Loss of Y-chromosome does not correlate with age at onset of head and neck carcinoma: a case-control study

Loss of Y-chromosome has been correlated with older age in males. Furthermore, current evidence indicates that Y-chromosome loss also occurs in several human tumors, including head and neck carcinomas. However, the association between Y nullisomy and the occurrence of neoplasias in elderly men has not been well established. In the present study, the association between Y-chromosome loss and head and neck carcinomas was evaluated by comparison to cells from peripheral blood lymphocytes and normal mucosa of cancer-free individuals matched for age using dual-color fluorescence in situ hybridization. Twenty-one patients ranging in age from 28 to 68 years were divided into five-year groups for comparison with 16 cancer-free individuals matched for age. The medical records of all patients were examined to obtain clinical and histopathological data. None of the patients had undergone radiotherapy or chemotherapy before surgery. In all groups, the frequency of Y-chromosome loss was higher among patients than among normal reference subjects (P < 0.0001) and was not age-dependent. These data suggest that Y-chromosome loss is a tumor-specific alteration not associated with advanced age in head and neck carcinomas.

Negative correlation between phospholipase and esterase activity produced by Fusarium isolates

Fusarium species have emerged as one of the more outstanding groups of clinically important filamentous fungi, causing localized and life-threatening invasive infections with high morbidity and mortality. The ability to produce different types of hydrolytic enzymes is thought to be an important virulence mechanism of fungal pathogens and could be associated with the environment of the microorganism. Here, we have measured the production of two distinct lipolytic enzymes, phospholipase and esterase, by sixteen Fusarium isolates recovered from the hospital environment, immunocompromised patients’ blood cultures, foot interdigital space scrapings from immunocompromised patients, and foot interdigital space scrapings from immunocompetent patients (4 isolates each). Fourteen of these 16 isolates were identified asFusarium solani species complex (FSSC) and two were identified as F. oxysporum species complex (FOSC). Some relevant genus characteristics were visualized by light and electron microscopy such as curved and multicelled macroconidia with 3 or 4 septa, microconidia, phialides, and abundant chlamydospores. All Fusarium isolates were able to produce esterase and phospholipase under the experimental conditions. However, a negative correlation was observed between these two enzymes, indicating that a Fusarium isolate with high phospholipase activity has low esterase activity and vice versa. In addition, Fusarium isolated from clinical material produced more phospholipases, while environmental strains produced more esterases. These observations may be correlated with the different types of substrates that these fungi need to degrade during their nutrition processes.

Impact of HPV infection on the development of head and neck cancer

Human papillomavirus (HPV)-related head and neck squamous cell carcinoma (HNSCC) is considered to be a distinct clinical entity with better prognosis than the classical tobacco- and alcohol-associated tumors. The increasing incidence of this neoplasia during the last decades highlights the need to better understand the role of HPV in the development of these cancers. Although the proportion of HNSCC attributed to HPV varies considerably according to anatomical site, overall approximately 25% of all HNSCC are HPV-DNA positive, and HPV-16 is by far the most prevalent type. In this review we discuss the existing evidence for a causal association between HPV infection and HNSCC at diverse anatomical head and neck subsites.

Relationship of inflammatory markers and pain in patients with head and neck cancer prior to anticancer therapy

Pain is a common symptom in patients with cancer, including those with head and neck cancer (HNC). While studies suggest an association between chronic inflammation and pain, levels of inflammatory cytokines, such as C-reactive protein (CRP) and tumor necrosis factor-alpha (TNF-α), have not been correlated with pain in HNC patients who are not currently undergoing anticancer treatment. The purpose of this study was to examine the relationship between these inflammatory markers and perceived pain in HNC patients prior to anticancer therapy. The study group consisted of 127 HNC patients and 9 healthy controls. Pain was assessed using the Brief Pain Inventory (BPI), and serum levels of CRP and TNF-α were determined using the particle-enhanced turbidimetric immunoassay (PETIA) and ELISA techniques, respectively. Patients experiencing pain had significantly higher levels of CRP (P<0.01) and TNF-α (P<0.05) compared with controls and with patients reporting no pain. There were significantly positive associations between pain, CRP level, and tumor stage. This is the first study to report a positive association between perceived pain and CRP in HNC patients at the time of diagnosis. The current findings suggest important associations between pain and inflammatory processes in HNC patients, with potential implications for future treatment strategies.

Head Space Solid Phase Micro-Extraction (HS - SPME) of volatile organic compounds produced by Sporidiobolus salmonicolor (CBS 2636)

The aim of the present study was the assessment of volatile organic compounds produced by Sporidiobolus salmonicolor (CBS 2636) using methyl and ethyl ricinoleate, ricinoleic acid and castor oil as precursors. The analysis of the volatile organic compounds was carried out using Head Space Solid Phase Micro-Extraction (HS - SPME). Factorial experimental design was used for investigating extraction conditions, verifying stirring rate (0-400 rpm), temperature (25-60 ºC), extraction time (10-30 minutes), and sample volume (2-3 mL). The identification of volatile organic compounds was carried out by Gas Chromatography with Mass Spectrum Detector (GC/MSD). The conditions that resulted in maximum extraction were: 60 ºC, 10 minutes extraction, no stirring, sample volume of 2.0 mL, and addition of saturated KCl (1:10 v/v). In the bio-production of volatile organic compounds the effect of stirring rate (120-200 rpm), temperature (23-33 ºC), pH (4.0-8.0), precursor concentration (0.02-0.1%), mannitol (0-6%), and asparagine concentration (0-0.2%) was investigated. The bio-production at 28 ºC, 160 rpm, pH 6,0 and with the addition of 0.02% ricinoleic acid to the medium yielded the highest production of VOCs, identified as 1,4-butanediol, 1,2,2-trimethylciclopropilamine, beta-ionone; 2,3-butanodione, pentanal, tetradecane, 2-isononenal, 4-octen-3-one, propanoic acid, and octadecane.

Use of the polymerase chain reaction for detection of Fusarium graminearum in bulgur wheat

The detection of mycotoxigenic fungi in foodstuff is important because their presence may indicate the possible associated mycotoxin contamination. Fusarium graminearum is a wheat pathogen and a producer of micotoxins. The polymerase chain reaction (PCR) has been employed for the specific identification of F. graminearum. However, this methodology has not been commonly used for detection of F. graminearum in food. Thus, the objective of the present study was to develop a molecular methodology to detect F. graminearum in commercial samples of bulgur wheat. Two methods were tested. In the first method, a sample of this cereal was contaminated with F. graminearum mycelia. The genomic DNA was extracted from this mixture and used in a F. graminearum specific PCR reaction. The F. graminearum species was detected only in samples that were heavily contaminated. In the second method, samples of bulgur wheat were inoculated on a solid medium, and isolates having F. graminearum culture characteristics were obtained. The DNA extracted from these isolates was tested in F. graminearum specific PCR reactions. An isolate obtained had its trichothecene genotype identified by PCR. The established methodology could be used in surveys of food contamination with F. graminearum.

Fusarium graminearum growth inhibition mechanism using phenolic compounds from Spirulina sp

The application of natural antifungal substances is motivated by the need for alternatives to existing methods that are not always applicable, efficient, or that do not pose risk to consumers or the environment. Furthermore, studies on the behaviour of toxigenic species in the presence of natural fungicides have enabled their safe application in the food chain In this study, Spirulina LEB-18 phenolic extract was assessed for its antifungal activity on 12 toxigenic strains of Fusarium graminearum isolated from barley and wheat. The susceptible metabolic pathways were assessed through the determination of structural compounds (glucosamine and ergosterol) and enzyme activity of the microorganisms' primary metabolism. The results indicate that phenolic extracts reduced the growth rate of the toxigenic species investigated. The IC50 was obtained by applying 3 to 8% (p/p) of phenolic compounds in relation to the culture medium. The use of this natural fungicide proved promising for the inhibition of fungal multiplication, especially in terms of the inactivation of enzymatic systems (amylase and protease) of Fusarium graminearum.