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A new thermophilic, cellulolytic species of the genus Clostridium was isolated from riverside mud. The guanine-plus-cytosine content of its DNA is 34 mol%. The isolate ferments a wide range of carbohydrates. Its major fermentation products are ethanol, butanol, acetate, butyrate, lactate, carbon dioxide, and hydrogen. Hydrogen sulfide is also produced. The name Clostridium thermupapyrulyticum is proposed. The type strain has been deposited in the South American Biotechnology and Applied Microbiology microbiological resource center (United Nations Educational, Scientific, and Cultural Organization) culture collection, Tucuman, Argentina, as UBA 305.The genus Clostridium includes four cellulolytic and thermophilic species: Clostridium thermocellum (lo), C. stercorarium (8), C. thermolacticum (7), and C. thermocopriae (5).Thermophilic bacteria are of particular interest for the industrial conversion of cellulose to liquid fuels. For this reason, we searched for cellulolytic thermophiles in different anaerobic environments.One isolate from riverside mud digested cellulose and fermented a wide range of carbohydrates. This isolate was chosen for further studies. In this article, we present its taxonomic features and propose it as a new species named Clostridiurn thermopapyrolyticum . MATERIALS AND METHODSMedia and culture conditions. CM4 (2) was the basal medium used throughout this study. This medium was supplemented with carbon sources as indicated below. Cellulose powder (standard grade; Whatman, Maidstone, England) and strips of Whatman no. 1 filter paper were used as cellulosic substrates. Solid medium contained 1.5% (wthol) agar (Merck, Darmstadt, Germany). The Hungate method (4) was used for liquid cultures. The headspace gas was oxygen-free nitrogen. The cultures were plated either in an anaerobic hood (Coy Laboratory Products, Ann Arbor, Mich.) in an atmosphere of 80% N,-10% H,-10% CO, or on a laboratory bench. In the latter case, the plates were incubated in anaerobic jars at 60°C with anaerobiosis generators (Anaerocult; Merck).Isolation procedure and stock culture maintenance. Onehalf-gram samples of mud were added to 5 ml of liquid medium containing a filter paper strip (1 by 5 cm) as the sole carbon source and incubated at 60°C until the strip was degraded. The cultures were then vigorously shaken and streaked onto plates supplemented with 0.6% (wthol) cellobiose. After 48 h of incubation, isolated colonies were restreaked and repicked twice on the same medium. The purified colonies were transferred to liquid CM4 containing a filter paper strip of the same size as that mentioned above with no other carbon source. After complete paper degradation, the cultures were plated on cellobiose agar. The whole * Corresponding author. procedure was repeated once more. Stock cultures were kept at 4°C in medium containing a strip of filter paper. This stock was used as an inoculum for the cultures used to perform the physical and biochemical assays described below. All assays were done in triplicate.Temperature studi...

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Severe periodontal disease (SPD) associated with systemic peripheral inflammation, cognitive impairment (CI) and arterial stiffness (AS) has been recognized. The aim of this study was to investigate whether CI and arterial stiffness (AS) occur in cardiovascular disease (CVD) patients with SPD. A crosssectional case-control study included hospitalized patients with CVD. Demographic characteristics, CVD and atherogenic risk factors were recorded. SPD was diagnosed by clinical and radiographic dental examinations. Dental clinical attachment level (CAL) and CAL % were recorded. A Mini-Mental State Examination test (MMSE) assessed cognition, a MMSE score of < 27 was set as the cut-off point of CI; a score ≥ 27 was considered as no CI. Patients were categorized into: MMSE< 27 in the three models. The risk of having MMSE < 27 increased an average of 2.404-fold for each 1-unit increase in PWV. SPD and AS had significant and independent associations on the risk for development CI. MMSE negatively correlated with CAL% (r=0.69) and PWV (r=0.70). PWV positively correlated with CAL% (r=0.67). Serum VCAM-1 levels were higher in SPD with lower MMSE scores. In conclusion, SPD increases the risk of development of cognitive decline in CVD patients. PWV was directly associated with the risk of cognitive decline. These findings denote a significant opportunity to improve periodontal health in order to avert CI in CVD patients.