Genotyping of Toxoplasma gondii strains from immunocompromised patients reveals high prevalence of type I strains

Toxoplasma gondii is an important food- and waterborne opportunistic pathogen that causes severe disease in immunocompromised patients. T. gondii has an unusual clonal population structure consisting of three widespread lineages known as I, II, and III. To establish the genotypes of strains of T. gondii associated with human toxoplasmosis, we have developed a set of four highly sensitive and polymorphic nested PCR markers. Multiplex nested PCR analysis was used to genotype parasites in cerebral spinal fluid samples from 8 of 10 human immunodeficiency virus-positive patients. Remarkably, a majority of these patients had infections with type I strains or strains containing type I alleles, despite the fact that this lineage is normally uncommon in humans and animals. Multiplex analysis of these four unlinked makers was able to distinguish all three common genotypes and also detected two strains with mixed genotypes. Further analysis based on sequencing of a polymorphic intron revealed that one of these recombinant strains was an exotic lineage distinct from the archetypal clonal lineages. The multiplex nested PCR analysis described here will be useful for analyzing the contribution of parasite genotype to toxoplasmosis.     

Induction of apoptosis of human primary osteoclasts treated with extracts from the medicinal plant <Emphasis Type="Italic">Emblica officinalis</Emphasis>

Background  

Osteoclasts (OCs) are involved in rheumatoid arthritis and in several pathologies associated with bone loss. Recent results support the concept that some medicinal plants and derived natural products are of great interest for developing therapeutic strategies against bone disorders, including rheumatoid arthritis and osteoporosis. In this study we determined whether extracts of Emblica officinalis fruits display activity of possible interest for the treatment of rheumatoid arthritis and osteoporosis by activating programmed cell death of human primary osteoclasts.     

Pemphigus Vulgaris Autoantibody Response is Linked to HLA-DQB10503 in Pakistani Patients

ABSTRACT: Pemphigus vulgaris (PV) is an autoimmune disease of the skin and mucous membranes characterized by an autoantibody response against an epidermal cadherin. We performed high resolution HLA class II typing in 19 patients with PV from Rawalpindi, Pakistan and 19 non-Jewish European PV patients from Boston by sequence-specific oligonucleotide probe hybridization. The results were compared with two separate ethnically matched control populations. We found that PV patients from Pakistan had significantly increased frequencies of DRB1*1404 ( p = 0.01), DQA1*0101 ( p = 0.02), and DQB1*0503 ( p = 0.01). Among the patients of non-Jewish European ancestry, DRB1*1401 ( p < 10⁻⁶), DQA1*0101 ( p < 10⁻⁵) and DQB1*0503 ( p < 10⁻⁶), were increased in PV patients. Formal linkage analysis between the major histocompatibility complex and the PV antibody was performed in 67 relatives of the 19 Pakistani patients. The results showed strong evidence for linkage of HLA-DRB1*1404, DQA1*0101, DQB1*0503, with the presence of PV antibody in relatives’ families with a significant logarithm of the odds score of 6.06. Based on the three dimensional structure of class II molecules, we propose that HLA-DQA1*0101 and DQB1*0503, encode a negatively charged P9 peptide binding pocket of the DQ molecule and are significantly associated with susceptibility to PV in non-Jewish populations.     

Effect of mebendazole againstEchinococcus granulosus andTaenia hydatigena cysts in naturally infected sheep and relevance to larval tapeworm infections in man

The ability of three treatment schedules of mebendazole to kill well-established hydatid cysts was studied. Pregnant sheep, naturally infected withEchinococcus granulosus and/orTaenia hydatigena, were treated daily with mebendazole at a dose rate of 50 mg/kg body weight for either five days, one month, or three months.At autopsy, seven months after the commencement of treatment, no evidence was found that the 5-day treatment schedule had any damaging effect onE. granulosus cysts. The effects of the one month treatment were equivocal. There was evidence of a damaging effect from the 3-month treatment schedule and protoscoleces were not infective to dogs. NoT. hydatigena cysts survived the 1- and 3-month treatments, but organisms from the 5-day treatment were infective to dogs.These results forE. granulosus in sheep suggest that long-term treatment with mebendazole may be required in hydatid disease in man. The results obtained forT. hydatigena in sheep are discussed in relation to the treatment of cysticercosis fromT. solium in man. Mebendazole showed no untoward effect on the sheep or their lambs.     

Immune dysregulation and autoreactivity correlate with disease severity in SARS-CoV-2-associated multisystem inflammatory syndrome in children

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Laparoscopic salpingotomy for tubal pregnancy: comparison of linear salpingotomy with and without suturing

BACKGROUND: The study was carried out to clarify the incidence of post-operative tubal adhesions, patency rate and pregnancy outcome after laparoscopic salpingotomy with and without suturing for tubal pregnancy. METHODS: From May 1996 to December 2002, a total of 97 cases of tubal pregnancy were treated in our centre by laparoscopic conservative surgery. The successful salpingotomy cases were randomly assigned to undergo salpingotomy without suturing (group I; n = 43) or with suturing (group II; n = 32). We compared these patients and assessed their surgical and pregnancy outcome by second look laparoscopy (SLL) 3 months after the first operation. RESULTS: Seventy-five cases (77%) were treated successfully by salpingotomy at initial laparoscopic surgery, and the remaining 22 cases were unsuccessful because of bleeding or complete tubal damage. Pelvic findings were assessed at SLL in 21 of 43 cases (49%) in group I and 17 of 32 (53%) in group II. There were no significant differences in gestational age, ectopic site, tubal diameter, tubal condition, intraperitoneal haemorrhage and pre-operative HCG levels between the two groups. Only the operation time was longer in group II than in group I (91 +/- 15 versus 69 +/- 15 min, P < 0.05). The tubal patency rate of the treated side was 90% (19/21) in group I and 94% (16/17) in group II. Also the peritubal adhesions were observed in 33% (7/21) in group I and 29% (5/17) in group II, and were mostly comprised of filmy adhesions. A tubal fistula occurred in two cases in each group. Pregnancy rate was 79% (15/19) in group I and 92% (12/13) in group II, and this did not reveal any significant difference of cumulative pregnancy rate between the groups. CONCLUSION: We recommend laparoscopic linear salpingotomy as a useful method in the management of cases with tubal pregnancy who desire future pregnancy. This preliminary study emphasizes that the procedure involving suturing has no additional benefit over the non-suturing technique during salpingotomy.     

Impaired Microvascular Function in Normal Children: Effects of Adiposity and Poor Glucose Handling

Clustering of cardiovascular risk factors is thought to occur early in life. The endothelium is an important regulator of microvascular function. We investigated the relationship between microvascular function and cardiovascular risk factors in 145 normal, healthy children aged 11-14 years. Skin microvascular responses, measured using laser Doppler imaging, to iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP), were negatively correlated with percentage body fat ( r =−0.20, P < 0.05 and r =−0.18, P < 0.05, respectively). Subjects were stratified into quintiles based on 2-h, post-feeding glucose levels. Subjects in the upper glucose quintile (range 7.4-11.4 mmol l⁻¹) showed significantly lower vasodilatation to both ACh (   P < 0.005  ) and SNP (   P < 0.02  ) than those in the lower quintile (range 3.9-4.9 mmol l⁻¹). Waist-to-hip ratio and the fasting insulin resistance index were significantly greater in subjects in the upper quintile than those in the lower quintile ( P < 0.001 and P < 0.05, respectively). Additionally, in subjects in the upper glucose quintile, fasting triglyceride correlated with fasting insulin ( r = 0.59, P < 0.001) and with the fasting insulin resistance index ( r = 0.49, P < 0.009), and plasma levels of cholesterol and 2-h glucose were also correlated ( r = 0.40, P < 0.05). In a cross-section of normal children, microvascular function was negatively associated with adiposity. Additionally, in a subgroup of subjects, there was a clustering of high post-feeding glucose, impaired microvascular function, increased insulin resistance and higher central fat distribution. These findings suggest that risk factors for adult cardiovascular disease begin to cluster in normal children, which might have important consequences for development of atherosclerosis later in life.     

The non-immunosuppressive immunophilin ligand GPI-1046 potently stimulates regenerating axon growth from adult mouse dorsal root ganglia cultured in Matrigel

We used explant cultures of adult mouse dorsal root ganglia with spinal nerve attached growing in Matrigel to assess the effects of the non-immunosuppressive immunophilin ligand GPI-1046 [Snyder et al. (1998) TIPS 19, 21-26] on the growth rate of regenerating sensory axons and found a potent stimulation of axon growth. In these explant cultures, naked, unfasciculated axons emerge from the cut end of the spinal nerve and continue to grow in the Matrigel for up to eight days [Tonge et al. (1996) Neuroscience 73, 541-551]. Some axons are entirely smooth whilst others show prominent varicosities. Some of the former express the phosphorylated neurofilament epitope recognised by monoclonal antibody RT97, a marker for large calibre, myelinated axons, whilst the latter express calcitonin gene-related peptide, predominantly a marker for unmyelinated, and small diameter myelinated sensory axons. Many of the axons in these cultures also express the low-affinity neurotrophin receptor p75. GPI-1046 has been shown to have striking stimulatory effects on embryonic primary sensory axons growing in vitro and it was therefore of interest to see whether it could also enhance regenerating sensory axon growth from the adult ganglia in our cultures. GPI-1046 potently stimulated axon growth in our cultures in a dose-dependent manner. The stimulatory effect was not dependent on the class of sensory axon. These observations show that GPI-1046 is a potent stimulator of regenerating axons from adult, primary sensory neurones. The cellular site of action of GPI-1046 is unknown. To distinguish between a direct effect of the drug on neurones and an indirect effect we compared the effects of GPI-1046 on explant and dissociated cultures. In confirmation of previous results, we found that GPI-1046 potently stimulated axon outgrowth from explants of embryonic chick dorsal root ganglia. However, the drug was without effect on dissociated embryonic dorsal root ganglion neurones, suggesting that non-neuronal cells are important for axon growth stimulation.