Action of permethrin on Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae) semi-engorged females: Morpho-physiological evaluation of salivary glands

Currently the most effective method of tick control is the use of acaricides, among which stands out permethrin (active ingredient of acaricide Advantage^® Max3, Bayer), a neurotoxic pyrethroid. However, assessments of their effects on other tick systems such as glandular are still scarce. Thus, this study provides information, through histochemical techniques, about the toxic effect of this pyrethroid on the morphophysiology of salivary glands of semi-engorged Rhipicephalus sanguineus females exposed to different concentrations of permethrin (206, 1031, and 2062 ppm). The results showed that permethrin caused significant changes in the salivary gland metabolism accelerating the process of glandular degeneration, an event which would occur naturally and with great intensity only in the final engorgement stage. Furthermore, this study pointed out that permethrin reduces the salivary gland secretion ability through a drastic reduction of proteins, lipids, and polysaccharides in acinar cells. These changes impair the females to finalize the feeding process, what indirectly affects the reproductive process.     

Endophthalmitis: a rare but devastating metastatic bacterial complication of hemodialysis catheter-related sepsis

There are many infectious complications related to vascular access in patients undergoing maintenance hemodialysis. We report two cases of endophthalmitis as a metastatic infection associated with a tunneled catheter and a temporary dual lumen catheter. Both patients were diabetic. A 61-year-old female on maintenance hemodialysis by a jugular tunnelized catheter during the past year was receiving parenteral antibiotics for catheter salvage due to fever episodes in the last 3 months. She was admitted to the hospital presenting pain, proptosis, conjunctival hyperemia, corneal infiltrate, and visual acuity of no light perception (NLP). A 51-year-old male recently undergoing hemodialysis by a temporary dual lumen catheter presented fever. His catheter was removed, but he was admitted to the hospital presenting fever, decreased vision, edema, and pain in his left eye. On examination, eyelid edema, conjunctival hyperemia, purulent secretion, hypopyon in the pupils, and visual acuity of NLP were verified. A diagnosis of endogenous endophthalmitis was made in both patients on clinical grounds and computed tomography. Evisceration of the left eye was the first option of treatment for both patients due to poor vision. Cultures of the eviscerated ocular globes showed Staphylococcus hemolyticus and Staphylococcus aureus, respectively. After evisceration, both patients received treatment, had a good outcome, and were discharged to continue their hemodialysis program. Metastatic bacterial endophthalmitis is a rare complication of dialysis catheter-related bacteremia. When suspected, urgent ophthalmologic evaluation and treatment are needed to reduce the risk of losing vision in the affected eye.     

La vérité dans le contexte de la garde à vue

Today, the gendarmerie in France is equipped with a specialist service to help with inquiries, the Department of Behavioural Science. This department assists with inquiries involving homicide and serial rape by looking purely at the psychological, and focusing in particular upon a suspect's behaviour during police interviews. It is in this constrained environment where a suspect is most likely to lie or clam up that the interviewer must obtain the truth from a suspect, a truth which can only be subjective. In preparation for a hearing, a criminological evaluation of the facts and a study of the personality of the suspect are conducted. The frequent absence of an element of proof in the case handled means that adopting a more rigorous approach including the psychological profile of the suspect is necessary. It is therefore crucial that between the interviewer and the suspect a relationship in which confidences are exchanged is cultivated. In this context, the search for the truth depends upon the detection of a lie. But lies can only be detected by those who help an inquiry. Currently, the search for the truth is still very often in convincing a suspect to confess, the aim being for the interviewer to ‘make the suspect talk’. Although the truth, it can be argued, is independent of a confession. In fact, to base evidence upon the lies, contradictions and inconsistencies in a case can sometimes provide more proof than the confession itself. To receive a truthful interview and confession from a suspect in a limited amount of time to provide evidence for a case is a difficult exercise. Knowing the dynamic of a case, it seems illusory to look for an absolute truth, especially during an interview with a suspect. It would be better to open up the possibilities without making errors and so that the truth may be eventually found.     

Leishmania tropica in Egypt: an undesirable import

Cutaneous as well as visceral leishmaniasis has been previously reported in Egypt. The former clinical manifestation is attributed to Leishmania major, the latter to L. infantum. In this study, L. tropica was isolated from an Egyptian labourer returning from Saudi Arabia. Amastigotes were detected by both Giemsa staining and indirect immunofluorescence using rabbit anti-gp63. Promastigotes from Schneider's medium were typed isoenzymatically as L. tropica. In view of the emerging threat of visceralization of L. tropica, the potential risk for its transmission in Egypt is discussed.     

Morphology and bacterial colonisation of tooth/ceramic restoration interface after different cement excess removal techniques

Objectives

To evaluate the influence of different protocols for resin cement removal during cementation on biofilm formation.

Methods

Twenty-eight ceramic blocks, which were injected under pressure, were placed over enamel blocks obtained from freshly extracted bovine incisors. The ceramic blocks were cemented to the enamel blocks using a dual-cured resin cement and the excess resin was removed according to the experimental group: TS: Teflon spatula; BR: brush; BR+: brush and polishing; SB+: scalpel blade and polishing. After autoclaving, the samples were colonised by incubation in a sucrose broth suspension standardised with Streptococcus mutans in microaerophilic stove. Specimens were quantitatively analysed for bacterial adherence at the adhesive interface using confocal laser scanning microscopy and counting the colony forming units, and qualitatively analysed using SEM. The roughness (Ra/Rz/RSm) was also analysed. Data were analysed by 1-way ANOVA and Tukey's test (5%).

Results

The roughness values ranged from 0.96 to 1.69 μm for Ra (p > 0.05), from 11.59 to 22.80 μm for Rz (p = 0.02 < 0.05) and from 293.2 to 534.3 μm for RSm (p = 0.00). Bacterial adhesion varied between 1,974,000 and 2,814,000 CFU/ml (p = 0.00). Biofilm mean thickness ranged from 0.477 and 0.556 μm (p > 0.05), whilst the biovolume values were between 0.388 and 0.547 μm³/μm² (p = 0.04). Lower values for roughness, bacterial adhesion, biofilm thickness and biovolume were found with BR, whilst TS presented the highest values for most of the parameters. SEM images confirmed the quantitative values.

Conclusions

The restoration margin morphology and interface roughness affects bacterial accumulation. The brush technique promoted less bacterial colonisation at the adhesive interface than did the other removal methods.

Clinical significance

The brush technique seems to be a good option for removing the excess resin cement after adhesive cementation in clinical practice, as indicated by its better results with lower bacterial colonisation.     

Vascular morphometry and micrometry of the orbital region of the human optic nerve

The study aims at providing data on the vascular morphometry and micrometry of the orbital region of the human optic nerve. The disposition of the microcirculatory trunk in the orbital region has been studied on 40 samples taken post-mortem, as well as on 10 pieces from subjects having undergone enucleation. Histological specimens were prepared from the optic nerves using eosinhematoxylin dye-staining, the Romhany-Barzu staining and the Gomory trichromic staining. Functionally active capillaries make up 19.380 per cent (7-14 micro group), respectively 21.318 per cent (15-20 micro group) of the total vessels in the area, having an average diameter of 10.01 +/- 0.0826085 p, respectively 17.9272 +/- 0.0651995 micro, for P = 0.05. There are 169 reserve capillaries (with a diameter between 2-6 micron), representing 32.752 of the total of vessels counted. The existence of reserve capillaries allows, at a certain point, for the supplying of the obstruction or of the vasospasm on the territory of the functionally active capillary     

Mesenchymal stem cells cooperate with bone marrow cells in therapy of diabetes

Several recent studies have suggested that the adult bone marrow harbors cells that can influence beta-cell regeneration in diabetic animals. Other reports, however, have contradicted these findings. To address this issue, we used an animal model of type 1 diabetes in which the disease was induced with streptozotocin in mice. Freshly prepared sex-mismatched bone marrow cells (BMCs) and syngeneic or allogeneic mesenchymal stem cells (MSCs) were concomitantly administrated into sublethally irradiated diabetic mice. Blood glucose and serum insulin concentrations rapidly returned to normal levels, accompanied by efficient tissue regeneration after a single injection of a mixture of 10(6) BMCs per 10(5) MSCs. Neither BMC nor MSC transplantation was effective alone. Successful treatment of diabetic animals was not due to the reconstitution of the damaged islet cells from the transplant, since no donor-derived beta-cells were found in the recovered animals, indicating a graft-initiated endogenous repair process. Moreover, MSC injection caused the disappearance of beta-cell-specific T lymphocytes from diabetic pancreas. Therefore, we suggest that two aspects of this successful treatment regimen operate in parallel and synergistically in our model. First, BMCs and MSCs induce the regeneration of recipient-derived pancreatic insulin-secreting cells. Second, MSCs inhibit T-cell-mediated immune responses against newly formed beta-cells, which, in turn, are able to survive in this altered immunological milieu. Thus, the application of this therapy in human patients suffering from diabetes and/or other tissue destructive autoimmune diseases may be feasible.