Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
1.
Environ Anal Health Toxicol ; 38(2): e2023014-0, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37933108

ABSTRACT

The experimental studies of Aluminum Phosphide (AP) poisoning in rats revealed several clinical and pathological signs such as hemorrhage, sinusoidal dilatation, bile stasis, centrilobular necrosis, Kupffer cell hyperplasia, infiltration by mononuclear cells, and fatty infiltration in the liver tissues. This paper aimed to show the impact of carrots on the toxic effect of AP on the livers of adult rats (female). To investigate some biochemical and histopathological changes effects of AP in rats, sixty white female rats were equally divided into four groups, the first group (G1) was administered orally with 3mg/kg/ body weight of AP, the second group (G2) was orally treated with AP and 10% carrot extract at the same time. The third group (G3) administrated 10% carrot extract only. The fourth (G4) group was the negative control and was treated with distilled water only. The experiments continued for a month at the animal house of the Veterinary Medicine College of Baghdad University. The results revealed that high levels of liver enzymes and bilirubin were induced in G1 with decreasing total protein levels. The pathological examination revealed the presence of marked proliferation of Kupffer cells in G1 livers. However, the G2 group showed slight infiltration of lymphocytes in sinusoids. The pathological changes in the livers of G3 group showed slight cloudy swelling in hepatocytes compared with the normal texture of hepatocytes in G4. The data of this experiment showed that treatment with carrot extract significantly decreases the elevation in the level of liver function enzymes in animal poisoned with AP. In addition, treatment with carrot extract reduces the severe damage in the hepatic tissue that occurred in rats treated with AP only. In general, it could be concluded that treatment with carrot extract provides a remedial effect against the hepatotoxicity that is resulted from exposure to AP.

2.
Br Dent J ; 220(3): 117-20, 2016 Feb 12.
Article in English | MEDLINE | ID: mdl-26868800

ABSTRACT

AIM: This paper aims to compare the effectiveness of articaine buccal infiltrations (BIs) and lidocaine inferior alveolar nerve blocks (IANBs) for inducing pulpal anaesthesia in mandibular molars. METHOD: Studies which compared articaine BIs with lidocaine IANBs were identified by completing a full literature search using the MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials databases. Only studies that used permanent mandibular molars were included. Two papers were accepted for appraisal. RESULTS: It was found that 55.6-69.2% and 65.4-70.4% of lidocaine IANBs and articaine BIs were successful, respectively. Neither study was able to determine a significant difference between the two techniques. CONCLUSIONS: Articaine BIs are no more effective than lidocaine IANBs and the decision of which method to practice should be based on patient selection, cost and time efficiency. The studies present a number of weaknesses in their design, hence, the level of evidence they provide is inconclusive. Further investigation in this field is warranted.


Subject(s)
Anesthesia, Dental/methods , Anesthetics, Local , Carticaine , Lidocaine , Nerve Block/methods , Administration, Buccal , Anesthesia, Local/methods , Anesthetics, Local/administration & dosage , Carticaine/administration & dosage , Humans , Lidocaine/administration & dosage , Mandibular Nerve
3.
Br Dent J ; 218(6): 333-5, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25812881

ABSTRACT

In the last of this series of articles, the author will review some of the current interventions and advice that is most commonly used before and following endodontic surgical procedures. The aim of this article is to review the current evidence in the literature to support or refute current practices, management methods and protocols. The relative strength of the research discussed - including strengths and weaknesses - will be commented on. There are also some medicaments and instructions in dentistry that have no researched basis; some of these will also be identified and discussed.


Subject(s)
Postoperative Care/methods , Preoperative Care/methods , Root Canal Therapy/methods , Antibiotic Prophylaxis/methods , Humans , Root Canal Therapy/adverse effects , Surgical Wound Infection/prevention & control
4.
Br Dent J ; 218(5): 273-8, 2015 Mar 13.
Article in English | MEDLINE | ID: mdl-25766163

ABSTRACT

This article provides readers with an overview of available evidence in relation to providing care to patients in different medical circumstances within oral surgery. There is evidence available to support discussions with patients taking particular medications (such as bisphosphonates, anticoagulants and corticosteroids) and also to try to prevent certain complications (such as 'dry socket'). In order to reduce the risks of potential morbidities, either perioperatively or postoperatively, operators must use high-quality, reliable and informed protocols, management techniques, advice and interventions to provide patients with the best care. These are used both preoperatively and postoperatively and patients should be consented appropriately, in a manner tailored to their own individual circumstances, but also using available evidence to explain the benefits and harms of any given procedure. In this short series we will outline and discuss common pre- and postoperative management techniques, protocols and instructions, and the evidence available to support these.


Subject(s)
Oral Surgical Procedures/methods , Postoperative Care/methods , Preoperative Care/methods , Dry Socket/prevention & control , Humans , Oral Surgical Procedures/adverse effects , Postoperative Complications/prevention & control , Postoperative Hemorrhage/prevention & control , Risk Factors
5.
Br Dent J ; 218(5): 279-84, 2015 Mar 13.
Article in English | MEDLINE | ID: mdl-25766164

ABSTRACT

This article aims to highlight the strengths and weaknesses within the selected evidence to aid readers in clinical decision-making when managing patients before and after third molar surgery. Preoperative methods to prevent nerve damage, including the use of computed tomography (CT), are discussed. Preoperative considerations are also summarised, including risk factors such as increasing the occurrence of nerve deficit, weakness and damage, and the role of cone beam CT and when this should be used. The postoperative complications pain, swelling and infection are considered and the available evidence for the use of different protocols, regimes and combinations of therapies summarised.


Subject(s)
Molar, Third/surgery , Postoperative Care/methods , Preoperative Care/methods , Tooth Extraction/methods , Humans , Molar, Third/diagnostic imaging , Postoperative Complications/prevention & control , Radiography, Dental , Risk Factors , Tomography, X-Ray Computed , Tooth Extraction/adverse effects , Tooth, Impacted/surgery
6.
PLoS One ; 9(4): e95331, 2014.
Article in English | MEDLINE | ID: mdl-24748102

ABSTRACT

BACKGROUND: An important challenge to pulmonary arterial hypertension (PAH) diagnosis and treatment is early detection of occult pulmonary vascular pathology. Symptoms are frequently confused with other disease entities that lead to inappropriate interventions and allow for progression to advanced states of disease. There is a significant need to develop new markers for early disease detection and management of PAH. METHODOLGY AND FINDINGS: Exhaled breath condensate (EBC) samples were compared from 30 age-matched normal healthy individuals and 27 New York Heart Association functional class III and IV idiopathic pulmonary arterial hypertenion (IPAH) patients, a subgroup of PAH. Volatile organic compounds (VOC) in EBC samples were analyzed using gas chromatography/mass spectrometry (GC/MS). Individual peaks in GC profiles were identified in both groups and correlated with pulmonary hemodynamic and clinical endpoints in the IPAH group. Additionally, GC/MS data were analyzed using autoregression followed by partial least squares regression (AR/PLSR) analysis to discriminate between the IPAH and control groups. After correcting for medicaitons, there were 62 unique compounds in the control group, 32 unique compounds in the IPAH group, and 14 in-common compounds between groups. Peak-by-peak analysis of GC profiles of IPAH group EBC samples identified 6 compounds significantly correlated with pulmonary hemodynamic variables important in IPAH diagnosis. AR/PLSR analysis of GC/MS data resulted in a distinct and identifiable metabolic signature for IPAH patients. CONCLUSIONS: These findings indicate the utility of EBC VOC analysis to discriminate between severe IPAH and a healthy population; additionally, we identified potential novel biomarkers that correlated with IPAH pulmonary hemodynamic variables that may be important in screening for less severe forms IPAH.


Subject(s)
Breath Tests , Hypertension, Pulmonary/metabolism , Volatile Organic Compounds/analysis , Gas Chromatography-Mass Spectrometry , Humans , Least-Squares Analysis
7.
Br Dent J ; 215(5): 209-12, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24029981

ABSTRACT

This article provides an opinion on the NHS NICE guidance on wisdom tooth removal introduced in 2000. Guidelines should support clinical decision-making by providing recommendations based on sound evidence but the wisdom tooth guidelines were published without any research evidence. General dentists and oral surgeons in England and Wales are under pressure to comply with this guidance but what have been the implications for patient care? There is growing evidence that patients have not been best served, with significant numbers developing caries in an adjacent tooth before consideration of wisdom tooth assessment.


Subject(s)
Molar, Third/surgery , Practice Guidelines as Topic , Tooth Extraction/standards , Evidence-Based Dentistry/standards , Humans , State Medicine/standards , Tooth Extraction/adverse effects , United Kingdom
8.
IEEE Trans Nanobioscience ; 8(1): 92-9, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19307166

ABSTRACT

In this paper, we have proposed a fuzzy rule-based classifier for assigning amino acid sequences into different superfamilies of proteins. While the most popular methods for protein classification rely on sequence alignment, our approach is alignment-free and so more human readable. It accounts for the distribution of contiguous patterns of n amino acids ( n-grams) in the sequences as features, alike other alignment-independent methods. Our approach, first extracts a plenty of features from a set of training sequences, then selects only some best of them, using a proposed feature ranking method. Thereafter, using these features, a novel steady-state genetic algorithm for extracting fuzzy classification rules from data is used to generate a compact set of interpretable fuzzy rules. The generated rules are simple and human understandable. So, the biologists can utilize them, for classification purposes, or incorporate their expertise to interpret or even modify them. To evaluate the performance of our fuzzy rule-based classifier, we have compared it with the conventional nonfuzzy C4.5 algorithm, beside some other fuzzy classifiers. This comparative study is conducted through classifying the protein sequences of five superfamily classes, downloaded from a public domain database. The obtained results show that the generated fuzzy rules are more interpretable, with acceptable improvement in the classification accuracy.


Subject(s)
Algorithms , Fuzzy Logic , Pattern Recognition, Automated/methods , Proteins/chemistry , Sequence Alignment/methods , Sequence Analysis, Protein/methods , Amino Acid Sequence , Molecular Sequence Data , Sequence Homology, Amino Acid
9.
Br J Sports Med ; 42(4): 308-9; discussion 309, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17717059

ABSTRACT

Low back pain is a common complaint among cyclists. Here we present the case of a competitive master cyclist with low back pain and whose symptoms ultimately resolved when he was treated for internal snapping hip syndrome. Internal snapping hip syndrome is a painful lesion of the iliopsoas caused by snapping of the tendon over the iliopectineal eminence or anterior femoral head when the femur is extended from a flexed position. This is the first published report that we are aware of that describes this syndrome as a potential cause of low back pain in a competitive cyclist.


Subject(s)
Bicycling/physiology , Hip Joint/physiopathology , Low Back Pain/etiology , Physical Therapy Modalities , Tendons/physiopathology , Humans , Low Back Pain/therapy , Male , Middle Aged , Recovery of Function/physiology , Syndrome , Treatment Outcome
10.
Med Sci Sports Exerc ; 33(9): 1449-55, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11528331

ABSTRACT

PURPOSE: The purpose of this study was to examine the role of airway receptors in respiratory-related sensations after ascent to altitude. METHODS: Ratings of respiratory-related sensations, perceived exertion and acute mountain sickness, heart rate, and peripheral oxygen saturation were recorded at rest and exercise in male and female subjects who had inhaled either aerosolized saline or saline with tetracaine after acute ascent to an altitude of 3500 m and after prolonged acclimatization of 18 d at altitudes between 4000 and 5000 m. RESULTS: Tetracaine had no effect on respiratory-related sensations at altitude either at rest or during exercise, and male and female subjects experienced similar respiratory-related sensations. Sensations of rapid breathing were experienced at rest after acute exposure to 3500 m as compared with sea level, but not after acclimatization to 5000 m. Sensations of rapid breathing, air hunger, and heavy breathing were experienced during exercise after acute and prolonged altitude exposure as compared with sea level, with a sensation of chest tightness experienced at 3500 m and a sensation of gasping experienced at 5000 m. CONCLUSION: These results suggest that airway afferents play no role in the respiratory-related sensations experienced by male and female subjects either during acute ascent to altitude or after prolonged acclimatization at altitude.


Subject(s)
Altitude Sickness/physiopathology , Dyspnea/physiopathology , Respiratory Physiological Phenomena , Respiratory System/innervation , Adult , Dyspnea/etiology , Female , Heart Rate , Humans , Male , Oxygen/blood , Perception , Sex Factors , Tetracaine/pharmacology
11.
Respir Physiol ; 126(1): 9-27, 2001 May.
Article in English | MEDLINE | ID: mdl-11311307

ABSTRACT

Bleomycin treatment in rats results in pulmonary fibrosis that is characterized by a rapid shallow breathing pattern, a decrease in quasi-static lung compliance and a blunting of the Hering-Breuer Inflation Reflex. We examined the impulse activity of pulmonary vagal afferents in anesthetized, mechanically ventilated rats with bleomycin-induced lung fibrosis during the ventilator cycle and static lung inflations/deflations and following the injection of capsaicin into the right atrium. Bleomycin enhanced volume sensitivity of slowly adapting stretch receptors (SARs), while it blunted the sensitivity of these receptors to increasing transpulmonary pressure. Bleomycin treatment increased the inspiratory activity, while it decreased the expiratory activity of rapidly adapting stretch receptors (RARs). Pulmonary C-fiber impulse activity did not appear to be affected by bleomycin treatment. We conclude that the fibrosis-related shift in discharge profile and enhanced volume sensitivity of SARs combined with the increased inspiratory activity of RARs contributes to the observed rapid shallow breathing of bleomycin-induced lung fibrosis.


Subject(s)
Bleomycin , Lung/innervation , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/physiopathology , Vagus Nerve/physiopathology , Adaptation, Physiological , Afferent Pathways/physiopathology , Animals , Lung/physiopathology , Male , Nerve Fibers/physiology , Pulmonary Stretch Receptors/physiopathology , Rats , Rats, Wistar , Reference Values , Reflex , Respiration , Respiration, Artificial , Respiratory Function Tests , Time Factors
12.
Am J Occup Ther ; 55(2): 200-5, 2001.
Article in English | MEDLINE | ID: mdl-11761136

ABSTRACT

OBJECTIVE: This study examined retrospective data from a multidisciplinary work-hardening program that compared patients who did and did not return to work after low-back injury. The objective of this study was to identify differences between these groups to better guide work-hardening programs and return-to-work decisions. METHOD: Retrospective data from patients with low-back injuries (n = 115) who participated in a northern California work-hardening program were analyzed. Using two-way analysis of variance, male and female patients who did and did not return to work were compared. RESULTS: No significant differences were found between men and women for any of the variables studied. Patients who did and did not return to work were not significantly different in age, length of injury, and subjective pain at the beginning or end of the work-hardening program or in activity tolerance (p = .08). Patients who returned to work perceived a significantly (p < or = . 05) greater improvement in pain tolerance by the end of the work-hardening program than those who did not return to work. CONCLUSION: The results of this study suggest that rehabilitation emphasis should not be placed on the reduction of subjective pain but, rather, on strategies to cope with existing pain while improving functional ability.


Subject(s)
Employment/statistics & numerical data , Low Back Pain/classification , Low Back Pain/rehabilitation , Occupational Diseases/rehabilitation , Pain Threshold , Rehabilitation, Vocational/methods , Work Schedule Tolerance/physiology , Adult , Analysis of Variance , Female , Humans , Lumbar Vertebrae/injuries , Male , Pain Measurement , Probability , Registries , Retrospective Studies , Severity of Illness Index
13.
Mov Disord ; 15(2): 321-3, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10752585

ABSTRACT

Diagnostic criteria for restless legs syndrome (RLS) have been established; however, the pathophysiology of this common condition remains elusive. Several secondary forms of RLS potentially include renal failure, iron deficiency, pregnancy, and neuropathy. RLS has also been reported in approximately 25% of patients diagnosed with rheumatoid arthritis and Sjögren's syndrome. We performed clinical and serologic evaluations on 68 patients diagnosed with RLS to determine how many may have concurrent rheumatologic disease that could be causing their RLS symptoms. We compared these with other postulated secondary causes of RLS. No patient had clinical evidence of rheumatologic disease, and only four had any positive serologic evaluations (two positive SSA/SSB and two mildly elevated RF titers). Three of these had a positive family history for RLS. Patients without a family history of RLS did have lower ferritin levels, more cases of neuropathy, and an older age at symptom onset. We do not think rheumatologic disease represents a significant secondary cause of RLS and do not recommend serologic investigation unless there are overt clinical signs. In contrast, our study suggests that neuropathy and serum iron deficiency do represent secondary forms of RLS.


Subject(s)
Restless Legs Syndrome/etiology , Rheumatic Diseases/diagnosis , Adult , Aged , Antibodies, Antinuclear/blood , Arthritis, Rheumatoid/diagnosis , Female , Ferritins/blood , Humans , Male , Middle Aged , Restless Legs Syndrome/diagnosis , Restless Legs Syndrome/genetics , Rheumatoid Factor/blood , Risk Factors , Sjogren's Syndrome/diagnosis
14.
Lung ; 178(1): 41-52, 2000.
Article in English | MEDLINE | ID: mdl-10723719

ABSTRACT

In seven alpha-chloralose anesthetized dogs we examined the contribution of lung afferents to the rapid, shallow breathing induced by inhalation of 10 breaths of histamine aerosol. In four spontaneously breathing dogs, the inhalation of histamine caused an increased respiratory frequency, decreased tidal volume, and decreased dynamic lung compliance. Selective blockade of pulmonary C-fibers abolished a reflex-induced increase in respiratory frequency but did not significantly affect the reductions in tidal volume or lung compliance. Terbutaline treatment in combination with C-fiber blockade abolished the reductions in tidal volume and lung compliance induced by histamine. In three separate alpha-chloralose anesthetized, open-chest, mechanically ventilated dogs, we recorded an increase in the inspiratory activity of rapidly adapting pulmonary stretch receptors (RARs) induced by the inhalation of histamine aerosol. Selective C-fiber blockade abolished histamine-induced increases in RAR activity while only partially attenuating reductions in lung compliance. We conclude that the increase in RAR activity induced by histamine depends on intact C-fibers and not on a direct effect of histamine on RARs or an indirect effect of histamine reducing lung compliance. In addition, our data illustrate the multiple interactions that occur between the various vagal afferents and their roles in the reflexes induced by histamine inhalation.


Subject(s)
Histamine/pharmacology , Lung Compliance/drug effects , Lung/innervation , Pulmonary Ventilation/drug effects , Tidal Volume/drug effects , Vagus Nerve/drug effects , Administration, Inhalation , Afferent Pathways/drug effects , Afferent Pathways/physiopathology , Animals , Bronchial Hyperreactivity/physiopathology , Bronchial Provocation Tests , Dogs , Lung Compliance/physiology , Nerve Fibers/drug effects , Nerve Fibers/physiology , Pulmonary Stretch Receptors/drug effects , Pulmonary Stretch Receptors/physiology , Pulmonary Ventilation/physiology , Tidal Volume/physiology , Vagus Nerve/physiopathology
15.
Res Commun Mol Pathol Pharmacol ; 103(3): 260-8, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10509737

ABSTRACT

Pirfenidone is an antifibrotic drug that we have shown attenuates the increase in collagen buildup in hamsters exposed to bleomycin, in turn reducing pulmonary function and blood gas decrements seen in this model of interstitial pulmonary fibrosis. The systemic effects of pirfenidone ingestion, however, are unknown. We examined the effect of diet-ingested pirfenidone on pulmonary function, systemic and pulmonary cardiovasculature and blood gas measurements, breathing pattern and lung hydroxyproline content in rats fed either a control diet or a diet containing 0.5% pirfenidone. Residual volume was higher and expiratory reserve volume lower in the pirfenidone group, with no change in functional residual capacity. Tidal volume was also lower in the pirfenidone group, with no change in the overall level of ventilation. There was a trend toward a reduced hydroxyproline content and an increased lung compliance in the pirfenidone group. There were no differences in systemic or pulmonary pressures, cardiac output, stroke volume, heart rate, pH or blood gases between the two groups. These data indicate that pirfenidone has few systemic side-effects but may have a mild effect on the basal level of lung collagen content with resulting clinical changes in some pulmonary function measurements and changes in breathing pattern.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Cardiovascular System/drug effects , Lung/drug effects , Pyridones/pharmacology , Animals , Blood Gas Analysis , Blood Pressure/drug effects , Cardiac Output/drug effects , Expiratory Reserve Volume/drug effects , Heart Rate/drug effects , Hydroxyproline/metabolism , Lung/blood supply , Lung/metabolism , Lung/physiology , Male , Pulmonary Gas Exchange/drug effects , Rats , Rats, Wistar , Residual Volume/drug effects , Respiration/drug effects
16.
Proc Soc Exp Biol Med ; 216(3): 392-7, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9402144

ABSTRACT

The antifibrotic potential of pirfenidone (5-methyl-1-phenyl-2-[1H]-pyridone) was examined in a single intratracheal bleomycin dose hamster model of pulmonary fibrosis. Bleomycin-induced fibrosis and the effectiveness of pirfenidone treatment were assessed by measuring pulmonary functions (Cqst, TLC, VC, IC, FRC, RV) and the level of hydroxyproline in whole lung homogenates. Thirty-five male golden Syrian hamsters were randomized into four experimental groups: saline instilled and fed a control diet of rat chow (SCD, n = 8); saline instilled and fed the control diet containing 0.5% (w/w) pirfenidone (SPD, n = 8); bleomycin instilled and fed the control diet (BCD, n = 7); and bleomycin instilled and fed the control diet containing 0.5% pirfenidone (BPD, n = 10). Twenty-one days following bleomycin instillation Cqst/TLC, TLC, VC, and IC were significantly reduced and total lung hydroxyproline levels were significantly increased in the BCD and BPD groups as compared with the SCD and SPD groups, respectively. Pirfenidone ingestion significantly attenuated these bleomycin-induced pertubations in pulmonary functions and lung hydroxyproline levels (BCD versus BPD). The data obtained in this study provide evidence of the benefical effects of pirfenidone in the hamster model of bleomycin-induced pulmonary fibrosis both at the functional and biochemical level.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Bleomycin , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/physiopathology , Pyridones/therapeutic use , Animals , Body Weight/drug effects , Cardiovascular System/drug effects , Cricetinae , Hydroxyproline/metabolism , Lung/chemistry , Lung/drug effects , Male , Pulmonary Fibrosis/drug therapy , Respiration/drug effects , Respiratory Function Tests
17.
Exp Lung Res ; 23(5): 441-57, 1997.
Article in English | MEDLINE | ID: mdl-9267798

ABSTRACT

The role of nonmyelinated and myelinated vagal afferents in pulmonary reflexes and breathing pattern was examined in elastase-treated emphysemic rats. Fourteen to 17 days after intratracheal instillation of 1 IU/gm of porcine pancreatic elastase or 0.5 mL of saline, elastase-treated rats had a decreased alveolar surface area to volume of parenchyma (Sv) (42.44 +/- 1.7 vs. 31.51 +/- 1.1 mm2/mm3), increased quasistatic compliance (QSC) (1.05 +/- 0.06 vs. 1.25 +/- 0.09 mL/cm H2O), functional residual capacity (FRC) (4.31 +/- 0.10 vs. 5.88 +/- 0.37 mL), residual volume (RV) (3.02 +/- 0.14 vs. 4.27 +/- 0.31 mL), and total lung capacity (TLC) (14.04 +/- 0.28 vs. 15.58 +/- 0.54 mL). There were no changes in the strength of the pulmonary chemoreflex, the strength of the Hering-Breuer inflation reflex, or breathing pattern before or after vagal perineural capsaicin treatment (VPCT) or vagotomy. There were, however, significant negative correlations between Sv and TLC, FRC and RV, and a near significant (p < .09) negative correlation between Sv and QSC, but no significant correlations between Sv and indices of either the pulmonary chemoreflex or Hering-Breuer inflation reflex. The results indicate that pulmonary vagal nonmyelinated and myelinated reflex activity and breathing pattern are not affected by elastase-induced emphysema in rats.


Subject(s)
Emphysema/chemically induced , Emphysema/physiopathology , Pancreatic Elastase/toxicity , Respiration/physiology , Vagus Nerve/physiopathology , Animals , Carbon Dioxide/blood , Disease Models, Animal , Emphysema/pathology , Hydrogen-Ion Concentration , Lung/drug effects , Lung/physiopathology , Male , Neurons, Afferent/drug effects , Neurons, Afferent/physiology , Oxygen/blood , Rats , Rats, Wistar , Reflex/drug effects , Reflex/physiology , Vagotomy
18.
Respir Physiol ; 108(1): 45-61, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9178376

ABSTRACT

In anesthestized male Wistar rats with bleomycin-induced lung fibrosis we examined the influence of lung vagal non-myelinated and myelinated afferents in setting breathing pattern. Fourteen days after intratracheal instillation of bleomycin, lung compliance, total lung capacity (TLC) and inspiratory capacity were reduced while functional residual capacity and residual volume were increased. Baseline tidal volume (VT) was decreased and frequency (fR) increased in the bleomycin treated rats compared with controls. Selective vagal C-fiber blockade did not affect fR or VT in any group. Vagotomy resulted in an increase in VT and decrease in fR in both groups with the percent increase in VT/TLC and decrease in fR being significantly greater in the bleomycin rats compared with controls. Vagotomy also attenuated the significantly elevated PCO2 in the bleomycin treated rats suggesting that bleomycin-induced alterations in breathing pattern contribute to blood gas abnormalities. We conclude that vagal myelinated afferents contribute to the rapid shallow breathing in bleomycin treated rats.


Subject(s)
Lung/physiopathology , Neurons, Afferent/physiology , Pulmonary Fibrosis/physiopathology , Respiration/physiology , Vagus Nerve/physiopathology , Animals , Bleomycin , Capsaicin/pharmacology , Carbon Dioxide/blood , Hydrogen-Ion Concentration , Lung/anatomy & histology , Lung/innervation , Male , Oxygen/blood , Partial Pressure , Pulmonary Fibrosis/chemically induced , Rats , Rats, Wistar , Respiratory Function Tests , Vagotomy , Vagus Nerve/drug effects , Vagus Nerve/surgery
19.
J Appl Physiol (1985) ; 79(2): 600-6, 1995 Aug.
Article in English | MEDLINE | ID: mdl-7592224

ABSTRACT

In 19 dogs anesthetized with xylazine and alpha-chloralose, we examined the influence of background vagal C-fiber activity on the breathing pattern using a modified perineural capsaicin treatment. In seven dogs, we tested the efficacy of this treatment by recording compound action potentials before and after capsaicin application. In the remaining 12 dogs, we examined the effect of vagal perineural capsaicin on the Hering-Breuer expiratory facilitatory inflation reflex, pulmonary chemoreflex, and breathing pattern (tidal volume and expiratory and inspiratory times). Neither the peak height nor integral of the A wave of the compound action potential was significantly affected. However, the peak height and integral of the C wave of the compound action potential were significantly affected. However, the peak height and integral of the C wave of the compound action potential were significantly reduced. The myelinated fiber-initiated Hering-Breuer reflex remained intact after perineural capsaicin, but the C-fiber-initiated pulmonary chemoreflex was abolished. Perineural capsaicin increased tidal volume (0.399 +/- 0.031 to 0.498 +/- 0.058 liter; P < 0.05), expiratory time (3.62 +/- 0.31 to 4.82 +/- 0.68 s; P < 0.05), inspiratory time (1.49 +/- 0.12 to 1.72 +/- 0.17 s; P < 0.10) and total time per breath (5.11 +/- 1.08 to 6.54 +/- 0.82 s; P < 0.05). We conclude that background vagal C-fiber activity exerts an inhibitory effect on tidal volume and an excitatory effect on breathing frequency.


Subject(s)
Nerve Fibers/physiology , Respiratory Mechanics/physiology , Vagus Nerve/physiology , Action Potentials/drug effects , Action Potentials/physiology , Anesthesia , Animals , Blood Gas Analysis , Capsaicin/pharmacology , Dogs , Hemodynamics/drug effects , Nerve Fibers/drug effects , Reflex/drug effects , Respiratory Mechanics/drug effects , Stimulation, Chemical , Vagus Nerve/cytology , Vagus Nerve/drug effects
SELECTION OF CITATIONS
SEARCH DETAIL