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1.
Eur Ann Otorhinolaryngol Head Neck Dis ; 138(4): 241-245, 2021 Sep.
Article in English | MEDLINE | ID: mdl-33309220

ABSTRACT

OBJECTIVES: Vocal morbidity resulting from damage to the motor branch of the superior laryngeal nerve (SLN) after endocrine surgery is well known, but diagnosis is often delayed. The present study aimed to quantify these vocal changes acoustically (main objective), and correlate this with the vocal complaints of patients with suspected SLN motor impairment (secondary objective). MATERIAL AND METHODS: Thirty females patients with suspected injury of the SLN cricothyroid branch (CT-) were compared to 30 patients without postoperative vocal impairment (CT+) and to 30 control subjects. Mean, minimal and maximal fundamental frequencies (F0mean, F0min and F0max) and vocal range were measured on /e/ at high frequency, sirens (glissandi), a reading text, and minimal intonation pairs. Subjective vocal impairment was evaluated on the Voice Handicap Index (VHI). RESULTS: A lowering of F0mean associated with vocal range reduction by one fifth (in the reading text) seemed to be specific to CT- patients. Production of questions was affected, with differences in melodic curve and attack. Thyroidectomy within 2 months in itself (without suspected SLN cricothyroid branch injury) also affected these parameters, but to a lesser degree. CT- patients reported greater voice impairment than CT+ patients or controls (P=0.0004). CONCLUSION: Alterations in speech intonation, quantified on minimal pair test, and self-assessed vocal handicap (VHI) are tools that can easily be used in daily practice to screen for SLN motor branch lesion.


Subject(s)
Voice Disorders , Voice , Female , Humans , Laryngeal Nerves , Self Concept , Thyroidectomy , Voice Disorders/etiology
2.
Viruses ; 11(6)2019 06 08.
Article in English | MEDLINE | ID: mdl-31181775

ABSTRACT

VP22 is a major tegument protein of alphaherpesviruses encoded by the UL49 gene. Two properties of VP22 were discovered by studying Marek's disease virus (MDV), the Mardivirus prototype; it has a major role in virus cell-to-cell spread and in cell cycle modulation. This 249 AA-long protein contains three regions including a conserved central domain. To decipher the functional VP22 domains and their relationships, we generated three series of recombinant MDV genomes harboring a modified UL49 gene and assessed their effect on virus spread. Mutated VP22 were also tested for their ability to arrest the cell cycle, subcellular location and histones copurification after overexpression in cells. We demonstrated that the N-terminus of VP22 associated with its central domain is essential for virus spread and cell cycle modulation. Strikingly, we demonstrated that AAs 174-190 of MDV VP22 containing the end of a putative extended alpha-3 helix are essential for both functions and that AAs 159-162 located in the putative beta-strand of the central domain are mandatory for cell cycle modulation. Despite being non-essential, the 59 C-terminal AAs play a role in virus spread efficiency. Interestingly, a positive correlation was observed between cell cycle modulation and VP22 histones association, but none with MDV spread.


Subject(s)
Cell Cycle Checkpoints/physiology , Cell Nucleus/metabolism , Herpesvirus 2, Gallid/isolation & purification , Histones/metabolism , Marek Disease/virology , Protein Domains , Viral Proteins/metabolism , Amino Acid Sequence , Animals , Cell Cycle , Chickens , DNA, Viral/analysis , DNA, Viral/genetics , Gene Expression Regulation, Viral , Herpesvirus 2, Gallid/genetics , Herpesvirus 2, Gallid/growth & development , Mardivirus/genetics , Mardivirus/isolation & purification , Sequence Analysis, Protein , Viral Proteins/genetics , Viral Structural Proteins , Virus Replication
3.
Orthopade ; 42(3): 164-9, 2013 Mar.
Article in German | MEDLINE | ID: mdl-23455315

ABSTRACT

BACKGROUND: The purpose of this present study was to review the functional and radiological results of patients with complex fractures of the proximal humerus who were treated with an anatomical shoulder prosthesis. PATIENTS AND METHODS: Between 1999 and 2005 a total of 61 patients were treated with an anatomical trauma prosthesis after an acute fracture. RESULTS: Thirty-eight patients (31 women and 7 men) with a mean age of 72 (range, 31-85) years could be followed-up. The absolute Constant score averaged 57.7 of 100 (range, 32-86) points by a mean of 86 (range, 60-129) months. Postoperative active elevation averaged 105 (range, 50-180)° and active abduction averaged 96 (50-180)°. Tuberosity resorption was found in 52% (20/38) at final follow-up. The outcome was significantly better in patients with healing of the tuberosities (p = 0.02). CONCLUSION: With the use of an anatomical trauma prosthesis the reduction of the pain level is excellent while the gain in function is only slight. The bony union of the tuberosities in an anatomical position is essential to achieve good results.


Subject(s)
Joint Prosthesis , Shoulder Fractures/surgery , Shoulder Injuries , Shoulder Joint/surgery , Adult , Aged , Aged, 80 and over , Equipment Failure Analysis , Female , Humans , Male , Middle Aged , Prosthesis Design , Radiography , Shoulder Fractures/diagnostic imaging , Shoulder Joint/diagnostic imaging , Treatment Outcome
4.
Orthop Traumatol Surg Res ; 98(6): 659-65, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22944393

ABSTRACT

BACKGROUND: The indications for hemiarthroplasty in glenohumeral joint diseases remain controversial and depend mainly on the original underlying diagnosis. Our objective was to investigate the influence of the primitive aetiology on long-term prosthesis survival and on the Constant-Murley score. MATERIALS AND METHODS: We studied 272 shoulders with the following diagnoses: fracture sequelae (n=73), primary osteoarthritis (n=67), cuff tear arthropathy (n=43), avascular necrosis (n=40), rheumatoid arthritis (n=31), and other (n=18). Of the 272 shoulders, 139 were evaluated after at least 8 years (mean follow-up, 134 months). In all, 30 prostheses required removal. Functional status was evaluated using the Constant-Murley score and survival rate using the Kaplan-Meier method with prosthesis removal or conversion to total arthroplasty as the endpoint. RESULTS: Ten-year prosthesis survival was 88.13% overall, 100% in the rheumatoid arthritis group, 94.9% in the avascular necrosis group, 94.2% in the primary osteoarthritis group, 81.5% in the cuff tear arthropathy group, and 76.8% in the fracture sequelae (P=0.05). The mean Constant-Murley score after 8 years or more was 70.1 in avascular necrosis, 60.7 in primary osteoarthritis, 57.7 in fracture sequelae, 55.3 in rheumatoid arthritis, and 46.2 in cuff tear arthropathy (P=0.0006). The complication rate with the initial population as the denominator was 24.7% in fracture sequelae, 18.6% in cuff tear arthropathy, 15% in avascular necrosis, 8.9% in primary osteoarthritis, and 3.2% in rheumatoid arthritis. CONCLUSIONS: The best indication for shoulder hemiarthroplasty is avascular necrosis and the worst indications are cuff tear and post-traumatic fracture sequellae. Rheumatoid arthritis and primary glenohumeral osteoarthritis are good indications in patients younger than 50 years of age. LEVEL OF EVIDENCE: Level IV, retrospective study.


Subject(s)
Joint Prosthesis , Osteoarthritis/surgery , Shoulder Joint/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Middle Aged , Osteoarthritis/physiopathology , Prosthesis Failure , Range of Motion, Articular , Retrospective Studies , Shoulder Joint/physiopathology , Time Factors , Treatment Outcome , Young Adult
5.
J Bone Joint Surg Br ; 92(10): 1403-9, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20884979

ABSTRACT

Fractures of the proximal humerus can lead to malalignment of the humeral head, necrosis and post-traumatic osteoarthritis. In such cases surface replacement might be a promising option. A total of 28 shoulders with glenohumeral arthritis subsequent to a fracture underwent surface replacement arthroplasty of the humeral head in patients with a mean age of 60 years (35 to 83). On the basis of the inclination of the impacted head, post-traumatic arthritis was divided into three types: type 1, an impacted fracture of the head in an anatomical position (seven cases); type 2, a valgus impacted fracture (13 cases); type 3, a varus impacted fracture (eight cases). The outcome was measured by means of the Constant score. According to the Boileau classification of the sequelae of fractures of the proximal humerus, all 28 patients had a final result of intra-capsular category 1. The mean Constant score for the 28 shoulders increased from 23.2 points (2 to 45) pre-operatively to 55.1 points (20 to 89) at a mean of 31 months (24 to 66) post-operatively. Valgus impacted fractures had significantly better results (p < 0.039). Surface replacement arthroplasty can provide good results for patients with post-traumatic osteoarthritis of the shoulder. Their use avoids post-operative complications of the humeral shaft, such as peri-prosthetic fractures. Further surgery can be undertaken more easily as the bone stock is preserved.


Subject(s)
Arthroplasty, Replacement/methods , Humerus/surgery , Osteoarthritis/etiology , Osteoarthritis/surgery , Shoulder Fractures/complications , Adult , Aged , Aged, 80 and over , Arthroplasty, Replacement/adverse effects , Female , Follow-Up Studies , Humans , Male , Middle Aged , Osteoarthritis/diagnostic imaging , Osteoarthritis/physiopathology , Patient Satisfaction , Radiography , Range of Motion, Articular , Recovery of Function , Shoulder Fractures/diagnostic imaging , Shoulder Fractures/physiopathology , Shoulder Joint/diagnostic imaging , Shoulder Joint/physiopathology , Shoulder Joint/surgery , Treatment Outcome
6.
Z Orthop Unfall ; 148(6): 680-4, 2010 Dec.
Article in German | MEDLINE | ID: mdl-20563970

ABSTRACT

AIM: Loosening of the glenoid component is one of the major causes of failure in total shoulder arthroplasty. Possible risk factors for loosening of cemented components include an eccentric loading, poor bone quality, inadequate cementing technique and insufficient cement penetration. The application of a modern cementing technique has become an established procedure in total hip arthroplasty. The goal of modern cementing techniques in general is to improve the cement-penetration into the cancellous bone. Modern cementing techniques include the cement vacuum-mixing technique, retrograde filling of the cement under pressurisation and the use of a pulsatile lavage system. The main purpose of this study was to analyse cement penetration into the glenoid bone by using modern cement techniques and to investigate the relationship between the bone mineral density (BMD) and the cement penetration. Furthermore we measured the temperature at the glenoid surface before and after jet-lavage of different patients during total shoulder arthroplasty. It is known that the surrounding temperature of the bone has an effect on the polymerisation of the cement. Data from this experiment provide the temperature setting for the in-vitro study. METHOD: The glenoid surface temperature was measured in 10 patients with a hand-held non-contact temperature measurement device. The bone mineral density was measured by DEXA. Eight paired cadaver scapulae were allocated (n = 16). Each pair comprised two scapulae from one donor (matched-pair design). Two different glenoid components were used, one with pegs and the other with a keel. The glenoids for the in-vitro study were prepared with the bone compaction technique by the same surgeon in all cases. Pulsatile lavage was used to clean the glenoid of blood and bone fragments. Low viscosity bone cement was applied retrogradely into the glenoid by using a syringe. A constant pressure was applied with a modified force sensor impactor. Micro-computed tomography scans were applied to analyse the cement penetration into the cancellous bone. RESULTS: The mean temperature during the in-vivo arthroplasty of the glenoid was 29.4 °C (27.2-31 °C) before and 26.2 °C (25-27.5 °C) after jet-lavage. The overall peak BMD was 0.59 (range 0.33-0.99) g/cm (2). Mean cement penetration was 107.9 (range 67.6-142.3) mm (2) in the peg group and 128.3 (range 102.6-170.8) mm (2) in the keel group. The thickness of the cement layer varied from 0 to 2.1 mm in the pegged group and from 0 to 2.4 mm in the keeled group. A strong negative correlation between BMD and mean cement penetration was found for the peg group (r (2) = -0.834; p < 0.01) and for the keel group (r (2) = -0.727; p < 0.041). Micro-CT shows an inhomogenous dispersion of the cement into the cancellous bone. CONCLUSIONS: Data from the in-vivo temperature measurement indicate that the temperature at the glenohumeral surface under operation differs from the body core temperature and should be considered in further in-vitro studies with human specimens. Bone mineral density is negatively correlated to cement penetration in the glenoid. The application of a modern cementing technique in the glenoid provides sufficient cementing penetration although there is an inhomogenous dispersion of the cement. The findings of this study should be considered in further discussions about cementing technique and cement penetration into the cancellous bone of the glenoid.


Subject(s)
Arthroplasty, Replacement/methods , Cementation/methods , Joint Prosthesis , Shoulder Joint/physiopathology , Shoulder Joint/surgery , Adhesiveness , Adult , Aged , Body Temperature , Female , Humans , Male , Middle Aged , Treatment Outcome , Young Adult
7.
J Bone Joint Surg Br ; 92(3): 387-92, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20190310

ABSTRACT

We have investigated the mid-term outcome of total shoulder replacement using a keeled cemented glenoid component and a modern cementing technique with regard to the causes of failure and loosening of the components. Between 1997 and 2003 we performed 96 total shoulder replacements on 88 patients, 24 men and 64 women with a mean age of 69.7 years (31 to 82). The minimum follow-up was five years and at the time of review 87 shoulders (77 patients) were examined at a mean follow-up of 89.1 months (60 to 127). Cumulative survival curves were generated with re-operations (accomplished and planned), survivorship of the proshesis, loosening of the glenoid (defined as tilt > 5 degrees or subsidence > 5 mm), the presence of radiolucent lines and a Constant score of < 30 as the endpoints. There were two re-operations not involving revision of the implants and the survival rate of the prosthesis was 100.0% for the follow-up period, with an absolute Constant score of > 30 as the endpoint the survival rate was 98%. Radiological glenoid loosening was 9% after five years, and 33% after nine years. There was an incidence of 8% of radiolucent lines in more than three of six zones in the immediate post-operative period, of 37.0% after the first year which increased to 87.0% after nine years. There was no correlation between the score of Boileau and the total Constant score at the latest follow-up, but there was correlation between glenoid loosening and pain (p = 0.001). We found that total shoulder replacement had an excellent mid-term survivorship and clinical outcome. The surgical and cementing techniques were related to the decrease in radiolucent lines around the glenoid compared with earlier studies. One concern, however, was the fact that radiolucent lines increased over time and there was a rate of glenoid loosening of 9% after five years and 33% after nine years. This suggests that the design of the glenoid component, and the implantation and cementing techniques may need further improvement.


Subject(s)
Arthroplasty, Replacement/methods , Cementation/methods , Shoulder Joint/surgery , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Middle Aged , Osteoarthritis/surgery , Postoperative Complications , Prosthesis Design , Prosthesis Failure , Radiography , Reoperation , Shoulder Joint/diagnostic imaging , Survival Analysis , Treatment Outcome
8.
Z Orthop Unfall ; 148(6): 674-9, 2010 Dec.
Article in German | MEDLINE | ID: mdl-20135592

ABSTRACT

AIM: The purpose of this clinical study (matched-pair design) was to compare the functional short-term results obtained in patients with surface replacement of the humeral head and cemented glenoid prosthesis with those obtained after total shoulder arthroplasty. METHOD: 20 patients (average age 67.7 [43-85] years, 17 women, three men) who received surface replacement of the humeral head with cemented glenoid prosthesis were matched to a control group of 20 patients (average age 67.55 [42-85] years, 17 women, three men) with a conventional total shoulder arthroplasty. Six patients were treated for osteoarthritis, two for post-traumatic arthritis, 1 each for osteonecrosis and rheumatoid arthritis. Preoperative status, perioperative results and postoperative status (Constant score, subjective assessment, range of motion, radiographic evaluation) were compared in all patients and controls. RESULTS: The adjusted Constant score improved from a mean of 37.25% to a mean of 87.75% in the hybrid group and from a mean of 30.8% to a value of 87.1% in the TSA group. Regarding the relative improvement at 12 months compared to baseline, patients treated with hybrid prostheses showed a comparable benefit in the Constant score, pain reduction and range of motion. Only the criterion "strength" revealed a significantly better result in the TSA group (p = 0.025). There was one irreversible injury of the brachial plexus in one case and neural injuries with a full recovery in two cases of Hybrid prosthesis. CONCLUSIONS: The combination of humeral surface replacement with cemented glenoid component offers a relatively new option for the treatment of different pathologies at the shoulder joint which need a total joint substitute.The short-term results are comparable with those of conventional total shoulder arthroplasty. Surface replacement of the shoulder facilitates later revision because of less loss of bone stock. It must be considered that surface replacement with implantation of cemented glenoid prosthesis is a difficult procedure because of the exploration of the glenoid.


Subject(s)
Arthroplasty, Replacement/methods , Cementation/methods , Joint Prosthesis , Shoulder Joint/surgery , Adult , Aged , Aged, 80 and over , Case-Control Studies , Female , Humans , Male , Middle Aged , Treatment Outcome
9.
Orthopade ; 39(2): 201-8, 2010 Feb.
Article in German | MEDLINE | ID: mdl-19768450

ABSTRACT

BACKGROUND: Cementless humeral surface replacement arthroplasty is a viable treatment option for degenerative diseases of the shoulder joint. The aim of this prospective study was to analyse the results of this treatment option in patients younger than 55 years of age with different pathologies of the shoulder. PATIENTS AND METHODS: Twenty-three patients (26 implants) treated with cementless humeral surface replacement arthroplasty were included in this study. Mean follow-up was 2.5 years (1-6 years). Ten patients had posttraumatic osteoarthritis, seven had primary osteoarthritis, and six had osteonecrosis. Patients were evaluated using the Constant score, shoulder motion, and subjective satisfaction. RESULTS: The mean Constant score increased significantly from 33 points preoperatively (8-69 points) to 61 points postoperatively (25-83 points; p<0.0001), adjusted to age and gender from 38% (8-86%) to 70% (28-114%; p<0.0001). Significant improvement for the whole cohort was found regarding patients' pain, activity, mobility, shoulder flexion and abduction, and internal and external rotation (p<0.001). In one case, reoperation was necessary due to a superficial wound infection, and in another case, implant revision to a total shoulder replacement was performed because of glenoid erosion. CONCLUSION: Cementless humeral surface replacement arthroplasty is a viable bone-preserving treatment option for young and active patients. Later conversion to total shoulder replacement is possible. Good clinical results, a low complication rate, and high patient satisfaction were found in the short and mid term. Long-term investigations are necessary to confirm these observations.


Subject(s)
Arthroplasty, Replacement/methods , Joint Prosthesis , Osteoarthritis/surgery , Osteonecrosis/surgery , Shoulder Joint/surgery , Adult , Female , Follow-Up Studies , Humans , Male , Middle Aged , Osteoarthritis/diagnostic imaging , Osteonecrosis/diagnostic imaging , Postoperative Complications/diagnostic imaging , Postoperative Complications/surgery , Prosthesis Design , Radiography , Range of Motion, Articular/physiology , Reoperation , Shoulder Dislocation/diagnostic imaging , Shoulder Dislocation/surgery , Shoulder Joint/diagnostic imaging
10.
J Viral Hepat ; 13(10): 708-14, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16970603

ABSTRACT

Hepatitis C virus (HCV) readily sets up persistence after acute infection. Cellular immune responses are thought to play a major role in control of the virus. Failure of CD4+ T-cell responses in acute disease is associated with viral persistence but the dynamics of this are poorly understood. We aimed to assess such responses using a novel set of Class II tetrameric complexes (tetramers) to study helper T-cells ex vivo in acute disease. We analysed the HCV-specific CD4+ T-cell response in a patient with acute hepatitis c infection. We were able to track the virus-specific CD4+ T-cells directly ex vivo with HLA DR4 tetramers. Proliferative responses were absent initially, recovered as viral load dropped and were lost again during relapse. Longitudinal tetramer analyses showed expanded populations of antiviral CD4+ T-cells throughout acute infection despite lack of proliferation. A pattern of transient CD4+ T-cell proliferative responses as HCV is partially controlled is observed. Failure to control virus is associated with emergence of 'dysfunctional' CD4+ T-cell populations. Failure to control HCV in acute disease may relate to the capacity to sustain efficient immune responses as virus attempts to 'bounce back' after partial control.


Subject(s)
Hepatitis C/immunology , T-Lymphocytes, Helper-Inducer/immunology , Acute Disease , Antigens, Viral , Antiviral Agents/therapeutic use , HLA-DR Antigens/genetics , HLA-DRB1 Chains , Hepatitis C/drug therapy , Humans , Interferon-alpha/therapeutic use , Lymphocyte Activation , Ribavirin/therapeutic use , T-Lymphocyte Subsets/immunology
11.
J Virol ; 79(19): 12425-33, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16160170

ABSTRACT

The hepatitis C virus (HCV)-specific CD4+ T-cell response against nonstructural proteins is strongly associated with successful viral clearance during acute hepatitis C. To further develop these observations into peptide-based vaccines and clinical immunomonitoring tools like HLA class II tetramers, a detailed characterization of immunodominant CD4+ T-cell epitopes is required. We studied peripheral blood mononuclear cells from 20 patients with acute hepatitis C using 83 overlapping 20-mer peptides covering the NS3 helicase and NS4. Eight peptides were recognized by > or = 40% of patients, and specific CD4+ T-cell clones were obtained for seven of these and three additional, subdominant epitopes. Mapping of minimal stimulatory sequences defined epitopes of 8 to 13 amino acids in length, but optimal T-cell stimulation was observed with 10- to 15-mers. While some epitopes were presented by different HLA molecules, others were presented by only a single HLA class II molecule, which has implications for patient selection in clinical trials of peptide-based immunotherapies. In conclusion, using two different approaches we identified and characterized a set of CD4+ T-cell epitopes in the HCV NS3-NS4 region which are immunodominant in patients achieving transient or persistent viral control. This information allows the construction of a valuable panel of HCV-specific HLA class II tetramers for further study of CD4+ T-cell responses in chronic hepatitis C. The finding of immunodominant epitopes with very constrained HLA restriction has implications for patient selection in clinical trials of peptide-based immunotherapies.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Hepacivirus/immunology , Immunodominant Epitopes , Viral Nonstructural Proteins/immunology , Adolescent , Adult , Alleles , Amino Acid Sequence , Antigen Presentation , Female , HLA Antigens/genetics , HLA Antigens/physiology , Hepatitis C/immunology , Humans , Leukocytes, Mononuclear/immunology , Lymphocyte Activation , Male , Middle Aged , Molecular Sequence Data
12.
Behav Processes ; 67(2): 235-44, 2004 Sep 30.
Article in English | MEDLINE | ID: mdl-15497257

ABSTRACT

In order to assess the influence of environmental parameters on their behaviour, 16 European brown bears were observed in six different zoological parks. Activities were measured by scan sampling and their relationships to housing conditions were established by multifactorial correspondence analysis and cluster analysis. The largest enclosures were characterised by high scores of play, social behaviours, eating, and interest in the inside as well as the outside of the enclosure. Because these parks were newer, their bears were the youngest of those studied. Stereotypies were associated with medium age animals and small enclosures. The oldest subjects were characterised by high frequencies of resting. Stereotyped walk was observed only in those parks where keepers throw food to the bears. This result and detailed observation of stereotyped movements suggest that the meaning of the stereotypy for the animal could be to induce the keeper's arrival.


Subject(s)
Animals, Zoo , Behavior, Animal/physiology , Social Behavior , Stereotyped Behavior , Animals , Locomotion/physiology , Ursidae
14.
Behav Processes ; 58(1-2): 45-55, 2002 May 28.
Article in English | MEDLINE | ID: mdl-11955770

ABSTRACT

Increased physical exercise is known to prevent leg problems in meat-type chickens. Our aims were to study in detail the organisation of general and locomotor activity, to determine how physical exercise could be promoted and to investigate the effects of tonic immobility (TI) duration on spontaneous activity. Chicks were allocated to two groups according to their TI duration at 3 and 20 days (fearful birds, HF, n=11; non-fearful birds, LF, n=14). The behaviour patterns expressed by awake birds were recorded as 'activity bouts'. Activity bouts were then classified into five classes according to the most long-lasting activity in the bout. The behaviour patterns were similar in both groups. The FORAGING class contained long-lasting bouts with high levels of locomotor activity which decreased considerably with age, when bouts of EATING and DRINKING classes became more and more numerous. Bouts in the PREENING and NONE classes contained low activity. In conclusion, the level of activity in home pens was poorly related to TI. Categorisation of bouts into five classes is valuable to understand the general organisation of activity in chickens. The FORAGING class included bouts with high levels of locomotion and it could thus be used as a general indicator of activity.

16.
J Virol ; 75(17): 7803-10, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11483723

ABSTRACT

CD4(+) T cells play a major role in the host defense against viruses and intracellular microbes. During the natural course of such an infection, specific CD4(+) T cells are exposed to a wide range of antigen concentrations depending on the body compartment and the stage of disease. While epitope variants trigger only subsets of T-cell effector functions, the response of virus-specific CD4(+) T cells to various concentrations of the wild-type antigen has not been systematically studied. We stimulated hepatitis B virus core- and hepatitis C virus NS3-specific CD4(+) T-cell clones which had been isolated from patients with acute hepatitis during viral clearance with a wide range of specific antigen concentrations and determined the phenotypic changes and the induction of T-cell effector functions in relation to T-cell receptor internalization. A low antigen concentration induced the expression of T-cell activation markers and adhesion molecules in CD4(+) T-cell clones in the absence of cytokine secretion and proliferation. The expression of CD25, HLA-DR, CD69, and intercellular cell adhesion molecule 1 increased as soon as T-cell receptor internalization became detectable. A 30- to 100-fold-higher antigen concentration, corresponding to the internalization of 20 to 30% of T-cell receptor molecules, however, was required for the induction of proliferation as well as for gamma interferon and interleukin-4 secretion. These data indicate that virus-specific CD4(+) T cells can respond to specific antigen in a graded manner depending on the antigen concentration, which may have implications for a coordinate regulation of specific CD4(+) T-cell responses.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Hepacivirus/immunology , Hepatitis B virus/immunology , Receptors, Antigen, T-Cell/immunology , Receptors, Antigen, T-Cell/metabolism , Cell Adhesion Molecules/metabolism , Clone Cells , Hepatitis B/immunology , Hepatitis B/virology , Hepatitis B Core Antigens/immunology , Hepatitis C/immunology , Hepatitis C/virology , Humans , Immunologic Memory , Lymphocyte Activation/immunology , Receptors, Interleukin-2/metabolism , Viral Nonstructural Proteins/immunology
17.
J Virol ; 75(12): 5550-8, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11356962

ABSTRACT

Hepatitis C virus (HCV) sets up persistent infection in the majority of those exposed. It is likely that, as with other persistent viral infections, the efficacy of T-lymphocyte responses influences long-term outcome. However, little is known about the functional capacity of HCV-specific T-lymphocyte responses induced after acute infection. We investigated this by using major histocompatibility complex class I-peptide tetrameric complexes (tetramers), which allow direct detection of specific CD8+ T lymphocytes ex vivo, independently of function. Here we show that, early after infection, virus-specific CD8+ T lymphocytes detected with a panel of four such tetramers are abnormal in terms of their synthesis of antiviral cytokines and lytic activity. Furthermore, this phenotype is commonly maintained long term, since large sustained populations of HCV-specific CD8+ T lymphocytes were identified, which consistently had very poor antiviral cytokine responses as measured in vitro. Overall, HCV-specific CD8+ T lymphocytes show reduced synthesis of tumor necrosis factor alpha (TNF-alpha) and gamma interferon (IFN-gamma) after stimulation with either mitogens or peptides, compared to responses to Epstein-Barr virus and/or cytomegalovirus. This behavior of antiviral CD8+ T lymphocytes induced after HCV infection may contribute to viral persistence through failure to effectively suppress viral replication.


Subject(s)
CD8-Positive T-Lymphocytes/pathology , Cytokines/metabolism , Hepacivirus/immunology , Hepacivirus/pathogenicity , Hepatitis C/immunology , Acute Disease , Adult , Antigens, CD/metabolism , Antigens, Differentiation, T-Lymphocyte/metabolism , CD8-Positive T-Lymphocytes/immunology , Female , Hepatitis C/physiopathology , Humans , Interferon-gamma/biosynthesis , Lectins, C-Type , Lymphocyte Activation , Male , Receptors, Antigen, T-Cell, alpha-beta/metabolism
19.
J Infect Dis ; 183(8): 1187-94, 2001 Apr 15.
Article in English | MEDLINE | ID: mdl-11262200

ABSTRACT

The role of hepatitis C virus (HCV)-specific CD4+ T cells in recurrent HCV infection after orthotopic liver transplantation (OLTx) is unclear. In parallel, 73 intrahepatic and 73 blood-derived T cell lines were established from 34 patients. At a single cell level, virus-specific interferon (IFN)-gamma production to various HCV proteins was determined by ELISPOT assay: 45 (62%) of 73 liver- or blood-derived T cell lines produced IFN-gamma in response to one of the HCV antigens. HCV specificity was detected mainly in the liver (47% vs. 23% in the blood; P<.05, chi(2) test) and was detectable earlier (< or =6 months) significantly more often than later (>6 months) after OLTx (78% vs 49%; P<.05, chi(2) test). Histology, histologic activity index, liver enzymes, and virus load did not correlate with the occurrence of HCV-specific CD4+ T cells. Despite strong immunosuppressive treatment, OLTx recipients can develop an early, multispecific, preferentially intrahepatic CD4+ T cell response that decreases over time, making it a potential candidate target for novel therapeutic approaches in the transplant setting.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Hepacivirus/immunology , Hepatitis C/immunology , Liver Transplantation/immunology , Antibody Formation , Biopsy , Cell Culture Techniques , Cell Line , Enzyme-Linked Immunosorbent Assay , Female , Genotype , Graft Rejection/immunology , Graft Rejection/pathology , Hepacivirus/genetics , Hepatitis C/surgery , Hepatitis C Antibodies/analysis , Hepatitis C Antibodies/blood , Humans , Interferon-gamma/biosynthesis , Liver/immunology , Liver Failure/etiology , Liver Failure/surgery , Liver Function Tests , Liver Transplantation/pathology , Liver Transplantation/physiology , Male , Middle Aged , RNA, Viral/analysis , Recurrence , Time Factors
20.
Transplantation ; 71(2): 334-7, 2001 Jan 27.
Article in English | MEDLINE | ID: mdl-11213083

ABSTRACT

BACKGROUND: Microsporidia are common pathogens among patients infected with human immunodeficiency virus. They account for a substantial proportion of chronic diarrhea and malabsorption in acquired immune deficiency syndrome, but their appearance after solid organ transplantation has only rarely been reported. Methods. We report what we believe is the first case of documented Enterocytozoon bieneusi infection in a liver transplant recipient. Results. Our patient presented with chronic diarrhea and colicky abdominal pain. Although symptoms were severe, only mild microscopical mucosal changes were found in the intestinal tract. A modified trichrome stain of stool specimens revealed microsporidial spores, and species differentiation by restriction fragment length polymorphism polymerase chain reaction identified Enterocytozoon bieneusi. Albendazole therapy brought symptomatic relief but no microbiological clearance. CONCLUSIONS: Enterocytozoon bieneusi may cause chronic diarrhea not only in immunosuppression as a result of human immunodeficiency virus infection but also among patients with therapeutic immunosuppression after organ transplantation. Therefore, microsporidial infection should be considered in immunosuppressed patients with otherwise unexplained diarrhea.


Subject(s)
Diarrhea/etiology , Intestines/parasitology , Liver Transplantation/adverse effects , Microsporida , Microsporidiosis/complications , Adult , Albendazole/therapeutic use , Animals , Chronic Disease , Feces/parasitology , Female , Humans , Microsporidiosis/drug therapy
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