Nested primers improve sensitivity in the detection of Helicobacter pylori by the polymerase chain reaction

To investigate potential routes of spread of infection by the polymerase chain reaction (PCR) it is important that the technique is effective in the types of specimen to be investigated. To establish the limits of detection of Helicobacter pylori by PCR in clinical material from the gastric mucosa, faeces, dental plaque and oral rinses, samples were seeded with known numbers of bacteria. DNA extraction was followed by amplification with primers from the urease C gene. Nested primers were used to amplify the PCR product which was detected using a digoxigenin-labelled probe. Faeces or plaque inhibited the single reaction 10(2)-10(6) fold. A second amplification using nested primers and probing increased the sensitivity to a level similar to that obtained with pure culture. This method is potentially useful with less likelihood of false negative results when trying to detect H. pylori by PCR in highly contaminated, clinical material.

Intravascular fasciitis: a case report and review of the literature

A 49 year old man presented with a mass in the inguinal region that for 3 mths had been associated with slight discomfort. Clinically the mass was thought to be an enlarged lymph node. Histology however showed nodular fasciitis. There was also an associated smaller lesion that was histologically identical and which involved the wall of a medium sized vein with protrusion into its lumen. These appearances were typical of intravascular fasciitis. Review of the Royal Brisbane Hospital Pathology files for 12 yrs from 1982, revealed no other such cases. We describe here the clinical and pathological features of this case and review the literature on this rare condition.

Nodular fasciitis and related pseudosarcomatous lesions of soft tissues

BACKGROUND

Nodular fasciitis is characterized by a proliferation of spindle cells which may be misdiagnosed as sarcomas due to the rich cellularity, mitotic activity and variant morphologic patterns.

METHODS

This report includes 42 cases of nodular fasciitis and related conditions of skin and soft tissue from the pathology files of the Royal Brisbane Hospital, Queensland, Australia. There were 33 cases of nodular fasciitis, three cases of ossifying fasciitis, three cases of proliferative fasciitis, two cases of proliferative myositis and one case of intravascular fasciitis. Two-thirds of cases were referred from outside Royal Brisbane Hospital.

RESULTS

Nodular fasciitis and ossifying occurred most commonly in young adults with 16 patients (44%) between the ages of 20 and 29. However, the other variants of nodular fasciitis including proliferative myositis and intravascular fasciitis occurred in older people (six patients being older than 49 years) and more commonly occurring in men (n=5). A painless rapidly growing mass was most common. The lesions of nodular fasciitis were most often located in the upper extremity with the forearm most commonly affected.

CONCLUSIONS

Nodular fasciitis and related conditions are benign. All patients are alive and well 3 months to 13 years (mean 7.2 years) after simple local resection.

A comparison of the psychosocial aspects of AIDS and cancer-related bereavement

OBJECTIVE

This study compares the psychological symptoms and bereavement distress of individuals bereaved by AIDS with a group bereaved by a cancer death, and addresses the question of whether an AIDS death is associated with a higher rate of adverse psychosocial factors that may increase risk of psychological morbidity in the bereaved individuals.

METHOD

AIDS (n = 28) and cancer (n = 30) bereaved individuals (all within 3 months of the bereavement) completed measures of psychological morbidity and measures addressing a range of other adverse factors, e.g., number of losses, levels of social support and stigma.

RESULTS

The cancer and AIDS bereaved were essentially similar on all psychological symptom measures. The AIDS group reported lower levels of social support in response to the bereavement than cancer bereaved individuals; a greater number of bereavements, were more likely to conceal the cause of death from significant others including their own family and perceived, in some instances, a greater level of rejection from others. The AIDS group reported higher levels of social support from friends than from family.

CONCLUSIONS

At three months following bereavement, AIDS and cancer bereaved were similar in levels of distress. While this may change with the progress of grief over time, it suggests essentially similar early bereavement responses. Those bereaved by AIDS reported a range of other adverse factors such as a greater number of losses, lower social support, stigma, and less open disclosure of the cause of death.

Modulatory action of Helicobacter pylori on histamine release from mast cells and basophils in vitro

Helicobacter pylori is important in the aetiology of peptic ulceration. Despite inducing an inflammatory response in the mucosa, the organism persists, suggesting that it has efficient protective mechanisms. Some bacterial and viral products modulate histamine secretion from inflammatory cells. Therefore, this study examined the modulatory effects of H. pylori preparations on histamine release from rat peritoneal mast cells and human basophils. Eleven clinical isolates of H. pylori were prepared in different ways: as whole washed bacteria, washed sonicated bacteria, and formalin-killed bacteria, and as outermembrane and lipopolysaccharide (LPS) extracts. Histamine release from mast cells or basophils was not elicited by any of these bacterial preparations alone. However, when mixed with various secretory stimulants, the bacterial preparations caused inhibition of histamine release from rat mast cells (calcium ionophore A23187, compound 48/80, concanavalin A, anti-rat IgE) and human basophils (A23187, N-formyl Met-Leu-Phe). The degree of inhibition ranged from 48% to 97%. These results indicate that H. pylori exerts an inhibitory effect on cells of the immune system that contributes to its persistence within the gastric mucosa.

The life span of new neurons in a song control nucleus of the adult canary brain depends on time of year when these cells are born

The number of high vocal center (HVC) neurons labeled in adult male canaries by systemic injections of [3H]thymidine depended on season and survival time. This was true for HVC neurons projecting to the robust nucleus of the archistriatum and for other HVC neurons that could not be retrogradely filled from the robust nucleus of the archistriatum. Birds injected in October and killed 40 days later had twice as many labeled HVC neurons as birds injected in May and killed 40 days later. However, this difference became much larger (5 times) when the birds were allowed to survive for 4 months. Whereas more than half of the spring-born neurons disappeared between 40 days and 4 months, there was no reduction in the number of fall-born neurons present at the 4-month survival point. We infer that seasonal variables affect the life span of HVC neurons born in adulthood.

Cell death and neuronal recruitment in the high vocal center of adult male canaries are temporally related to changes in song

Adult male canaries modify their song every year. Most of these changes occur during late summer and early fall, after the end of the breeding season, and in late winter, immediately before the onset of the next breeding season. The high vocal center (HVC) is an important nucleus in the brain pathway that controls this learned behavior. New neurons continue to be added to the HVC of adult male canaries, where they replace older neurons that have died. The present report describes the monthly incidence of cell death and neuronal addition in the HVC of such birds. Different groups of 1- to 2-year-old male canaries were treated with [3H]thymidine, a marker of cell birth, during each month of the year and killed 27 days later. The ratio of 3H-labeled neurons to all neurons in the HVC showed seasonal peaks and troughs. This ratio was highest in October and March. Peaks in the ratio of pycnotic (dying) HVC cells to all neurons in HVC preceded the peaks in the ratio of 3H-labeled neurons. We suggest that seasonal peaks in cell loss and neuronal recruitment in HVC are related to endocrine changes and that all three play a role in the seasonality of song modification.

Diagnosis of ruptured diaphragm following blunt trauma: results from 85 cases

Between 1975 and 1990, 85 patients with diaphragmatic rupture following blunt trauma were treated at the Royal Brisbane and Princess Alexandra Hospitals, Brisbane. There were 65 on the left, 17 on the right and three were bilateral. Road trauma was the cause in 88% of cases. In the first 48 h the diagnosis was made by chest X-ray in 51 patients, laparotomy in 22, autopsy in two, emergency room thoracotomy, ultrasound and pneumoperitoneum each in a single patient. Seven patients (8%) had delay in diagnosis greater than 48 h ranging from 6 days to 6 months. Diagnosis was subsequently made by pneumoperitoneum (3), chest X-ray (1) and exploratory thoracotomy (1). Two patients presented with a strangulated diaphragmatic hernia 3 and 6 months following an acute admission with blunt chest trauma and urological trauma respectively. During the study period a further five patients presented with an obstructing diaphragmatic hernia. Sixteen patients died (19%), fifteen from associated injuries and one related to the diaphragmatic repair. Ruptured diaphragm should be suspected in patients with severe chest trauma, particularly those requiring positive pressure ventilation, patients with intra-abdominal injuries and those with pelvic fractures. Early recognition and repair results in low morbidity and mortality. Measures that confirmed the diagnosis in patients with delay included repeated chest X-rays and pneumoperitoneum.

On variables that affect estimates of the true sizes and densities of radioactively labeled cell nuclei

Tritiated thymidine has been widely used as a nuclear marker of cell birth. The true diameters and packing densities (nuclei/microns 3) of such radioactively labeled nuclei cannot be measured directly from tissue sections. Here we show that existing stereological corrections cannot be applied to data from radioactively labeled nuclei. We empirically measured the number of silver grains exposed by nuclei containing tritiated thymidine. The nuclei were separated from the photographic emulsion by known thicknesses of fixed, embedded avian telencephalon. The results of this experiment were used to develop an equation that estimates the number of silver grains exposed by a cell nucleus of any given diameter, containing a given amount of radioactive label, and located at any given distance from the photographic emulsion. The equation also allows one to calculate the probability that a label-containing nucleus will be correctly classified as labeled. Simulations of the equation revealed that not all label-containing nuclei are correctly classified by using commonly employed identification procedures and that larger nuclei are less likely to be correctly classified than smaller nuclei, given the same amount of label. The equation can be used to modify one class of existing stereological equations so as to be applicable to measurements of radioactively labeled nuclei. Finally, we discuss the assumptions and limitations of this modification.