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1.
J Dairy Sci ; 102(12): 10799-10813, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31521346

ABSTRACT

Spore formers are common spoilage-causing microorganisms in dairy products; however, their modes of spoilage (proteolysis, lipolysis, etc.) have not been described in detail for cultured dairy products such as sour cream and yogurt. The objective of the present study was to test the ability of spore-forming strains isolated from dairy environments for their spoilage-causing activities at typical sour cream (24°C) and yogurt (42°C) fermentation temperatures. A total of 25 spore-forming strains were isolated from different sources, including raw milk, pasteurizer balance tank, biofilms formed on heat exchangers, and milk powder. These strains were tested for proteolytic and lipolytic activities and for their ability to degrade phospholipids, common stabilizers (starch, gelatin, xanthan gum, pectin), and exopolysaccharides (EPS) at sour cream and yogurt fermentation temperatures. A higher percentage of positive strains was observed for selected activities at yogurt fermentation temperature compared with sour cream fermentation temperature. Identified proteolytic spore-forming strains, based on a skim milk agar method, were subsequently quantified for their level of proteolysis using non-casein nitrogen (NCN) content and sodium dodecyl sulfate-PAGE (SDS-PAGE). The proteolytic strains that showed the highest levels of proteolysis (highest percentages of NCN content) at 24°C were Bacillus mojavensis BC, Bacillus cereus DBC, Bacillus subtilis DBC, B. mojavensis DBC1, and Paenibacillus polymyxa DBC1. At 42°C the strains with the highest levels of proteolysis (highest percentages of NCN content) were B. subtilis DBC, B. mojavensis BC, B. mojavensis DBC1, B. cereus DBC, and Bacillus licheniformis DBC6. Results of SDS-PAGE demonstrated that proteolytic strains had primarily hydrolyzed ß- and κ-CN. A viscometric method was used to evaluate the susceptibility of exopolysaccharides (EPS) to degradation by selected spore formers. This method helped to determine that EPS produced by commercial yogurt and sour cream cultures is susceptible to degradation by spore formers present in dairy environments.


Subject(s)
Bacillus/metabolism , Milk Proteins/metabolism , Milk/microbiology , Phospholipids/metabolism , Animals , Fermentation , Food Microbiology , Milk/metabolism , Paenibacillus/metabolism , Pasteurization , Spores , Temperature , Yogurt/microbiology
2.
J Dairy Sci ; 101(3): 1864-1871, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29331472

ABSTRACT

Innovative clean label processes employed in the manufacture of acid gels are targeted to modify the structure of proteins that contribute to rheological properties. In the present study, CO2-treated milk protein concentrate powder with 80% protein in dry matter (TMPC80) was mixed with nonfat dry milk (NDM) in different ratios for the manufacture of acid gels. Dispersions of NDM and TMPC80 that provided 100, 90, 70, and 40% of protein from NDM were reconstituted to 4.0% (wt/wt) protein and 12.0% (wt/wt) total solids. Dispersions were adjusted to pH 6.5, followed by heat treatment at 90°C for 10 min. Glucono-δ-lactone was added and samples were incubated at 30°C, reaching pH 4.5 ± 0.05 after 4 h of incubation. Glucono-δ-lactone levels were adjusted to compensate for the lower buffering capacity of samples with higher proportions of TMPC80, which is attributable to the depletion of buffering minerals from both the serum and micellar phase during preparation of TMPC80. Sodium dodecyl sulfate-PAGE analysis indicated a higher amount of caseins in the supernatant of unheated suspensions with increasing proportions of CO2-treated TMPC80, attributable to the partial disruption of casein micelles in TMPC80. Heat treatment reduced the level of whey proteins in the supernatant due to the heat-induced association of whey proteins with casein micelles, the extent of which was larger in samples containing more micellar casein (i.e., samples with a lower proportion of TMPC80). Particle size analysis showed only small differences between nonheated and heated dispersions. Gelation pH increased from ˜5.1 to ˜5.3, and the storage modulus of the gels at pH 4.5 increased from ˜300 to ˜420 Pa when the proportion of protein contributed by TMPC80 increased from 0 to 60%. Water-holding capacity also increased and gel porosity decreased with increasing proportion of protein contributed by TMPC80. The observed gel properties were in line with microstructural observations by confocal microscopy, wherein sample gels containing increasing levels of TMPC80 exhibited smaller, well-connected aggregates with uniform, homogeneous pore sizes. We concluded that TMPC80 can be used to partially replace NDM as a protein source to improve rheological and water-holding properties in acid gels. The resultant gels also exhibited decreased buffering, which can improve the productive capacity of yogurt manufacturing plants. Overall, the process can be leveraged to reduce the amount of hydrocolloids added to improve yogurt consistency and water-holding capacity, thus providing a path to meet consumer expectations of clean label products.


Subject(s)
Gels/chemistry , Milk Proteins/chemistry , Animals , Caseins/analysis , Gluconates/chemistry , Hydrogen-Ion Concentration , Lactones/chemistry , Micelles , Milk/chemistry , Rheology
3.
Indian J Pharm Sci ; 72(6): 732-7, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21969745

ABSTRACT

Diclofenac sodium and alginate was intercalated into montmorillonite to form uniform sized beads by gelation method. The structure and surface morphology of the synthesized composite beads were characterized by powdered X-ray diffraction, Fourier transform infrared spectroscopy, thermo gravimetric analysis and scanning electron microscopy. Diclofenac release kinetics of the composite in simulated intestinal fluid medium (pH 7.4) and effect of montmorillonite content on the in vitro release of diclofenac from diclofenac-montmorillonite-alginate composites bead was investigated by UV/Vis spectrophotometer. Diclofenac encapsulation efficiency in the montmorillonite-alginate composites bead increases with an increase in the montmorillonite content. The control release of diclofenac from diclofenac-montmorillonite-alginate composites beads was observed to be better as compared to diclofenac-alginate beads.

4.
Article in English | MEDLINE | ID: mdl-20952926

ABSTRACT

Fifty cases with chronic idiopathic urticaria of more than 3 months duration were selected and divided into two groups. Group 'A' was given 10 mg loratadine once daily, while group 'B' was given pheniramine maleate 25 mg, twice daily for one month. All patients were followed for one month more. 48% excellent response was observed in group 'A' while 16% excellent response was observed in group 'B'. Good response was observed in 24% of patients in group 'A', while in group 'B' 16% of patients had good response. No side effects were observed in loratadine group, while drowsiness was observed in pheniramine group.

5.
Science ; 266(5187): 1035-9, 1994 Nov 11.
Article in English | MEDLINE | ID: mdl-7973656

ABSTRACT

Two of four proteins that associated with translocation intermediates during protein import across the outer chloroplast envelope membrane were identified as guanosine triphosphate (GTP)-binding proteins. Both proteins are integral membrane proteins of the outer chloroplast membrane, and both are partially exposed on the chloroplast surface where they were accessible to thermolysin digestion. Engagement of the outer membrane's import machinery by an import substrate was inhibited by slowly hydrolyzable or non-hydrolyzable GTP analogs. Thus, these GTP-binding proteins may function in protein import into chloroplasts.


Subject(s)
Chloroplasts/metabolism , GTP-Binding Proteins/metabolism , Intracellular Membranes/metabolism , Membrane Proteins/metabolism , Monomeric GTP-Binding Proteins , Plant Proteins/metabolism , Adenosine Triphosphate/metabolism , Amino Acid Sequence , Base Sequence , Biological Transport , Chloroplasts/chemistry , GTP-Binding Proteins/analysis , GTP-Binding Proteins/chemistry , Guanosine Triphosphate/metabolism , Intracellular Membranes/chemistry , Membrane Proteins/analysis , Membrane Proteins/chemistry , Molecular Sequence Data , Plant Proteins/chemistry , Sequence Alignment
6.
Brain Behav Immun ; 5(4): 328-38, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1777727

ABSTRACT

The immunomodulatory action of corticosteroids and the ability of central noradrenergic systems to activate the hypothalamic-pituitary-adrenal (HPA) axis led us to investigate the relationship between neuroendocrine status and the clinical course of encephalomyelitis (EAE) following adrenalectomy and depletion of noradrenaline (NA) centrally or peripherally. A significant inverse correlation was found between hypothalamic NA and serum corticosterone (CS) at peak clinical signs of EAE in all the sham groups or when NA was depleted only in the peripheral nervous system. A positive correlation was found between serum CS and disease severity, and in all experimental groups with intact peripheral and/or central noradrenergic pathways a uniformly increased splenic NA content was also observed at peak disease. Administration of 6-OHDA i.p. to neonatal or adult Lewis rats produced a significant depletion of splenic NA alone which resulted in increased disease severity, despite the fact that circulating CS was elevated. Thus the rise in the NA content of lymphoid tissue at peak clinical signs contributes to recovery. A single i.c.v. injection of 6-OHDA into the hypothalamic region resulted in an 80% reduction in NA content, which subsequently modified the clinical severity of EAE. Serum CS levels rose preclinically in the treated group and remained high despite milder clinical disease than that seen in the sham group. The overriding immunoregulatory influence of glucocorticoids is demonstrated by the rapid onset of clinical EAE and morbidity in adrenalectomized animals. However, the strong inverse correlation found between hypothalamic NA and circulating CS indicates that regulation of the HPA axis may ultimately be controlled by central sympathetic pathways.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental/physiopathology , Hypothalamus/physiology , Neuroimmunomodulation/physiology , Norepinephrine/physiology , Adrenal Glands/physiopathology , Adrenalectomy , Animals , Corticosterone/blood , Encephalomyelitis, Autoimmune, Experimental/immunology , Female , Hypothalamo-Hypophyseal System/physiopathology , Oxidopamine/toxicity , Rats , Rats, Inbred Lew , Spleen/chemistry , Spleen/immunology , Sympathectomy, Chemical
7.
Brain ; 114 ( Pt 2): 1013-23, 1991 Apr.
Article in English | MEDLINE | ID: mdl-2043938

ABSTRACT

Postmortem unfixed whole brains from 17 multiple sclerosis and 6 control cases were examined by magnetic resonance imaging (MRI) using a T2-weighted spin echo sequence and histology to determine the relationship between areas of abnormal MRI signal and underlying pathological change. In group 1, small MRI lesions and correspondingly small plaques, most of which were chronic, were detected histologically in 5 brains. In 4 brains there were more extensive areas of both abnormal signal and histological plaques which were more often active (group 2). However, in a further 5 brains extensive MRI abnormalities were observed when only small periventricular plaques were present histologically (group 3). Lesions in the hindbrain and cerebral grey matter were infrequently observed by MRI. The extensive MRI abnormalities seen in areas in which only small histological plaques were found may be the result of vascular permeability changes in the normal-appearing white matter surrounding plaques.


Subject(s)
Brain/pathology , Multiple Sclerosis/pathology , Autopsy , Humans , Middle Aged , Occipital Lobe/pathology , Parietal Lobe/pathology , Periaqueductal Gray/pathology , Reference Values , Rhombencephalon/pathology
8.
J Neuroimmunol ; 26(2): 183-6, 1990 Feb.
Article in English | MEDLINE | ID: mdl-1688880

ABSTRACT

When experimental autoimmune encephalomyelitis (EAE) is induced by adoptive transfer of myelin basic protein (MBP)-specific lymphocytes the splenic noradrenergic and adrenocortical responses mirror in most respects those that occur following sensitization with spinal cord and Freund's adjuvant (CFA), despite the absence of the primary immune challenge. An early drop in splenic noradrenaline (NA), observed only when purified protein derivative-primed cells are transferred may reflect a vigorous proliferative response in vitro, not observed with MBP-specific cells. However, serum corticosterone (CS) levels and the density of splenocyte beta-adrenergic receptors were increased in both experimental groups within 3 days of cell inoculation. The stress of clinical signs of EAE resulted in highly significant increases in both splenic NA and plasma CS. Thus adoptively transferred EAE provides a well-delineated model of autoimmune disease for investigating the immunomodulatory role of the neural and endocrine systems.


Subject(s)
Adrenal Cortex/metabolism , Encephalomyelitis, Autoimmune, Experimental/metabolism , Immunization, Passive , Norepinephrine/metabolism , Spleen/metabolism , Animals , Corticosterone/blood , Corticosterone/pharmacology , Encephalomyelitis, Autoimmune, Experimental/blood , Encephalomyelitis, Autoimmune, Experimental/immunology , Female , Immunization , Lymphocytes/metabolism , Myelin Basic Protein/immunology , Rats , Rats, Inbred Lew , Receptors, Adrenergic, beta/metabolism , Spleen/cytology , Spleen/transplantation , Time Factors
9.
Br J Orthod ; 17(1): 21-8, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2310736

ABSTRACT

Orthodontic treatment decisions when maxillary central incisors are absent or are of poor prognosis, are discussed. Autotransplantation of mandibular first premolars to the incisor region is suggested as an approach in selected cases. The literature is reviewed, surgical technique described and case selection summarized. Cases are reported where autotransplantation of premolars to the maxillary incisor region has produced good functional and aesthetic results.


Subject(s)
Bicuspid/transplantation , Incisor , Space Maintenance, Orthodontic , Adolescent , Female , Humans , Male , Malocclusion, Angle Class II/surgery , Maxilla/surgery , Root Resorption/surgery , Tooth Movement Techniques , Transplantation, Autologous/methods
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