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Rifamycin derivs., such as I [R is hydrogen or acetyl R1 and R2 are independently selected from the group consisting of hydrogen, ( C1-​4) alkyl, benzyloxy, mono- and di-​(C1-​3) alkylamino-​(C1-​4)​alkyl, (C1-​3)​alkoxy, (C1-​4) alkyl, hydroxy-​Me, hydroxy-​(C2-​4)​-​alkyl, and nitro or R1R2 taken together with two consecutive carbon atoms of the pyridine nucleus form a benzene ring optionally substituted by one or two Me or Et groups and R3 is hydroxyalkyl (C1-​4)​]​, were prepd. for use in antibacterial pharmaceutical compns. The prepd. rifamycin derivs. were claimed for use in the prevention, treatment or amelioration of bacterial overgrowth in a patient suffering from a bowel related disorder, such as irritable bowel syndrome, travelers' diarrhea, small intestinal bacterial overgrowth, Crohn's disease, chronic pancreatitis, pancreatic insufficiency, hepatic encephalopathy, diverticulitis, enteritis or colitis. These rifamycin derivs. may be used optionally in combination with one or more addnl. antibiotics, such as rifamycin, or rifaximin. Thus, rifamycin deriv. I [R = COMe, R1 = 4-​Me, R2 = H, R3 = CH2OH] was prepd. via a cyclocondensation reaction of the corresponding cyclic acetal II with 2-​amino-​4-​methylpyridine. The cyclic acetal II was prepd. by a fermn. process mediated by Nocardia mediterranea. The prepd. rifamycin derivs. were evaluated in vitro for antibacterial activity against a panel of pathogenic bacterium, such as E. coli (ATCC 25922)​, P. aeruginosa (ATCC 27853) and E. faecalis (ATCC 259212)​. Pharmaceutical formulations for the delivery of these rifamycin derivs. were presented.

Crystalline polymorphous forms of rifaximin (INN) antibiotic named rifaximin alpha and rifaximin beta, and a poorly crystalline form named rifaximin gamma, useful in the production of medicinal preparations containing rifaximin for oral and topical use and obtained by means of a crystallization carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a determinate temperature and for a determinate period of time, followed by a drying carried out under controlled conditions until reaching a settled water content in the end product, are the object of the invention.

Crystalline polymorphous forms of rifaximin (INN) antibiotic named rifaximin alpha and rifaximin beta, and a poorly crystalline form named rifaximin gamma, useful in the production of medicinal preparations containing rifaximin for oral and topical use and obtained by means of a crystallization carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a determinate temperature and for a determinate period of time, followed by a drying carried out under controlled conditions until reaching a settled water content in the end product, are the object of the invention.

Forms of rifaximin (INN) antibiotic, such as the poorly crystalline form named rifaximin gamma are described, along with the production of medicinal preparations containing rifaximin for oral and topical use.

The present invention relates to rifaximin polymorphic forms a, b and g, the processes for their prepn. and the use thereof in the manuf. of medicinal prepns. for the oral or topical route. A hydroalcoholic suspension of 5 g of rifaximin g was heated at 40 Deg for 24 h, the suspension was then filtered and the solid was washed with water, then dried under vacuum at room temp. until const. wt. 4 g of rifaximin was obtained, showing a powder X-ray diffractogram corresponding to that of the polymorphic form a and a water content equal to 2.6%.

Carbon footprint reduction of paving materials could be explored through recycling mining by-products into different applications, which will preserve natural resources and decrease environmental issues. One possible approach is to reuse quarry dust and mining ore waste as precursors in geopolymer applications. geopolymers are mineral polymers rich in aluminosilicates with an amorphous to a semi-crystalline three-dimensional structure. The current review aims to summarize the studies conducted during the past decade on geopolymers containing quarry dust and mine tailings. The first section discusses various precursors used for geopolymer cement production such as metakaolin, ground granulated blast furnace slag (GGBFS), fly ash, and quarry/mining ore wastes including silt, tungsten, vanadium, copper, gold, zinc, marble, iron, basalt, and lithium. Different calcination treatments and curing conditions have been summarized. In some cases, the precursors are required to be calcined to increase their reactivity. Both ambient temperature and elevated temperature curing conditions have been summarized. Less attention has been paid to room temperature curing, which is necessary for field and industrial implementations. Engineering properties such as compressive strength, density, durability and acid resistance, water absorption and abrasion of geopolymers containing mining waste were reviewed. One of the main barriers preventing the widespread use of waste powders, in addition to economic aspects, in geopolymers could be due to their unstable chemical structure. This was shown through extensive leachate of Na+ or K+ cations in geopolymer structures. The review of over 100 articles indicated the need for further research on different aspects of quarry waste geopolymer productions before its full industrial implementation.

HBV vaccine needs 3 injections over 6 months to induce immunity. Thus, the use of adjuvants capable of inducing earlier immune protection would be highly desirable. Most adjuvants may act by inducing cytokines, and among them, type I interferons (IFNs), deserve a special attention in view of the potent immunomostimulatory activity observed in mouse models and on dendritic cell functions. The aim of the present trial was to evaluate the effects of IFN-alpha administered as an adjuvant of HBV vaccine in healthy unvaccinated individuals. No significant enhancing effect on the antibody response was observed, in spite of an early and transient upregulation of costimulatory molecule expression on peripheral blood mononuclear cells, which may be suggestive of an IFN-mediated activation of antigen presenting cells. We conclude that, under the conditions used in this trial, natural IFN-alpha does not act as an adjuvant of the HBV vaccine in healthy unvaccinated individuals.