Search PubMed⌕ Search

Biomedical subjects

F Marchal

Publications and source records attributed to F Marchal.

At least 73 records · Page 4Linked to original sources
PubMed1998

[Medial pancreatectomy with pancreatogastric anastomosis in pancreatic neoplasms].

AIM OF THE STUDY: To report a personal series of ten patients who underwent a medial pancreatectomy with pancreaticogastrostomy for tumor of the pancreas. MATERIAL AND METHODS: An equal number of five patients had solid and cystic tumors. The solid tumors were all endocrine and included two cases of insulinoma and solitary cases of VIPoma, glucagonoma, and non-secreting tumor. Five patients had a cystic tumor which was in two cases a serous cystadenoma, and in the other cases, a mucinous cystadenoma, a solid pseudopapillary tumor, and a solitary hydatid cyst of the pancreas. The operative procedure included a middle segment pancreatectomy, a suture of the proximal pancreatic stump, an anastomosis of the distal pancreatic stump with the stomach and an external transgastric drainage of the distal main pancreatic duct. RESULTS: In the postoperative course, a sero-hematic collection close to the anastomosis occurred in four patients and required external drainage in three cases. All patients recovered without sequela of pancreatic dysfunction. CONCLUSION: This series confirms the place of medial pancreatectomy in resection of non-enucleable tumors of the middle part of the pancreas. It also shows that pancreaticogastrostomy is a technical simplification compared to Roux-en Y pancreaticojejunostomy in this particular modality of pancreatectomy.

Adolescent↗
PubMed1998

[Respiratory evolution of patient with mucoviscidosis treated with mucolytic agents plus dornase alfa].

AIM: Modifications of bronchial secretions in cystic fibrosis patients account for the long-lasting use of mucolytic agents, despite the lack of adequately controlled clinical studies supporting this approach. Hyperviscosity of bronchial secretions mainly depend on their high DNA content, as a result of degradation of polymorphonuclear neutrophils mobilized by infection and inflammation. This phenomenon has led to the treatment of respiratory complications with human recombinant deoxyribonuclease (dornase alfa). In the present study, we compared the clinical and respiratory outcome in patients receiving mucolytic agents followed by dornase alfa, each for 1 year. POPULATION AND METHODS: Fifty-four patients, aged 5 years or more, have been prospectively followed for 2 years. They received first a 12-month association of mesna (two nebulisations per day) and oral ambroxol (60 mg per day, divided in two doses), followed by a 12-month treatment with one daily aerosol of dornase alfa only (2.5 mg per day). The primary end-points were the results of pulmonary function tests. Secondary end-points were subjective symptoms, bacterial colonization, consumption of antibiotics, and clinical tolerance. RESULTS: At the end of the 12-month mucolytic therapy, a significant decrease of forced expiratory volume/second (FEV1, -10.5% as compared to baseline values) and forced vital capacity (FVC, -12.8%) was observed. At the end of 12-month dornase alfa, FEV1 and FVC had increased by 7.7 and 5.3%, respectively. This change was statistically significant only for FEV1 in most severely disabled patients. However, forced expiratory flow 25-75% (FEF 25-75) decreased during the 2 year period of observation, by 5.6% the first year and 4.9% the second year. The mean number of days with parenteral antibiotics did not statistically differ between both treatments, except for patients more than 15 years of age. In this subgroup, the mean number decreased from 40 days in the first year to 27 in the second year (P < 0.05). Acceptability of treatment by the patients themselves was better with dornase alfa than with mucolytic therapy. However, several episodes of hemoptysis, frequent in only one case, were associated with the treatment by dornase alfa. CONCLUSION: Dornase alfa was associated with a stabilisation, and even a trend to improvement in pulmonary function tests. This stabilisation is by itself a very encouraging result. Long-term comparative studies are needed to evaluate the benefits of dornase alfa in the treatment of respiratory complications of cystic fibrosis and specify the optimal modalities of its use. Synergistic combinations with mucolytic therapy and/or anti-inflammatory drugs could be viewed as a future prospect.

Adolescent↗
PubMed1998

Virus burden in lymph nodes and blood of subjects with primary human immunodeficiency virus type 1 infection on bitherapy.

At present, it is not known whether undetectable plasma viremia corresponds to an absence of human immunodeficiency virus type 1 (HIV-1) replication in lymphoid tissues. This issue has been explored in 11 subjects with primary HIV-1 infection treated with zidovudine plus didanosine by evaluating virologic markers in blood and lymphoid tissues 9-18 months after initiation of treatment. These markers include plasma viremia, measured with a sensitive assay with a detection limit of 20 HIV-1 RNA copies/mL, infectious virus titers and proviral DNA in lymph node mononuclear cells, and HIV-1 RNA in lymphoid tissue. Five subjects had plasma viremia <20 copies/mL and showed no evidence of viral replication in lymphoid tissue. Six subjects had both detectable plasma viremia and evidence of HIV-1 RNA in lymphoid tissue. The results indicate that absence of detectable HIV RNA in lymphoid tissue is associated with viremia levels of HIV-1 RNA <20 copies/mL.

Adenoids↗
PubMed1998

Mechanisms of ventilatory inhibition by exogenous dopamine in cats.

Intravenous injection of dopamine (DA) has consistently been shown to depress minute ventilation (VE). Whereas at low dosage (</=10 microgram/kg) this effect may be accounted for by inhibition of the carotid sinus nerve chemosensory discharge (CSNCD), other mechanisms appear to be involved with large dosage (>/=50 microgram/kg). The purpose of this study was to elucidate the mechanisms of DA-induced VE depression. The effects of intravenous injection of DA doses ranging from 1 to 200 microgram/kg were studied in 18 anesthetized cats. DA was injected during air and O2 breathing, after alpha-adrenergic blockade by phenoxybenzamine and after baro- and chemodenervation. VE and CSNCD were also simultaneously recorded on four occasions. In contrast to that with use of low-dose DA, VE depression induced by high-dose DA was dissociated from CSNCD, persisted during 100% O2 breathing, and was significantly correlated with the rise in arterial blood pressure. Although blunted, VE depression was still present after complete chemo- and barodenervation but was suppressed by blocking of the concomitant vasoconstriction with phenoxybenzamine. It is concluded that reflexes of circulatory origin contribute to the VE depression induced by large-dose DA, in addition to its effects on arterial chemoreceptors. The contribution of baroreceptor stimulation and peripheral vasoconstriction is discussed.

Action Potentials↗
PubMed1998

[The role of percutaneous drainage in acute calculous cholecystitis. Apropos of 27 cases].

Surgery is the treatment of acute calculous cholecystitis. Mortality and morbidity are considerable for patients with anesthetic risk factors. In this context, ultrasound-guided percutaneous drainage seems to be a alternative to urgent surgery. The place of this technic and its results have not been determined with certainty. We report our experience of percutaneous drainage in acute calculous cholecystitis, based on a series of 27 patients treated between May 1992 and May 1996. A favorable course was observed after drainage in 26 patients, one patient was operated urgently for purulent peritonitis on D1. One drain migrated into the gallbladder and required cholecystenterostomy en D30. Seventeen patients underwent cholecystectomy after the acute episode. Surgery was contra-indicated in light patients: two presented recurrence of acute calculous cholecystitis and six remained asymptomatic. The aim of this study was to define the place of this technic in the treatment of acute calculous cholecystitis, and estimate the results in terms of mortality, morbidity and recurrence.

Acute Disease↗
PubMed1997

Feasibility and outcome of a progressively accelerated concomitant boost radiotherapy schedule for head and neck carcinomas.

PURPOSE: To evaluate toxicity and treatment outcome in patients with head and neck carcinomas treated with a modified bifractionated concomitant boost radiotherapy schedule. METHODS AND MATERIALS: Eighty-five patients were treated from February 1991 to October 1995. According to clinical TN stage 23 tumors were T1, 33 T2, 20 T3, 9 T4, 44 N0, and 41 N1-N3. The primary tumor was located in the oral cavity in 6 patients, oropharynx in 36, larynx in 19, hypopharynx in 17, and nasopharynx in 7. The basic treatment delivered 50.4 Gy in 28 fractions, once a day, to the primary site and both sides of the neck. During the last 3.5 weeks, a boost to the initial gross disease was delivered in 13 fractions of 1.5 Gy each as a second daily fraction in a progressively accelerated schedule (total dose 69.9 Gy). Eighteen patients had a uni- or bilateral neck dissection, and 2 an adenectomy before radiotherapy. The median follow-up for the surviving patients was 28 months (range: 3-61 months). RESULTS: All the patients completed the planned radiotherapy schedule. According to the RTOG scoring system, 57 patients (67%) presented with Grade 3-4 acute toxicity. Grade 3 dysphagia was observed in 20 patients (23.5%). Three patients died during the 3 months following the treatment. Among 73 patients evaluable for late effects, five developed Grade 3-4 complications. At 3 years actuarial loco-regional control was 67% and overall survival was 62%. CONCLUSIONS: Although longer follow-up is needed to evaluate the definitive results, we conclude that this particular concomitant boost schedule is feasible and appears to be effective. While acute toxicity was greater than in monofractionated schedules, it was manageable, provided that supportive care measures were implemented in a timely fashion.

Adult↗
PubMed1997

Ventilatory and gas exchange response during walking in severe peripheral vascular disease.

It has long been recognized that at the onset of a dynamic muscular exercise the ventilatory and the circulatory (blood flow) responses appear to be matched, thereby maintaining arterial blood gas homeostasis. Such a coupling has recently been suggested to rely upon ventilatory reflex triggered by mechanoreceptors encoding changes in muscle blood flow or, more likely, blood volume. The aim of this study was to investigate whether patients with severe peripheral blood flow limitation to the lower extremities have a normal ventilatory response during a light intensity exercise. The ventilatory and gas exchange temporal response characteristics were studied during a 6 min walking test in seven patients with severe ischemic peripheral vascular disease and in six normal age-matched subjects. The magnitude of the overall ventilatory and Vo2 increment at the end of the tests was similar in both groups. However, in contrast to the control subjects, who presented an almost rectangular response, the patients had a considerably slowed response dynamics (t50 = 33 +/- 4 vs. 9 +/- 3 sec for Vo2 and 37 +/- 5 vs. 10 +/- 8 sec for VE) with a dramatic reduction in the magnitude of the initial 20 sec of the responses. Although the slow Vo2 dynamics in patients presumably reflected the impeded perfusion of the working muscles. the accompanying sluggishness of the V1 course implies that either muscular ischemia actually inhibits ventilatory response to exercise or, more likely, that this response is strongly linked to the magnitude of the hyperemia in the exercising muscles.

Heart Rate↗
PubMed1997

Carotid body dopamine content and release by short-term hypoxia: effect of haloperidol and alpha methyl paratyrosine.

Dopamine (DA) is thought to modulate the transduction of the hypoxic stimulus by the glomus cell in the carotid body (CB). The hypothesis tested here is that presynaptic DA D2 receptors (D2's) located on the type 1 cell function as autoreceptors to control DA release and/or synthesis. The aim of the study was to compare the effects of blocking D2's with haloperidol and DA synthesis with alpha methyl paratyrosine (AMPT) on the in vitro carotid body DA response to hypoxia. 54 CB's sampled from adult rabbits were incubated for one hour in a surviving medium bubbled with either 100% O2 or 8% O2 Sixteen CB's served as control (100% O2: n = 8, 8% O2: n = 8), 18 (100% O2: n = 8, 8% O2: n = 10) were sampled from rabbits pretreated with AMPT and 20 (100% O2: n = 12, 8% O2: n = 8) were incubated with micromolar concentrations of haloperidol. At the end of exposure. DA contained in the carotid body (DACB) and released in the surviving medium (DAr) were measured by HPLC. In 100% O2 DACB was not different between either AMPT or haloperidol and control, but DAr was significantly higher in the haloperidol group compared with control (mean +/- SE: 26.6 +/- 7.4 versus 7.6 +/- 2.0 pmol/h, P < 0.02). In 8% O2, control DACB (576 +/- 133 pmol/CB) was significantly higher than AMPT or haloperidol (respectively 228 +/- 29.6 and 246 +/- 49.9 pmol/CB, P < 0.01) and control DAr (234 +/- 72.3 pmol/h) was also significantly higher than AMPT or haloperidol (respectively 28.8 +/- 5.2 and 40.6 +/- 11.4 pmol/h, P < 0.01). Finally, DAr was significantly larger in 8% O2 than in 100% O2 in control and AMPT groups (P < 0.01), but not in the haloperidol group. The increase in DAr by haloperidol in the resting CB is consistent with the blockade of D2's regulating DA release. The decreased DAr in 8% O2 after AMPT suggests that increased DA synthesis contributes to maintain DA secretion by the type I cell exposed to short term hypoxia. The lack of difference in DAr between 8% O2 and 100% O2 after haloperidol probably reflects non specific--i.e., D2 independent--effect of micromolar concentration of haloperidol on DA synthesis and/or sodium-calcium exchangers during hypoxia.

Analysis of Variance↗
PubMed1997

Familial transmission of a serious disease--producing group A streptococcus clone: case reports and review.

Invasive group A streptococcus (GAS) infections are emerging diseases; however, person-to-person transmission of invasive GAS producing life-threatening infection has been observed rarely. We report a small intrafamilial cluster of life-threatening GAS infections. A previously healthy 47-year-old father developed necrotizing fasciitis of the neck. Two days later, his 16-year-old daughter developed streptococcal angina, pneumonia, and pleural empyema. Both patients had signs of streptococcal toxic shock syndrome. Pulsed field gel electrophoresis revealed that the M6 strains of GAS isolated from the father and daughter had identical patterns. Cases of person-to-person transmission of invasive GAS infection reported in the literature are also reviewed.

Adolescent↗
PubMed1997

Necrotizing fasciitis of the head and neck: role of CT in diagnosis and management.

PURPOSE: To determine the characteristic diagnostic features of necrotizing fasciitis and to evaluate the role of computed tomography (CT) in its management. MATERIALS AND METHODS: Fourteen patients with surgically proved necrotizing fasciitis of the extracranial head and neck were examined with contrast material-enhanced CT. Clinical, radiologic, surgical, pathologic, and anatomic findings at admission and after initial treatment were analyzed retrospectively. RESULTS: Constant CT features of necrotizing fasciitis were diffuse thickening and infiltration of the cutis and subcutis (cellulitis); diffuse enhancement and/or thickening of the superficial and deep cervical fasciae (fasciitis); enhancement and thickening of the platysma, sternocleidomastoid muscle, or strap muscles (myositis); and fluid collections in multiple neck compartments. Inconstant CT features included gas collections, mediastinitis, and pleural or pericardial effusions. All patients underwent extensive surgical debridement. Follow-up CT scans in 11 patients revealed clinically unsuspected progression of the inflammatory process in previously unaffected areas, a finding that warranted additional surgery in nine patients. Twelve patients survived, and two patients died of septic shock and aspiration pneumonia despite intensive surgical and medical treatment. CONCLUSION: Early recognition of necrotizing fasciitis with CT enables appropriate surgical treatment. CT may also be a useful guide in further patient treatment after initial surgical debridement.

Adolescent↗
PubMed1997

Laryngeal reflex apnea is blunted during and after hindlimb muscle contraction in sheep.

This study was carried out on seven chloralose-anesthetized sheep and was designed to investigate the role of muscular afferent fiber stimulation on the duration of reflex apnea triggered by laryngeal stimulation (LS). In six animals, injection of distilled water onto the laryngeal mucosa provoked a 15.7 +/- 1.0 s (mean +/- SE) apnea associated with a rise in systemic blood pressure (+7 +/- 0.8 Torr). Electrically induced contractions (EIC) of the hindlimb muscles doubled the metabolic rate and ventilation and reduced the duration of the apnea produced by LS to 7.4 +/- 1.0 s (P < 0.01). Apnea duration was still reduced during the first minute after the cessation of EIC (7.2 +/- 1.1 s, P < 0.01) but returned to control after a 5-min recovery period (16.7 +/- 1.6 s). The apnea triggered by LS was also reduced during EIC when the venous return was impeded by occluding the inferior vena cava (5.2 +/- 1.1 s, P < 0.01), despite a profound hypocapnia (20.7 +/- 0.3 Torr). The duration of apnea was not significantly affected (14.2 +/- 1.4 s) by breathing a 6% CO2-14% O2 in N2 gas mixture that roughly mimicked the alveolar gas composition when the apnea turned off. These results suggest that chemical drive has a negligible role in the fast reinitiation of breathing after LS during muscular stimulation. Stimulation of muscle afferent fibers does, however, appear to be a potent source of ventilatory reflexes capable of counteracting the inhibition of breathing resulting from laryngeal stimulation. Conversely, it is postulated that any reduction in somatic afferent traffic during this type of reflex apnea, including that resulting from the LS-induced systemic vasoconstriction, may delay the termination of apnea.

Animals↗
PubMed1997

Effects of caffeine on carotid sinus nerve chemosensory discharge in kittens and cats.

Caffeine (C) decreases apneic episodes in premature infants and is thought to stimulate breathing mainly by a central mechanism. While the methylxanthines theophylline and aminophylline are known to alter the carotid chemoreceptor activity, there are little data on C. The aim of the study was to examine the effects of C on the carotid sinus nerve discharge (CSND) in developing animals. Nine kittens 17-21 days old and six adult cats that were anesthetized and artificially ventilated were studied. They received four consecutive doses of C, each of 10 mg/kg, administered at intervals of 20 min either as intravenous bolus injection (6 kittens, 3 cats) or continuous infusion (3 kittens, 3 cats). Bolus injections of C invariably induced a prompt but transient increase in the CSND from 4.1 +/- 0.6 to 8.1 +/- 1.0 (SE) impulses/s in kittens (P = 0.01) and form 3.9 +/- 0.1 to 7.9 to 1.0 impulses/s in cats (after the first injection). This response was associated with a significant decrease in arterial blood pressure. Continuous infusion of C did not induce any early change in either CSND or blood pressure in kittens or cats. Fifteen minutes after C injection or infusion was begun, CSND values in air, 8% O2-balance N2, or 100% O2 were not significantly different from control. Haloperidol administered at the end of the experiment in four cats and four kittens significantly increased CSND and did not suppress the early response to C injection. It is concluded that caffeine administered by bolus in the kitten induces a transient stimulation of the CSND that is associated with a decrease in the arterial blood pressure and is independent of the dopaminergic mechanisms in the carotid body. The lack of sustained effect implies the main mechanism to the ventilatory stimulation by C must be central.

Animals↗
PubMed1996

Respiratory system reactance as an indicator of the intrathoracic airway response to methacholine in children.

The upper airways may contribute to increases in airway resistance in response to a bronchial challenge, and thus decrease the specificity of such challenge tests to diagnose airway hyperresponsiveness when forced oscillation techniques are used to evaluate changes in respiratory system resistance (Rrs). A concomitent decrease in respiratory system reactance (Xrs) may indicate a change in the intrathoracic airways and/or lung parenchyma, provided that extrathoracic airway wall motion is prevented. To test the value of Xrs in the evaluation of bronchial hyperresponsiveness, we studied the respiratory impedance response to methacholine in 38 children with a history of asthma (aged 6-14.5 years), and compared the results to changes in the forced expiratory volume in one second (FEV1). Rrs and Xrs were measured by the forced oscillation technique with pseudorandom (11 subjects) or sinusoidal (27 subjects) pressure variations applied around the child's head to minimize upper airway wall motion. Changes in Rrs and in Xrs at 12 Hz (Rrs12, Xrs 12) correlated significantly with changes in FEV1 (P < 0.005). A decrease in FEV1 > or = 20% was observed in 23 subjects. When these 23 subjects were compared with the 15 children who did not show significant changes in FEV1, the responding group had larger mean +/- SEM changes in Rrs (116.0 +/- 13.2% vs 60.4 +/- 11.4%, P < 0.006) and in Xrs (-2.1 +/- 0.4 hPa.s/L vs -0.9 +/- 0.3 hPa.s/L, P < 0.03) than the nonresponders. The receiver operating characteristics (ROC) curve analysis was used to assess the diagnostic value, i.e., specificity and sensitivity, of different levels of change in Rrs and Xrs, with reference to FEV1. The overall incidence of false results was similar for Rrs and Xrs. The optimum diagnostic value for Rrs was a 70% increase, which corresponded to a sensitivity of 87% and a specificity of 67%. For Xrs the optimum decision level was -1 hPa.s/L, corresponding to a sensitivity of 70% and a specificity of 80%. It is concluded that Xrs may improve the specificity of the forced oscillation technique in interpreting the airway response to methacholine. This may be of particular interest in young children unable to perform forced expirations.

Adolescent↗
PubMed1996

Papaverine injection into the hindlimb circulation stimulates ventilation in sheep.

To test the hypothesis, previously suggested by Huszczuk et al. (1993), that distention of the peripheral microvascular network could, per se, stimulate ventilation, the ventilatory effects of papaverine-induced muscular vasodilation were studied in ten anaesthetized sheep. Because systemic action of papaverine may involve the arterial baro- and chemoreceptors, the animals were surgically prepared for a reversible isolation of the hindlimb circulation. Papaverine injection (1-2 mg/kg) into the arterial inflow of the isolated limbs provoked a 13 +/- 6 sec-delayed increase in VE by 1.8 +/- 0.2 L min-1 (p < 0.01) with a concomitant decrease in peripheral vascular resistance and no decrease in the systemic arterial blood pressure. Identical control injection into a jugular vein prior to the hindlimb circulatory separation yielded an increase of VE by 4.95 +/- 0.58 L min-1 with a latency of 21 +/- 2 sec and a coinciding moderate decrease of the systemic arterial pressure. The present data suggest that papaverine injection into the hindlimb circulation can stimulate ventilation independently of its possible effects on the arterial baro- or chemoreceptors, supporting the hypothesis that muscular vasodilation could contribute to the control of breathing through a neural link.

Animals↗
PubMed1996

Effects of hypoxia on carotid body dopamine content and release in developing rabbits.

Hypoxia induces dopamine (DA) release from the carotid body (CB), but the role of DA during hypoxia in the postnatal maturation of carotid chemosensory discharge remains controversial. The aim of this study was to evaluate changes in CB content and release of DA evoked by hypoxia at different stages of development in the rabbit. Five groups of rabbits aged < or = 24 h (n = 9), 5 days (n = 27), 15 days (n = 18), 25 days (n = 16), and > or = 1 yr (n = 11) were studied. CBs were surgically removed and immediately incubated at 37 degrees C for 1 h in a surviving medium equilibrated with 100% O2 or 8% O2 in N2. The content of DA in the CB ([DA]CB) and the DA released in the surviving medium ([DA]r) were measured by high-performance liquid chromatography. [DA]CB was significantly larger in adults than in all pup groups in both 100% O2 [385.5 +/- 74.1 (SE) pmol/CB in adults and 43.6 +/- 6.0 pmol/CB in pups; P < 0.01] and hypoxia (518.1 +/- 99.9 pmol/CB in adults and 24.7 +/- 3.2 pmol/CB in pups; P < 0.01), presumably because of the larger CB mass. [DA]r was significantly larger in hypoxia than in 100% O2 only in 25-day-old rabbits (19.8 +/- 4.2 and 3.6 +/- 1.1 pmol/h, respectively; P < 0.01) and in adults (183.9 +/- 57.7 and 7.9 +/- 1.7 pmol/h, respectively; P < 0.01). The average ratio of [DA]r in hypoxia to [DA]r in 100% O2 ranged from 1.3 to 2.2 in the three younger age groups and was 5.5 and 23.3 in 25-day-old and adult rabbits, respectively. We conclude that the release of DA evoked by hypoxia is weak at birth and develops during the first weeks of life in rabbits.

Aging↗
PubMed1996

Improved recovery from laryngeal-stimulation-induced apnea by alpha-adrenergic blockade in adult rabbits.

The apnea triggered by laryngeal stimulation (LS) is associated with a redistribution of blood flow towards the heart and the brain that depends upon peripheral vasoconstriction. The circulatory component of the response to LS has been shown to be reduced following injection of large dose of beta-adrenergic agonist that more intriguingly blunted the ventilatory response as well. To test whether the reduction of LS-induced apnea could be related to the decreased magnitude of the peripheral vasoconstruction, the effects of the alpha-adrenergic antagonist urapidil on the ventilatory and blood pressure responses to LS were studied in 6 adult rabbits. alpha-Adrenergic blockade reduced both the rise in blood pressure and the magnitude of hypopnea induced by LS. These results suggest that the circulatory component of the laryngeal chemoreflex, i.e. the peripheral vasoconstruction, contributes to the magnitude of the ventilatory depression.

Adrenergic beta-Antagonists↗