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At least 217 records · Page 12Linked to original sources
PubMed2001

Applications of pectinases in the commercial sector: a review.

Pectinases are one of the upcoming enzymes of fruit and textile industries. These enzymes break down complex polysaccharides of plant tissues into simpler molecules like galacturonic acids. The role of acidic pectinases in bringing down the cloudiness and bitterness of fruit juices is well established. Recently, there has been a good number of reports on the application of alkaline pectinases in the textile industry for the retting and degumming of fiber crops, production of good quality paper, fermentation of coffee and tea, oil extractions and treatment of pectic waste water. This review discusses various types of pectinases and their applications in the commercial sector.

Beverages↗
PubMed2005

The Medi-RIVAGE study: reduction of cardiovascular disease risk factors after a 3-mo intervention with a Mediterranean-type diet or a low-fat diet.

BACKGROUND: Epidemiologic studies link Mediterranean-type diets to a low incidence of cardiovascular disease; however, few dietary intervention studies have been undertaken, especially in primary prevention. OBJECTIVES: In the Mediterranean Diet, Cardiovascular Risks and Gene Polymorphisms (Medi-RIVAGE) study, the effects of a Mediterranean-type diet (Med group) or a low-fat diet (low-fat group) on risk factors were evaluated in 212 volunteers (men and women) with moderate risk factors for cardiovascular disease. DESIGN: After the 3-mo dietary intervention, changes in many risk factors were evaluated. Dietary questionnaires and plasma nutritional markers were used to test compliance. RESULTS: Although the dietary goals were only partially reached, changes in dietary habits were observed in both groups (n = 169): protein, carbohydrate, and fiber intakes increased and fat quality (decreased saturated fat and increased monounsaturated or polyunsaturated fat) improved. BMI, total and triacylglycerol-rich lipoprotein (TRL) cholesterol, triacylglycerols, TRL triacylglycerols, apolipoproteins A-I and B, insulinemia, glycemia, and the homeostasis model assessment score were significantly lower after 3 mo. The reductions in total cholesterol, triacylglycerols, and insulinemia remained significant after adjustment for BMI. There was a trend for a diet-by-time interaction for LDL cholesterol (P = 0.09). Our data predicted a 9% reduction in cardiovascular disease risk with the low-fat diet and a 15% reduction with this particular Mediterranean diet. CONCLUSION: After a 3-mo intervention, both diets significantly reduced cardiovascular disease risk factors to an overall comparable extent.

Adolescent↗
PubMed1994

Constipation in the elderly: influence of dietary, psychological, and physiological factors.

OBJECTIVE: To identify dietary, psychological, and physiological characteristics of older individuals with chronic constipation, compared with a control group of individuals without constipation, and identify correlates of colonic transit time. DESIGN: Cohort study. SETTING: University hospital and affiliated clinics. PARTICIPANTS: Eighteen constipated and 18 control subjects who were nondemented, ambulatory, community-dwelling outpatients over the age of 60 years. MEASURES: Measures included a 1-week food diary, diet questionnaire, bowel diary, the Hopkins Symptom Checklist (SCL-90R), colonic transit study, and medical history, including queries about activity, medications, medical illnesses, and bowel symptoms. MAIN RESULTS: Constipated subjects reported consuming fewer meals per day compared with control subjects (P < 0.01) and a tendency to consume fewer calories (P = 0.07). There were no differences between groups on fiber or fluid intake or any of the other dietary parameters. However, slow colonic transit was significantly related to low caloric intake (P < 0.0001), higher percent of protein in the diet (P < 0.05), low fluid intake (P < 0.05), and to psychological symptoms of somatization, obsessive-compulsiveness, depression, anxiety, and the global severity index (P < 0.05). Transit times were unrelated to crude or dietary fiber intake, activity level, or age. CONCLUSIONS: The data suggest that constipation in this older population is related to caloric intake rather than fiber consumption or other dietary qualities. Psychological distress is associated with slowed colonic transit and should be investigated further as a possible etiologic factor in constipation.

Aged↗
PubMed1980

Intracellular structures of Mycoplasma pneumoniae revealed after membrane removal.

Mycoplasma pneumoniae was grown on Formvar- and carbon-coated electron microscope grids and treated with the nonionic detergent Triton X-100 to gently remove the membrane and cytoplasm. The detergent mixture was composed of 0.5% Triton X-100 in SSR-2 broth base. After this treatment, the grids were rinsed in a mixture of 0.1 M KCl, 5 mM MgCl2, and 6 mM potassium phosphate buffer (pH 7.05) and negatively stained with uranyl acetate. The Triton X-100-resistant remains of M. pneumoniae after gentle removal of the membrane and cytoplasm consisted of fibrous structures oriented similarly to the undisrupted cells. The thin fibers displayed a negative staining quality and diameter analogous to that of rabbit muscle F-actin. The fibrous moieties ended in rodlike condensations which appeared striated in negatively stained and shadowed preparations. These striations were regular, and the majority of rod structures had lengths of 220 to 300 nm and widths of 50 to 80 nm. Specific antibody to rabbit muscle actin, produced in guinea pigs, was used in indirect immunofluorescence of the M. pneumoniae colonies. Fluorescence was detected, with concentrations at the colony center and at the tips of filamentous cells.

Actins↗
PubMedDate not supplied

Headaches and sinus disease: the endoscopic approach.

Headaches can be of sinugenic origin even if this cause may not be suspected from the case history. Endoscopy of the lateral nasal wall with rigid cold light endoscopes in combination with polytomography or computed tomography usually will reveal the underlying causes hidden from the unaided eye, the operating microscope, and standard x-ray examination. Small lesions in the lesser cells of the ethmoid complex may give rise to headaches, especially when located in the key areas of the ethmoid infundibulum or frontal recess. Many anatomic variations of the structures in the middle meatus can narrow the stenotic clefts even more and thus predispose to more or less intense contact of opposing mucosal surfaces. This may impede or block ventilation and drainage of the ethmoid and surrounding larger sinuses and thus affect those as well. After identification of these underlying causes, functional endoscopic sinus surgery with usually minimal operations often can provide dramatic relief of symptoms that may have been present for months or even years. The neuropeptides recently were newly identified as a group of mediators besides the neurotransmitters noradrenalin and acetylcholine. Substance P (SP) is one of the most important neuropeptides that we can identify in the human nasal mucosa. It mediates pain impulses to the cortex via afferent C fibers. Simultaneously from polymodal receptors in the nasal mucosa, local reflexes are mediated by SP via an axon reflex, causing vasodilatation, plasma extravasation ("neurogenic edema"), and hypersecretion. The receptors can be stimulated by chemical and caloric irritants and also mechanical irritants such as pressure. The pressure exerted on nasal mucosa by polyps or mucosal swelling due to other reasons in the ethmoid clefts, cells, and narrow spaces apparently can be enough to trigger an SP-mediated pain sensation via afferent C fibers. Over the axon reflex an initially small lesion may lead in a vicious circle to quite significant symptoms. The model of "referred pain" explains why the pain is not necessarily felt at its origin, but may be projected onto corresponding dermatomes. The pain-mediating function of SP can be blocked selectively by capsaicin, the pungent component of red pepper, which leads to desensitization of the receptors and degeneration of the afferent C fibers without affecting other sensory qualities. In patients with vasomotor rhinitis we were able to block all the patients' symptoms including headaches by topical administration of capsaicin. After identification of underlying causes with endoscopy and CT, lesions and contact areas should be operated upon if medical treatment fails.(ABSTRACT TRUNCATED AT 400 WORDS)

Capsaicin↗
PubMed1993

A histochemical ATPase method for the demonstration of the muscle capillary network.

A histochemical method for demonstration of the capillaries in skeletal muscle of birds is proposed. The present method, which is a modification of a previously reported myosin ATPase technique used for simultaneous staining of capillaries and fiber types, provides an accurate count of capillaries associated with different fiber types in avian skeletal muscles. We have applied the original and the modified method to serial adjacent sections of certain skeletal muscles and our results show that after the application of the original technique: (a) in muscles having dark Type II fibers, these fibers produce a masking effect on their adjacent capillaries; (b) a consistent and significant undercounting in capillary densities can be seen even in muscles having no dark Type II fibers; and (c) the staining quality and capillary count are substantially improved with the use of the modified method. We attribute the better results obtained with our modification to differences in thermosensitivity of ATPase activity from the capillary endothelium and of the myofibers. A mathematical treatment is therefore proposed to correct the values of capillary count obtained with the original method.

Analysis of Variance↗
PubMed1999

[Transmission and scanning microscopy of elastofibroma ultrastructure].

Elastofibroma is a rare benign tumor of soft tissues that has the elective localization in peri- or interscapular region. It is characterized by the proliferation of fibroblast-like cells which appear enveloped by abundant elastic and collagen fibers. Here we present a case of elastofibroma, observed in a 63 year old woman in the interscapular region. The neoformation has been studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Our hypothesis is the possibility that elastofibroma is the consequence of active neoformation of fibers elastic normal in the quality that subsequently is meet to progressive degenerative phenomenons.

Female↗
PubMed1980

Three-dimensional observation of the temporomandibular joint disk in the rhesus monkey.

The three-dimensional ultrastructure of the TMJ disk of two normal rhesus monkeys was investigated using the SEM. The upper and under surface of the TMJ disk consists of a close network of delicate collagen fibrils. On the undersurface, they have an undulating configuration, with the elevations running in one direction. On the upper surface, irregular and gentle waves can be observed. The matrix of the TMJ disk is composed of two main parts: one is the collagen fibrils that run in a sagittal direction making up the central fibrous core, and the other consists of the collagen fibrils that enclose the fibrous core. The collagen fibrils running in a sagittal direction show a wavy, winding appearance, and these structures are more numerous on the side of the TMJ disk facing the condyle. It is concluded that the wavy, winding structure and undulated configuration of the collagen fibers results in an elastic quality, opposes stress, and functions to absorb shock.

Animals↗
PubMed1998

Psychophysical study of stinging pain evoked by brief freezing of superficial skin and ensuing short-lasting changes in sensations of cool and cold pain.

Psychophysical methods were used to investigate pain in human subjects elicited by controlled freezing of the skin using a novel vortex thermode. When cooling stimuli delivered with a small thermode (7 mm diameter) exceeded the normal cold pain threshold into the sub-zero temperature range (-5 to -11 degrees C), all subjects reported an intense, sharp stinging pain sensation which occurred suddenly and was readily differentiated from normal cold pain. The onset of this stinging 'freezing' pain was closely correlated with a sudden increase in skin temperature beneath the thermode of 4.77+/-0.86 degrees C (+/-SD) associated with the phase transition of supercooled water to ice. The mean intensity of freezing pain was rated as 1.7 times as intense as cold pain at threshold. Subjects' mean reaction-time latency to signal stinging pain following the onset of phase transition on the volar forearm was 687+/-220 ms, which was slower than that for mechanically evoked impact pain. Freezing pain is suggested to be mediated by A-delta fibers, based on estimates of conduction velocity and on the observation that the freezing pain took on a burning quality of slower onset during an A-fiber pressure block of nerve fibers. We also investigated changes in skin sensation following the freezing stimulus, and found that freezing led to (a) an immediate, significant decrease in the cold pain threshold (to higher temperatures), which recovered to baseline in < 16 min, (b) a concomitant change in the quality of cold pain from dull to burning, (c) a significant, parallel increase in the threshold for the perception of cooling (to lower temperatures) which frequently manifested as a complete loss of cold sensation, and (d) a mild heat pain hyperalgesia which was still present 24 h later. The changes in thermal sensitivity were not accompanied by consistent changes in mechanical sensitivity. These results indicate that a characteristic sharp, stinging pain is reliably evoked abruptly at the phase transition of supercooled skin water to ice The ensuing brief decrease in cold pain threshold with burning quality, coupled with decreased sensitivity to cold, are speculated to reflect a central disinhibition of C-fiber nociceptor input due to reduced cold fiber activity. These effects may be relevant to frostbite, and distinguish themselves from the more pronounced thermal and mechanical hyperalgesia seen following intense freeze lesion of the skin.

Adult↗
PubMed2000

Comparison of clinical performance, histology and single-fiber contractility in free neurovascular muscle flaps.

The aim of this study was to obtain further insights about muscle regeneration processes in free neurovascular flaps. In cases of insufficient functional return of muscle strength, several factors, such as diminished axonal ingrowth, fatty degeneration, or connective tissue proliferation are discussed. In the study, free neurovascular latissimus dorsi (LD) flaps were examined after a regeneration period of 2 to 6 years. Clinical function (M1 to M4) and histopathologic characteristics of the muscle grafts were correlated. The rare instances of secondary procedures, such as tenolysis or scar correction, were used for biopsies of the muscle graft. Free neurovascular LD flaps were examined after a regeneration period between 2 and 6 years. The grafted LD was compared to normal, healthy LD muscle. Normal LD muscle showed a typical homogeneous pattern of types 1 and 2 fibers in a ratio of almost 1:1. No significant differences concerning fiber distribution and fiber diameters in three anatomic areas of the LD (proximal, medial, caudal) could be detected. After regeneration, the authors found the following: type grouping of muscle fiber types, fiber splitting, and groups of hypertrophic and atrophic fibers. Most of the muscle fibers were not reinnervated by axons and were atrophic or degenerated. The essential proliferation of connective and fatty tissue was absent. Normal and hypertrophic fibers were found mainly in the muscle grafts with good clinical results. In muscle grafts with good contraction force (M4), 46 percent of reinnervated muscle fibers were found; M3 contractility was correlated with 31 percent of reinnervated muscle fibers; M2 with 24 percent; and M1 with 21 percent of reinnervated fibers. The force of a free muscle graft seems to depend mainly on the quality of nerve regeneration. Characteristics of the muscle fiber itself were not examined extensively, because the single-fiber contractility of the regenerated fibers was similar to the contractility of normal, healthy fibers.

Adult↗
PubMed1994

Bitter taste in single chorda tympani taste fibers from chimpanzee.

We have found earlier that chimpanzee chorda tympani taste fibers fall into groups that conform with the human taste qualities. This study focuses on bitter taste and its relation to sweet taste. Eight fibers were classified as bitter fibers according to their responses to 31 stimuli. The stimuli included the bitter compounds quinine, denatonium benzoate and caffeine. The results indicate a clear dichotomy between the bitter and sweet fibers. Sweet fibers never responded to the bitter compounds. However, in addition to their responses to the above compounds, some of the bitter fibers were stimulated by other compounds. Most prominent were responses to NaCl-amiloride mixture, KCl and xylitol. In most cases the cause could be assumed to be a bitter taste in the compound. These results suggest that the bitter and sweet tastes are conveyed in specific and separate groups of nerve fibers in the chimpanzee. Because of the closeness between chimpanzee and human, this finding has implications on the question of taste coding in human and the concept of taste qualities.

Animals↗
PubMed2003

A bioassay for methylated galacturonan on pulp-fiber surfaces.

A colorimetric bioassay has been developed enabling separation of wood pulp qualities based on the quantity of methyl-esterified galacturonan exposed on fiber surfaces. Thermomechanical pulp (TMP) and chemi-TMP (CTMP) had, respectively, 3.1 and 0.7 microg galacturonan on the surface per mg wood pulp. The presence of galacturonan on the surface of TMP and CTMP was further confirmed by immunogold localization.

Colorimetry↗
PubMed2000

Neuromuscular specializations of the pharyngeal dilator muscles: II. Compartmentalization of the canine genioglossus muscle.

The genioglossus (GG) muscle is divided into horizontal and oblique compartments that are the main protrusor and depressor muscles of the tongue, respectively. In humans the GG plays an important role in speech articulation, swallowing, and inspiratory dilation of the pharynx. At present, little is known about the neuromuscular specializations of the GG in any mammal. This study examined the specializations of these compartments in the canine tongue using a variety of anatomical and histochemical techniques. Six canine GG muscles were sectioned and stained for myofibrillar ATPase to study muscle fiber types; five whole-mount GG muscles were stained for acetylcholinesterase (AChE) to study the distribution of motor endplates; and eight whole mount GG muscles were processed with Sihler's stain to study the entire nerve supply pattern. In addition, the arrangement of muscle fibers of the GG within the tongue was also determined (N = 3). The most notable difference between the compartments of the GG was their proportions of fast and slow twitch muscle fibers: the horizontal compartment contained 64% slow twitch muscle fibers compared to 41% in the oblique compartment. In addition, although the oblique compartment appeared to be grossly homogeneous, it could be divided into thirds by significant differences in the percentages of slow twitch fibers: posterior (23%), middle (15%), and anterior (56%; P < 0.05). The muscle fibers of the oblique GG within the tongue were found to be divided into medial and lateral layers that run vertically and transversely, respectively. The nerve supply to each third of the oblique GG formed a plexus with the anterior third being the densest. The innervation pattern of the oblique GG was also notable as terminal nerve branches coursing parallel to the muscle fascicles gave off perpendicular secondary branches along each motor endplate band. These secondary nerve branches connected the primary nerves and formed a regularly spaced grid throughout the compartment. Evidently, the two compartments of the GG exhibited different anatomical specializations. The horizontal had a slow muscle fiber profile and simple innervation pattern; these qualities are possibly related to its single force vector and respiratory related activity. The oblique compartment had a relatively fast muscle fiber profile with evidence for three separate functional subdivisions. The most anterior part was noticeably different, and was presumably specialized for fine motor control of the tip of the tongue. The vertically oriented fibers of the oblique GG within the tongue body may function as a midline depressor of the tongue, whereas its transversely oriented fibers could play a role in narrowing the tongue during other motor tasks.

Acetylcholinesterase↗
PubMedDate not supplied

Neuronal cell types and taste quality coding.

Over the past 25 years, there have been two opposing views of how taste information is represented in the activity of gustatory neurons. One view, the across-fiber pattern (AFP) theory, postulates that taste quality is represented by the pattern of activity across the afferent population. Stimuli with similar tastes produce similar patterns of activity. The other view is that activity in a few distinct neuron types codes taste quality in a "labeled-line" fashion. Neurons responding best to sucrose, for example, would represent "sweetness," and those responding best to NaCl would code "saltiness." Some of these neuron types appear to have a biological significance, such as the NaCl-best cells, which receive input about sodium stimuli exclusively from an amiloride-sensitive epithelial ion channel. However, the relatively broad tuning of these neurons makes it unlikely that they are capable of unambiguously coding information about taste quality. Rather, these neuron types play a critical role in establishing unique AFPs that distinguish among taste stimuli. The relative activity across these cell types represent taste quality, much like the patterns of activity across broadly tuned photoreceptors code information about stimulus wavelength.

Animals↗
PubMed2005

Survival analysis of Escherichia coli encapsulated in a hollow fiber membrane in vitro and in vivo: preliminary report.

The purpose of the observations was the viability and quality evaluation of E. coli bacteria encapsulated in hollow fiber membranes (HF) in short in vivo and in vitro experiments. A polypropylene, surface-modified hollow fiber was applied for immunoisolation of E. coli bacteria transfected with a green fluorescent protein (E. coli GFPI). The presence of GFP fluorescence of organisms was assessed with the use of flow cytometry. The E. coli GFPIs were then observed for the period of 5 days in in vitro experiments in the culture medium. A single IPTG (isopropyl beta-D-1-thiogalactopyranoside) induction of GFP gene appeared to be adequate for an expression of GFP protein for 5 days. The GFP expression values observed for E. coli GFPs encapsulated in HF during culture in different culture media were comparable. The survival of E. coli GFPIs encapsulated in HF after 1, 2, 4, or 5 days of subcutaneous implantation into mice was evaluated. The explanted E. coli GFPIs exhibited mean expression 603 +/- 17 (n = 32) units of fluorescence during the implantation period. The values obtained were comparable for selected days of observation. It was observed that the membranes applied ensured the bacteria growth within the HF's space only.

Animals↗
PubMed2006

Mechanical and physical properties of carbon-graphite fiber-reinforced polymers intended for implant suprastructures.

OBJECTIVES: Mechanical properties and quality of fiber/matrix adhesion of poly(methyl methacrylate) (PMMA)-based materials, reinforced with carbon-graphite (CG) fibers that are able to remain in a plastic state until polymerization, were examined. METHODS: Tubes of cleaned braided CG fibers were treated with a sizing resin. Two resin mixtures, resin A and resin B, stable in the fluid state and containing different cross-linking agents, were reinforced with CG fiber loadings of 24, 36, and 47 wt% (20, 29, and 38 vol.%). In addition, resin B was reinforced with 58 wt% (47 vol.%). After heat-polymerization, flexural strength and modulus were evaluated, both dry and after water storage. Coefficient of thermal expansion, longitudinally and in the transverse direction of the specimens, was determined. Adhesion between fibers and matrix was evaluated with scanning electron microscopy (SEM). RESULTS: Flexural properties and linear coefficient of thermal expansion were similar for both fiber composites. With increased fiber loading, flexural properties increased. For 47 wt% fibers in polymer A the flexural strength was 547.7 (28.12) MPa and for polymer B 563.3 (89.24) MPa when water saturated. Linear coefficient of thermal expansion was for 47 wt% CG fiber-reinforced polymers; -2.5 x 10(-6) degrees C-1 longitudinally and 62.4 x 10(-6) degrees C-1 in the transverse direction of the specimens. SEM revealed good adhesion between fibers and matrix. More porosity was observed with fiber loading of 58 wt%. CONCLUSIONS: The fiber treatment and the developed resin matrices resulted in good adhesion between CG fibers and matrix. The properties observed indicate a potential for implant-retained prostheses.

Carbon↗
PubMed1990

Temperature effects on auditory nerve fiber response in the American bullfrog.

Single fiber recordings were made from auditory nerve fibers of the American bullfrog (Rana catesbeiana). As temperature was raised: (1) Best frequencies of fibers from the amphibian papilla (N = 15) increased. Below 600 Hz best frequency changes up to 0.06 oct/degrees C were found; above 600 Hz changes were less than 0.03 oct/degrees C. In the basilar papilla (N = 4) no significant increase of best frequency was found. (2) Spike rates in response to fixed-RMS-amplitude stimuli increased considerably: Q10 of spike rate ranged from 5 to 10. (3) Spontaneous activity, found in basilar papilla fibers, increased with average Q10 = 1.6 (+/- 0.3). (4) A conspicuous change of tuning quality factor Q10 dB was only observed in two fibers, that were taken to low temperatures (less than 16 degrees C). (5) the nearly linear frequency vs. phase relation in amphibian papilla shifts to higher frequency (along with shift of best frequency), while its average slope remains nearly unchanged.

Action Potentials↗
PubMed2006

Fiber for the treatment of hemorrhoids complications: a systematic review and meta-analysis.

OBJECTIVES: To evaluate the impact of laxatives on a wide range of symptoms in patients with symptomatic hemorrhoids. METHODS: We searched using the following sources: MEDLINE, EMBASE, CINAHL and CENTRAL, BIOSIS, AMED, Papers First and Proceedings; study authors, industry, and experts in the field. We included all published and unpublished parallel group randomized controlled trials comparing any type of laxative to placebo or no therapy in patients with symptomatic hemorrhoids. Two reviewers independently screened studies for inclusion, retrieved all potentially relevant studies, and extracted data on study population, intervention, prespecified outcomes, and methodology. RESULTS: Seven trials randomized 378 patients to fiber or a nonfiber control. Studies were of moderate quality for most outcomes. Meta-analyses using random effects models suggested that fiber has an apparent beneficial effect. The risk of not improving/persisting symptoms decreased by 47% in the fiber group (RR = 0.53, 95% CI 0.38-0.73) and the risk of bleeding by 50% (RR = 0.50, 95% CI 0.28-0.89). Studies with multiple follow-ups, usually at 6 wk and at 3 months, showed consistent results over time. Results are also compatible with large treatment effects in prolapse, pain, and itching, but even in the pooled analyses confidence intervals were wide and compatible with no effect (RR = 0.79, 95% CI 0.37-1.67; RR = 0.33, 95% CI 0.07-1.65; and RR = 0.71, 95% CI 0.24-2.10, respectively). One study suggested a decrease in recurrence. Results showed a nonsignificant trend toward increases in mild adverse events in the fiber group (RR = 6.0, 95% CI 0.57-64.8). CONCLUSIONS: Trials of fiber show a consistent beneficial effect for symptoms and bleeding in the treatment of symptomatic hemorrhoids.

Constipation↗