oxidase (PPO) catalyses the conversion of protoporphyrinogen IX to protoporphyrin IX. Variegate porophyria (VP), a low-penetrant, autosomal dominate disorder characterized clinically by skin lesions and neurovisceral attacks, is caused by partial deficiency of this enzyme. Linkage between VP and the alpha-1-antitrypsin gene on chromosome 14 has been reported in VP families from South Africa, where the condition occurs at high frequency due to a founder effect. We have cloned a 4.5 kb genomic DNA fragment containing the entire coding sequence for human PPO. This clone has been used to localize the human PPO gene to chromosome 1q23 by fluorescence in situ hybridization analysis. The VP gene was mapped by linkage analysis, using microsatellite markers spanning the region 1q21-q25.1, in seven British VP families. Multipoint analysis between VP, SPTA1, APOA2 and D1S194 gave the maximum LOD score of 6.62 at APOA2, which has been physically mapped to 1q21-q23. Evidence for significant linkage between VP and markers in the alpha-1-antitrypsin region of chromosome 14 was not obtained. Our results assign the genes for PPO and VP to the same region chromosome 1, indicate that the PPO and VP loci are likely to be the same, and provide evidence against locus heterogeneity in VP.

Control of protein-ligand recognition using a stimuli-responsive polymer

Stimuli-responsive polymers exhibit reversible phase changes in response to changes in environmental factors such as pH or temperature. Conjugating such polymers to antibodies and proteins provides molecular systems for applications such as affinity separations, immunoassays and enzyme recovery and recycling. Here we show that conjugating a temperature-sensitive polymer to a genetically engineered site on a protein allows the protein's ligand binding affinity to be controlled. We synthesized a mutant of the protein streptavidin to enable site-specific conjugation of the responsive polymer near the protein's binding site. Normal binding of biotin to the modified protein occurs below 32 degrees C, whereas above this temperature the polymer collapses and blocks binding. The collapse of the polymer and thus the enabling and disabling of binding, is reversible. Such environmentally triggered control of binding may find many applications in biotechnology and biomedicine, such as the control of enzyme reaction rates and of biosensor activity, and the controlled release of drugs.

Inactivation of histone H1 kinase by Ca2+ in rabbit oocytes

The present study investigated the role of intracellular Ca2+ (Ca2+i) elevation on the inactivation of maturation promoting factor (MPF) in rabbit oocytes. The effects of the number of Ca2+ stimulations and of the amplitude of Ca2+i elevation on the profile of histone H1 kinase activity were determined. A Ca2+ stimulation consisted of transferring mature oocytes from culture medium to 0.3 M mannitol containing 0.1-1.0 mM CaCl2, and pulsing them at 1.25 kV/cm for 10 microseconds, or microinjecting 2-8 mM CaCl2 into the oocyte cytoplasm. The number of electrically-induced Ca2+ stimulations was varied, and amplitude of the Ca2+i rise was controlled by altering Ca2+ concentration in the pulsing medium or the injection pipette. Ca2+i concentration was determined with fura-2 dextran; oocytes were snap-frozen at indicated time points and assayed for H1 kinase activity. The activity was quantified by densitometry and expressed as a fraction of activity in nonstimulated oocytes. Electrically-mediated Ca2+i rises inactivated H1 kinase in a manner dependent on the number of Ca2+ stimulations. A single Ca2+ stimulation inactivated H1 kinase to 30-40% of its initial activity. However, H1 kinase inactivation was only transient, regardless of the amplitude of the electrically- or injection-mediated Ca2+i elevation. Increasing the number of Ca2+ stimulations helped to maintain H1 kinase activity at basal (pronuclear) levels. The results show the necessity of a threshold of Ca2+i concentration to trigger MPF inactivation, and suggest a role for the extended period of time over which Ca2+i oscillates at fertilization.

Explosion risk from swimming pool chlorinators and review of chlorine toxicity

Two patients were admitted to the hospital emergency room in respiratory distress after an accidental explosion involving chlorinating agents for the swimming pool. The two primary agents involved were calcium hypochlorite and trichloro-s-triazinetrione; both are commonly used chlorinating agents. These chemicals were tested in a bomb apparatus measuring temperature and gas production. Combining the two chlorinators at 2, 6, 12, or 18 g of each produced a progressive increase in gas production from 234 to 1422 mL. The temperature increased from 30 degrees C at 2 g to 63 degrees C at 18 g. The time to complete the reaction decreased from 6.2 minutes at 2 g to 3.8 minutes at 18 g. The third run at the 18 g level resulted in an explosion. The results indicate that gas generation is dependent on both products. The addition of organic material was abandoned because of the explosive nature of the reaction. The amount of calcium hypochlorite primarily determines the rate of reaction and heat generation. Appropriate emergency action and treatment for chlorine gas is discussed.

Neuroinvasion and persistence of human herpesvirus 6 in children

Human herpesvirus 6 (HHV-6) causes a febrile illness in children and has been implicated as a cause of encephalitis and recurrent seizures. Paired samples of cerebrospinal fluid (CSF) and peripheral blood mononuclear cells (PBMC) from 487 children were evaluated by nested polymerase chain reaction (PCR) for evidence of current or past infection with HHV-6. PBMC were also cultured for isolation of HHV-6. These data were correlated with the patients' clinical information. HHV-6 DNA was detected in 72 (14.8%) of 487 CSF samples. HHV-6 persistence was documented in 142 children by PCR detection of HHV-6 DNA in PBMC or CSF (or both) in the absence of primary HHV-6 infection; the central nervous system was the only site of HHV-6 DNA persistence in 28.9%. HHV-6 DNA can be detected in the CSF of children during and after primary infection, and the central nervous system may be the sole site of persistence.

Pharmacologic treatment of catheter-related thrombus in pediatrics

Venous and arterial catheters are being used with increasing frequency in pediatric populations. As part of the comprehensive management of these catheters, nurses need to be aware of the more common catheter-related thrombus problems. An understanding of pharmacologic treatment using Streptokinase and Urokinase for thrombus in central lines, hemodialysis grafts, and umbilical artery catheters can help nurses develop protocols to care for patients with these devices. The appropriate use of thrombolytic therapy can restore function to many catheters thereby saving the patient the cost and morbidity associated with removal and replacement of a dysfunctional catheter.

An assessment of serum and urine soluble interleukin-2 receptor concentrations during renal transplant rejection

During rejection, renal transplant recipients have increased concentrations of soluble interleukin-2 receptors (sIL-2R) in their serum and urine. However, the clinical application of this measurement in the diagnosis of rejection or the assessment of treatment efficacy is limited by the variance of the measurement in sample populations. We examined the serum and urine sIL-2R concentrations in 20 renal transplant recipients, 12 of whom experienced 13 episodes of allograft rejection. There was no statistical difference in the mean serum sIL-2R concentration at the time of rejection compared with the baseline value (2,817 +/- 801 v 1,943 +/- 255 U/mL). By contrast, the urinary excretion rate, expressed as units of sIL-2R per milligram creatinine, was 26.2 +/- 6.4 compared with 14.2 +/- 2.5 (P < 0.05). Furthermore, when urinary sIL-2R was expressed as a fractional excretion (FE), both the absolute measurement (4.4% +/- 1.7%) and the percent increase (+245%) at the time of rejection provided the greatest degree of discrimination of rejection from those values during allograft stability (1.2% +/- .2% and +2.5%, respectively; P < 0.005). We conclude that (1) serum and urine sIL-2R concentrations are affected by a number of factors during rejection; (2) FE calculations of sIL-2R improve discrimination of rejection from graft stability; and (3) serial measurement of sIL-2R excretion may be a useful adjunct to the diagnosis of rejection and, possibly, the subsequent assessment of response to immunotherapy.

Detection of latent variegate porphyria by fluorescence emission spectroscopy of plasma

The plasma of patients with overt variegate porphyria contains porphyrin with a fluorescence emission maximum at about 626 nm, which is diagnostic for the condition. We have evaluated qualitative fluorescence emission scanning of saline-diluted plasma as a method for the identification of asymptomatic carriers of the gene for variegate porphyria. Plasma from 36 unrelated patients with variegate porphyria, 136 of their asymptomatic first- and second-degree relatives aged 15 years or over, and 322 normal subjects was scanned. An emission maximum between 621 and 627 nm was observed in the 36 patients with variegate porphyria and 54 of their relatives, but not in any normal subject, nor in 56 patients with other types of porphyria. For the detection of asymptomatic adult carriers of the gene for variegate porphyria, fluorescence emission scanning of plasma appears to be 100% specific, with a sensitivity of 86% (95% confidence interval 71-98%). In contrast, the sensitivity of faecal porphyrin analysis as a test for adult gene carriers was 36%. These results suggest that fluorescence emission scanning of plasma should replace faecal porphyrin analysis as the test of first choice for this purpose.

Field trial of rhesus rotavirus or human-rhesus rotavirus reassortant vaccine of VP7 serotype 3 or 1 specificity in infants. The Elmwood, Panorama, and Westfall Pediatric Groups

Orally administered live rhesus monkey rotavirus vaccine (RRV, VP7 serotype 3) and human-rhesus reassortant rotavirus vaccine (DxRRV, VP7 serotype 1) were evaluated in a placebo-controlled field trial of 223 infants 2-4 months old. Both vaccines were mildly reactogenic but were generally well tolerated in the 10 days after vaccination. RRV and DxRRV were immunogenic, inducing serum antibody responses in 78% and 71% of the vaccines, respectively. Efficacy of RRV vaccine was 66% (P = .01) and of DxRRV vaccine 77% (P = .002) against rotavirus-associated illness in the first season after vaccination. Efficacy of RRV vaccine against rotavirus-associated illness over three rotavirus seasons was 51.2% (P = .045) and of DxRRV vaccine was 67.3% (P = .006). RRV vaccine provided heterotypic protection of 58.5% (P = .041) and DxRRV vaccine provided homotypic protection of 72.8% (P = .005) over three seasons against the predominant serotype 1 rotavirus.