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PubMed1986

Rate of clearance of intrathecal iopamidol in the dog.

The incidence of post-myelographic side-effects has been significantly reduced since the advent of the new generation of water-soluble, non-ionic, contrast media (CM). One of these CM, iopamidol, has recently been released for clinical intrathecal use in Australia. Clinical evaluations have shown iopamidol to give excellent diagnostic results. However, many adverse side-effects have been cited in the literature. Reactions to iopamidol following myelography are thought to be due to the lack of a physiologic barrier between the extracellular fluid of the brain parenchyma and the CSF, thereby allowing CM to penetrate the brain parenchyma tissue, following subarachnoid injection. This study investigates the rate of clearance of intrathecal iopamidol from the brain in dogs by performing coronal CT scans at intervals over a 48 h, post-injection period. Analysis of similar regions of interest (ROI) for each time period indicate that iopamidol can be detected in canine brains for at least 48 h following intrathecal injection (P less than 0.05). Furthermore, the disappearance of iopamidol from the brain parenchyma is approximately logarithmic in form, with a half-life of approximately 22 h.

Animals↗
PubMed2005

Radon anomalies preceding earthquakes which occurred in the UK, in summer and autumn 2002.

During the course of an investigation into domestic radon levels in Northamptonshire, two hourly sampling real-time radon detectors were operated simultaneously in separate locations 2.25 km apart in Northampton, in the English East Midlands, for a 25-week period. This period of operation encompassed the period in September 2002 during which the Dudley earthquake (magnitude - 5.0) and smaller aftershocks occurred in the English West Midlands, UK. We report herein our observations regarding the occurrence of simultaneous short-period radon anomalies and their timing in relation to the Dudley, and other, earthquakes which occurred during the monitoring period. Analysis of the radon time-series reveals a short period when the two time-series displayed simultaneous in-phase short-term (6-9 h) radon anomalies prior to the main Dudley earthquake. Subsequent investigation revealed that a similar period occurred prior to another smaller but recorded earthquake in the English Channel.

Air↗
PubMed2002

Changes in the incidence and predictors of wasting syndrome related to human immunodeficiency virus infection, 1987-1999.

The authors examined the impact of potent antiretroviral therapy (ART) on the diagnosis of wasting syndrome in the Multicenter AIDS Cohort Study. Study time was divided into the periods 1988-1990, 1991-1993, 1994-1995, and 1996-1999 to correspond to different treatment eras. The proportion of acquired immunodeficiency syndrome diagnoses in which wasting was present increased from 5% in 1988-1990 to 7.1% in 1991-1993, 7.7% in 1994-1995, and 18.9% in 1996-1999. The incidence of wasting per 1,000 person-years increased from 7.5 in 1988-1990 to 14.4 in 1991-1993 and 22.1 in 1994-1995; it decreased to 13.4 in 1996-1999. Fewer patients with wasting had low hemoglobin and hematocrit levels and reported oral thrush in 1996-1999 than in any other period. Analysis of change in body mass index (weight (kg)/height (m)(2)) after wasting showed a faster return to prewasting levels in 1994-1995 and 1996-1999 than in earlier periods. Case-control analysis showed that wasting prior to 1996 was weakly associated with fatigue (p = 0.10), low hemoglobin (p = 0.11), and CD4-positive T-lymphocyte count (p = 0.04). During 1996-1999, wasting was weakly associated with diarrhea (p = 0.05) and potent ART (p = 0.097). Predictors of wasting have changed with potent ART. Further research is needed to determine whether lipodystrophy may be misdiagnosed as wasting syndrome.

Anemia↗
PubMed1993

Structures of sulfated oligosaccharides in human trachea mucin glycoproteins.

The structures of high molecular weight sulfated oligosaccharide chains in mucins purified from the sputum of a patient with cystic fibrosis and blood group H determinant were established. Reduced oligosaccharides released by treatment with alkaline borohydride were separated by ion exchange chromatography on DEAE-Agarose and a fraction containing multisulfated chains was further purified by lectin affinity chromatography to completely remove small amounts of sialylated chains. A major sulfated oligosaccharide fraction containing chains with an average of 160 to 200 sugar residues was isolated by gel filtration on BioGel P-10 columns and individual subfractions were characterized by methylation analysis, periodate oxidation and sequential glycosidase digestion before and after desulfation. Carbohydrate analysis yielded Fuc, Gal and GldNAc in a ratio of 1:2:2.1 and only one galactosaminitol residue for every 160- to 200 sugar residues. The average molecular weight of oligosaccharide chains in these fractions was between 27,000 and 40,000 daltons. Structural analysis showed that these high molecular weight chains contained varying amounts of the repeating unit shown in the following oligosaccharide. Only one in about every 10 repeating units contained sulfate esters. Several shorter chains which contain 2 to 3 sulfate esters were also isolated from this multisulfated oligosaccharide fraction. The structures proposed for these oligosaccharides indicate that they are lower molecular weight chains with the same general structure as those found in the high molecular weight sulfated oligosaccharides. Taken collectively, the results of these studies show that a major sulfated oligosaccharide fraction in respiratory mucin purified from the mucus of patients with cystic fibrosis contains high molecular weight branched chains that consist of a repeating oligosaccharide sequence with sulfate linked to the 6 positions of galactose and possibly GlcNAc residues in the side chains.

Carbohydrate Sequence↗
PubMed2005

SEN virus has an adverse effect on the survival of HIV-positive patients.

BACKGROUND: Patients infected with HIV are often coinfected with other viruses. OBJECTIVE: To investigate the effect of SEN virus (SENV) strains D and H on mortality in HIV-positive patients. METHODS: A total of 217 HIV-positive patients were analysed retrospectively after first presentation and blood sampling (January 1997 to July 1997) and the effect of coinfection with SENV-D and SENV-H on survival was examined. Analysis periods were the time from blood sampling to the end of follow-up, and the time from diagnosis of HIV infection to the end of study follow-up. SENV-H DNA was measured quantitatively. Prevalences of SENV-D and SENV-H were compared with those in 112 healthy blood donors. RESULTS: SENV prevalence was significantly higher in HIV-positive patients than in controls (56/217 and 12/112, respectively; P < 0.001). SENV positivity had no influence on survival, but a significant negative influence of SENV-H on survival was observed when SENV-H DNA was > 530 copies/ml, which was the mean SENV-H DNA level found in HIV-negative controls. This adverse effect was found for both studied time periods in a Kaplan-Meier analyses. A multivariate Cox regression analysis, including CD4 cell count, Centers for Disease Control and Prevention stage, age, sex, HIV RNA, highly active antiretroviral therapy and hepatitis C virus status, revealed that a high SENV DNA level was an independent risk factor or indicator for adverse disease outcome. CONCLUSION: SENV infection is common in HIV-positive patients. High SENV-H DNA levels were predictive for poor survival in HIV-positive patients.

Adult↗
PubMed1989

[Ecologic dynamics of infectious diseases. II. Periodic recurrence of epidemics].

The incidence of hepatitis, mumps, poliomyelitis, scarlet fever, pertussis and measles from 1954 to 1984 was studied from the annual records of infectious diseases. Fluctuations were evaluated by Fourier analysis. Periodic recurrency was detected for poliomyelitis, scarlet fever, pertussis and measles and was likely for mumps. The asynchronic fluctuation of the proportion of cases and susceptible individuals is considered to be the origin of this phenomenon. Observed fluctuations corresponded to those predicted by the models.

Chile↗
PubMed1991

Autopsy-verified pulmonary embolism in a surgical department: analysis of the period from 1951 to 1988.

A retrospective analysis was undertaken of all surgical patients in Malmö, Sweden, during the period from 1951 to 1988 in whom pulmonary emboli were found at autopsy. The analysis included a comparison with the earlier analysed and reported time period from 1951 to 1980. A continued high frequency of pulmonary embolism at autopsy was seen during the 1980s (20.3 per cent of deaths, 31.7 per cent of autopsies). Of the 391 autopsy-verified pulmonary emboli found between 1981 and 1988, 113 (28.9 per cent) were considered fatal, 104 (26.6 per cent) contributed to death and 174 (44.5 per cent) were incidental. Few patients had symptomatic deep vein thrombosis or pulmonary embolism before death. The overall frequency of major pulmonary embolism in surgical patients remained unchanged (0.3 per cent). The frequency of major postoperative pulmonary embolism showed an increase during the 1950s and 1960s (maximum 0.4 per cent) but a decrease in the last 5-year period of the 1970s (0.3 per cent), which has earlier been reported upon. This decrease continued during the 1980s (0.2 per cent) (P less than 0.05). An increase was found in the number of patients operated on who had autopsy-proven pulmonary embolism and who received thromboprophylaxis. Pulmonary embolism continues to be a major cause of death in surgical patients; however, postoperative major pulmonary embolism has shown a reduction in the last 15-year period.

Adult↗
PubMed1980

Optional production and utilization of polysaccharide by Aeromonas hydrophila.

Glucans from the fish pathogen Aeromonas hydrophila have been extracted and purified by a method utilizing phenol/water followed by sodium deoxycholate rather than the traditional sodium hydroxide extraction. Presence of substantial amounts of these glucans was shown to be dependant on whether or not the substrate contained dextrose, a point which had import because of the low carbohydrate environment in which this species must survive and multiply. These glucans, produced in the log phase, were utilized during the growth period. The structures of the two purified glucans were examined by methylation analysis, periodate oxidation, and enzymatic degradation. The results indicated that A. hydrophila under low-carbohydrate growth conditions produced two similar but distinguishable alpha 1 leads to 4 linked glucans substituted alpha 1 leads to 6 by single monosaccharide residues or short chains to give an amylopectinglucogen type of polysaccharide.

Aeromonas↗
PubMed2002

Clinical evaluation of oxidative stress and myocardial reperfusion injury in pediatric cardiac surgery.

BACKGROUND: To evaluate oxidative stress and myocardial damage after aortic crossclamping release (ACCR) during cardio pulmonary bypass (CPB) in children two parameters were investigated: total glutathione (GSH) and its oxidoreductive reactions (GSH/GSSG) as expression of oxidative stress, and plasmatic turnover of myocardial taurine (TAU) as expression of cell damage. METHODS: The study was divided in two periods: 1) first period: analysis of oxidative stress and myocardial damage in 18 children. 2) Second period: evaluation of myocardial cell protection by controlled anterograde low oxygen warm reperfusion (ALOWR) before declamping. Twenty-one children were divided in two groups: not receiving (Group 1, 9 patients) and receiving (Group 2, 12 patients) ALOWR. RESULTS: In the first period GSH values increased significantly after onset of mechanical ventilation (MV) in vein, after CPB start in artery and after ACCR in coronary sinus. Moreover TAU turnover in aortic and coronary sinus blood increased significantly after ACCR. In the second period, Group 2 showed a lower oxidative stress after ACCR, while no differences were observed in TAU turnover. CONCLUSIONS: 1) Assessment of TAU and GSH levels can be considered a good method to clinically evaluate myocardial injury during cardiac surgery. 2) MV and CPB can induce oxidative stress before aortic clamping and can decrease the physiologic scavengers. Therefore, to prevent that depletion, the strategy of these techniques must be adapted to the patient and to his cardiac disease. 3) Intramyocardial TAU turnover is not significantly modified by the reperfusion technique. 4) ALOWR can reduce myocardial oxidative stress and can improve heart recovery after the cardioplegic arrest.

Cardiopulmonary Bypass↗
PubMed2004

[Human cystic hydatidosis in Italy: a public health emergency? Past to present].

Starting from 1991 the Central Office of Statistics ISTAT, according to changed regulations on notification of infective diseases, stopped reporting official national data on human hydatidosis. On the other hand until then notified data, concerning only about a hundred cases per year in mean during the last decades and just 36 in 1991, appeared unreliable, suggesting a diffusion far from the actual. Owing to specific studies on different research groups it is possible to try to describe a not exhaustive but indicative pattern of trend of human hydatidosis in Italy. More recent publications regarding different regions report an annual mean incidence rate of surgical cases of 9.77/100,000 inhabitants in Sardinia, of 1.57 in Emilia Romagna, of 2.30 in Sicily and of 2.33 in Apulia, the latter encompassing only hepatic cysts treated in the region, irrespective of residence of subjects. A comparison with previous studies regarding the period between 1948-1952 and 1980-84 respectively, indicates an increase in the more recent surveys. However, as even underlined by Authors, former surveys were not all-embracing (for example not including patients from private Clinics etc). On the other hand during time, improvements in surgical as well in anaesthesiological skills have made surgery possible in patients previously inoperable, and particularly in old subjects. Conversely, at present, availability of alternative therapies such as chemotherapy, PAIR or modified PAIR-based techniques may allow cases to avoide surgical surveys. However, actual parasite burden in humans may be estimated by assessing the trend of likely young cysts, as due to recent infections. Rate of pulmonary cysts, that are sure to be young, was of 48.6%/100,000 inhab. in 1952 in Italy, then falling to 18.2 in 1980-84 in the 9 considered regions, to 12.7 in Sicily (1989-91), 6.5 in Emilia-Romagna (1989-93) and 15.7 in Sardinia (1990-95). Another "class" of surely young cysts regards all cysts in young age group that necessarily have been recently infected. Ratio of infection rates in the old/young people was around 1 in 1941-52 but was exceeding 3 in 1980-84. In addition available data from more recent surveys indicate that ratio is at present still relatively low in Sardinia (3.9), where sheep-breeding is widespread, and dog-livestock-man interaction is most likely to exist, and conversely is very high in Emilia-Romagna (5.75) where pastoral economy is not prevalent (just 92,000 sheep). Actual trend both parasitological and in terms of public health would ameliorate if studies were provided with long temporary series. In Sardinia all hydatid cases surgically treated from 1969 to 1995 have been registered and analysed with a standardized methodology. During the considered period incidence appears nearly unvaried (16.9 in 1969 vs 15.8 in 1985), with a fall only for the last 5 years (9.1 in 1995), and with an increase regarding 1984-88 period. Analysis according to cyst localization strongly suggests that fall in the last period is only weakly related to hepatic cysts, that conversely are near completely responsible of rise in 1984-88. On the contrary for pulmonary cysts, i.e. young cysts, a slow but continuous and significant decrease (from 6.5 in 1969 to 1.4 in 1995) is evident. In the same way the above- mentioned old/young ratio rises from 1.7 (1969-79) to 3.9 (1990-95). On the whole analysed data suggest that although parasitic burden, strong in central-south Italy for decades, is now slow lowering due to structural changes and improvements in general conditions of life rather to specific preventive actions, human hydatidosis still represents a public health problem that will continue in the future as, because of latency, incidence rates will stay long relevant.

Adult↗
PubMed1978

Drug use and employment patterns before and during treatment.

This paper was initiated to study the effect of outcome measures as they relate to indication of treatment success. Results have shown that after the third month in treatment, drug use decreases very little. Time in treatment in significantly related to urin-analysis results during the first 3 months; that is, those clients who were to remain in treatment for longer periods were those whose average opiate use during the first 3 months were lowest. We also found that no relationship exists between pretreatment opiate use and opiate use during any evaluation time period. Analysis of employment change rate for a 1-year's period indicate that those employed at intake remain employed and those unemployed remain so. Change in opiate use during any evaluation period had no influence whatsoever on employment.

Amphetamines↗
PubMed1992

Periodicity coding in the auditory system.

Periodic envelope fluctuations are a common feature of acoustic communication signals, and as a result of physical constraints, many natural, nonliving sound sources also produce periodic waveforms. In human speech and music, for example, periodic sounds are abundant and reach a high degree of complexity. Under noisy conditions these amplitude fluctuations may be reliable indicators of a common sound source responsible for the activation of different frequency channels of the basilar membrane. To make use of this information, a central periodicity analysis is necessary in addition to the peripheral frequency analysis. The present review summarizes our present knowledge about representation and processing of periodic signals, from the cochlea to the cortex in mammals, and in homologous or analogous anatomical structures as far as these exist and have been investigated in other animals. The first sections describe important physical and perceptual attributes of periodic signals, and the last sections address some theoretical issues.

Acoustic Stimulation↗
PubMed2006

Profiles of pain after day surgery: patients' experiences of three different operation types.

AIM: The aim of this paper is to examine the pain profile of three types of day surgery operation and undertake a comparative analysis of the intensity and duration of pain over a consecutive 4-day period. BACKGROUND: Although studies on pain after day surgery have figured prominently, evidence is limited as to what intensity and duration of pain should be regarded as unacceptable, and how it varies for different operation types. METHODS: A prospective postal survey (n = 785) was undertaken during a 12-month period in 1998/1999 involving three day surgery units in three different areas in England and Wales and based on three commonly performed operation types: hernia repair, varicose vein surgery and laparoscopic sterilization. A visual analogue scale was used to measure the intensity of pain experienced over a 4-day consecutive time period. Analysis of variance was used to explore statistically significant differences between levels of pain for the operation types. RESULTS: On the day of surgery and even on the third postoperative day, high levels of severe pain (>50 mm on a Visual Analogue Scale) were experienced. Pain levels differed across different operation types. On the day of surgery, more patients undergoing laparoscopic sterilization experienced severe pain. By the third postoperative day, more of those who had been operated on for hernia repair, followed by varicose vein surgery and laparoscopic sterilization, continued to experience severe pain. CONCLUSION: A large number of patients experienced severe levels of pain after day surgery. This could have resulted from a lack of knowledge about the assessment and management of pain, in which nurses play an important role. This study has highlighted that different pain trajectories are associated with different operation types, and this has important implications for the preoperative and postoperative preparation of day surgery patients as well as the role of nurses in the overall success of the day surgery process.

Adolescent↗
PubMed2003

Development and application of a robust speciation method for determination of six arsenic compounds present in human urine.

Six arsenic species [arsenate, arsenite, arsenocholine, arsenobetaine, monomethyl arsonic acid, and dimethyl arsinic acid] present in human urine were determined using ion-exchange chromatography combined with inductively coupled plasma mass spectrometry (IC-ICP-MS). Baseline separation was achieved for all six species as well as for the internal standard (potassium hexahydroxy antimonate V) in a single chromatographic run of less than 30 min, using an ammonium carbonate buffer gradient (between 10 and 50 mM) at ambient temperature, in conjunction with cation- and anion-exchange columns in series. The performance of the method was evaluated with respect to linearity, precision, accuracy, and detection limits. This method was applied to determine the concentration of these six arsenic species in human urine samples (n = 251) collected from a population-based exposure assessment survey. Method precision was demonstrated by the analysis of duplicate samples that were prepared over a 2-year analysis period. Total arsenic was also determined for the urine samples using flow injection analysis coupled to ICP-MS. The summed concentration of the arsenic species was compared with the measured arsenic total to demonstrate mass balance.

Arsenic↗
PubMedDate not supplied

Seasonal variation in onset of acute appendicitis.

PURPOSE: Several acute diseases exhibit a circannual pattern. The present study was aimed to verify the possible existence of a seasonal variability in the onset of acute appendicitis (AA). PATIENTS AND METHODS: All cases of AA diagnosed at the St Anna Hospital of Ferrara, Italy, from 1998 to 2004, were considered. The total sample was divided into subgroups by gender, age (< or = 19 and > or = 20 years), and ICD9-CM code. For statistical analysis, the distribution of symptom onset was tested for uniformity by the chi2 test for goodness of fit, and chronobiological analysis was performed by applying partial Fourier series. RESULTS: In the 7-year period analysis, 1331 consecutive cases of AA (673 males) were observed. The analysis showed, for total population, a seasonal variation with a peak in summer and a nadir in spring. Subjects < or = 19 years (n = 654) showed a higher frequency of events in winter (winter = 191 cases, 29.2%; spring = 154 cases, 23.5%, summer = 142 cases, 21.7%, autumn = 167 cases, 25.5%, chi2 = 8.07 p = 0.046), whereas subjects > or = 20 years (n = 677) showed a higher frequency in summer (winter = 150, 22.2%, spring = 151, 22.3%, summer = 214, 31.6%, autumn = 162, 23.9%, chi2 = 16.33 p = 0.001; difference between the two groups: chi2: 19.2, p < 0.001). Cases of AA with peritonitis (ICD-9 540.0, n = 90), were more frequent in summer (winter = 18, 20%, spring = 19, 21.17%, summer = 38, 42.2%, autumn = 15, 16.7%, chi2 = 14.22, p = 0.002), and chronobiological analysis found a statistically significant peak of higher incidence in July (PR 68.2, 95%CL: May-September, p = 0.006). CONCLUSIONS: The existence of a seasonal pattern in the onset of AA is confirmed, with differences in relation to age.

Acute Disease↗
PubMed1999

Reversed-phase ion-pair HPLC method for the direct analysis of 1-OH midazolam glucuronide in human serum.

In recent years, it has become clear that the presence of high concentrations of 1-OH midazolam glucuronide is probably the cause of unexplained prolonged midazolam comas in patients with poor renal function. Until recently, only indirect methods for the analysis of this glucuronide were known, which had several disadvantages, such as a long analysis period (>6 hours). This article describes the validation of a method for the direct analysis of this compound in human serum, using reversed-phase ion-pair high-performance liquid chromatography (HPLC) in combination with solid phase extraction. The intraday and interday coefficients of variation have values below 6% for different possible serum concentrations. The limit of quantification (0.1 mg/L) is much lower than concentrations found in patients with a coma caused by the accumulation of 1-OH midazolam glucuronide. Recovery of 1-OH midazolam glucuronide is almost 100% at three different serum concentrations. Linearity is confirmed for normal serum levels (<1 mg/L) and for serum levels that might occur in patients with impaired renal function (<20 mg/L). Detection is performed at 254 nm with a diode array detector, which can also be used to check the peak purity in case of unexpected impurities.

Calibration↗
PubMedDate not supplied

[Detection of a steady increase in endonuclease activity in dog liver cell nuclei after long term arterial hypotension and in post-resuscitation period].

Presence of Ca2+, Mg(2+)-dependent endonuclease activity was found in dog liver cell nuclei. Specific characteristics of chromatin autolysis were also studied in liver cell nuclei after 2-4 hrs long arterial hypotension as compared with that within the later restoration period 1-3 months. The rate of DNA acid-soluble fraction accumulation correlated directly with the arterial hypotension duration. Quantitative evaluation of the liver tissue Ca2+, Mg(2+)-dependent endonuclease activity was undertaken under conditions of hemorrhagic shock. The enzymatic activity was not normalized both after death and in the postresuscitation period. Analysis of the chromatin autolysis and of alterations in the enzymatic activity during postresuscitation period enabled to suggest that the isozyme spectrum of Ca2+, Mg(2+)-dependent endonuclease was altered.

Animals↗
PubMed1988

Effect of infusion pump fill-stroke flow interruption on response to sodium nitroprusside in surgical patients.

The influence of the piston-cassette pump fill stroke on the pharmacodynamic response to sodium nitroprusside was evaluated prospectively in 10 adult patients in the surgical intensive-care unit. Simultaneous analog recordings of blood pressure and fill stroke were made over three complete pump fill cycles in each patient. Sodium nitroprusside flow rates and concentrations were recorded throughout the data-collection period. Analysis was based on the maximum pressure obtained during the two-minute baseline period before a fill stroke (Pmax baseline), the pressure at the initiation of the fill stroke (P initial), and the maximum pressure obtained during the two-minute period after the fill stroke (Pmax postfill). The maximum systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean blood pressure (MBP) during the baseline and post-fill-stroke periods were significantly different. The mean (+/- S.D.) variability in pressure between the time periods Pmax baseline and Pmax postfill was 3.9 +/- 5.8 mm Hg for SBP (range, -8 to +16), 3.5 +/- 5.7 mm Hg for DBP (range, -7 to +13), and 3.6 +/- 5.6 mm Hg for MBP (range, -7 to +14). The likelihood of a pharmacodynamic change was inconsistent both between and within patients. Within patients the difference between cycles for the variability between time periods ranged from a minimum of 2 mm Hg to a maximum of 16 mm Hg for SBP, 2 mm Hg to 17 mm Hg for DBP, and 1 mm Hg to 17 mm Hg for MBP. The variability within the baseline period (Pmax baseline - P initial) in SBP was significantly greater than the variability between the time periods, while the differences for DBP and MBP were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗