Infectious diseases in paediatric pathology: experience from a developing country

Infectious and parasitic diseases have always challenged man. Although many of them are typically seen in some areas of the world and can be adequately managed by just improving socioeconomic status and sanitary conditions, they are still quite prevalent and may sometimes be seen outside their original geographical areas. Human migration due to different reasons, tourism, blood transfusion and solid organ transplantation has created new concerns for health professionals all over the world. If not for diagnostic purposes, at least these tropical and infectious diseases should be largely known because their epidemiology, pathogenesis, host/parasite interaction, inflammatory and reparative responses are quite interesting and teach us about human biology. Curiosity is inherent to pathology practice and so we are compelled to look for things other than tumours or degenerative diseases. This review focuses on infectious and parasitic diseases found in a developing country and brings up-to-date information on diseases caused by viruses (dengue, yellow fever), bacteria (typhoid fever, leprosy), parasites (Chagas' disease, cutaneous and visceral leishmaniasis, amoebiasis, Capillaria hepatica, schistosomiasis, cysticercosis) and caused by fungi (paracoccidioidomycosis, cryptococcosis, histoplasmosis) that may be useful for pathologists when facing somewhat strange cases from developing countries.     

CD4(+) T cells defined by their Vβ T cell receptor expression are associated with immunoregulatory profiles and lesion size in human leishmaniasis

Leishmaniasis is caused by infection with the protozoan parasite, Leishmania, that parasitizes human cells, and the cellular immune response is essential for controlling infection. In order to measure the host T cell response to Leishmania infection, we have measured the expansion, activation state and functional potential of specific T cells as identified by their T cell receptor Vβ region expression. In a group of cutaneous leishmaniasis (CL) patients, we evaluated these characteristics in nine different T cell subpopulations as identified by their Vβ region expression, before and after specific Leishmania antigen stimulation. Our results show: (1) an increase in CD4(+) T cells expressing Vβ 5·2 and Vβ 24 in CL compared to controls; (2) a Leishmania antigen-induced increase in CD4(+) T cells expressing Vβ 5·2, 11, 12 and 17; (3) a profile of previous activation of CD4(+) Vβ 5·2-, 11- and 24-positive T cells, with higher expression of CD45RO, HLA-DR, interferon-γ, tumour necrosis factor-α and interleukin-10 compared to other Vβ-expressing subpopulations; (4) a positive correlation between higher frequencies of CD4(+) Vβ5·2(+) T cells and larger lesions; and (5) biased homing of CD4(+) T cells expressing Vβ 5·2 to the lesion site. Given that CL disease involves a level of pathology (ulcerated lesions) and is often followed by long-lived protection and cure, the identification of specific subpopulations active in this form of disease could allow for the discovery of immunodominant Leishmania antigens important for triggering efficient host responses against the parasite, or identify cell populations most involved in pathology.     

Implants,Mechanical Devices,and Vascular Surgery for Erectile Dysfunction

IntroductionThe field of erectile dysfunction (ED) is evolving and there is a need for state-of-the-art information in the area of treatment.AimTo develop an evidence-based, state-of-the-art consensus report on the treatment of erectile dysfunction by implants, mechanical devices, and vascular surgery.MethodsTo provide state-of-the-art knowledge concerning treatment of erectile dysfunction by implant, mechanical device, and vascular surgery, representing the opinions of 7 experts from 5 countries developed in a consensus process over a 2-year period.Main Outcome MeasureExpert opinion was based on the grading of evidence-based medical literature, widespread internal committee discussion, public presentation, and debate.ResultsThe inflatable penile prosthesis (IPP) is indicated for the treatment of organic erectile dysfunction after failure or rejection of other treatment options. Comparisons between the IPP and other forms of ED therapy generally reveal a higher satisfaction rate in men with ED who chose the prosthesis. Organic ED responds well to vacuum erection device (VED) therapy, especially among men with a suboptimal response to intracavernosal pharmacotherapy. After radical prostatectomy, VED therapy combined with phosphodiesterase type 5 therapy improved sexual satisfaction in patients dissatisfied with VED alone. Penile revascularization surgery seems most successful in young men with absence of venous leakage and isolated stenosis of the internal pudendal artery following perineal or pelvic trauma. Currently, surgery to limit venous leakage is not recommended.ConclusionsIt is important for the future of the field that patients be made aware of all treatment options for erectile dysfunction in order to make an informed decision. The treating physician should be aware of the patient's medical and sexual history in helping to guide the decision. More research is needed in the area of revascularization surgery, in particular, venous outflow surgery. Hellstrom WJG, Montague DK, Moncada I, Carson C, Minhas S, Faria G, and Krishnamurti S. Implants, mechanical devices, and vascular surgery for erectile dysfunction.     

Ability of laser fluorescence device associated with fluorescent dyes in detecting and quantifying early smooth surface caries lesions

A laser fluorescence (LF) device is a portable tool, but it does not measure minor mineral changes. Our in vitro study aim is to propose the association of an LF with two fluorescent dyes and to evaluate the performance in detecting and quantifying early demineralization. Artificial caries lesions are created in 40 primary canine teeth using a demineralizing solution (pH=4.8) for 12, 24, 48, and 96 h. LF measurements are performed with DIAGNOdent after demineralization in these samples and in 20 sound primary teeth. Measurements with LF with 0.2-mM tetrakis(N-methylpyridyl)porphyrin (LF TMPyP) and with 4-mM protoporphyrin IX (LF PPIX) are made. The amount of calcium loss is determined by atomic emission spectrometry. A correlation between LF and LF with dyes and mineral loss and receiver operating characteristics analysis are performed, as well as comparisons of sensitivity, specificity, and accuracy values. Significant correlation is obtained with LF TMPyP and mineral loss of lesions demineralized for 24, 48, and 96 h. Better performance is achieved with LF TMPyP for all parameters than with LF alone. LF PPIX does not present good results. In conclusion, LF TMPyP provides good performance in detecting and quantifying very early enamel caries lesions.     

Functional changes are associated with tracheal structural abnormalities in patients with acromegaly

Introduction

Although impaired pulmonary function and respiratory sleep disorders are described as responsible for increased mortality in acromegalic patients, little is known about the tracheal abnormalities in this group of patients. Thus, the objectives of this study were to describe the tracheal structural abnormalities and correlate these changes with the respiratory function and clinical data of acromegalic patients.

Material and methods

This is a cross-sectional study that was carried out at two university hospitals. Twenty acromegalic patients underwent spirometry, forced oscillation technique, and computed tomography (CT) assessments. Dyspnea and daytime sleepiness were assessed using the Modified Medical Research Council (MMRC) scale and the Epworth Sleepiness Scale (ESS), respectively. Forty matched subjects served as controls.

Results

The acromegalic patients exhibited larger median ratios between forced expiratory flow and forced inspiratory flow at 50% of the forced vital capacity (FEF_50%/FIF_50%) (2.05 vs. 1.06, p = 0.0001) compared with healthy volunteers. In the CT analysis, acromegalic patients exhibited larger median differences between their cervical and thoracic tracheal diameters (Δ tracheal diameters) (3 vs. 1 mm; p = 0.003). An association was found between FEF_50%/FIF_50% and the following variables: mean resistance (Rm), cervical tracheal diameter, and Δ tracheal diameters. Rm also exhibited a negative correlation with cervical tracheal diameter. Neither the MMRC scale nor the ESS exhibited any significant correlation with large airway obstruction (LAO) indices or with the measured tracheal diameters.

Conclusions

Acromegalic patients have tracheal structural abnormalities which are associated with functional indicators of LAO but not with clinical data.     

Occult hepatitis B virus infection in liver transplant patients in a Brazilian referral center

Estimates of occult hepatitis B virus (HBV) infection prevalence varies amongdifferent studies depending on the prevalence of HBV infection in the studypopulation and on the sensitivity of the assay used to detect HBV DNA. Weinvestigated the prevalence of occult HBV infection in cirrhotic patients undergoingliver transplantation in a Brazilian referral center. Frozen liver samples from 68adults were analyzed using a nested polymerase chain reaction assay for HBV DNA. Thespecificity of the amplified HBV sequences was confirmed by direct sequencing of theamplicons. The patient population comprised 49 (72.1%) males and 19 (27.9%) femaleswith a median age of 53 years (range=18-67 years). Occult HBV infection was diagnosedin three (4.4%) patients. The etiologies of the underlying chronic liver disease inthese cases were alcohol abuse, HBV infection, and cryptogenic cirrhosis. Two of thepatients with cryptic HBV infection also presented hepatocellular carcinoma. Markersof previous HBV infection were available in two patients with occult HBV infectionand were negative in both. In conclusion, using a sensitive nested polymerase chainreaction assay to detect HBV DNA in frozen liver tissue, we found a low prevalence ofoccult HBV infection in cirrhotic patients undergoing liver transplant, probably dueto the low prevalence of HBV infection in our population.     

An innovative quaternary ammonium methacrylate polymer can provide improved antimicrobial properties for a dental adhesive system

A quaternary ammonium methacrylate polymer (QAMP) with antimicrobial potential was synthesized. The resulting product (QAMP) was characterized by FTIR spectroscopy, NMR spectroscopy, visible spectrophotometry, XRPD and TGA. The in vitro susceptibility tests against Streptococcus mutans of QAMP were investigated prior and after incorporation into a commercial adhesive system (Clearfil? SE Bond). The release of quaternary ammonium compounds from the experimental adhesive system (Clearfil? SE Bond?+?5% QAMP) was performed during 1, 7, 14, 21 and 30 days. Spectroscopic data confirmed that QAMP was successfully obtained. Thermogravimetric analysis indicated that QAMP was heat stable. Prior incorporation into the adhesive system, QAMP revealed an inhibition halo of 18.33?±?0.6?mm. By agar disk diffusion test, Clearfil? SE Bond containing 5% QAMP presented an inhibition halo (16.67?±?1.5?mm) similar to Clearfil? Protect Bond (positive control, 17.00?±?1.7, p?=?0.815) and significantly higher than Clearfil? SE Bond (negative control, 11.00?±?1.0, p?=?0.006). The minimum inhibitory/bactericidal concentrations for Clearfil? SE Bond containing 5% QAMP were 20?μL?mL^?1. The release of quaternary ammonium compounds from the experimental adhesive containing QAMP was very low (5.1%) when compared to Clearfil? Protect Bond that released 47.2% of its quaternary ammonium monomer (MDPB) after 30 days. The QAMP can offer enhanced antimicrobial properties for self-etching adhesive systems.     

Detection of cytokeratins in ghost cells of calcifying cystic odontogenic tumor indicates an altered keratinization and hair follicle differentiation for their development

Calcifying cystic odontogenic tumors (CCOTs) are benign cystic lesions of odontogenic origin characterized by an ameloblastoma-like epithelium and the presence of a group of cells named ghost cells. The pattern of cytokeratin (Ck) expression on these lesions remains unclear and needs to be clarified. To this end, the expression of Ck6, Ck13, Ck14, Ck18, and Ck19 in the epithelium lining of 7 cases of CCOTs was evaluated by immunohistochemistry. For this, the epithelium lining was divided into 3 distinct regions: basal layer, suprabasal layer, and the compartment composed of ghost cells. In this study, 6 cases (85.7%) were classified as type 1 and 1 (14.3%) as type 4. All cases were negative for Ck13 and Ck18, despite the epithelial layer, as well as in the ghost cells. Ck6 was only positive in the ghost cells. Positivity for Ck14 and Ck19 was found in the basal and suprabasal layers, including the ghost cells. The results showing positivity for Ck14 and Ck19 in all of the analyzed cases reinforce CCOT as being of odontogenic origin, and the restricted expression of Ck6 in the ghost cells may be indicative that these cells suffer an altered differentiation into hair follicles in CCOTs.