A TaqMan minor groove binder probe-based quantitative reverse transcription polymerase chain reaction for detection and quantification of chikungunya virus

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus with widespread distribution across the globe. Since 2016, CHIKV re-emerged in several countries including Indian subcontinent and Southeast Asia. A proper diagnostic tool for early diagnosis of CHIKV infection is crucial to facilitate patient management and control virus transmission at the earliest stage of outbreak. Therefore, a TaqMan minor groove binder (MGB) probe-based quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay was developed to detect and quantify the CHIKV. The primers and probe were designed based on a conserved genomic region of 730 global CHIKV sequences that is located between nsP1 and nsP2 genes. The nucleotide mismatches of primers and probe with 730 global CHIKV sequences and 13 alphaviruses were then analysed in silico. In this study, the last 5 nucleotides at 3' end of primers and 5' end of probe were considered to be the critical regions for priming. In silico analysis revealed that the critical regions of primers and probe were at least 99.6% matched with the 730 global CHIKV sequences. Besides, the primers and probe showed at least 5/20 (25.0%) and 4/17 (23.5%) nucleotide mismatches with 13 alphaviruses respectively. The amplification efficiency of qRT-PCR assay was 100.59% (95% CI= 93.06, 109.33) with a R2 score of 0.957. Its limit of detection (LOD) at 95% probability level was 16.6 CHIKV RNA copies (95% CI= 12.9, 28.9). The qRT-PCR assay was specific to CHIKV without cross-reacting with all dengue virus serotypes, Getah virus, Tembusu virus and Zika virus. The diagnostic results of qRT-PCR assay were perfectly agreed (k=1.000, p=0.003) with a commercial trioplex assay, with sensitivity of 100% (95% CI= 61, 100) and specificity of 100% (95% CI= 44, 100). Overall, the developed qRT-PCR assay is ideal for rapid, sensitive and specific detection as well as quantification of CHIKV.

COVID-related mucormycosis mimicking dental infection

A recent increase in the prevalence of mucormycosis of the head and neck in patients who have recovered from COVID-19 following hospitalization has been reported. A Majority of the cases have been reported from India. Conditions such as diabetes mellitus, use of corticosteroids for other autoimmune conditions, organ transplant, immunosuppression, immunodeficiency, and malignancies especially hematologic ones, are all known risk factors for mucormycosis. Recently, hospitalization for COVID-19 has been added to the list of risk factors for opportunistic mucormycosis infection. This is likely attributable to the high doses and prolonged use of corticosteroids in the treatment of hospitalized COVID-19 patients. Case Description: Two patients with post-COVID-19 associated rhinocerebral mucormycosis presented with profound unexplained dental disease including tooth mobility and dental abscess mimicking periodontal disease. The patients were previously hospitalized for COVID-19 and received prolonged treatment with high doses of corticosteroids. The patients responded well to the surgical debridement with or without antifungal therapy. Conclusion: Oral healthcare providers including oral and maxillofacial surgeons, dentists, dental hygienists, and other dental practitioners can play a vital role in the recognition and early diagnosis of rhinocerebral mucormycosis given the large number of patients with severe COVID-19 infection who have recovered following hospitalization and/or received long-term high doses of immunosuppressive treatment.

Development of a TaqMan minor groove binding probe-based quantitative reverse transcription polymerase chain reaction for the detection and quantification of Zika virus

Zika virus (ZIKV) infection has emerged as a global health concern following epidemic outbreaks of severe neurological disorders reported in Pacific and Americas since 2016. Therefore, a rapid, sensitive and specific diagnostic test for ZIKV infection is critical for the appropriate patient management and the control of disease spread. A TaqMan minor groove binding (MGB) probe-based quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay was developed based on the conserved sequence regions of 463 ZIKV NS2B genes. The designed ZIKV qRT-PCR assay was evaluated for its detection limit, strain coverage and cross-reactivity. We further assessed the clinical applicability of qRT-PCR assay for ZIKV RNA detection using a total 18 simulated clinical specimens. The detection limit of the qRT-PCR assay was 11.276 ZIKV RNA copies at the 95% probability level (probit analysis, p<= 0.05). Both Asian and African ZIKV strains were detected by the qRT-PCR assay without cross-reacting with DENV-1, DENV-2, DENV-3, DENV-4, CHIKV, JEV, LGTV, GETV and SINV. The qRT-PCR assay demonstrated a perfect agreement (k = 1.000, P < 0.001) with the reference assay; the sensitivity and specificity of the qRT-PCR assay were 100% (95% CI= 79.6-100) and 100% (95% CI= 43.9-100) respectively. The qRT-PCR assay developed in this study is a useful diagnostic tool for the broad coverage detection and quantification of both the Asian and African ZIKV strains.

A Co-Association of Streptococcus mutans and Veillonella parvula/dispar in Root Caries Patients and In Vitro Biofilms

Root caries in geriatric patients is a growing problem as more people are maintaining their natural teeth into advanced age. We determined the levels of various bacterial species previously implicated in root caries disease or health using quantitative real-time PCR in a pilot study of 7 patients with 1 to 4 root caries lesions per person. Levels of 12 different species on diseased roots compared to healthy (contralateral control) roots were measured. Four species were found at significantly higher levels on diseased roots (Streptococcus mutans, Veillonella parvula/dispar, Actinomyces naeslundii/viscosus, and Capnocytophaga granulosa) compared across all plaque samples. The level of colonization by these species varied dramatically (up to 1,000-fold) between patients, indicating different patients have different bacteria contributing to root caries disease. Neither of the two species previously reported to correlate with healthy roots (C. granulosa and Delftia acidovorans) showed statistically significant protective roles in our population, although D. acidovorans showed a trend toward higher levels on healthy teeth (P = 0.08). There was a significant positive correlation between higher levels of S. mutans and V. parvula/dispar on the same diseased teeth. In vitro mixed biofilm studies demonstrated that co-culturing S. mutans and V. parvula leads to a 50 to 150% increase in sucrose-dependent biofilm mass compared to S. mutans alone, depending on the growth conditions, while V. parvula alone did not form in vitro biofilms. The presence of V. parvula also decreased the acidification of S. mutans biofilms when grown in artificial saliva and enhanced the health of mixed biofilms.

Leiomyosarcoma of the Nasal Cavity and Paranasal Sinuses: A Case Report and Comprehensive Review of the Literature

Sinonasal leiomyosarcoma (LMS) is a rare and aggressive mesenchymal tumor with smooth muscle differentiation. The sinonasal tract is an unusual primary site for LMS, as scant smooth muscle exists in this location, with only 75 cases reported in the English literature including the case presented herein. Sinonasal LMS is considered an aggressive head and neck tumor with significant potential for recurrence and metastasis. Since recurrence is high and the potential for late metastasis exists, lifelong follow-up in these patients would be beneficial, especially among those with previous history of RB.

Adenomatoid odontogenic tumor: a series of 28 cases from a biopsy service

OBJECTIVE

Adenomatoid odontogenic tumor (AOT) is a benign odontogenic tumor with an excellent prognosis, often seen in children and young adults. The aim was to examine the spectrum of clinical, radiographic, and histologic attributes of AOT and assess clinician recognition of this entity. In addition, diagnostic considerations and treatment modalities were explored.

METHOD AND MATERIALS

With Institutional Review Board approval, archival cases of AOT from the University of Florida Oral Pathology Biopsy Service (1994-2019) were examined. Clinical and demographic data along with accompanying radiographs and original slides were reviewed.

RESULTS

A total of 28 cases of AOT were identified. These were all solitary in nature, with a mean age of 20.6 years (range 12-67 years). Most patients were under 20 (75.0%) with a definite female predilection (64.3%). Anterior jaws remained the most common location (85.2%), with a higher maxillary predilection (57.1%). Clinical impression included odontogenic lesions such as dentigerous cyst, lateral periodontal cyst, and odontogenic keratocyst.

CONCLUSION

The spectrum of features of AOT is described. As clinicians were unfamiliar with AOT, highly characteristic features of AOT and more unique variants are discussed extensively to improve diagnostic aptitude. Clinicians must remain aware of this entity, as treatment is minimal compared to other odontogenic entities.

Peripheral ameloblastic fibro-odontoma-Report of 2 cases of a very rare entity

Ameloblastic fibro-odontoma (AFO) is a rare benign mixed odontogenic tumor that affects children and young adults. AFO occurs mainly intraosseous. Extraosseous AFO is extremely rare. We report 2 cases of rare peripheral ameloblastic fibro-odontoma in 2- and 12-year-old female patients. Microscopic examination revealed a benign proliferation of odontogenic epithelium associated with a dentinoid material distributed within a cell-rich mesenchymal stroma resembling dental papilla. Simple surgical excision of the lesion is usually curative. There was no recurrence after a short period of follow-up. Clinicians should be cognizant of this rare entity, which can be considered in a differential diagnosis of gingival growths that are noted in early childhood.

IL-10 and IL-12B gene polymorphisms in a multiethnic Malaysian population

Inheritance of polymorphisms in the interleukin (IL)-10 promoter and IL-12B genes, which influence cytokine production and activities, may define the balance in T helper response in infection and autoimmune diseases. In the present study, we investigated the distribution of the IL-10 promoter and IL-12B gene polymorphisms in a multiethnic Malaysian population. Overall, our findings suggest that the IL-12B and IL-10 -592 genotypes were distributed homogenously across all major ethnic groups, including Malays, Chinese, and Indians, except for polymorphisms at IL-10 -1082. At this gene locus, the ethnic Chinese showed a significantly lower allele frequency of -1082G (2.1%) compared to the Malay (12.2%) and Indian (15.3%) populations. Results for the IL-12B and IL-10 gene polymorphisms were consistent with those reported for the Asian population, but markedly different from those of the African and Caucasian populations. Our findings suggest that there are specific genetic variations between different ethnic groups, which should be examined in all gene population-based association studies.

A novel rare copy number variant of the ABCF1 gene identified among dengue fever patients from Peninsular Malaysia

Copy number variation (CNV) is a form of genetic variation in addition to single nucleotide polymorphisms. The significance of CNV in the manifestation of a number of diseases is only recently receiving considerable attention. We genotyped 163 dengue patients from Peninsular Malaysia for genes possibly linked to dengue infection using quantitative real-time PCR. Here, we report a serendipitous discovery of a novel rare CNV of the ABCF1 gene among the dengue patients. Among these patients, two had a gain of 1 copy (CN = 3) and one had lost 1 copy (CN = 1), indicating that a rare CNV of the ABCF1 gene was detected among dengue patients from Peninsular Malaysia. Although the gene is suspected to regulate inflammatory responses and pathogen-induced cytokine storm, its relevance to dengue requires further investigation.