Retrograde cannulation of the jugular vein.
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Carotid Artery Injuries↗
Biomedical subjects
A Lam
Publications and source records attributed to A Lam.
Intrahepatic bile duct dilatation and cholestasis in autosomal recessive polycystic kidney disease. Demonstration with hepatobiliary scintigraphy.
Fifteen patients with the clinical and radiologic features of autosomal recessive polycystic kidney disease were investigated with radionuclide hepatobiliary scintigraphy. In nine patients (60%), cholestasis and intrahepatic bile duct dilatation were demonstrated. A 10th child had scintigraphic evidence of cholestasis, but the bile ducts were not dilated. The other five children has normal h hepatobiliary scans. The authors conclude that intrahepatic bile duct dilatation with cholestasis (Caroli's disease) is part of the clinical spectrum of autosomal recessive polycystic kidney disease and that hepatobiliary scintigraphy can be of value in determining the extent of hepatobiliary disease in this group of patients.
Bile Ducts↗
Inferior vena cava thrombosis as a complication of femoral vein catheterisation.
Indwelling femoral venous catheters were prospectively studied by ultrasonography to define the frequency and evolution of inferior vena cava (IVC) thrombosis. IVC thrombosis was identified in six of 56 catheters (54 children). Only one patient with a positive ultrasound scan had clinical signs of thrombosis. All children with IVC thrombosis had had catheters in place for over six days. It is recommended that either the femoral central venous catheters are routinely changed at six days or ultrasound studies are routinely performed twice a week in all patients with catheters in situ for six or more days and that the catheter is removed immediately if evidence of thrombosis appears.
Catheterization, Central Venous↗
Effect of the Valsalva maneuver on intracranial hypertension.
We describe a case of intracranial hypertension in a previously healthy 25-year-old man who sustained a head injury in a motor vehicle accident, in whom a Valsalva maneuver resulted in parallel reductions in mean arterial blood pressure, cerebral blood flow velocity in the middle cerebral artery, and intracranial pressure. The effects of raising intrathoracic pressure in patients with intracranial hypertension are discussed.
Adult↗
Comparison of flow and velocity during dynamic autoregulation testing in humans.
BACKGROUND AND PURPOSE: We compared relative changes in middle cerebral artery velocity and internal carotid artery flow during autoregulation testing to test the validity of using transcranial Doppler recordings of middle cerebral artery velocity to evaluate cerebral autoregulation in humans. METHODS: Seven human volunteers had dynamic autoregulation tested during surgical procedures that included exposure of the internal carotid artery. The mean arterial blood pressure and middle cerebral artery velocity spectral outline (Vmax), using transcranial Doppler, and ipsilateral internal carotid artery flow, using an electromagnetic flowmeter, were continuously and simultaneously recorded during transient sharp decreases in blood pressure that were induced by rapid deflation of thigh blood pressure cuffs. The resulting responses of velocity in the middle cerebral artery and flow in the internal carotid artery were compared. RESULTS: Moderate decreases in blood pressure evoked responses in cerebral autoregulation. There were no significant (P = .97) differences between the responses in middle cerebral artery velocity and internal carotid artery flow to the blood pressure decreases. CONCLUSIONS: Relative changes in Vmax accurately reflect relative changes in internal carotid artery flow during dynamic autoregulation testing in humans. Therefore, alterations in middle cerebral artery diameter do not occur to the extent that they introduce a significant error in making these comparisons.
Aged↗
Isoflurane-induced hypotension and vital organ blood flow.
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Animals↗
[Posterior chamber implantation in black Africa. Apropos of 150 cases with an 18 months follow-up].
The purpose of this article is to report our study of 150 cases of posterior chamber implantations carried out at the Hôpital Principal de Dakar between 1988 and 1991. We report the specific difficulties of such operations in black Africans and their complications and follow-up. At the end of this study, after observations over an eighteen month period, we noticed a visual acuity of more than 20/30 for 105 patients (70%) and a secondary cataract in 22 cases (14.6%). Despite less favourable material conditions, we think that such an operation can perfectly be made in Africa and that it gives quite acceptable results.
Adolescent↗
Expression cloning of neurotrophic factors using Xenopus oocytes.
We have explored the potential for cloning novel neurotrophic factor cDNAs via assay of neurotrophic activities following expression in Xenopus oocytes. In this report, we describe the successful application of the method to tract rat ciliary neurotrophic factor (CNTF) activity from mRNA purified from cultured cells and from mRNA synthesized by in vitro transcription of a cDNA library. Rat C6 glioma cells, which had been previously shown to have CNTF-like activity (Westermann et al., 1988), were used as source material. We tested protein extracts of C6 cells using an in vitro assay of primary neurons from the chick ciliary ganglion (CCG assay) and detected a CNTF-like activity. RNA isolated from C6 cells was shown to direct the synthesis of the activity following microinjection into Xenopus oocytes and one-step fractionation of Xenopus extract. C6 mRNA was size-fractionated, and fractions encoding CNTF-like activity were cloned into a lambda phage vector at a site distal to a T7 promoter. Synthetic RNA transcribed from total library DNA was injected into Xenopus oocytes, and a CNTF-like activity in the oocyte extract was detected by the CCG assay. Further fractionation of library clones narrowed the presence of the clone encoding the CNTF-like activity to a pool containing 20,000 members. The presence of a full-length CNTF cDNA clone in this pool and partial clones in other pools was confirmed by Polymerase Chain Reaction (PCR) using oligonucleotides from the rabbit CNTF cDNA (Lin et al., 1989) as primers.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
The potential for fat transplantation.
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Adipose Tissue↗
Effects of therapy in X-linked hypophosphatemic rickets.
BACKGROUND: Patients with X-linked hypophosphatemic rickets, which is clinically manifested by growth failure and bowing of the legs, are usually treated with phosphate and a vitamin D preparation. However, the efficacy of this treatment has been disputed, and nephrocalcinosis is a recognized complication of therapy. METHODS: We studied 24 patients with X-linked hypophosphatemic rickets (9 boys and 15 girls) ranging in age from 1 to 16 years (median, 5.3). The duration of combination therapy ranged from 0.3 to 11.8 years (median, 3.0). We measured height as a standard-deviation (SD) score (the number of SDs from the mean height for chronologic age). Measurements made before the age of two years or after the onset of puberty were excluded. We compared the results with those reported in 1971 for 16 untreated prepubertal Australian patients. We also determined the severity of nephrocalcinosis (on a scale of 0 to 4, with 0 indicating no abnormalities and 4 stone formation) with renal ultrasonography and whether it could be related to the dosage of phosphate or vitamin D or to other factors. RESULTS: Patients treated for at least two years before the onset of puberty (n = 19) had a mean height SD score of -1.08, as compared with -2.05 in the untreated historical controls. The 13 patients who had been treated with calcitriol and phosphate for at least two years had an increase in the mean height SD score of 0.33, from -1.58 to -1.25 (95 percent confidence interval, 0 to 0.67; P = 0.05). Nineteen of the 24 patients (79 percent) had nephrocalcinosis detected on renal ultrasonography. The grade of nephrocalcinosis was significantly correlated with the mean phosphate dose (r = 0.60, P = 0.002), but not with the dose of vitamin D or the duration of therapy. All patients had normal serum creatinine concentrations. CONCLUSIONS: Therapy with calcitriol and phosphate may increase the growth of children with X-linked hypophosphatemic rickets. Nephrocalcinosis in these children represents a complication of therapy and is associated with the dose of phosphate received.
Body Height↗
Sequence and structural organization of the human gene encoding ciliary neurotrophic factor.
Ciliary neurotrophic factor (CNTF) is a potent polypeptide hormone whose actions appear to be restricted to the nervous system where it promotes survival, neurotransmitter synthesis and neurite outgrowth in certain neuronal populations. We have cloned the gene encoding human CNTF (hCNTF) and have characterized its structure and organization. The hCNTF gene appears to be a unique-copy gene with a simple genetic organization, since only a single intron interrupts the coding domain. The hCNTF gene is located on chromosome 11, as determined using human-hamster somatic cell hybrids. The CNTF protein is highly conserved in evolution. The amino acid (aa) sequences of rat and rabbit CNTF translated from cDNAs display approx. 85% homology with the deduced aa sequence encoding hCNTF.
Amino Acid Sequence↗
Epinephrine-containing test dose during beta-blockade.
Epinephrine is routinely used as a marker for intravascular injection during administration of regional anesthesia. The cardiovascular response of patients on beta-blockers to such a test dose has been reported to be unpredictable. We investigated this interaction by administering 15 micrograms of epinephrine intravenously to 6 healthy volunteers 39 to 48 years old before and after beta-blockade, accomplished by intravenous injection of propranolol, 0.04 mg/kg. Epinephrine administration caused a 20 +/- 4% (mean +/- SEM) increase in heart rate before beta-blockade but a 38 +/- 3% reduction after beta-blockade. The lowest heart rate recorded was 28 beats/min. We conclude that, in middle-aged beta-blocked men, intravenous injection of a standard epinephrine-containing test dose will predictably cause significant hypertension followed by marked bradycardia.
Adrenergic beta-Antagonists↗
Arterial desaturation during induction in healthy adults: should preoxygenation be a routine?
We studied the haemoglobin saturation of one hundred healthy patients equally divided into two groups. Group 1 patients received three minutes of preoxygenation prior to thiopentone induction followed by inhalational anaesthetics. Group 2 patients breathed room air prior to induction. None of the patients in Group 1 showed any arterial oxygen desaturation during the five minutes of the induction period, whereas 21 patients in Group 2 showed definite desaturation (P less than 0.005), of which fifteen patients had a saturation of 90% or less (P less than 0.005) and six had a saturation of 85% or less. Since those were healthy patients and the anaesthetics were given by experienced anaesthetists, we concluded that some form of preoxygenation should be used in all patients receiving general anaesthesia.
Adolescent↗
Extradural hematoma in neonates.
Six neonates with extradural hematomas (EDH) diagnosed by ultrasound and confirmed by computed tomography scan were reviewed. EDH was seen in term male infants of primigravidas. Predisposing factors were coagulopathy and forceps extraction after prolonged labor. Clinical features were similar to other intracranial hemorrhages, but no deterioration in the level of consciousness was noted. Constant ultrasonographic features include a biconvex, echogenic, intracranial mass adjacent to the inner table of the skull. Ultrasonography was shown to be a reliable tool in establishing the diagnosis, monitoring progress, and detecting complications of EDH. Recovery with conservative management was noted.
Cerebral Hemorrhage↗
[Treatment of Mooren's ulcer by the combination of periectomy and corticotherapy. Apropos of 6 cases].
In this article, the authors recall the two clinical forms of Mooren ulcer (the classical and torpid one, and the inflammatory one), the autoimmune hypothesis which is unanimously accepted to explain its pathophysiology and the therapeutic problems because of the frequency of recurrences. On the basis of 6 cases (2 classical forms and 4 inflammatory) studied from 1988 to 1990 in patients with a mean age of 35 years all of them black Senegalese, they propose a new kind of treatment combining a periectomy and local and systemic corticosteroids. They stress the success of such a combination: the healing of the ulcer is rapid (35 days on average). The inflammatory form heals more rapidly (14 days, number 4) than the classical one (4 months, case number 6) without any recurrence one year later. They try to propose a pathophysiological explanation for this success: the periectomy seems to suppress the cause of the (immunate) conflict and to have an autohemotherapic action; corticosteroids seem to be both immunosuppressive and anti-inflammatory. The authors would like to extend their experiment to larger series.
Adrenal Cortex Hormones↗
[Spontaneous expulsive hemorrhage after total necrosis of the cornea. Apropos of 3 cases].
Three cases of spontaneous expulsive haemorrhage during the year 1990 are presented in this publication. They represent the dramatic outcome of an ulcero-necrotic syndrome of the cornea with disorganization of the anterior segment, which is frequent of tropical areas. Only a few cases have been reported in the literature. The factors related to their development, could contribute to the knowledge of the pathophysiology of expulsive haemorrhages in general. A spontaneous haemorrhage is always a very distressing complication. The treatment consisted in completing the spontaneous evisceration. The means of prevention are tricky. Faced with such a predisposition, an evisceration can be proposed. But, it is not well accepted by the patients.
Adult↗
Management of asthma and chronic airflow limitation: are methylxanthines obsolete?
The widespread popularity of methylxanthine derivatives should be reassessed in light of current evidence. These drugs are relatively weak bronchodilators, respiratory muscle stimulants and inotropic agents and adverse effects, sometimes life threatening, occur fairly frequently. In contrast, beta-2 adrenergic and anticholinergic bronchodilator aerosols used in asthma or chronic obstructive lung disease, and the prophylactic anti-inflammatory aerosols of corticosteroids and cromolyn provide a spectrum of therapeutic choices which address both the inflammatory and bronchoconstrictor components of acute and chronic airflow limitation. Aerosol bronchodilators, in general, are more potent, are virtually free of important side effects, and do not require costly serum level monitoring. Adrenoceptor agonists, together with inhaled steroids, should be considered first-line drugs of choice in managing patients with reversible airflow obstruction associated with asthma or COPD, while methylxanthines should be relegated to the position of third or fourth line drugs, if they are to be used at all. If they are, they should be used with great caution and close patient supervision and, even then, only if benefit, over and above the aerosol bronchodilators and inhaled anti-inflammatory agents can be demonstrated objectively.
Adrenal Cortex Hormones↗
Management of asthma and chronic airflow limitation. Are methylxanthines obsolete?
After almost 50 years as first-line drugs in the management of asthma and COPD, methylxanthines have been largely superceded by inhaled adrenoceptor agonist and anticholinergic bronchodilators which are more potent and far less toxic. Accumulating evidence indicates that intravenous theophylline contributes side effects, but is rarely of benefit in acute exacerbations of asthma or COPD. In the maintenance therapy of asthma, first-line therapy is dose-optimized inhaled steroids, reducing the need for bronchodilators. Inhaled adrenoceptor agonists are second line medications, anticholinergic aerosols third line, and theophylline, if needed at all, may fulfill a minor systemic steroid-sparing function in severe asthmatics on maximum doses of the inhaled medications. In the maintenance therapy of some patients with COPD, theophylline sometimes may be useful but these responders should be identified by objectively establishing therapeutic benefit. Since many patients have side effects from the methylxanthines, while their therapeutic benefit over and above dose-optimized inhaled therapy is marginal, their continued almost routine use in the management of reversible airflow obstruction is hard to justify, although this class of drugs may be useful in selected patients in whom both subjective and objective benefit can be demonstrated. In COPD, theophylline may improve exercise capacity in some patients by still incompletely understood mechanisms probably unrelated to bronchodilation.
Administration, Inhalation↗