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1.
J Eur Acad Dermatol Venereol ; 36(3): 391-402, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34862986

RESUMEN

BACKGROUND: Early diagnosis is the most effective intervention to improve the prognosis of cutaneous melanoma. Even though the introduction of dermoscopy has improved the diagnostic accuracy, it can still be difficult to distinguish some melanomas from benign melanocytic lesions. Digital dermoscopy monitoring can identify dynamic changes of melanocytic lesions: To date, some algorithms were proposed, but a universally accepted one is still lacking. OBJECTIVES: To identify independent predictive variables associated with the diagnosis of cutaneous melanoma and develop a multivariable dermoscopic prediction model able to discriminate benign from malignant melanocytic lesions undergoing digital dermoscopy monitoring. METHODS: We collected dermoscopic images of melanocytic lesions excised after dermoscopy monitoring and carried out static and dynamic evaluations of dermoscopic features. We built two multivariable predictive models based on logistic regression and random forest. RESULTS: We evaluated 173 lesions (65 cutaneous melanomas and 108 nevi). Forty-two melanomas were in situ, and the median thickness of invasive melanomas was 0.35 mm. The median follow-up time was 9.8 months for melanomas and 9.1 for nevi. The logistic regression and random forest models performed with AUC values of 0.87 and 0.89, respectively, were substantially higher than those of the static evaluation models (ABCD TDS score, 0.57; 7-point checklist, 0.59). Finally, we built two risk calculators, which translate the proposed models into user-friendly applications, to assist clinicians in the decision-making process. CONCLUSIONS: The present study demonstrates that the integration of dynamic and static evaluations of melanocytic lesions is a safe approach that can significantly boost the diagnostic accuracy for cutaneous melanoma. We propose two diagnostic tools that significantly increase the accuracy in discriminating melanoma from nevi during digital dermoscopy monitoring.


Asunto(s)
Melanoma , Nevo , Neoplasias Cutáneas , Dermoscopía/métodos , Humanos , Melanocitos/patología , Melanoma/diagnóstico por imagen , Melanoma/patología , Nevo/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/patología
2.
Br J Dermatol ; 184(4): 722-730, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32479678

RESUMEN

BACKGROUND: The PROspective Cutaneous Lymphoma International Prognostic Index (PROCLIPI) study is a prospective analysis of an international database. Here we examine front-line treatments and quality of life (QoL) in patients with newly diagnosed mycosis fungoides (MF). OBJECTIVES: To identify (i) differences in first-line approaches according to tumour-nodes-metastasis-blood (TNMB) staging; (ii) parameters related to a first-line systemic approach and (iii) response rates and QoL measures. METHODS: In total, 395 newly diagnosed patients with early-stage MF (stage IA-IIA) were recruited from 41 centres in 17 countries between 1 January 2015 and 31 December 2018 following central clinicopathological review. RESULTS: The most common first-line therapy was skin-directed therapy (SDT) (322 cases, 81·5%), while a smaller percentage (44 cases, 11·1%) received systemic therapy. Expectant observation was used in 7·3%. In univariate analysis, the use of systemic therapy was significantly associated with higher clinical stage (IA, 6%; IB, 14%; IIA, 20%; IA-IB vs. IIA, P < 0·001), presence of plaques (T1a/T2a, 5%; T1b/T2b, 17%; P < 0·001), higher modified Severity Weighted Assessment Tool (> 10, 15%; ≤ 10, 7%; P = 0·01) and folliculotropic MF (FMF) (24% vs. 12%, P = 0·001). Multivariate analysis demonstrated significant associations with the presence of plaques (T1b/T2b vs. T1a/T2a, odds ratio 3·07) and FMF (odds ratio 2·83). The overall response rate (ORR) to first-line SDT was 73%, while the ORR to first-line systemic treatments was lower (57%) (P = 0·027). Health-related QoL improved significantly both in patients with responsive disease and in those with stable disease. CONCLUSIONS: Disease characteristics such as presence of plaques and FMF influence physician treatment choices, and SDT was superior to systemic therapy even in patients with such disease characteristics. Consequently, future treatment guidelines for early-stage MF need to address these issues.


Asunto(s)
Micosis Fungoide , Neoplasias Cutáneas , Humanos , Micosis Fungoide/patología , Micosis Fungoide/terapia , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos , Calidad de Vida , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/terapia
3.
Epidemiol Infect ; 144(13): 2719-27, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26522501

RESUMEN

In 2012 a US multistate outbreak of listeriosis was linked to ricotta salata imported from Italy, made from pasteurized sheep's milk. Sampling activities were conducted in Italy to trace the source of Listeria monocytogenes contamination. The cheese that caused the outbreak was produced in a plant in Apulia that processed semi-finished cheeses supplied by five plants in Sardinia. During an 'emergency sampling', 179 (23·6%) out of 758 end-products tested positive for L. monocytogenes, with concentrations from <10 c.f.u./g to 1·1 × 106 c.f.u./g. Positive processing environment samples were found in two out of four processing plants. A 'follow-up sampling' was conducted 8 months later, when environmental samples from three out of six plants tested positive for L. monocytogenes and for Listeria spp. PFGE subtyping showed 100% similarity between US clinical strains and isolates from ricotta salata, confirming the origin of the outbreak. The persistence of strains in environmental niches of processing plants was demonstrated, and is probably the cause of product contamination. Two PFGE profiles from clinical cases of listeriosis in Italy in 2011, stored in the MSS-TESSy database, were found to have 100% similarity to one PFGE profile from a US clinical case associated with the consumption of ricotta salata, according to the US epidemiological investigation (sample C, pulsotype 17). However, they had 87% similarity to the only PFGE profile found both in the US clinical case and in 14 ricotta cheese samples collected during the emergency sampling (sample B, pulsotype 1). Sharing of molecular data and availability of common characterization protocols were key elements that connected the detection of the US outbreak to the investigation of the food source in Italy. Simultaneous surveillance systems at both food and human levels are a necessity for the efficient rapid discovery of the source of an outbreak of L. monocytogenes.


Asunto(s)
Queso/microbiología , Brotes de Enfermedades , Manipulación de Alimentos , Microbiología de Alimentos , Listeria monocytogenes/aislamiento & purificación , Listeriosis/epidemiología , Proteínas Bacterianas/genética , Electroforesis en Gel de Campo Pulsado , Italia , Listeria monocytogenes/clasificación , Listeriosis/microbiología , Filogenia , Análisis de Secuencia de ADN , Estados Unidos/epidemiología
4.
Nutr Metab Cardiovasc Dis ; 23(9): 864-70, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22901845

RESUMEN

BACKGROUND AND AIMS: It is not clear whether the metabolic syndrome (MetS) is a distinct entity or a combination of risk factors. Several studies showed the association between MetS and cardiovascular disease (CVD). Subclinical target organ damage (TOD) is a recognized marker of atherosclerosis and predictor of cardiovascular events. Increased burden of subclinical atherosclerosis was detected in individuals with MetS. We thus aimed to examine the association between MetS and cumulative or specific TOD and to assess whether MetS predicts TOD better than the risk factors included in current definitions. METHODS AND RESULTS: We recorded TOD in 979 patients at intermediate cardiovascular risk with and without MetS according to IDF and NCEP criteria. We measured common carotid intima-media thickness, left ventricular mass index (LVMI), urine albumin to creatinine ratio (UACR), and ankle-brachial index. We found no correlation between having at least one TOD and being positive for MetS. A high UACR was associated with MetS using both IDF and NCEP criteria, while only NCEP identified individuals with increased LVMI. Using a multivariate logistic regression model including MetS, age, sex, waist circumference, triglycerides, HDL cholesterol, blood pressure and blood glucose levels we found no correlations between the presence of MetS and at least one TOD. The associations with high UACR and LVMI disappeared when age, blood pressure and glycemia were counted in. CONCLUSION: Although MetS showed some relation with subclinical renal and cardiac damage, it does not predict TOD any better than the risk factors specified in the definitions.


Asunto(s)
Enfermedades Cardiovasculares/fisiopatología , Síndrome Metabólico/fisiopatología , Enfermedad Arterial Periférica/fisiopatología , Adulto , Anciano , Albuminuria/etiología , Albuminuria/fisiopatología , Índice Tobillo Braquial , Presión Sanguínea , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/diagnóstico por imagen , Grosor Intima-Media Carotídeo , HDL-Colesterol/sangre , Creatinina/orina , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Masculino , Síndrome Metabólico/complicaciones , Síndrome Metabólico/diagnóstico por imagen , Persona de Mediana Edad , Análisis Multivariante , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/etiología , Factores de Riesgo , Cardiomiopatía de Takotsubo/diagnóstico por imagen , Cardiomiopatía de Takotsubo/fisiopatología , Triglicéridos/sangre
5.
Cell Death Differ ; 15(7): 1103-12, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18552861

RESUMEN

The HECT-type E3 ubiquitin ligase (E3) Itch is absent in the non-agouti-lethal 18H or Itchy mice, which develop a severe immunological disease, including lung and stomach inflammation and hyperplasia of lymphoid and hematopoietic cells. The involvement of Itch in multiple signaling pathways and pathological conditions is presently an area of extensive scientific interest. This review aims to bring together a growing body of work exploring Itch-regulated biological processes, and to highlight recent discoveries on the regulatory mechanisms modulating its catalytic activity and substrate recognition capability. Our contribution is also an endeavor to correlate Itch substrate specificity with the pathological defects manifested by the mutant Itchy mice.


Asunto(s)
Sistema Inmunológico/metabolismo , Neoplasias/enzimología , Proteínas Represoras/metabolismo , Piel/enzimología , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Muerte Celular , Receptores ErbB/metabolismo , Sistema Inmunológico/patología , Queratinocitos/metabolismo , Ratones , Ratones Mutantes , Neoplasias/inmunología , Neoplasias/patología , Fosforilación , Transporte de Proteínas , Receptores de Quimiocina/metabolismo , Proteínas Represoras/inmunología , Transducción de Señal , Piel/inmunología , Piel/patología , Especificidad por Sustrato , Canales Catiónicos TRPC/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/inmunología
6.
Chest ; 98(4): 857-65, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2119951

RESUMEN

In the present study, we assessed the occurrence of respiratory muscle rest during long lasting INPV runs using a pneumowrap ventilator at different pressure levels. We measured two indices of diaphragmatic activity: transdiaphragmatic pressure and the electrical activity of the diaphragm. Five healthy volunteers and six COPD patients were studied during spontaneous breathing and during 30-minute runs of INPV at a pressure of -2, -15 and -30 cmH2O. Ventilation, rib cage and abdomen motion were measured by inductive plethysmography; Pdi was obtained as the difference between gastric and esophageal pressures; Edi was recorded with surface electrodes. About 10 minutes of INPV (adaptation phase) were needed to obtain stable values in all the variables recorded. Ventilation increased in both groups up to threefold by increasing the negative pressure applied, this being due to changes in tidal volume. Changes in Pga swings mainly accounted for the reduction in Pdi that became negative during the run at -30 cmH2O. In both groups, Edi, after adaptation, showed no change during INPV at -2 cmH2O but a progressive reduction from control, during INPV at -15 and -30 cmH2O. We conclude that INPV by a pneumowrap ventilator can induce partial respiratory muscle rest in normal subjects and COPD patients.


Asunto(s)
Diafragma/fisiopatología , Enfermedades Pulmonares Obstructivas/fisiopatología , Ventiladores de Presión Negativa , Adulto , Anciano , Dióxido de Carbono/sangre , Diafragma/fisiología , Electromiografía , Esófago/fisiología , Esófago/fisiopatología , Humanos , Enfermedades Pulmonares Obstructivas/sangre , Enfermedades Pulmonares Obstructivas/terapia , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Pletismografía , Presión , Respiración/fisiología , Estómago/fisiología , Estómago/fisiopatología
7.
J Appl Physiol (1985) ; 89(6): 2165-73, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11090563

RESUMEN

Diffusional permeability (P) to inulin (P(in)), albumin (P(alb)), and dextrans [70 (P(dx 70)), 150 (P(dx 150)), 550 (P(dx 550)), and 2, 000 (P(dx 2,000))] was determined in specimens of parietal pericardium of rabbits, which may be obtained with less damage than pleura. P(in), P(alb), P(dx 70), P(dx 150), P(dx 550), and P(dx 2, 000) were 0.51 +/- 0.06 (SE), 0.18 +/- 0.03, 0.097 +/- 0.021, 0. 047 +/- 0.011, 0.025 +/- 0.004, and 0.021 +/- 0.005 x 10(-5) cm/s, respectively. P(in), P(alb), and P(dx 70) of connective tissue, obtained after removal of mesothelium from specimens, were 10.3 +/- 1.42, 2.97 +/- 0.38, and 2.31 +/- 0.16 x 10(-5) cm/s, respectively. Hence, P(in), P(alb), and P(dx 70) of mesothelium were 0.54, 0.20, and 0.10 x 10(-5) cm/s, respectively. Inulin (like small solutes) fitted the relationship P-solute radius for restricted diffusion with a 6-nm "pore" radius, whereas macromolecules were much above it. Hence, macromolecule transfer mainly occurs through "large pores" and/or transcytosis. In line with this, the addition of phospholipids on the luminal side (which decreases pore radius to approximately 1.5 nm) halved P(in) but did not change P(alb) and P(dx 70). P(in) is roughly similar in mesothelium and capillary endothelium, whereas P to macromolecules is greater in mesothelium. The albumin diffusion coefficient through connective tissue was 17% of that in water. Mesothelium provides 92% of resistance to albumin diffusion through the pericardium.


Asunto(s)
Tejido Conectivo/metabolismo , Dextranos/farmacocinética , Inulina/farmacocinética , Pericardio/metabolismo , Fosfolípidos/farmacocinética , Albúmina Sérica Bovina/farmacocinética , Animales , Dextranos/química , Difusión , Epitelio/metabolismo , Sustancias Macromoleculares , Peso Molecular , Permeabilidad , Conejos
8.
J Appl Physiol (1985) ; 87(2): 538-44, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10444610

RESUMEN

Diffusional permeability (P) to water (P(w)), Cl(-) (P(Cl(-))), and mannitol (P(man)) was determined in specimens of rabbit parietal pericardium without and with phospholipids added on the luminal side, as previously done with sucrose and Na(+). P to the above-mentioned molecules and to Na(+) (P(Na(+))) was also determined after mesothelium was scraped away from specimens. P(w), P(Cl(-)), P(Na(+)), and P(man) of connective tissue were the following (x10(-5) cm/s): 73.1 +/- 7.3 (SE), 59.5 +/- 4.5, 41.7 +/- 3.4, and 23.4 +/- 2.4, respectively. From these and corresponding data on integer pericardium, P(w), P(Cl(-)), P(Na(+)), and P(man) of mesothelium were computed. They were the following: 206, 17.9, 9.52, and 3.93, and 90.2, 14.4, 4.34, and 1.75 x 10(-5) cm/s without and with phospholipids, respectively. As previously found for P to sucrose, P to solutes is smaller in mesothelium than in connective tissue, although the latter is approximately 35-fold thicker; instead, P(w) is higher in mesothelium, suggesting marked water diffusion through cell membrane. Equivalent radius of paracellular "pores" of mesothelium was computed with two approaches, disregarding P(w). The former, a graphical analysis on a P-molecular radius diagram, yielded 6.0 and 1.7 nm without and with phospholipids, respectively. The latter, on the basis of P(man), P to sucrose, and function for restricted diffusion, yielded 7.8 and 1. 1 nm, respectively.


Asunto(s)
Uniones Intercelulares/química , Pericardio/metabolismo , Animales , Cloruros/metabolismo , Tejido Conectivo/metabolismo , Difusión , Epitelio/metabolismo , Técnicas In Vitro , Manitol/metabolismo , Pericardio/citología , Permeabilidad , Fosfolípidos/farmacología , Conejos , Sodio/metabolismo , Sacarosa/metabolismo , Agua/metabolismo
9.
J Appl Physiol (1985) ; 65(3): 1286-95, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3182498

RESUMEN

We measured the changes in pleural surface pressure (delta Ppl) in the area of apposition of the rib cage to the diaphragm (Aap) in anesthetized dogs during spontaneous breathing, inspiratory efforts after airway occlusion at functional residual capacity, and phrenic stimulation. Intact dogs were in supine or lateral posture; partially eviscerated dogs were in lateral posture. delta Ppl,ap often differed significantly from changes in abdominal pressure (delta Pab); sometimes they differed in sign (except during phrenic stimulation). Changes in transdiaphragmatic pressure in Aap (delta Pdi,ap) could be positive or negative and were less in eviscerated than in intact dogs. delta Pdi,ap could differ in sign among respiratory maneuvers and over different parts of Aap. Hence average delta Pdi,ap should be closer to zero than delta Pdi,ap at a given site. Since delta Ppl,ap = delta Prc,ap, where Prc,ap represents rib cage pressure in Aap, delta Pdi,ap = delta Pab - delta Prc,ap. Hence, considering that delta Pab and delta Prc depend on different factors, delta Pdi,ap may differ from zero. This pressure difference seems related to the interaction between two semisolid structures (contracted diaphragm and rib cage in Aap) constrained to the same shape and position.


Asunto(s)
Pleura/fisiología , Músculos Respiratorios/fisiología , Animales , Diafragma/fisiología , Perros , Femenino , Masculino , Contracción Muscular , Presión , Respiración , Costillas
10.
J Appl Physiol (1985) ; 65(3): 1296-300, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3182499

RESUMEN

Changes in pleural surface pressure in area of apposition of diaphragm to rib cage (delta Ppl,ap), changes in abdominal pressure (delta Pab), and redial displacement of the 11th rib have been recorded in anesthetized, paralyzed dogs during lung inflation or deflation. Above functional residual capacity (FRC) changes in transdiaphragmatic pressure in area of apposition (delta Pdi,ap) were essentially nil in intact (INT) dogs either in lateral or supine posture, and in partially eviscerated (EVS) dogs in lateral posture, either in the 10th or 11th intercostal space. Below FRC delta Pdi,ap could be positive (INT lateral and EVS), nil (EVS), or negative (INT supine and EVS); it could be different in the 10th and 11th intercostal spaces. Hence, with stretched (like with contracted) diaphragm, delta Ppl,ap measured at one site often differs from delta Pab and is not representative of average pressure acting on area of apposition. With volume increase above FRC, the 11th rib moved slightly in and then out in EVS and linearly out in INT. With volume decrease below FRC it moved out progressively in EVS, and it moved in and eventually reversed in INT. In paralyzed dogs in lateral posture the factor having the greatest influence on displacement of the abdominal rib cage is Pab. Mechanical linkage with pulmonary rib cage becomes relevant at large volume, whereas insertional traction of diaphragm becomes relevant at low volume.


Asunto(s)
Diafragma/fisiopatología , Parálisis/fisiopatología , Animales , Perros , Femenino , Capacidad Residual Funcional , Masculino , Movimiento , Contracción Muscular , Presión , Respiración , Costillas/fisiopatología
11.
J Appl Physiol (1985) ; 85(2): 471-7, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9688722

RESUMEN

Diffusional permeability (P) to sucrose (Psuc) and Na+ (PNa+) was determined in specimens of rabbit sternal parietal pericardium, which may be obtained without stripping. Specimens were mounted in an Ussing apparatus with 3H-labeled sucrose and 22Na+ in a luminal (L) or interstitial (I) chamber. Psuc was 2.16 +/- 0.44 for L-->I and 2.63 +/- 0.45 (SE) x 10(-5) cm/s for I-->L, i.e., approximately 10 times smaller than that previously obtained in stripped specimens of pleura despite the similarity of intercellular junctions in pericardium and pleural mesothelium of various species. These findings suggest that previous Psuc was overestimated because stripping damages the mesothelium. PNa+ (x10(-5) cm/s) was 7.07 +/- 0.71 for L-->I and 7.37 +/- 0.69 x 10(-5) cm/s for I-->L. Measurements were also done with phospholipids, which are adsorbed on the luminal side of mesothelium in vivo. With phospholipids in L, Psuc was 0.75 +/- 0.10 and 0.65 +/- 0.08 and PNa+ was 3.80 +/- 0.32 and 3.76 +/- 0.15 x 10(-5) cm/s for L-->I and I-->L, respectively, i. e., smaller than without phospholipids. With phospholipids in I (where they are not adsorbed), Psuc (2.33 +/- 0.42 x 10(-5) cm/s) and PNa+ (7.01 +/- 0.45 x 10(-5) cm/s) were similar to those values without phospholipids. Hence, adsorbed phospholipids decrease P of mesothelium. If the mesothelium were scraped away from the specimen, Psuc of the connective tissue would be 13.2 +/- 0.76 x 10(-5) cm/s. Psuc of the mesothelium, computed from Psuc of the unscraped and scraped specimens, corrected for the effect of unstirred layers (2. 54 and 19.4 x 10(-5) cm/s, respectively), was 2.92 and 0.74 x 10(-5) cm/s without and with phospholipids, respectively. Hence, most of the resistance to diffusion of the pericardium is provided by the mesothelium.


Asunto(s)
Pericardio/metabolismo , Animales , Tejido Conectivo/metabolismo , Difusión , Epitelio/anatomía & histología , Epitelio/metabolismo , Femenino , Técnicas In Vitro , Pericardio/anatomía & histología , Permeabilidad , Fosfolípidos/metabolismo , Conejos , Sodio/metabolismo , Radioisótopos de Sodio , Soluciones
12.
J Appl Physiol (1985) ; 62(4): 1655-64, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3597237

RESUMEN

We tested the hypothesis that the mechanical arrangement of costal (COS) and crural (CRU) diaphragms can be changed from parallel to series when direct or indirect transmission of tension occurs. Ratio of rib cage to abdominal displacement (RC/AB) resulting from separate COS and CRU stimulations were used to measure RC expanding action. Hyperinflation in six dogs caused RC/AB with COS and CRU stimulations to change progressively from 0.53 +/- 0.07 (SE) and 0.03 +/- 0.05 at functional residual capacity (FRC) to -0.48 +/- 0.08 and -0.46 +/- 0.05 at 68% inspiratory capacity, respectively. Liquid substitution of abdominal contents in six other dogs equalized abdominal pressure swings (delta Pab), without changing chest wall elastic properties or geometry, or costal RC/AB (0.35 +/- 0.07 before and 0.33 +/- 0.06 after) but caused crural RC/AB to change from 0.01 +/- 0.05 to 0.31 +/- 0.01. We conclude that hyperinflation changes fiber orientation, allowing direct transmission of tension between COS and CRU, which become linked mechanically in series (the diaphragm acts as a unit with RC deflating action); and equalization of delta Pab causes indirect transmission of tension between COS and CRU, which become linked in series (the diaphragm acts as a unit with RC inflating action).


Asunto(s)
Abdomen/fisiología , Diafragma/fisiología , Respiración , Animales , Perros , Modelos Biológicos , Movimiento , Presión , Costillas/fisiología
13.
J Appl Physiol (1985) ; 68(5): 2075-82, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2361909

RESUMEN

The pattern of rib cage (RC) and abdomen (AB) motion and the electromyograms of the triangularis sterni (TS) and abdominal external oblique (EO) muscles were studied during speech and reading in six normal uninformed subjects in the sitting posture. Most phrases were started from within the tidal breathing range and extended below RC and AB spontaneous end-expiratory volumes. On the average, 75% of the change in chest wall volume occurred below the resting end-expiratory level. The expired volume resulted from a large predominance of RC displacement, and this was accompanied by marked recruitment of the TS. The EO was also generally activated, but the pattern of activation was less consistent. We conclude that 1) speech occurs primarily below the spontaneous end-expiratory level; 2) most of the volume change is caused by active emptying of the RC produced, at least in part, by contraction of the TS; 3) concomitant activation of the abdominal muscles serves to optimize the inspiratory function of the diaphragm, which has to contract rapidly between phrases to refill the respiratory system.


Asunto(s)
Fonación/fisiología , Músculos Respiratorios/fisiología , Tórax/fisiología , Voz/fisiología , Adulto , Electromiografía , Humanos , Mediciones del Volumen Pulmonar , Masculino , Movimiento , Mecánica Respiratoria/fisiología
14.
J Appl Physiol (1985) ; 66(5): 2061-70, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2745275

RESUMEN

Five mongrel dogs (2 interstitial and 3 alveolar edema) were studied. Lung mechanics were measured by recording the flow, volume, and esophageal pressure according to the standard technique. Edema was produced by infusion of Ringer lactate solution. Lung sounds were recorded on tape from the dependent part of the chest wall. Lung sound signals were high-pass filtered at 100 Hz and subjected to fast Fourier transform. Samples of lung sounds were analyzed before (control) and at 5, 10, 20, 30, and 40 min after the infusion. The mean, median, and mode frequencies of sound power spectra at the control time were, respectively, 169.6 +/- 29.19, 129.6 +/- 29.81, and 136.0 +/- 29.87 (SD) Hz. These values increased significantly at 5 min after infusion to 194.0 +/- 26.08 (P less than 0.0037), 150.2 +/- 23.48 (P less than 0.0085), and 164.6 +/- 28.74 Hz (P less than 0.02), respectively. These values stayed significantly elevated at 10, 20, 30, and 40 min. The pulmonary wedge pressure, lung dynamic compliance, and pulmonary resistance were measured also at the same times. The mean, median, and mode frequencies correlated with pulmonary wedge pressure (P less than 0.00001, P less than 0.0001, P less than 0.0001), lung dynamic compliance (P less than 0.001, P less than 0.0001, P less than 0.0001), and pulmonary resistance (P less than 0.00001, P less than 0.00001, P less than 0.0001), respectively. There were no significant adventitious sounds up to 40 and 50 min after infusion. We concluded that pulmonary congestion and early edema alter the frequency characteristics of lung sounds early, before the occurrence of adventitious sounds. These altered lung sounds may be used as an index of pulmonary congestion and impending edema.


Asunto(s)
Pulmón/fisiopatología , Edema Pulmonar/diagnóstico , Ruidos Respiratorios , Animales , Modelos Animales de Enfermedad , Perros , Femenino , Masculino , Edema Pulmonar/fisiopatología , Valores de Referencia , Respiración , Volumen de Ventilación Pulmonar , Capacidad Vital
15.
J Appl Physiol (1985) ; 58(6): 1849-58, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4008405

RESUMEN

In 11 mechanically ventilated patients, respiratory mechanics were measured 1) during constant flow inflation and 2) following end-inflation airway occlusion, as proposed in model analysis (J. Appl. Physiol. 58: 1840-1848, 1985. During the latter part of inflation, the relationship between driving pressure and lung volume change was linear, allowing determination of static respiratory elastance (Ers) and resistance (RT). The latter represents in each patient the maximum resistance value that can obtain with the prevailing time constant inhomogeneity. Following occlusion, Ers and RT were also obtained along with RT (min) which represents a minimum, i.e., resistance value that would obtain in the absence of time constant inhomogeneity. A discrepancy between inflation and occlusion Ers and RT was found only in the three patients without positive end-expiratory pressure, and could be attributed to recruitment of lung units during inflation. In all instances Ers and RT were higher than normal. RT(min) was lower in all patients than the corresponding values of RT, indicating that resistance was frequency dependent due to time constant inequalities. Changes in inflation rate did not affect Ers, while RT increased with increasing flow.


Asunto(s)
Pulmón/fisiopatología , Respiración Artificial , Respiración , Insuficiencia Respiratoria/fisiopatología , Adulto , Anciano , Resistencia de las Vías Respiratorias , Femenino , Humanos , Rendimiento Pulmonar , Mediciones del Volumen Pulmonar , Masculino , Persona de Mediana Edad , Ventilación Pulmonar , Insuficiencia Respiratoria/terapia
16.
J Appl Physiol (1985) ; 62(1): 108-15, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3104281

RESUMEN

We compared areas and diameters of small airways and arteries in three groups of anesthetized dogs: 1) control (n = 5), 2) hydrostatic edema induced by fluid overload (n = 13), and 3) increased permeability edema induced with alpha-naphthylthiourea (n = 5). We measured pulmonary arterial and wedge pressures in all groups and cardiac output in the hydrostatic edema group. Postmortem, lobes were frozen at functional residual capacity and samples taken for measurements of extravascular lung water (Qwl/dQl) and for light microscopy. We also examined lobes from hydrostatic edema experiments fixed at transpulmonary pressures of 5 and 27 cmH2O. From the histology slides, bronchovascular bundles with respiratory bronchioles (n = 706) and bronchioles (n = 467) were photographed and airway and vessel areas and diameters measured. Alveolar and airway luminal edema were graded. We found that only in hydrostatic edema, pulmonary arterial and wedge pressures increased and vascular resistance fell with fluid infusion. Mean Qwl/dQl values were 3.80 +/- 0.17, 6.81 +/- 0.96, and 9.34 +/- 0.62 (SE) in control, hydrostatic, and increased permeability edema groups, respectively. By quantitative histology, airway and arterial areas and diameters did not decrease in edema and rose with increasing transpulmonary pressure. Variable quantities of air-space edema were seen. We conclude that interstitial edema does not compress small airways or arteries and that other mechanisms, including alveolar and airway luminal edema, may explain reported increases in airway resistance.


Asunto(s)
Pulmón/patología , Arteria Pulmonar/patología , Edema Pulmonar/patología , Animales , Gasto Cardíaco , Perros , Femenino , Hemodinámica , Soluciones Isotónicas , Pulmón/irrigación sanguínea , Masculino , Edema Pulmonar/etiología , Presión Esfenoidal Pulmonar , Lactato de Ringer , Tiourea/análogos & derivados , Resistencia Vascular
17.
J Appl Physiol (1985) ; 59(2): 647-52, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4030618

RESUMEN

Flow (V), volume (V), and tracheal pressure (Ptr) were measured throughout a series of brief (100 ms) interruptions of expiratory V in six patients during anesthesia (halothane-N2O) and anesthesia-paralysis (succinylcholine). For the latter part of spontaneous expiration and throughout passive deflation during muscle paralysis, a plateau in postinterruption Ptr was observed, indicating respiratory muscle relaxation. Under these conditions, passive elastance of the total respiratory system (Ers) was determined as the plateau in postinterruption Ptr divided by the corresponding V. The pressure-flow relationship of the total system was determined by plotting the plateau in Ptr during interruption against the immediately preceding V. Ers averaged 23.5 +/- 1.9 (SD) cmH2O X l-1 during anesthesia and 25.5 +/- 5.4 cmH2O X l-1 during anesthesia-paralysis. Corresponding values of total respiratory system resistance were 2.0 +/- 0.8 and 1.9 +/- 0.6 cmH2O X l-1 X s, respectively. Respiratory mechanics determined during anesthesia paralysis using the single-breath method (W.A. Zin, L. D. Pengelly, and J. Milic-Emili, J. Appl. Physiol. 52: 1266-1271, 1982) were also similar. Early in spontaneous expiration, however, Ptr increased progressively during the period of interruption, reflecting the presence of gradually decreasing antagonistic (postinspiratory) pressure of the inspiratory muscles. In conclusion, the interrupter technique allows for simultaneous determination of the passive elastic as well as flow-resistive properties of the total respiratory system. The presence of a plateau in postinterruption Ptr may be employed as a useful and simple criterion to confirm the presence of respiratory muscle relaxation.


Asunto(s)
Anestesia , Pruebas de Función Respiratoria , Adulto , Presión Atmosférica , Femenino , Humanos , Rendimiento Pulmonar , Mediciones del Volumen Pulmonar , Masculino , Parálisis/fisiopatología , Ventilación Pulmonar , Tráquea/fisiología
18.
Clin Chest Med ; 19(2): 241-60, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9646979

RESUMEN

The pleural space provides the mechanical coupling between lung and chest wall: two views about this coupling are reported and discussed. Information on volume, composition, thickness, and pressure of the pleural liquid under physiologic conditions in a few species is provided. The Starling pressures of the parietal pleura filtering liquid into pleural space, and those of the visceral pleura absorbing liquid from the space are considered along with the permeability of the mesothelium. Information on the lymphatic drainage through the parietal pleura and on the solute-coupled liquid absorption from the pleural space under physiologic conditions and with various kinds of hydrothorax are provided.


Asunto(s)
Permeabilidad de la Membrana Celular/fisiología , Pleura/fisiopatología , Equilibrio Hidroelectrolítico/fisiología , Factores de Edad , Animales , Epitelio/fisiopatología , Humanos , Hidrotórax/fisiopatología , Sistema Linfático/fisiopatología , Especificidad de la Especie
20.
G Chir ; 12(4): 261-4, 1991 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-1911075

RESUMEN

Primary lymphoma of the lung is a rare pathological condition arising from mucosa-associated lymphoid tissue (MALT). The lack of specific symptoms and the related diagnostic problems induced the authors to report a clinical case recently observed. Therefore, some histopathologic characteristics useful for a correct differential diagnosis with the pseudolymphoma of the lung and the interstitial lymphocyte pneumonia are analysed.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/diagnóstico , Neoplasias Pulmonares/diagnóstico , Anciano , Diagnóstico Diferencial , Humanos , Leucemia Linfocítica Crónica de Células B/patología , Leucemia Linfocítica Crónica de Células B/cirugía , Pulmón/patología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Masculino , Neumonectomía
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