Diffuse Kaposi sarcoma with oral involvement in a person diagnosed with human immunodeficiency virus/acquired immune deficiency syndrome: A case report

Kaposi's sarcoma is a well-known multifocal vascular tumor initially described by pathologist Moritz Kaposi. This report presents the case of a 38-year-old bisexual male who consulted the infectious diseases department with non-itchy maculopapular and purpuric lesions on the skin with the involvement of the oral mucosa, suggesting a diagnosis of Kaposi's sarcoma. Biological and radiological investigations were performed. The patient was found to be human immunodeficiency virus positive with a viral load of 251.000/mL and a CD4 count of 182/mm3. In addition, secondary syphilis was diagnosed. Histopathological examinations confirmed HHV-8 KS. The patient was treated with Extencilline® and antiretroviral therapy. After 10 months of chemotherapy, a favorable outcome was noted with complete resolution of skin and oral mucosa lesions.

Salivary biochemical parameters in people living with HIV on ART and dental caries: a cross-sectional study in Monastir, Tunisia

BACKGROUND

Studies regarding salivary biochemical parameters and dental caries in adult people living with HIV/AIDS (PLWHA) are scanty.

AIM

To investigate salivary biochemical parameters and dental caries in adult PLWHA who are on antiretroviral therapy (ART) and compare the findings with people negative for HIV infection.

METHODS

The study included 50 HIV positive individuals as a test group (TG) and 50 HIV negative individuals as a control group (CG). Dental examination was performed according to WHO guidelines to assess DMFT. Digital panoramic radiographs were taken to detect additional infectious foci. Non-stimulated saliva was collected between 9 and 12 a. m for 5 min to evaluate 18 biochemical parameters and salivary flow rate (SFR). Parametric and non parametric tests were used according to data distribution. The level of significance was set at p < 0.05%.

RESULTS

Patients' mean ages and M/F sex ratios for TG and CG were 38.80 ± 9.69 y/o. vs. 37.98 ± 13.47 y/o. and 3.54 vs. 2.33, respectively. Higher means of decayed teeth were recorded in TG, 4.47 ± 3.00 vs. 3.88 ± 2.81 in CG with no significant difference (p = 0.41). Means of filled teeth were significantly lower in TG 2.38 ± 2.16 vs. 4.16 ± 3.35 in CG (p = 0.01), respectively. No statistical significant difference was noted in DMFT indices between the 2 groups (8.04 ± 6.90 vs. 8.52 ± 6.24, p = 0.71). The following salivary parameters were significantly lower in TG compared to CG, respectively: mean SFR 0.44 ± 0.18 ml/min vs. 0.61 ± 0.26 ml/min; median levels of sodium and chlorides, 4 mmol/L and 13.5 mmol/L vs. 9 mmol/L and 19 mmol/L (p < 0.001) and uric acid, 103.50 mmol/L vs. 163 (p = 0.009). However, higher median levels were recorded with calcium, 1.09 mmol/L vs. 0.54 (p < 0.001) and sIgA 23 mg/dl vs. 5 mg/dl (p < 0.001). In TG, a positive correlation was found between DC, potassium, urea, and chlorides (p < 0.05). Salivary renal and hepatic biomarkers were comparable between the two groups.

CONCLUSIONS

PLWHA have shown an alteration in some salivary parameters, more decayed teeth and less filled teeth. Preventive measures should be implemented to lower dental caries and enhance accessibility to oral care services. In addition, saliva can be utilized to monitor oral and general health status among PLWHA on ART.

Gold Nanostar Characterization by Nanoparticle Tracking Analysis

We demonstrate the application of nanoparticle tracking analysis (NTA) for the quantitative characterization of gold nanostars (GNSs). GNSs were synthesized by the seed-mediated growth method using triblock copolymer (TBP) gold nanoparticles (GNPs). These GNPs (≈ 10 nm) were synthesized from Au³⁺ (≈ 1 mM) in aqueous F127 (w/v 5%) containing the co-reductant ascorbic acid (≈ 2 mM). The GNS tip-to-core aspect ratio (AR) decreased when higher concentrations of GNPs were added to the growth solution. The AR dependency of GNSs on Au³⁺/Au(seed) concentration ratio implies that growth is partly under kinetic control. NTA measured GNS sizes, concentrations, and relative scattering intensities. Molar absorption coefficients ∼ 10⁹-10¹⁰ M^-1 cm^-1 (ε_400 nm) for each batch of GNSs were determined using the combination of extinction spectra and NTA concentrations for heterogeneous samples. NTA in combination with UV-vis was used to derive the linear relationships: (1) hydrodynamic size versus localized surface plasmon peak maxima; (2) ε_400 nm versus localized surface plasmon peak maxima; (3) ε_400 nm versus hydrodynamic size. NTA for quantitative characterization of anisotropic nanoparticles could lead to future applications, including heterogeneous colloidal catalysis.

Periodontal pathogens promote cancer aggressivity via TLR/MyD88 triggered activation of Integrin/FAK signaling that is therapeutically reversible by a probiotic bacteriocin

Epidemiological studies reveal significant associations between periodontitis and oral cancer. However, knowledge about the contribution of periodontal pathogens to oral cancer and potential regulatory mechanisms involved is limited. Previously, we showed that nisin, a bacteriocin and commonly used food preservative, reduced oral cancer tumorigenesis and extended the life expectancy in tumor-bearing mice. In addition, nisin has antimicrobial effects on key periodontal pathogens. Thus, the purpose of this study was to test the hypothesis that key periodontal pathogens (Porphyromonas gingivalis, Treponema denticola, and Fusobacterium nucleatum) promote oral cancer via specific host-bacterial interactions, and that bacteriocin/nisin therapy may modulate these responses. All three periodontal pathogens enhanced oral squamous cell carcinoma (OSCC) cell migration, invasion, tumorsphere formation, and tumorigenesis in vivo, without significantly affecting cell proliferation or apoptosis. In contrast, oral commensal bacteria did not affect OSCC cell migration. Pathogen-enhanced OSCC cell migration was mediated via integrin alpha V and FAK activation, since stably blocking alpha V or FAK expression abrogated these effects. Nisin inhibited these pathogen-mediated processes. Further, Treponema denticola induced TLR2 and 4 and MyD88 expression. Stable suppression of MyD88 significantly inhibited Treponema denticola-induced FAK activation and abrogated pathogen-induced migration. Together, these data demonstrate that periodontal pathogens contribute to a highly aggressive cancer phenotype via crosstalk between TLR/MyD88 and integrin/FAK signaling. Nisin can modulate these pathogen-mediated effects, and thus has therapeutic potential as an antimicrobial and anti-tumorigenic agent.

Effect of Flavonoid Supplementation on Alveolar Bone Healing-A Randomized Pilot Trial

We investigated the effects of two common dietary supplements on bone healing in dental extraction sockets in humans. In this randomized pilot trial, male subjects took Grape Seed Extract [GSE] or Grapefruit Extract [GFE] starting two weeks prior to dental extraction and maintained this regimen for sixty days after surgery. Extraction sockets were filled with a collagen plug. After 24 h, a socket sample was collected and processed for quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) and an 84-gene wound healing assay. Sixty days after tooth extraction, a core of newly formed bone was obtained prior to dental implant placement and processed for histology. qRT-PCR revealed that GFE led to a significant decrease in platelet-derived growth factor and interleukin (IL)1-β compared to GSE, and a significant decrease in IL-6 and CXCL2 compared to control. GSE led to a significant increase in coagulation factor Von Willebrand and inflammatory marker IL1-β compared to GFE. WISP1 and CXCL5 were upregulated in both groups. Overall, GFE showed a downregulation of inflammation and GSE led to a decrease in collagen density and increased osteoclasts. This pilot trial highlights the need for further investigation on the mechanism of action of such supplements on bone healing and oral health.

Localized Delivery of Amifostine Enhances Salivary Gland Radioprotection

Radiotherapy for head and neck cancers commonly causes damage to salivary gland tissue, resulting in xerostomia (dry mouth) and numerous adverse medical and quality-of-life issues. Amifostine is the only Food and Drug Administration-approved radioprotective drug used clinically to prevent xerostomia. However, systemic administration of amifostine is limited by severe side effects, including rapid decrease in blood pressure (hypotension), nausea, and a narrow therapeutic window. In this study, we demonstrate that retroductal delivery of amifostine and its active metabolite, WR-1065, to murine submandibular glands prior to a single radiation dose of 15 Gy maintained gland function and significantly increased acinar cell survival. Furthermore, in vivo stimulated saliva secretion was maintained in retrograde-treated groups at levels significantly higher than irradiated-only and systemically treated groups. In contrast to intravenous injections, retroductal delivery of WR-1065 or amifostine significantly attenuated hypotension. We conclude that localized delivery to salivary glands markedly improves radioprotection at the cellular level, as well as mitigates the adverse side effects associated with systemic administration. These results support the further development of a localized delivery system that would be compatible with the fractionated dose regimen used clinically.