Detection of parvovirus B19 in macerated fetal tissue using in situ hybridisation

AIMS

To compare the application of a non-radioactive in situ hybridisation (ISH) technique with an immunocytochemical technique for the detection of human parvovirus B19 in formalin fixed, paraffin wax embedded sections of macerated fetal tissue.

METHODS

Archived samples of liver, lung or kidney from 19 human fetuses were investigated for parvovirus B19 using a full length digoxigenin labelled DNA probe of 5.5 kb; bound probe was detected using an anti-digoxigenin (alkaline phosphatase) conjugate and visualised using NBT/BCIP. Immunocytochemical detection of parvovirus B19 was performed using a monoclonal mouse antiparvovirus B19 antiserum, with a streptavidin-biotin complex (horse radish peroxidase) method. Cases were selected to provide a range of diagnostic certainty and a range of degrees of macerative degeneration.

RESULTS

Parvovirus B19 was found in 15 of 19 cases using the B19 ISH technique compared with 8 of 19 cases using the immunocytochemical technique. The four negative cases were all controls known to be parvovirus B19 free. All ISH positive cases showed excellent staining with low background regardless of extent of maceration and tissue type. In comparison, sections stained by the immunocytochemical method showed considerable non-specific immunoreactivity in many cases, particularly with severe maceration. Kidney and lung tissues gave the cleanest results.

CONCLUSIONS

ISH is more effective than the immunocytochemical technique for the detection of human parvovirus B19 in macerated fetal tissue. The lack of detectable background staining with the ISH technique led to easier interpretation suggesting that this technique should be the method of choice for the investigation of parvovirus B19 in macerated postmortem tissues.

Pharmacokinetics of dexamethasone and its relationship to dexamethasone suppression test outcome in depressed patients and healthy control subjects

The pharmacokinetics of dexamethasone (DEX) were studied in 9 drug-free melancholically depressed patients and 10 healthy control subjects matched by sex and age. Each subject received 1 mg of DEX administered orally and by the (i.v.) route at 11:00 PM and serial blood samples were collected over the next 17 hours until 4:00 PM. There were no significant differences between the diagnostic groups and DEX bioavailability, peak plasma level, time to maximum concentration, or in elimination half-life after oral administration. Bioavailability estimates indicated that DEX absorption was incomplete and variable mean = 61%, SD = 14) in controls as well as depressed patients. In both groups there was a wide interindividual variability in plasma DEX levels following both oral and i.v. routes of administration. This variability could not be reliably predicted by differences in age, sex, or weight between subjects. The factors that accounted for most the variability in 4:00 PM plasma DEX levels after oral administration were clearance, bioavailability, and time to reach maximum concentration. Plasma DEX levels were lower in 3 depressed nonsuppressors compared to 3 matched controls who suppressed. No single pharmacokinetic factor was shown to be responsible for the lower DEX levels in the depressed nonsuppressors. These results indicate that plasma DEX levels need to be measured in each individual during the DST procedure so that this information may be taken into consideration when interpreting DST results.

Tryptase and IgE concentrations in the respiratory tract of infants with acute bronchiolitis

It has been proposed that a specific IgE response contributes to the immunopathology of acute respiratory syncytial virus (RSV) bronchiolitis but previous work has been difficult to replicate. Indirect evidence that might support this contention was sought by measuring total IgE concentrations in bronchoalveolar lavage (BAL) samples obtained from intubated infants and by attempting to detect mRNA for IgE in cells obtained from both the upper and lower respiratory tract. Evidence of significant mast cell activation was sought by measuring tryptase concentrations in BAL fluid and serum. Detectable concentrations of IgE were found in two of seven BAL samples obtained more than five days after intubation and mRNA for IgE was demonstrated in three of six BAL samples and three of six samples obtained from the upper respiratory tract. Tryptase was detectable in 11 of 12 BAL samples with the two highest values detected on day 1. These values were raised compared with control samples but were not such to suggest that mast cell degranulation is the major contributor to the inflammatory process. These results suggest that IgE may be produced in the airways of infants in response to RSV infection. The relationships between IgE production, RSV infection, and symptoms of acute bronchiolitis remain obscure.

The anaphylaxis hypothesis of sudden infant death syndrome (SIDS): mast cell degranulation in cot death revealed by elevated concentrations of tryptase in serum

A series of cases of sudden unexpected post-neonatal deaths from two centres in the UK have been investigated for evidence of mast cell activation using the biochemical markers tryptase and 9 alpha,11 beta-PGF2. Tryptase was selected as a possible marker because it is a component of mast cell secretory granules and, unlike histamine, it is not released from basophils. The prostaglandin 9 alpha,11 beta-PGF2 is an initial and pharmacologically active metabolite of PGD2, the major mast cell-derived cyclooxygenase product. This prostaglandin was chosen to serve as a marker of newly generated mediator release. In the study, unexplained infant deaths were associated with a higher concentration of tryptase in serum compared with cases of unexpected, but subsequently explained death. However, 9 alpha,11 beta-PGF2 was found to be an unsuitable post mortem marker in this situation. These results provide direct evidence that mast cell degranulation, possibly as a result of anaphylaxis, may be occurring around the time of death in some cases of cot death.

The effect of local hyperthermia on allergen-induced nasal congestion and mediator release

BACKGROUND

Local hyperthermia reduces mast cell degranulation, the severity of acute lung injury, and exercise-induced asthma and decreases symptoms of rhinitis. We have investigated the effect of local hyperthermia on mast cell degranulation and symptom generation in allergic rhinitis to assess its effect and mechanism of action within the nose.

METHODS

In a randomized, double-blind, placebo-controlled, crossover study, 10 subjects with rhinitis were treated for 30 minutes with local hyperthermia or placebo, which was followed 30 minutes later by nasal allergen challenge. During the first two visits nasal lavages were performed to assess vascular leakage and mediator release. During the last two visits nasal airway resistance, the number of sneezes, and mucus secretion were monitored.

RESULTS

Local hyperthermia significantly reduced both nasal airway resistance (p < 0.05) and vascular leakage (p < 0.02) but had no significant effect on the number of sneezes, on mucus secretion, or on tryptase release.

CONCLUSION

Local hyperthermia reduces allergen-provoked nasal blockage and vascular leakage but has no effect on sneezing, rhinorrhea, or tryptase release. Nasal blockage occurs predominantly via newly formed lipid mediators and kinins, whereas sneezing and rhinorrhea occur predominantly via preformed mediators. We propose that local hyperthermia inhibits newly formed mediator production or release or reduces the sensitivity of the vasculature to inflammatory mediators in general. Further investigation into the mechanisms and potential uses of local hyperthermia is warranted.

Circulating histamine and eosinophil cationic protein levels in nocturnal asthma

1. To investigate the role of mast cells and eosinophils in the pathogenesis of nocturnal asthma, the plasma methylhistamine concentration, serum eosinophil cationic protein level and peak expiratory flow rate were measured 2-hourly for 24 h in 10 patients with nocturnal asthma and in 10 healthy control subjects. Nocturnal asthma was defined as at least one nocturnal awakening per week due to cough, wheeze or breathlessness with an average overnight fall in peak expiratory flow rate of at least 15% during a 2-week run-in period. 2. The lowest peak expiratory flow rate occurred at 02.00-04.00 hours in the group with nocturnal asthma, whose overnight fall in peak expiratory flow rate was 29 +/- 5% in comparison with 5 +/- 1% (means +/- SEM) in the normal subjects. 3. Plasma methylhistamine levels at night (0.200-04.00 hours) were lower than during the day (10.00-20.00 hours) in both asthmatic patients and normal subjects (asthmatic patients: day, median 0.22 ng/ml, 95% confidence intervals 0.18-0.34 ng/ml; night, 0.17 ng/ml, 0.13-0.24 ng/ml; P < 0.01; normal subjects: day, 0.31 ng/ml, 0.24-0.41 ng/ml; night, 0.24 ng/ml, 0.21-0.33 ng/ml; P < 0.01). 4. The serum eosinophil cationic protein level was higher by day (30 ng/ml, 8-47 ng/ml) than by night (21 ng/ml, 5-34 ng/ml; P < 0.04) in the group with nocturnal asthma, but did not change significantly with the time of day in the normal subjects (day: 8 ng/ml, 4-14 ng/ml; night: 8 ng/ml, 5-21 ng/ml).(ABSTRACT TRUNCATED AT 250 WORDS)

Inflammatory mediators and cellular infiltration of the lungs in a guinea pig model of the late asthmatic reaction

Alterations in cell numbers, vascular permeability, and concentrations of various inflammatory mediators in the lung were measured in a guinea pig model of the late asthmatic reaction. Animals sensitized by inhalation of ovalbumin were challenged with an aerosol of ovalbumin or saline, and bronchoalveolar lavage fluid (BALF) and peripheral blood were collected after periods ranging from 5 min to 72 h. Increased vascular leakage within the lungs was indicated by elevated BALF/plasma albumin ratios at all time points, and was maximal 6 h after challenge. There were increased numbers of eosinophils in BALF by 6 h after challenge and they remained elevated at least until 72 h. A corresponding increase in the proportion of blood leukocytes represented by eosinophils was observed at 6 and 17 h, which suggests that these cells may be drawn to the lung following their release into the circulation, but by 72 h the proportion in blood had returned to normal. A transitory neutrophilia was evident in BALF and blood 6 h after allergen exposure, but there were no allergen-induced changes in BALF numbers of macrophages, lymphocytes, epithelial cells, or mast cells (as assessed by concentrations of cell-associated histamine). beta-Glucuronidase activity was significantly increased in BALF of guinea pigs at 2 h and 17 h following challenge. The degree to which eicosanoids can be recovered in BALF was investigated by instilling a range of tritiated compounds into the lungs of normal guinea pigs at the time of lavage. Ratio high-performance liquid chromatography revealed that there had been little metabolism of the eicosanoids recovered in BALF. However, there was evidence for a rapid removal of these mediators from the lung, a process which will militate against their accurate quantitation in BALF. Histamine, prostaglandin D2, and thromboxane B2 were detected in BALF but did not differ between treatment groups, and levels showed no simple relationship with the other inflammatory changes measured.

A young woman with abdominal pain

Patients rarely present with solely a physical problem. While psychological overlay and social factors expand the differential diagnosis and modify management, physical dangers should not be forgotten. Disruption of the family unit isolates individuals and requires extra consideration from the caring practitioner, as in the case of Sarah Leigh.

Fixed cutaneous eruptions to seminal-plasma challenge: a case report

Reactions to human seminal plasma may present as immediate hypersensitivity, cell-mediated hypersensitivity, or fixed eruptions. There are no typical responses to semen. An abnormal skin lesion or systemic response after intercourse may be the only clue to identifying those who are reacting to semen. The use of condoms has proven to be the most consistent preventive modality. However, the use of condoms is unacceptable to some regardless of the relief provided. Although conventional therapy for hypersensitivity reactions to human seminal plasma is suboptimal, one should be aware of MA in the treatment of an atypical cause of human seminal plasma induced reactions.

Chronic atrophic gastritis and risk of N-nitroso compounds carcinogenesis

Chronic atrophic gastritis is considered a precancerous condition for carcinoma of the stomach. To evaluate the correlation between progressive alterations in the mucosa and gastric juice microenvironmental factors, retained involved on N-nitroso compounds carcinogenesis, detailed analyses of biochemical and microbiological parameters such as pH, total viable counts (TVC), nitrate reductase positive bacterial counts (NRPBC), nitrite (NO2-) and thiocyanate (SNC-) levels, were carried out on 56 fasting gastric juices samples obtained at endoscopy from 28 patients with chronic atrophic gastritis (CAG), 14 with gastric cancers (GC), and 14 normal controls (NC). The mean values of pH, nitrite, TVC, and NRPBC were significantly lower in the juices of NC than in those of CAG and GC patients. Furthermore, the mean levels of the same parameters were higher in GC than in CAG juices. No significant difference was found in the three groups for SCN- level which principally resulted influenced by smoke habit. The 28 patients with CAG were subdivided into two groups (Group A = Diffuse chronic atrophic gastritis--DCAG; Group B = Multifocal chronic atrophic gastritis--MCAG) according to the involvement of gastric corpus and fundus besides antrum by a process of mucosal atrophy. The mean levels of pH, nitrite, TVC, and NRPBC were significantly higher in MCAG than in normal controls but statistically lower in reference to DCAG and cancers. In these two groups no difference was found for the same variables. The percentage of contaminated juices was higher for DCAG and cancers in respect to MCAG but no difference was found between DCAG and neoplastic stomachs. The results of this study suggest that the DCAG could be considered as the chronic atrophic gastritis type more exposed to the risk of N-nitroso compounds carcinogenesis.

Ultrasonographic assessment of luteinized unruptured follicle syndrome in unexplained infertility

Ultrasound can be used to monitor the growth and rupture of the dominant follicle. Thirty-three patients with unexplained infertility underwent serial sonography (mean, 3.2 scans/cycle) for luteinized unruptured follicle syndrome (LUFS). The incidence of LUFS was 9% (three patients) in the initial scan cycle. Three patients (9%) demonstrated rupture of a follicle significantly smaller than the mean (22.1 mm) (z less than 0.01) in the initial scan cycle. At standard radiology fees ($7000 +/ diagnosed LUFS) the cost/benefit ratio of this method of diagnosis will be controversial. It is suggested that scanning at reduced fees in the gynecologist's office, particularly in conjunction with postcoital tests, would decrease cost and increase the potential benefit.

Economic comparison of two methods of supplementary feeding in Finnish reindeer management

The most common methods are (1) supplementary feeding with dry hay (maximally 50 kg per head a season) on natural ranges in mid and late winter, and (2) corral feeding, where the reindeer are fed in small yard-corrals with hay, green silage, lichen, molasses and commercial reindeer feeds for 3-5 months a winter.

Suicide and the MMPI: a cross-validation of predictors

Compared a suicide-completion group to a psychiatric control sample on the 13 traditional MMPI scales, three experimental item pools, and eight profile patterns earlier described as indicative of suicidal tendencies (N = 84). Also compared the frequencies with which the groups endorsed each of the 566 MMPI items. The number of resulting significant differences was less than chance. The results argue against the use of the MMPI to predict suicide at this time.

Identification of suicidal episodes with the MMPI

Previous research has not identified MMPI scales, patterns or item sets capable of separating eventual suicide committers from non-committers. Looking for MMPI scales associated with a short-term suicide state, we compared the scores of people who had committed suicide soon after taking the inventory with those of people who killed themselves more than three months later. The Suicide Episode group showed a significantly higher mean score than the Remote Suicide sample on Paranoia, and near-significant differences appeared on six other scales. These results suggest that it may be possible to identify a suicide state with the MMPI, but further research should precede clinical application of these findings.

Collagen crosslinks in human dentin: increasing content of hydroxypyridinium residues with age

The hydroxypyridinium crosslinks of collagen are believed to derive from reducible, divalent crosslinks. To study this concept further, both types of crosslink were quantified as a function of age in dentin, a tissue thought to have minimal collagen turnover. Human (5, 15, 28 and 56 years) and bovine (fetal and adult) root dentin was analyzed by a procedure that measures both hydroxypyridinium and reducible crosslinks on the amino acid analyzer. In human dentin, hydroxypyridinium crosslinks increased with age and became the predominant crosslinks as the two reducible residues, dehydrodihydroxylysinonorleucine and dehydrohydroxylysinonorleucine, diminished. Similarly in adult bovine dentin, hydroxypyridinium residues were sixfold more concentrated than in fetal bovine dentin. Borohydride treatment of tissue did not influence the measured content of hydroxypyridinium residues. The analyses also ruled out natural reduction as a stabilizing reaction for the divalent, reducible crosslinks. Though hydroxypyridinium residues became the major aldehyde-mediated crosslinks of adult dentin collagen, significant levels of reducible crosslinks remain throughout the tooth's adult life.

Intracochlear electrical stimulation of normal and deaf cats investigated using brainstem response audiometry

Brainstem response audiometry for intracochlear electrical stimulation of normal-hearing and deafened cats was investigated. In normal cochleas the brainstem response amplitude grew slowly near threshold as a current-amplitude dependent process, identified as electrophonic in origin. This terminated in a rapidly growing charge-dependent process at approximately 20 dB above threshold, identified as direct electrical stimulation of the auditory nerve. Small levels of white noise (25-35 dB SPL) were sufficient to mask most of the electrophonic response, leaving the direct stimulation process essentially unmodified. In cochleas damaged with d.c. currents and loud sounds, only a rapidly growing charge-dependent process was observed which grew similarly to that in normal-hearing cats but occurred at lower currents. This indicates that possibly the electrical properties of the cochlea were altered in the deafening process, suggesting the inadequacy of normal animals as deaf models for electrical stimulation. Using the technique of derived brainstem responses, it was shown that direct electrical stimulus components were localized to the vicinity of the stimulus electrode with electrophonic components distributed more widely. However, at high currents there was some evidence of the stimulus spreading into the internal auditory meatus.

Haemoglobin H disease in 2 Filipino families

Haemoglobin H disease is described in successive generations of 2 Filipino families. The condition was asymptomatic. The inheritance pattern of haemoglobin H disease in these families appeared to be like that described for Thais.

Epidural hematoma after minor oral trauma

A case report was presented in which a 15-year-old boy was beaten about the head with a baseball bat. Intraoral trauma and facial lacerations were repaired. Since results of the neurological examination were within normal limits, the patient was discharged. The next day, the patient became lethargic; however, the patient's mother did not bring the patient back to the hospital until the routine postoperative visit. At that time, the patient had right hemiparesis, was unable to speak, and was clearly obtunded. A carotid angiogram disclosed a left venous epidural hematoma in the parietal area. A craniotomy was performed with good results. The importance of follow-up neurologic examinations in cases of trauma to the face and head is stressed.