AIDS retrovirus antibodies in hemophiliacs treated with factor VIII or factor IX concentrates, cryoprecipitate, or fresh frozen plasma: prevalence, seroconversion rate, and clinical correlations

Antibodies to the AIDS retrovirus, specifically to human T cell lymphotropic virus, type III, and AIDS-associated retrovirus, were detected with increasing prevalence in a population of 190 hemophiliacs from western Pennsylvania between 1981 and 1984: 7.7% in 1981, 20.0% in 1982, 45.5% in 1983, and 62.5% in 1984. The seropositive included approximately three fourths of those receiving factor VIII concentrate, nearly one third of those receiving factor IX concentrate, nearly one fifth of those receiving cryoprecipitate, and none of those receiving fresh frozen plasma. The seroconversion rate, determined on 43 seropositive hemophiliacs from this group who were serially sampled, was 0% in 1977, 4.7% in 1978, 4.9% in 1979, 2.6% in 1980, 10.5% in 1981, 52.9% in 1982, 87.5% in 1983, and 100% in 1984. Of 27 seropositive for three or more years (since 1982 or before), four (15%) have developed AIDS and seven (26%), diffuse lymphadenopathy (ARC); of 16 seropositive for less than three years, none has developed AIDS and three (19%) have developed ARC. The mean time from seroconversion to onset of ARC, 0.8 +/- 0.2 years (SEM), was shorter (P less than .001) than the time to onset of AIDS, 4.1 +/- 0.6 years. These findings confirm the widespread presence of AIDS retrovirus and support the association of these retroviruses with the acquired immunodeficiency syndrome and related conditions.     

On duodenal stump leakage caused by adult human Taenia

To the editor： Shao Xinxin and colleagues recently described a case of duodenal stump leakage caused by Taenia saginata （T.saginata）. Apparently, they did not identify the discharged adult tapeworm recovered after the treatment neither morphologically nor molecularly. The authors concluded that the species responsible for the symptoms was T. saginata based on the fact that the patient mentioned that he had been infected by T. saginata two years ago.     

Effects of recombinant human erythropoietin on megakaryocytes and on platelet production in the rat

The contention that erythropoietin (Epo) affects platelet production was investigated in the rat with recombinant human Epo (rHuEpo). In normal rats, Epo caused a dose-dependent increase in both reticulocyte and platelet numbers, the reticulocyte response preceding that of platelets. Withdrawal of Epo resulted in reticulocytes and platelets returning to control levels. [75Se]-selenomethionine incorporation into platelets was also enhanced in response to Epo. Chronic daily administration of rHuEpo resulted in steady state erythrocyte levels after 12 to 14 days, which were elevated 20% above controls. Attainment of this steady state was associated with both reticulocytes and platelets returning to control levels despite continued administration of Epo, an effect not associated with a change in the half-life of circulating Epo. In polycythemic rats a platelet response was observed before an effect on reticulocytes. Erythropoietin caused a 2.4-fold increase in the frequency of small acetylcholinesterase-positive cells within 24 hours, and increased the mean megakaryocyte diameter within 48 hours. Furthermore, the [3H]-thymidine labeling index of megakaryocytes from rats treated for 24 hours with rHuEpo was increased for all stages of megakaryocyte maturation. These results support the proposal of an effect of Epo on rat megakaryocytes causing increased platelet production.     

A clinical trial of MK-507, Trusopt, for raised intraocular pressure - The Australian Experience

Background: Since the introduction of carbonic anhydrase inhibitors, a topical preparation has been sought to avoid the complications of systemic medication while retaining the effect of lowering intraocular pressure. Recently, a topical carbonic anhydrase inhibitor, MK-507, has been found superior to others and introduced for multicentre clinical trial.
Patients and methods: As part of an international rnulticentre trial, we compared MK-507 with beta blockers for one year in 20 patients with raised intraocular pressure, both as monotherapy and in combination.
Results: Twelve patients with a mean peak pressure of 31.9 ± 6.8 mmHg (range, 22 to 49 mmHg) off all medication received MK-507. After two weeks, mean peak pressure was 24.7 ± 6.1 mmHg (range, 14 to 41 mmHg) — a 22.6% fall in pressure. Six of these patients had a mean peak pressure of 27.8 ± 6.4 mmHg (range, 21 to 41 mmHg), a fall of 19.2% from day one and were given timolol as add-on therapy. This resulted in a fall to 19.1 ± 2.8 (range, 15 to 24 mmHg) at year one, a fall of 31.3% after add-on. Four patients on timolol and four on betaxolol gave similar falls in pressure with an additional fall when MK-507 was used as add-on therapy.
Conclusions: MK-507 demonstrated its effectiveness as an ocular hypotensive agent in this trial of patients with an unusually high rise in pressure. It showed a hypotensive effect roughly equivalent to beta blockers. It is likely that either a topical carbonic anhydrase inhibitor or a cardioselective beta blocker will be the medication of first choice in newly diagnosed glaucoma.     

Partial protein S gene deletion in a family with hereditary thrombophilia

Familial thrombophilia, the hereditary predisposition to venous thromboembolic disease, is associated with a protein S deficiency in approximately 8% of the cases. Laboratory measurements of total protein S antigen in affected families have indicated that heterozygotes, ie, individuals carrying both a normal and a defective protein S gene, are severely at risk of developing venous thrombosis at a young age. The recent isolation of protein S cDNA has enabled us to start a search for genetic defects in the protein S gene of heterozygotes. Using Southern blotting on probands of six unrelated families with hereditary protein S deficiency, one proband was found to have a grossly abnormal gene pattern. The abnormality appears to involve at least the deletion of the middle portion of the protein S coding sequence. Family analysis showed that the defect cosegregates with the protein S deficiency. These data agree with the notion that hereditary thrombophilia associated with protein S deficiency is indeed directly the result of a defect in the protein S gene.     

Influence of low and high frequency inputs on spike timing in visual cortical neurons

Cortical neurons in vivo respond to sensory stimuli with the generation of action potentials that can show a high degree of variability in both their number and timing with repeated presentations as wells as, on occasion, a high degree of synchronization with other cortical neurons, including in the gamma frequency range of 30-70 Hz. Here we examined whether or not this variability may arise from the intrinsic mechanisms of action potential generation in cortical regular spiking, fast spiking and intrinsic burst-generating neurons maintained in vitro. For this purpose, we performed intracellular recordings in slices of ferret visual cortex and activated these cells with the intracellular injection of various current waveforms. Some of these waveforms were derived from barrages of postsynaptic potentials evoked by visual stimulation recorded in vivo; others were artificially created and contained various amounts of gamma range fluctuations; finally, others consisted of swept-sinewave current (ZAP current) functions. Using such stimuli, we found that, as expected given the resistive and capacitive properties of cortical neurons, low frequencies have a larger effect on the membrane potential of cortical neurons than do higher frequencies. However, increasing the amount of gamma range fluctuations in a stimulus leads to more precise timing of action potentials. This suggests that different frequencies play different roles, low frequencies being efficient for depolarizing cells with high frequencies increasing the precision of action potential timing. In parallel to increases in temporal precision, the addition of higher frequency components increases the range of interspike intervals present in the action potential discharge. These results suggest that higher frequency components such as gamma range fluctuations may facilitate the generation of action potentials with a high temporal precision while at the same time exhibiting a high degree of variability in interspike intervals on single trials. This temporal precision may facilitate the use of temporal codes or the generation of precise synchronization for the transmission and analysis of information within cortical networks.      

Prevalence of Candida co-infection in patients with pulmonary tuberculosis

Background

Candida species are emerging as a potentially pathogenic fungus in patients with broncho-pulmonary diseases. The synergistic growth promoting association of Candida and Mycobacterium tuberculosis has raised increased concern for studying the various Candida spp . and its significance in pulmonary tuberculosis patients during current years.

Aims

This study was undertaken with the objective of discovering the prevalence of co-infection caused by different Candida species in patients with pulmonary tuberculosis.

Method

A total of 75 patients with pulmonary tuberculosis diagnosed by sputum Ziehl-Neelsen staining were included in the study. Candida co-infection was confirmed using the Kahanpaa et al. criteria. Candida species were identified using gram stain morphology, germ tube formation, morphology on cornmeal agar with Tween-80, sugar fermentation tests and HiCrome Candida Agar.

Results

Candida co-infection was observed in 30 (40%) of patients with pulmonary tuberculosis. Candida albicans was the most common isolate observed in 50% of the patients with co-infection, followed by C. tropicalis (20%) and C. glabrata (20%). Candida co-infection was found in 62.5% of female patients, while it was observed in only 29.4% of the male patients (P value 0.0133). Mean ± SD age of the patients with C. glabrata infection was 65.83 ± 3.19, while the mean ± SD age of the patients with other Candida infections was 43.25 ± 20.44 (P value 0.0138).

Conclusion

Many patients with pulmonary tuberculosis have co-infection with Candida spp. The prevalence of non-albicans Candida species is increasing and may be associated with inadequate response to anti-tubercular drugs. C. glabrata infection has a strong association with old age.     

Ultrasonographic evidence of Gatekeeper™ prosthesis migration in patients treated for faecal incontinence: a case series

Background

Faecal incontinence (FI) is both a medical and social problem, with an underestimated incidence. For patients with internal anal sphincter damage, implantation of biomaterial in the anal canal is a recognised treatment option. One such material, Gatekeeper?, has previously shown promising short- and medium-term results without any major complications, including displacement. The main aim of the present study is to assess the degree to which displacement of Gatekeeper prostheses may occur and to determine whether this is associated with patient outcomes.

Methods

Seven patients (six females) with a mean age of 55.6 years [50.5–57.2] and a mean FI duration of 6 ± 2 years were prospectively enrolled in the study. Each subject was anaesthetised and underwent implantation of six prostheses in the intersphincteric region, guided by endoanal 3D ultrasound (3D-EAU). Follow-up was performed at post-interventional months 1, 3, and 12 (median 12 ± 4 months), during which data were obtained from a defaecation diary, Wexner scale assessment, anorectal manometry (ARM), 3D-EAU, and a health status and quality of life questionnaire (FIQL).

Results

At 3-month follow-up, 3D-EAU revealed displacement of 24/42 prostheses in 5/7 patients. Of these, 15 had migrated to the lower portion and 9 to the upper portion of the anal canal and rectum. Despite this migration, treatment was considered successful in 3/7 patients. In one patient, it was necessary to remove a prosthesis due to spontaneous extrusion.

Conclusions

We have shown that displacement of the Gatekeeper? prosthesis occurs, but is not associated with poorer clinical outcomes.