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Biomedical subjects

P Piombino

Publications and source records attributed to P Piombino.

7 recordsLinked to original sources

Characterization of lactic acid bacteria strains on the basis of neutral volatile compounds produced in whey.

AIMS: Seventy-eight strains of lactic acid bacteria belonging to five genera and showing six different phenotype combinations of Lac (lactose fermentation), Prt (proteolytic activity) and Cit (citrate degradation) characters were investigated for their main flavouring properties with the aim to detect variability among and within the groups. METHODS AND RESULTS: High resolution gas chromatography-mass spectrometry analysis of neutral volatile compounds produced in whey showed that, considering both neo-formation compounds and substances quantified in the whey cultures at different concentrations in comparison to the extract from sterile whey, the groups of lactococci, enterococci, thermophilic streptococci and mesophilic lactobacilli produced a higher number of volatiles than thermophilic lactobacilli and leuconostocs. Applying principal component analysis (PCA) to the results, enterococci, mesophilic lactobacilli and thermophilic streptococci showed a broad diversity, while lactococci included rather similar strains as well as strains with special flavouring properties. Applying PCA to thermophilic streptococci and enterococci, to lactococci and enterococci, to lactococci and thermophilic streptococci, or to mesophilic and thermophilic lactobacilli, the strains gathered consistently with their systematic position. CONCLUSION: The study evidenced strains producing some volatile compounds responsible for food flavouring. Flavouring properties were variable among the systematic groups and in some cases different within the same bacterial group. SIGNIFICANCE AND IMPACT OF THE STUDY: The potential of the findings is discussed with reference to the development of flavouring adjuncts for the dairy industry.

Cluster Analysis↗

Odour-impact compounds of Gorgonzola cheese.

Volatile concentrates were obtained by vacuum distillation from both natural and creamy Gorgonzola cheese and isolated by continuous liquid-liquid extraction. Both were analysed by high resolution gas chromatography (HRGC), HRGC-mass spectrometry and HRGC-olfactometry. A total of 63 components were identified in the neutral extract of the natural type (21 esters, 13 ketones, 14 alcohols, 5 aldehydes, 1 sulphur compound, 7 aromatic compounds and 2 terpenes) and 52 in the creamy type (17 esters, 12 ketones, 10 alcohols, 5 aldehydes, 1 sulphur compound, 5 aromatic compounds and 2 terpenes). Ketones, whose major components were 2-nonanone and 2-heptanone, were the predominant constituents of the neutral fraction. By olfactometric analysis of the neutral extracts, 23 odour-impact compounds were found in the natural and 21 in the creamy Gorgonzola cheese. 1-Octen-3-ol, ethyl hexanoate, 2-nonanone, 2-heptanone, 2-heptanol, ethyl butanoate, 2-nonanol and 4-methylanisole were the key odorants of the natural cheese, whereas 2-heptanone, 2-heptanol, ethyl butanoate, 3-methyl thiopropanal and an unidentified constituent with a fruity odour were characteristic of the creamy Gorgonzola cheese. On the basis of high odour unity values, 2-nonanone, 1-octen-3-ol, 2-heptanol, ethyl hexanoate, methylanisole and 2-heptanone were the most important odorants of natural and creamy Gorgonzola cheese aroma.

Animals↗

Surgical management of the neck in squamous cell carcinoma of the tongue.

If the nodes are involved, survival of patients with squamous cell carcinoma of the tongue is considerably reduced. Surgery remains the treatment of choice and, to define its role, we have reviewed 82 consecutive cases. Sixty-two cases (76%) were T1-2, and 46 patients (56%) had involved nodes. The cervical region II was the most often involved (n=26). Occult nodal metastases were present in 12 cases. The extent of nodal spread and prognosis varies according to whether the body or the base of the tongue is involved. Lesions of the base with involved node should be treated by a selective posterolateral neck dissection, whilst in the case of a lesion of the body of the tongue, the dissection should be selective anterolateral. In lesions of the base, when there are no nodes involved, a prophylactic selective posterolateral neck dissection is recommended, whilst in the case of the lesions of the body, selective supraomohyoid neck dissection in T2-4 lesions is recommended.

Adult↗

Perineural invasion of the lower alveolar nerve by oral cancer: a follow-up study of 12 cases.

Twelve previously untreated cases of oral cancer with perineural infiltration were studied retrospectively. Age, sex, site, clinical stage and outcome were evaluated. Management of the neoplasm in each case involved surgical removal and six patients required adjuvant radiotherapy. The most frequent site was the lip. At the time of diagnosis, five patients had sensory complaints and palpable lymphadenopathy was observed in three patients. The 5-year crude survival rate was 16.7%. In the cases with postoperative assessment of perineural infiltration, a median survival time of 30.8 months was observed; while in the case of preoperative assessment of nerve infiltration, extensive surgery was performed with a consequent median survival time of 44.5 months. The perineural infiltration of the lower alveolar nerve is more common (6.3%) than is generally thought. This frequency is due to the relationship with the lower lip and the mandibular region. In carcinoma of the lip, spread is generally limited to 10-15 mm along the lower alveolar nerve. In carcinoma of the mandibular region, spread is entirely dependent on the location of the tumour; the absence of clinical fixation to the bone and the small size of the carcinoma does not preclude the possibility of bone involvement. Neurological symptoms should be evaluated carefully, and a radiographic investigation of the nerve canal is mandatory.

Adult↗

Surgical management of the neck in squamous cell carcinoma of the floor of the mouth.

Nodal involvement in squamous cell carcinoma considerably lowers survival rate. Despite its importance, neck management has still not been adequately explored. The Authors have retrospectively reviewed the records of 112 cases. Unilateral N+ were treated with a homolateral therapeutic and a controlateral prophylactic neck dissection; bilateral N+ were treated with a bilateral therapeutic neck dissection. On first observation the majority of cases (66.1%) were T1-2, N+ patients accounted for 45.5%. Among N- patients, 21.3% of occult nodal metastases were observed. The 5-year survival rate was 52.7%. With N+ lesions, a radical neck dissection should be performed; the dissection should be performed bilaterally. With N- lesions a prophylactic modified radical neck dissection is recommended in T2-4 lesions.

Adult↗

Swelling of the floor of the mouth: a clinical dilemma.

Swelling of the floor of the mouth is sometime difficult to diagnose clinically. Lithiasis and neoplasm are the most frequent causes of intraoral swelling. Also after plain radiology and computed tomography the diagnosis is often dubious. A case of swelling of the floor of the mouth due to an adenoid cystic carcinoma of the sublingual gland is reported.

Biopsy, Needle↗