RESUMEN
Age-related changes in the posterior extensor muscles of the cervical and lumbar spine have been reported in some studies; however, longitudinal changes in the thoracic spine of healthy subjects are rarely reported. Therefore, this study aimed to evaluate changes in the cross-sectional areas (CSAs) of posterior extensor muscles in the thoracic spine over 10 years and identify related factors. The subjects of this study were 85 volunteers (mean age: 44.7 ± 11.5) and the average follow-up period was about 10 years. The CSAs of the transversospinalis muscles, erector spinae muscles, and total CSAs of the extensor muscles from T1/2 to T11/12 were measured on magnetic resonance imaging. The extent of muscle fat infiltration was assessed by the signal intensity (luminance) of the extensor muscles' total cross-section compared to a section of pure muscle. We applied a Poisson regression model, which is included in the generalized linear model, and first examined the univariate (crude) association between each relevant factor (age, sex, body mass index, lifestyle, back pain, neck pain, neck stiffness, and intervertebral disc degeneration) and CSA changes. Then, we constructed a multivariate model, which included age, sex, and related factors in the univariate analysis. The mean CSAs of the transversospinalis muscles, erector spinae muscles, and total CSAs of the extensor muscles significantly increased over 10 years. Exercise habit was associated with increased CSAs of the erector spinae muscles and the total area of the extensor muscles. The cross-section mean luminance significantly increased from baseline, indicating a significant increase of fat infiltration in the posterior extensor muscles. Progression of disc degeneration was inversely associated with increased fat infiltration in the total extensor muscles.
Asunto(s)
Degeneración del Disco Intervertebral , Dolor de Cuello , Adulto , Humanos , Degeneración del Disco Intervertebral/patología , Vértebras Lumbares , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Dolor de Cuello/patología , Músculos Paraespinales/diagnóstico por imagen , Músculos Paraespinales/patologíaRESUMEN
To prevent infections associated with medical implants, various antimicrobial silver-coated implant materials have been developed. However, these materials do not always provide consistent antibacterial effects in vivo despite having dramatic antibacterial effects in vitro, probably because the antibacterial effects involve silver-ion-mediated reactive oxygen species generation. Additionally, the silver application process often requires extremely high temperatures, which damage non-metal implant materials. We recently developed a bacteria-resistant coating consisting of hydroxyapatite film on which ionic silver is immobilized via inositol hexaphosphate chelation, using a series of immersion and drying steps performed at low heat. Here we applied this coating to a polymer, polyetheretherketone (PEEK), and analyzed the properties and antibacterial activity of the coated polymer in vitro and in vivo. The ionic silver coating demonstrated significant bactericidal activity and prevented bacterial biofilm formation in vitro. Bio-imaging of a soft tissue infection mouse model in which a silver-coated PEEK plate was implanted revealed a dramatic absence of bacterial signals 10 days after inoculation. These animals also showed a strong reduction in histological features of infection, compared to the control animals. This innovative coating can be applied to complex structures for clinical use, and could prevent infections associated with a variety of plastic implants.
Asunto(s)
Biopelículas/efectos de los fármacos , Materiales Biocompatibles Revestidos/farmacología , Prótesis e Implantes/microbiología , Infecciones Estafilocócicas/prevención & control , Animales , Antibacterianos/química , Antibacterianos/farmacología , Benzofenonas/química , Benzofenonas/farmacología , Durapatita/química , Durapatita/farmacología , Humanos , Nanopartículas del Metal/química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Ratones , Polímeros/química , Polímeros/farmacología , Especies Reactivas de Oxígeno/metabolismo , Plata/química , Plata/farmacología , Infecciones Estafilocócicas/microbiologíaRESUMEN
STUDY DESIGN: A longitudinal, 20-year comparative study of patients with whiplash-associated disorders (WAD). OBJECTIVE: The aim of this study was to clarify the long-term impact of WAD on patient symptoms and on magnetic resonance imaging (MRI) findings of the cervical spine, in comparison with asymptomatic volunteers. SUMMARY OF BACKGROUND DATA: The long-term impact of WAD has not been fully elucidated. METHODS: Between 1993 and 1996, we conducted a cross-sectional comparative study of 508 acute WAD patients and 497 asymptomatic volunteers, all of whom underwent MRI on cervical spine and physical examinations. For this 20-year follow-up comparative study, 75 WAD patients and 181 control subjects aged <60âyears were recruited from the original cohort. The MRI findings, including discs' signal intensities, posterior disc protrusions, anterior dural compressions, spinal cord disc space narrowing, and foraminal stenoses, were evaluated using two to four numerical grades. The results of the WAD patients and control subjects were compared. RESULTS: In this follow-up, the prevalence of shoulder stiffness (72.0% vs. 45.9%), headache (24.0% vs. 12.2%), and arm pain (13.3% vs. 3.9%) were significantly greater in WAD patients than in control subjects. The multiregression analysis revealed that a history of WAD was associated with shoulder stiffness (odds ratio [OR]: 3.36), headache (OR: 2.39), and arm pain (OR: 3.82). Although MRI findings in WAD patients were more degenerated than in control subjects in the initial study, all MRI findings were similar at the 20-year follow-up. There were no significant correlations between clinical cervical symptoms and progression in each MR finding in either group. CONCLUSION: After 20âyears, whiplash injuries significantly impacted the residual symptoms of shoulder stiffness, headache, and arm pain when compared with initially asymptomatic volunteers. The progression of degenerative changes in the cervical intervertebral discs after 20âyears revealed no association with existing whiplash injuries, neither did the residual cervical-related symptoms.Level of Evidence: 3.
Asunto(s)
Lesiones por Latigazo Cervical , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Cuello/diagnóstico por imagen , Cuello/fisiopatología , Dolor de Cuello/diagnóstico por imagen , Dolor de Cuello/epidemiología , Dolor de Cuello/etiología , Hombro/diagnóstico por imagen , Hombro/fisiopatología , Lesiones por Latigazo Cervical/complicaciones , Lesiones por Latigazo Cervical/diagnóstico por imagen , Lesiones por Latigazo Cervical/epidemiologíaRESUMEN
Osteomyelitis, which often arises from a surgical-site infection, is a serious problem in orthopaedic surgery. However, there are no specific biomarkers for osteomyelitis. Here, to identify specific plasma biomarkers for osteomyelitis, we conducted metabolome analyses using a mouse osteomyelitis model and bioluminescence imaging. We divided adult male pathogen-free BALB/C mice into control, sham-control, and infected groups. In the infected group, a bioluminescent Staphylococcus aureus strain was inoculated into the femur, and osteomyelitis was detected by bioluminescence imaging. We next analysed the metabolome, by comprehensively measuring all of the small molecules. This analysis identified 279 metabolites, 12 of which were significantly higher and 45 were significantly lower in the infected group than in the sham-control and control groups. Principal component analysis identified sphingosine as the highest loading factor. Several acyl carnitines and fatty acids, particularly ω-3 and ω-6 polyunsaturated fatty acids, were significantly lower in the infected group. Several metabolites in the tricarboxylic acid cycle were lower in the infected group than in the other groups. Thus, we identified two sphingolipids, sphinganine and sphingosine, as positive biomarkers for mouse osteomyelitis, and two components in the tricarboxylic acid cycle, two-oxoglutarate and succinic acid, as negative biomarkers.
Asunto(s)
Metaboloma , Osteomielitis/diagnóstico , Esfingolípidos/sangre , Esfingosina/análogos & derivados , Esfingosina/sangre , Animales , Biomarcadores/sangre , Carnitina/análogos & derivados , Carnitina/sangre , Ciclo del Ácido Cítrico , Modelos Animales de Enfermedad , Ácidos Grasos/sangre , Ácidos Cetoglutáricos/sangre , Mediciones Luminiscentes , Masculino , Ratones Endogámicos BALB C , Osteomielitis/etiología , Osteomielitis/microbiología , Infecciones Estafilocócicas , Staphylococcus aureus , Ácido Succínico/sangre , Infección de la Herida Quirúrgica/complicacionesRESUMEN
STUDY DESIGN: Prospective longitudinal study. OBJECTIVE: The aim of this study was to evaluate long-term degenerative changes in intervertebral discs in the thoracic spine in healthy asymptomatic subjects. SUMMARY OF BACKGROUND DATA: Longitudinal magnetic resonance imaging (MRI) studies of intervertebral disc degeneration have been reported for the cervical and lumbar but not the thoracic spine. METHODS: In this longitudinal study (average follow-up 10.0â±â0.6 years), we assessed degenerative changes in the thoracic spine of 103 volunteers (58 men) of 223 healthy volunteers in the initial MRI study of the thoracic spine (follow-up rate 46.2%). The mean age at the initial study was 45.0â±â11.5 years (24-77 years). Initial and follow-up thoracic-spine MRIs were graded for the following 4 factors of degenerative changes: decrease in signal intensity of intervertebral disc (DSI), posterior disc protrusion (PDP), anterior compression of dura and spinal cord (AC), and disc-space narrowing (DSN) from T1-2 to T12-L1. We assessed associations between changes in MRI grade and demographical factors such as age, sex, body mass index, smoking habits, sports activities, and disc degeneration in the cervical spine. RESULTS: MRIs revealed that 63.1% of the subjects had degenerative changes in the thoracic intervertebral discs that had progressed at least one grade during the follow-up period. DSI progressed in 44.7% of subjects, PDP in 21.4%, and AC in 18.4% during the 10-year period. No DSN progression was seen. DSI was frequently observed in the upper thoracic spine (T1-2 to T4-5). Disc degeneration was relatively scarce in the lower thoracic spine (T9-10 to T12-L1). PDP was frequently observed in the middle thoracic spine (T5-6 toT8-9). We found significant associations between DSI and cervical-spine degeneration (Pâ=â.004) and between AC and smoking (Pâ=â.04). CONCLUSION: Progressive thoracic disc degeneration, observed in 63.1% of subjects; was significantly associated with smoking and with cervical-spine degeneration. LEVEL OF EVIDENCE: 2.
Asunto(s)
Envejecimiento/fisiología , Degeneración del Disco Intervertebral , Disco Intervertebral , Vértebras Torácicas , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Disco Intervertebral/diagnóstico por imagen , Disco Intervertebral/patología , Degeneración del Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/patología , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/patología , Adulto JovenRESUMEN
BACKGROUND: Few studies have characterized the development of Modic changes in the cervical spine over time. We evaluated Modic changes of the cervical spine that developed over a 20-year period in a healthy cohort, and sought to clarify the relationship between Modic changes and the development of clinical symptoms. METHODS: For this multicenter prospective cohort study, we recruited 193 subjects from an original cohort of asymptomatic volunteers who underwent MRI of the cervical spine between 1993 and 1996. Each cervical level from C2/3 to C7/T1 (total n = 1158 intervertebral levels) was assessed on current MRIs as normal or showing type 1, 2, or 3 Modic change, and we asked about symptoms related to the cervical spine. Relationships between the presence of Modic changes and patient characteristics, pre-existing disc degenerations or clinical symptoms were evaluated by logistic regression analysis. RESULTS: After 20-year follow-up, Modic changes affected 31 subjects (16.1%) at 47 intervertebral disc levels. Of these 47 intervertebral disc levels, type 2, found at 30 levels (63.8%), was the most frequent, followed by type 1 at 15 levels (31.9%) and type 3 at two levels (4.3%). The most frequent changes were observed at the C5/6 segment with type 2 Modic changes. The presence of Modic changes correlated with pre-existing posterior disc protrusion (odds ratio 3.31, 95% confidence interval 1.21-9.05) and neck pain (odds ratio 2.71, 95% confidence interval 1.08-6.80). CONCLUSIONS: In the cervical spine over a 20-year period, type 2 Modic changes were most frequent at the C5/6 segment. The Modic changes were associated with pre-existing disc degeneration and neck pain but not with age, BMI, smoking, shoulder stiffness, arm pain or numbness.
Asunto(s)
Vértebras Cervicales , Degeneración del Disco Intervertebral/etiología , Dolor de Cuello/etiología , Adolescente , Adulto , Factores de Edad , Anciano , Niño , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Humanos , Degeneración del Disco Intervertebral/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Dolor de Cuello/diagnóstico por imagen , Factores de Tiempo , Adulto JovenRESUMEN
BACKGROUND: Some patients suffer from long-lasting symptoms after whiplash injury. However, there are few reports on the long-term changes in the cervical spine after whiplash injury using imaging tests. The purpose of this longitudinal study was to determine the changes on MRI of the cervical spine 20 years after whiplash injury, and to examine the relationships between changes in the cervical spine on MRI and changes in related clinical symptoms. METHODS: Eighty-one subjects finally participated in this study (follow-up rate 16%). The mean follow-up duration was 21.7 years. All subjects filled out a questionnaire about their clinical symptoms. The MRI findings were assessed using numerical grading system applied in the original study. Statistic analyses were used to investigate whether the progression of each MRI finding was associated with the severity of neck pain, stiff shoulders, dizziness and tinnitus. RESULTS: All subjects had complained of some clinical symptoms in the original study: 71 had neck pain, 53 stiff shoulders, and others. In the present study, 66 subjects (81.5%) complained of some clinical symptoms: 57 had stiff shoulders, 20 neck pain, and others. The progression of degeneration on MRI was observed in 95% of the subjects, with C4/5 and 5/6 being the most frequently involved levels. Changes in the severity of neck pain, stiff shoulders, dizziness and tinnitus over 20 years were not significantly associated with the progression of degenerative changes in the cervical spine on MRI. CONCLUSIONS: Twenty years after whiplash injury, 95% of the subjects showed a progression of degeneration in the cervical spine. The progression of the intervertebral disc degeneration in the cervical spine on MRI after whiplash injury was not significantly associated with changes in the severity of related clinical symptoms, indicating that the degenerative changes on MRI may reflect the physiological aging process rather than post-traumatic sequelae.
Asunto(s)
Vértebras Cervicales , Dolor de Cuello/diagnóstico por imagen , Lesiones por Latigazo Cervical/complicaciones , Lesiones por Latigazo Cervical/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Dolor de Cuello/etiología , Encuestas y Cuestionarios , Evaluación de Síntomas , Factores de TiempoRESUMEN
STUDY DESIGN: A 20-year longitudinal study. OBJECTIVE: To evaluate the long-term effect of sagittal alignment of the cervical spine on intervertebral disk degeneration in healthy asymptomatic subjects. SUMMARY OF BACKGROUND DATA: This study continues a previous 10-year longitudinal study to determine whether sagittal alignment affects disk degeneration during normal aging. MATERIALS AND METHODS: We assessed 90 healthy subjects (30 men and 60 women) from among 497 volunteers who underwent magnetic resonance imaging (MRI) and plain radiographs of the cervical spine between 1994 and 1996 (follow-up rate 18.1%). The mean age at the initial study was 35.5±13.4 years (11-65 y). We compared initial MRIs and follow-up MRIs, conducted at an average of 21.6 years after the initial study, for (1) decreased signal intensity of the intervertebral disks, (2) posterior disk protrusion, and (3) disk-space narrowing from C2-3 to C7-T1. Subjects were grouped by age at follow-up (under 40 vs. 40 y and older) and by a lordotic or nonlordotic cervical sagittal alignment at baseline. We assessed neck pain, stiff shoulders, and upper-arm numbness at follow-up, and examined associations between clinical symptoms and MRI parameters. RESULTS: Progressive changes during the 20-year period included a decrease in disk signal intensity (84.4% of subjects), posterior disk protrusion (86.7%), and disk-space narrowing (17.8%). No significant association was observed between sagittal alignment and decreased disk signal intensity, posterior disk protrusion, or disk-space narrowing. Among subjects over the age of 40, progressive degenerative changes at C7-T1 were significantly more frequent in nonlordotic subjects (90.9%) compared with those with cervical lordosis (54.2%, P=0.032). The prevalence of clinical symptoms was similar in lordotic and nonlordotic subjects at follow-up. CONCLUSIONS: Nonlordotic cervical alignment was related to the progression of disk degeneration at C7-T1 but not other levels. Cervical alignment did not affect the development of clinical symptoms in healthy subjects. LEVEL OF EVIDENCE: Level III.
Asunto(s)
Vértebras Cervicales , Degeneración del Disco Intervertebral/cirugía , Adolescente , Adulto , Anciano , Envejecimiento , Niño , Femenino , Estudios de Seguimiento , Humanos , Degeneración del Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/fisiopatología , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Postura , Sobrevivientes , Adulto JovenRESUMEN
BACKGROUND: Few studies have addressed in detail long-term degenerative changes in the cervical spine. In this study, we evaluated the progression of degenerative changes of the cervical spine that occurred over a 20-year period in an originally healthy cohort. We also sought to clarify the relationship between the progression of cervical degenerative changes and the development of clinical symptoms. METHODS: For this prospective follow-up investigation, we recruited 193 subjects from an original cohort of 497 participants who had undergone magnetic resonance imaging (MRI) of the cervical spine between 1993 and 1996. The subjects were asked about the presence or absence of cervical spine-related symptoms. Degenerative changes of the cervical spine were assessed on MRI using an original numerical grading system. The relationship between the progression of degenerative changes and the onset of clinical symptoms was evaluated by logistic regression analysis. RESULTS: Degeneration in the cervical spine was found to have progressed in 95% of the subjects during the 20-year period. The finding of a decrease in signal intensity of the intervertebral disc progressed in a relatively high proportion of the subjects in all age groups and occurred with similar frequency (around 60%) at all intervertebral disc levels. The rate of progression of other structural failures on MRI increased with age and was highest at C5-C6. The progression of foraminal stenosis was associated with the onset of upper-limb pain (odds ratio, 4.71 [95% confidence interval, 1.02 to 21.7]). CONCLUSIONS: A progression of degenerative changes in the cervical spine on MRI over the 20-year period was detected in nearly all subjects. There was no relationship between the progression of degeneration on MRI and the development of clinical symptoms, with the exception of an association found between foraminal stenosis and upper-limb pain. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Asunto(s)
Vértebras Cervicales , Progresión de la Enfermedad , Degeneración del Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/patología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Degeneración del Disco Intervertebral/complicaciones , Modelos Logísticos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Evaluación de Síntomas , Factores de TiempoRESUMEN
Whether Propionibacterium acnes (P. acnes) causes surgical-site infections (SSI) after orthopedic surgery is controversial. We previously reported that we frequently find P. acnes in intraoperative specimens, yet none of the patients have clinically apparent infections. Here, we tracked P. acnes for 6 months in a mouse osteomyelitis model. We inoculated P. acnes with an implant into the mouse femur in the implant group; the control group was treated with the bacteria but no implant. We then observed over a 6-month period using optical imaging system. During the first 2 weeks, bacterial signals were detected in the femur in the both groups. The bacterial signal completely disappeared in the control group within 28 days. Interestingly, in the implant group, bacterial signals were still present 6 months after inoculation. Histological and scanning electron-microscope analyses confirmed that P. acnes was absent from the control group 6 months after inoculation, but in the implant group, the bacteria had survived in a biofilm around the implant. PCR analysis also identified P. acnes in the purulent effusion from the infected femurs in the implant group. To our knowledge, this is the first report showing that P. acnes causes SSI only in the presence of an implant.
Asunto(s)
Infecciones por Bacterias Grampositivas/diagnóstico por imagen , Osteomielitis/cirugía , Propionibacterium acnes/fisiología , Prótesis e Implantes/microbiología , Infección de la Herida Quirúrgica/microbiología , Animales , Adhesión Bacteriana , Biopelículas/crecimiento & desarrollo , Modelos Animales de Enfermedad , Fémur/diagnóstico por imagen , Fémur/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Ratones , Imagen Óptica , Infección de la Herida Quirúrgica/diagnóstico por imagenRESUMEN
Musculoskeletal infections, including surgical-site and implant-associated infections, often cause progressive inflammation and destroy areas of the soft tissue. Treating infections, especially those caused by multi-antibiotic resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) remains a challenge. Although there are a few animal models that enable the quantitative evaluation of infection in soft tissues, these models are not always reproducible or sustainable. Here, we successfully established a real-time, in vivo, quantitative mouse model of soft-tissue infection in the superficial gluteus muscle (SGM) using bioluminescence imaging. A bioluminescent strain of MRSA was inoculated into the SGM of BALB/c adult male mice, followed by sequential measurement of bacterial photon intensity and serological and histological analyses of the mice. The mean photon intensity in the mice peaked immediately after inoculation and remained stable until day 28. The serum levels of interleukin-6, interleukin-1 and C-reactive protein at 12 hours after inoculation were significantly higher than those prior to inoculation, and the C-reactive protein remained significantly elevated until day 21. Histological analyses showed marked neutrophil infiltration and abscesses containing necrotic and fibrous tissues in the SGM. With this SGM mouse model, we successfully visualized and quantified stable bacterial growth over an extended period of time with bioluminescence imaging, which allowed us to monitor the process of infection without euthanizing the experimental animals. This model is applicable to in vivo evaluations of the long-term efficacy of novel antibiotics or antibacterial implants.
Asunto(s)
Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones de los Tejidos Blandos/diagnóstico , Infecciones Estafilocócicas/diagnóstico , Staphylococcus aureus/aislamiento & purificación , Animales , Diagnóstico por Imagen , Modelos Animales de Enfermedad , Mediciones Luminiscentes , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Ratones , Ratones Endogámicos BALB C , Infecciones de los Tejidos Blandos/microbiología , Infecciones de los Tejidos Blandos/patología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/patología , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/patogenicidadRESUMEN
STUDY DESIGN: Case report. OBJECTIVE: To report an extremely rare case of spinal dumbbell-type tanycyticependymoma. SUMMARY OF BACKGROUND DATA: Only two previous cases of a dumbbell-type tanycyticependymoma in the spinal cordhave been reported. METHODS: A 40-year-old female presented with low back pain and numbness of the left leg. Magnetic resonance imaging revealed a dumbbell tumor at the Th10-11 level that compressed the spinal cord extensively. The diagnosis of extradural dumbell spinal tumor was made, and a total tumor excision was performed with a thoracic 10-11 laminectomy. RESULTS: After surgery, the patient's low back pain and numbness disappeared. Detailed immunohistological examinations confirmed the diagnosis of tanycyticependymoma. At 16 months, there was no evidence of tumor recurrence and no further treatment was needed. CONCLUSION: A rare case of spinal dumbbell-type tanycyticependy-moma was presented. Detailed histologic examinations are essential to differentiate tanycyticependymoma from other tumors such as schwannoma and pilocyticastrocytoma.
Asunto(s)
Ependimoma/diagnóstico , Neoplasias de la Médula Espinal/diagnóstico , Vértebras Torácicas , Adulto , Ependimoma/complicaciones , Ependimoma/cirugía , Femenino , Humanos , Laminectomía , Dolor de la Región Lumbar/etiología , Neoplasias de la Médula Espinal/complicaciones , Neoplasias de la Médula Espinal/cirugía , Resultado del TratamientoRESUMEN
We studied the movement of center of gravity (CG) in young and aged subjects during maximum grip of right or left hand. Body-sway was recorded with stabilometry in rest-stand position and in maximum grip. The data from right-or left-handed young subjects were analyzed. Maximum grip power was not different between dominant hand and un-dominant hands. Total length (LNG) and total movement area of CG (REC AREA) during the measurements were significantly larger in maximum grip than in rest-stand. In right-handed subjects, LNG increased to 245% and 250% of rest-stand value, and REC AREA increased to 589% and 633% in right and left hand grip, respectively. In left-handed subjects, LNG increased to 186% and 188% of rest-stand value, and REC AREA increased to 400% and 533% in right and left hand grip, respectively. No significant difference of LNG and REC AREA was observed between right and left hand grip in either hand dominant subject Maximum grip did not affect CG in rest-stand. In aged subjects, maximum grip power was significantly less than in young subjects (48%). LNG and REC AREA in rest-stand were significantly larger in aged subjects than in young subjects (220% and 400%, respectively). They were not different during maximum grip with either hand. While aged subjects have difficulty of controlling CG in rest-stand, they have less problems to stabilize CG during maximum grip. These data indicated that dynamic movement of CG might be important to understand person's activity of daily living.
Asunto(s)
Fuerza de la Mano , Movimiento , Equilibrio Postural , Actividades Cotidianas , Adulto , Factores de Edad , Anciano , Femenino , Lateralidad Funcional , Humanos , MasculinoRESUMEN
We examined the effects of loxoprofen, a cyclooxygenase inhibitor, and ONO-8711, an EP1-receptor antagonist, on afferent nerve activity during acetic acid (AA, 0.1% v/v)-induced inflammation of the rat urinary bladder. Distension stimulation was performed (vesical pressure of 30 cm H2O) for 2 min. The neuronal discharge was recorded from L6 dorsal root filaments. The discharge was observed just after the beginning of distension and increased gradually thereafter. When the vesical pressure returned to control value, the discharge diminished abruptly. AA infusion increased the total number of spikes to 198 +/- 38.8% of control values. AA infusion also produced asynchronous discharge in 39% of the animals. Loxoprofen administration (1 mg/kg, i.v.) reduced the number of spikes to 40.3 +/- 14.8% of control values. ONO-8711 administration (1 and 3 mg/kg, i.v.) reduced the number of spikes to 81.6 +/- 1.6% and 32.2 +/- 7.4% of control values, respectively. These data indicate that loxoprofen or EP1-receptor antagonist inhibit the inflammation-related neuronal activity. EP1 receptors in the peripheral afferent nerve terminal and/or urothelium may facilitate the primary afferent nerve activity, which elicits the inflammation-induced micturition reflex.
Asunto(s)
Vías Aferentes , Antiinflamatorios no Esteroideos/farmacología , Compuestos Bicíclicos con Puentes/farmacología , Caproatos/farmacología , Fenilpropionatos/farmacología , Prostaglandinas E/metabolismo , Receptores de Prostaglandina E/metabolismo , Vejiga Urinaria , Ácido Acético/farmacología , Vías Aferentes/efectos de los fármacos , Vías Aferentes/metabolismo , Animales , Femenino , Inflamación , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Ratas , Ratas Wistar , Receptores de Prostaglandina E/antagonistas & inhibidores , Subtipo EP1 de Receptores de Prostaglandina E , Vejiga Urinaria/efectos de los fármacos , Vejiga Urinaria/inervación , Vejiga Urinaria/patologíaRESUMEN
PURPOSE: Previous studies have revealed that the activation of alpha(1) adrenergic receptors in urothelial cells releases neurotransmitters. We determined if alpha(1D) adrenergic receptors are expressed in the urothelium of the rat bladder and if inhibition of these receptors affects reflex voiding. MATERIALS AND METHODS: Female Wistar rats were used in the experiments. Receptor expression was evaluated by Western blot. The effects of receptor activation were studied using cystometrograms, measurement of adenosine triphosphate concentrations in the bladder lumen and afferent nerve recording. The alpha(1D) antagonist naftopidil (0.75 to 1.66 mg/kg) was administered intravenously into the external jugular vein. RESULTS: The expression of alpha(1D) adrenergic receptors was detected in urothelial tissue with Western blot and immunohistochemistry. The alpha(1D) receptor antagonist naftopidil prolonged the intercontraction interval during continuous infusion cystometrograms in conscious rats (143% of the control value) and suppressed the excitatory effect of intravesical infusion of acetic acid (0.1%) on the intercontraction interval (220%). Naftopidil inhibited the bladder afferent nerve activity induced by bladder distention (32.0%) and acetic acid infusion (30.4%), and decreased adenosine triphosphate levels in the bladder perfusate during bladder distention (36.6%). CONCLUSIONS: Endogenous catecholamines appear to act on alpha(1D) receptors in the urothelium to facilitate mechanosensitive bladder afferent nerve activity and reflex voiding.