Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 29
Filter
1.
Br J Anaesth ; 116(3): 405-12, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26865133

ABSTRACT

BACKGROUND: Ultrasound guidance allows for the use of much lower volumes of local anaesthetics for nerve blocks, which may be associated with less aberrant spread and fewer complications. This randomized, controlled study used contrast magnetic resonance imaging to view the differential-volume local anaesthetic distribution, and compared analgesic efficacy and respiratory impairment. METHODS: Thirty patients undergoing shoulder surgery were randomized to receive ultrasound-guided interscalene block by a single, blinded operator with injection of ropivacaine 0.75% (either 20 or 5 ml) plus the contrast dye gadopentetate dimeglumine, followed by magnetic resonance imaging. The primary outcome was epidural spread. Secondary outcomes were central non-epidural spread, contralateral epidural spread, spread to the phrenic nerve, spirometry, ultrasound investigation of the diaphragm, block duration, pain scores during the first 24 h, time to first analgesic consumption, and total analgesic consumption. RESULTS: All blocks provided fast onset and adequate intra- and postoperative analgesia, with no significant differences in pain scores at any time point. Epidural spread occurred in two subjects of each group (13.3%); however, spread to the intervertebral foramen and phrenic nerve and extensive i.m. local anaesthetic deposition were significantly more frequent in the 20 ml group. Diaphragmatic paralysis occurred twice as frequently (n=8 vs 4), and changes from baseline peak respiratory flow rate were larger [Δ=-2.66 (1.99 sd) vs -1.69 (2.0 sd) l min(-1)] in the 20 ml group. CONCLUSIONS: This study demonstrates that interscalene block is associated with epidural spread irrespective of injection volume; however, less central (foraminal) and aberrant spread after low-volume injection may be associated with a more favourable risk profile. CLINICAL TRIAL REGISTRATION: This study was registered with the European Medicines Agency (Eudra-CT number 2013-004219-36) and with the US National Institutes' of Health registry and results base, clinicaltrials.gov (identifier NCT02175069).


Subject(s)
Anesthetics, Local/pharmacokinetics , Contrast Media , Magnetic Resonance Imaging , Nerve Block , Phrenic Nerve/drug effects , Ultrasonography, Interventional , Adolescent , Adult , Aged , Amides/pharmacokinetics , Brachial Plexus/diagnostic imaging , Brachial Plexus/drug effects , Epidural Space , Female , Gadolinium DTPA , Humans , Image Enhancement , Male , Middle Aged , Ropivacaine , Shoulder/surgery , Tissue Distribution , Young Adult
2.
Br J Anaesth ; 114(2): 319-26, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25145353

ABSTRACT

BACKGROUND: The neuropathy of type II diabetes mellitus (DM) is increasing in prevalence worldwide. We aimed to test the hypothesis that in a rodent model of type II DM, neuropathy would lead to increased neurotoxicity and block duration after lidocaine-induced sciatic nerve block when compared with control animals. METHODS: Experiments were carried out in Zucker diabetic fatty rats aged 10 weeks (early diabetic) or 18 weeks (late diabetic, with or without insulin 3 units per day), and age-matched healthy controls. Left sciatic nerve block was performed using 0.2 ml lidocaine 2%. Nerve conduction velocity (NCV) and F-wave latency were used to quantify nerve function before, and 1 week after nerve block, after which sciatic nerves were used for neurohistopathology. RESULTS: Early diabetic animals did not show increased signs of nerve dysfunction after nerve block. In late diabetic animals without insulin vs control animals, NCV was 34.8 (5.0) vs 41.1 (4.1) ms s(-1) (P<0.01), and F-wave latency was 7.7 (0.5) vs 7.0 (0.2) ms (P<0.01), respectively. Motor nerve block duration was prolonged in late diabetic animals, but neurotoxicity was not. Late diabetic animals receiving insulin showed intermediate results. CONCLUSIONS: In a rodent type II DM model, nerves have increased sensitivity for short-acting local anaesthetics without adjuvants in vivo, as evidenced by prolonged block duration. This sensitivity appears to increase with the progression of neuropathy. Our results do not support the hypothesis that neuropathy due to type II DM increases the risk of nerve injury after nerve block.


Subject(s)
Diabetic Neuropathies/complications , Nerve Block/methods , Neurotoxicity Syndromes/physiopathology , Sciatic Nerve , Aging/physiology , Animals , Blood Glucose/metabolism , Body Weight/drug effects , Electrophysiological Phenomena/drug effects , Neurotoxicity Syndromes/pathology , Rats , Rats, Zucker , Sciatic Nerve/pathology
3.
Bone Joint J ; 96-B(2): 242-8, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24493191

ABSTRACT

Despite the increasing prevalence of sleep apnoea, little information is available regarding its impact on the peri-operative outcome of patients undergoing posterior lumbar fusion. Using a national database, patients who underwent lumbar fusion between 2006 and 2010 were identified, sub-grouped by diagnosis of sleep apnoea and compared. The impact of sleep apnoea on various outcome measures was assessed by regression analysis. The records of 84,655 patients undergoing posterior lumbar fusion were identified and 7.28% (n = 6163) also had a diagnostic code for sleep apnoea. Compared with patients without sleep apnoea, these patients were older, more frequently female, had a higher comorbidity burden and higher rates of peri-operative complications, post-operative mechanical ventilation, blood product transfusion and intensive care. Patients with sleep apnoea also had longer and more costly periods of hospitalisation. In the regression analysis, sleep apnoea emerged as an independent risk factor for the development of peri-operative complications (odds ratio (OR) 1.50, confidence interval (CI) 1.38;1.62), blood product transfusions (OR 1.12, CI 1.03;1.23), mechanical ventilation (OR 6.97, CI 5.90;8.23), critical care services (OR 1.86, CI 1.71;2.03), prolonged hospitalisation and increased cost (OR 1.28, CI 1.19;1.37; OR 1.10, CI 1.03;1.18). Patients with sleep apnoea who undergo posterior lumbar fusion pose significant challenges to clinicians.


Subject(s)
Lumbar Vertebrae/surgery , Population Surveillance , Postoperative Complications/etiology , Risk Assessment/methods , Sleep Apnea Syndromes/epidemiology , Spinal Diseases/surgery , Spinal Fusion/methods , Adult , Aged , Female , Follow-Up Studies , Humans , Male , Middle Aged , Postoperative Complications/epidemiology , Prevalence , Prognosis , Retrospective Studies , Risk Factors , Sleep Apnea Syndromes/complications , Sleep Apnea Syndromes/diagnosis , Spinal Diseases/complications , United States/epidemiology
4.
Pediatr Transplant ; 17(7): 694-706, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24004351

ABSTRACT

Controlled trials of mTOR inhibitors in children following solid organ transplantation are scarce, although evidence from prospective single-arm studies is growing. Everolimus with reduced CNI therapy has been shown to be efficacious and safe in de novo pediatric kidney transplant patients in prospective trials. Prospective and retrospective data in children converted from CNI therapy to mTOR inhibition following kidney, liver, or heart transplantation suggest preservation of immunosuppressive efficacy. Good renal function has been maintained when mTOR inhibitors are used de novo in children following kidney transplantation or after conversion to mTOR inhibition with CNI minimization. mTOR inhibition with reduced CNI exposure is associated with a low risk for developing infection in children. Growth and development do not appear to be impaired during low-dose mTOR inhibition, but more studies are required. No firm conclusions can be drawn as to whether mTOR inhibitors should be discontinued in children requiring surgical intervention or whether mTOR inhibition delays progression of hepatic fibrosis after pediatric liver transplantation. In conclusion, current evidence suggests that use of mTOR inhibitors in children undergoing solid organ transplantation is efficacious and safe, but a number of issues remain unresolved and further studies are required.


Subject(s)
Calcineurin Inhibitors , Heart Transplantation , Immunosuppressive Agents/administration & dosage , Kidney Transplantation , Liver Transplantation , TOR Serine-Threonine Kinases/antagonists & inhibitors , Child , Everolimus , Fibrosis/pathology , Humans , Liver/pathology , Lymphoproliferative Disorders/prevention & control , Postoperative Complications/prevention & control , Risk , Sirolimus/administration & dosage , Sirolimus/analogs & derivatives , Treatment Outcome , Wound Healing
5.
Adv Virol ; 2012: 670316, 2012.
Article in English | MEDLINE | ID: mdl-22496689

ABSTRACT

Background. It has been suggested that chronic hepatitis B infection leads to growth impairment, but data are inconsistent and underlying factors are not defined. Methods. Children and adolescents with chronic hepatitis B (HBV) or C (HCV) were retrospectively evaluated for growth, weight, antiviral treatment, biochemical signs of liver inflammation, route of infection, and HBV DNA, respectively. Results. In all, 135 children (mean age 6.1 years, 81 male, 54 female) with HBV (n = 78) or HCV (n = 57) were studied. Route of infection was vertical in 50%, parenteral in 11%, and unknown in 39%. ALT levels were above 1.5 times above normal in 30% while 70% had normal/near normal transaminases. 80% were Caucasian, 14% Asian, 1% black, and 4% unknown. Mean baseline height measured in SDS was significantly lower in the study population than in noninfected children (boys -1.2, girls -0.4, P < 0.01). 28 children were below 2 standard deviations of the norm while 5 were above 2 standard deviations. SDS measures in relation to individual factors were as follows: elevated ALT: boys -1.4, females -0.5 (P < 0.01), ALT normal/near normal: boys +0.4, females +0.6; parenteral transmission: boys -3.3, girls -0.9 (P < 0.01), vertical transmission: boys -0.2, females -0.2. Antiviral treatment itself or HBV-DNA load did not reach statistically significant differences. Conclusions. Chronic HBV or HCV may lead to compromised growth which is mostly influenced by liver inflammation. Our data may argue for early antiviral treatment in children with significant ALT elevation.

6.
Pediatr Transplant ; 15(6): E126-9, 2011 Sep.
Article in English | MEDLINE | ID: mdl-20331520

ABSTRACT

HHV type 6 has been reported with enhanced pathogenicity in immunocompromised patients. Herein, we report about a two-yr-old girl who experienced primary HHV 6 infection after liver transplantation. She clinically presented with graft rejection and necrotic hepatitis as well as high fever, pneumonitis with respiratory failure and a rash. Therapy with cidofovir of 5 mg/kg per wk did not show improvement, so that a full pharmacokinetic profile of cidofovir was performed. It demonstrated enhanced body weight normalized clearance of cidofovir and cidofovir dosage was augmented to 12 mg/kg per wk to reach adequate drug exposure. With additional reduction of immunosuppression, the patient dramatically improved and liver function stabilized.


Subject(s)
Antiviral Agents/therapeutic use , Cytosine/analogs & derivatives , Graft Rejection , Herpesviridae Infections/diagnosis , Herpesvirus 6, Human/metabolism , Liver Transplantation/methods , Organophosphonates/therapeutic use , Child, Preschool , Cholestasis, Intrahepatic/therapy , Cidofovir , Cytosine/therapeutic use , Female , Hepatitis/pathology , Herpesviridae Infections/pathology , Humans , Immunosuppression Therapy , Immunosuppressive Agents/therapeutic use , Liver Cirrhosis/therapy , Necrosis
7.
J Viral Hepat ; 16(12): 853-9, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19682316

ABSTRACT

Viral genome analyses performed in adult HCV-patients yielded very inconsistent results and are not transferable to children who are often infected vertically during a state of high immune tolerance. We analysed the mutational frequency in the PKR-binding domain (PKR-BD) of NS5A and PePHD of E2 protein pre- and post-treatment with peginterferon-alfa-2b and ribavirin in children chronically infected with HCV genotype 1. Amino acid sequences of NS5A (2 209-2 274) and E2 (618-681) were determined in serum samples using standard PCR procedures. Concerning the PKR-BD a significant higher number of mutations was observed in vertically compared to horizontally infected patients (2.14 vs 1.24, P-value = 0.03). This difference was exclusively based on the increased number of mutations in responders vs non-responders in vertically infected patients (2.95 vs 1.33; P-value = 0.02). While all patients with at least four mutations (n = 3) did respond to therapy, no other predictive parameters could be identified. In the PePHD no differences could be observed between either of these groups. These findings support the idea that viral properties, mode and therewith time of infection in terms of immune tolerance are equally important factors for predicting SVR in children. However given the low number of cases further studies are required to confirm this hypothesis.


Subject(s)
Antiviral Agents/therapeutic use , Hepacivirus/genetics , Hepatitis C, Chronic/virology , Interferon-alpha/therapeutic use , Mutation, Missense , Polyethylene Glycols/therapeutic use , Ribavirin/therapeutic use , Viral Nonstructural Proteins/genetics , Adolescent , Amino Acid Sequence , Child , Child, Preschool , Disease Transmission, Infectious , Female , Hepacivirus/isolation & purification , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/transmission , Humans , Infectious Disease Transmission, Vertical , Interferon alpha-2 , Male , Molecular Sequence Data , Polymerase Chain Reaction/methods , Recombinant Proteins , Sequence Analysis, DNA , Treatment Outcome , Viral Envelope Proteins/genetics , Young Adult
8.
Eur J Anaesthesiol ; 24(8): 702-8, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17437653

ABSTRACT

BACKGROUND AND OBJECTIVE: Tricyclic antidepressants are commonly employed orally to treat major depressive disorders and have been shown to be of substantial benefit in various chronic pain conditions. Among other properties they are potent Na+ channel blockers in vitro and show local anaesthetic properties in vivo. The present study aimed to determine their differential neurotoxicity, and that of novel derivatives as prerequisite for their potential use in regional anaesthesia. METHODS: To directly test neurotoxicity in adult peripheral neurons, the culture model of dissociated adult rat primary sensory neurons was employed. Neurons were incubated for 24 h with amitriptyline, N-methyl-amitriptyline, doxepin, N-methyl-doxepin, N-propyl-doxepin, desipramine, imipramine and trimipramine at 100 mumol, and at concentrations correlating to their respective potency in blocking sodium channels. RESULTS: All investigated substances showed considerable neurotoxic potency as represented in significantly decreased neuron numbers in cultures as compared to controls. Specifically, doxepin was more neurotoxic than amitriptyline, and both imipramine and trimipramine were more toxic than desipramine or amitriptyline. Novel derivatives of tricyclic antidepressants were, in general, more toxic than the parent compound. CONCLUSIONS: Tricyclic antidepressants and novel derivatives thereof show differential neurotoxic potential in vitro. The rank order of toxicity relative to sodium channel blocking potency was desipramine < amitriptyline < N-methyl amitriptyline < doxepin < trimipramine < imipramine < N-methyl doxepin < N-propyl doxepin.


Subject(s)
Amitriptyline/toxicity , Anesthesia, Conduction , Anesthetics, Local/toxicity , Antidepressive Agents, Tricyclic/toxicity , Amitriptyline/analogs & derivatives , Animals , Apoptosis/drug effects , Cell Count , Cell Culture Techniques/methods , Dose-Response Relationship, Drug , Doxepin/analogs & derivatives , Doxepin/toxicity , Electric Impedance , Female , Ganglia, Spinal , Imipramine/analogs & derivatives , Imipramine/toxicity , Pain/drug therapy , Rats , Rats, Sprague-Dawley , Sodium Channels/drug effects , Time Factors
9.
Chemistry ; 13(4): 1152-7, 2007.
Article in English | MEDLINE | ID: mdl-17066492

ABSTRACT

Near-infrared to visible upconversion luminescence in CsCaCl3:Tm2+, CsCaBr3:Tm2+ and CsCaI3:Tm2+ is presented and analysed. The upconversion process involves exclusively the 4f-5d excited states of Tm2+, which is a novelty among upconversion materials. The presence of more than one long-lived 4f-5d excited state is the prerequisite for this. Multiple emissions from Tm2+ are observed in the title compounds. This is made possible by the favourable energy structure within the 4f-5d states and the low phonon energies of the materials. The energy positions of the relevant 4f-5d states, and thus the photophysical and light emission properties, are affected by the chemical variation along the series. The upconversion efficiency increases from chloride to iodide and the mechanism is found to be a combination of absorption and energy-transfer steps.

11.
J Autoimmun ; 24(1): 79-84, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15725580

ABSTRACT

OBJECTIVE: Evaluation of systematic epidemiological data regarding clinical characteristics, sex distribution and autoantibody pattern in Caucasian children with autoimmune hepatitis (AIH). STUDY DESIGN: Data of 142 children presenting with AIH (97 girls and 45 boys) have been analysed for their clinical, serological, and histological profile. RESULTS: Clinical findings were jaundice (58%), unspecific weakness (57%), anorexia (47%), abdominal pain (38%) and paleness (26%). One hundred and three children (73%) (68 girls, 35 boys, 1.9:1) had AIH type 1 and 35 patients (25%) (27 girls, 8 boys, 3.4:1) type 2 due to specific autoantibodies. Four children could not be classified. Histology of 122 children revealed active hepatitis in 64 (52%), cirrhosis in 46 (38%), and mild inflammatory activity in 12 individuals (10%). The most prevalent HLA type was B8. CONCLUSION: In our cohort the prevalence of AIH was half as frequent in boys as in girls. Type 1 was the most frequent diagnosis (73%) and was more prevalent in older children. Type 2 was equally age distributed. The clinical presentation of AIH in children was unspecific and type I and type II could only be differentiated by the determination of the specific autoantibodies. Ninety percent of patients presented with high inflammatory activity or liver cirrhosis.


Subject(s)
Hepatitis, Autoimmune/immunology , Hepatitis, Autoimmune/physiopathology , White People , Adolescent , Adult , Autoantibodies/immunology , Child , Child, Preschool , Female , Hepatitis, Autoimmune/diagnosis , Hepatitis, Autoimmune/epidemiology , Humans , Infant , Male
13.
Anesthesiology ; 95(5): 1198-204, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11684990

ABSTRACT

BACKGROUND: Local anesthetics that produce analgesia of long duration with minimal impairment of autonomic functions are highly desirable for pain management in the clinic. Prenylamine is a known calcium channel blocker, but its local anesthetic blocking effects on voltage-gated sodium channels have not been studied thus far. METHODS: The authors characterized the tonic and use-dependent prenylamine block of native Na(+) channels in cultured rat neuronal GH3 cells during whole cell voltage clamp conditions and the local anesthetic effect of prenylamine by neurologic evaluation of sensory and motor functions of sciatic nerve during neural block in rats. RESULTS: Prenylamine elicits both use-dependent block of Na(+) channels during repetitive pulses (3 microm prenylamine produced 50% block at 5 Hz) and tonic block for both resting and inactivated Na(+) channels. The 50% inhibitory concentration for prenylamine was 27.6 +/- 1.3 microm for resting channels and 0.75 +/- 0.02 microm for inactivated channels. Furthermore, in vivo data show that 10 mm prenylamine produced a complete sciatic nerve block of motor function, proprioceptive responses, and nociceptive responses that lasted approximately 27, 34, and 24 h, respectively. Rats injected with 15.4 mm bupivacaine, a known local anesthetic currently used for pain management, had a significantly shorter duration of blockade (< 2 h) compared with rats injected with prenylamine. CONCLUSIONS: The data presented here demonstrate that prenylamine possesses local anesthetic properties in vitro and elicits prolonged local anesthesia in vivo.


Subject(s)
Anesthetics, Local/pharmacology , Bupivacaine/pharmacology , Calcium Channel Blockers/pharmacology , Prenylamine/pharmacology , Sodium Channels/drug effects , Animals , Cells, Cultured , Male , Nerve Block , Pain/prevention & control , Patch-Clamp Techniques , Rats , Rats, Sprague-Dawley , Sciatic Nerve/drug effects
14.
Inorg Chem ; 40(18): 4534-42, 2001 Aug 27.
Article in English | MEDLINE | ID: mdl-11511196

ABSTRACT

Direct near-IR excitation of Yb(3+) 2F(7/2)-->(2)F(5/2) levels at 10126, 10138, and 10596 cm(-1) in CsMnBr3:0.5%Yb(3+) leads to three types of luminescence at cryogenic temperatures: near-IR Yb(3+) emission and green and red upconverted luminescence. The green luminescence around 20 000 cm(-1) is identified as cooperative Yb(3+) pair upconversion. The broad red upconversion luminescence band centered at 14 700 cm(-1) is ascribed to the 4T(1g)-->6A(1g) transition of Mn(2+). Pulsed measurements indicate a sequence of ground-state absorption and excited-state absorption steps for the red upconversion process. One- and two-color excitation experiments support this, and we conclude that the red upconversion occurs by an exchange mechanism involving Yb(3+) and Mn(2+). The Yb(3+) 2F(5/2)-->(2)F(7/2) near-IR emission around 10 000 cm(-1) is also observed after Mn(2+) excitation at 21 838 cm(-1). This is indicative of a Mn(2+) 4T(1g)--> Yb(3+) 2F(5/2) relaxation process, which is a potential loss process for upconversion efficiency.

15.
Anesthesiology ; 94(4): 661-7, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11379688

ABSTRACT

BACKGROUND: Amitriptyline, a tricyclic antidepressant, is frequently used orally for the management of chronic pain. To date there is no report of amitriptyline producing peripheral nerve blockade. The authors therefore investigated the local anesthetic properties of amitriptyline in rats and in vitro. METHODS: Sciatic nerve blockade was performed with 0.2 ml amitriptyline or bupivacaine at selected concentrations, and the motor, proprioceptive, and nociceptive blockade was evaluated. Cultured rat GH3 cells were externally perfused with amitriptyline or bupivacaine, and the drug affinity toward inactivated and resting Na+ channels was assessed under whole-cell voltage clamp conditions. In addition, use-dependent blockade of these drugs at 5 Hz was evaluated. RESULTS: Complete sciatic nerve blockade for nociception was obtained with amitriptyline for 217 +/- 19 min (5 mM, n = 8, mean +/- SEM) and for 454 +/- 38 min (10 mM, n = 7) versus bupivacaine for 90 +/- 13 min (15.4 mM, n = 6). The time to full recovery of nociception for amitriptyline was 353 +/- 12 min (5 mM) and 656 +/- 27 min (10 mM) versus 155 +/- 9 min for bupivacaine (15.4 mM). Amitriptyline was approximately 4.7-10.6 times more potent than bupivacaine in binding to the resting channels (50% inhibitory concentration [IC50] of 39.8 +/- 2.7 vs. 189.6 +/- 22.3 microM) at - 150 mV, and to the inactivated Na+ channels (IC50 of 0.9 +/- 0.1 vs. 9.6 +/- 0.9 microM) at -60 mV. High-frequency stimulation at 3 microM caused an additional approximately 14% blockade for bupivacaine, but approximately 50% for amitriptyline. CONCLUSION: Amitriptyline is a more potent blocker of neuronal Na+ channels than bupivacaine in vivo and in vitro. These findings suggest that amitriptyline could extend its clinical usefulness for peripheral nerve blockade.


Subject(s)
Amitriptyline/pharmacology , Analgesics, Non-Narcotic/pharmacology , Anesthetics, Local/pharmacology , Bupivacaine/pharmacology , Sciatic Nerve/drug effects , Sodium Channel Blockers , Animals , Dose-Response Relationship, Drug , Male , Rats , Rats, Sprague-Dawley , Time Factors
16.
Pediatr Infect Dis J ; 19(11): 1074-7, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11099089

ABSTRACT

OBJECTIVE: It is currently unknown which mechanisms are responsible for TT virus (TTV) infection in early childhood and whether it may be transmitted in utero from mother to infant. METHODS: The prevalence, mode and extent of maternal TTV transmission was investigated by testing blood, cord blood and breast milk samples from mother-infant pairs for the existence of the novel DNA virus. RESULTS: By means of polymerase chain reaction, TTV DNA was detected in 57 (41.3%) of 138 mothers and in 19 (13.8%) of 138 cord blood samples; therefore 33.3% of infants are likely to be infected by their mothers during the fetal period. Direct sequencing of TTV DNA from 2 mother-child pairs showed identical isolates. Follow-up sera from 3 TTV infected babies showed persistence of viremia. In blood samples from newborns older than 1 week 9 (27.3%) of 33 sera were TTV-positive. Viral sequences were also detected in 2 of 2 breast milk samples. In none of the infected subjects were biochemical or clinical signs of hepatitis observed. CONCLUSIONS: Our data prove that TT virus is efficiently transmitted transplacentally. The increase of its prevalence in the group of newborns older than 1 week suggests that it may be furthermore transmitted postnatally. Therefore in our Caucasian population, vertical transmission, particularly in utero transmission, of TTV is likely to account for a major part of TTV infection in early childhood. However, no disease activity could be established for the novel virus by this infection route.


Subject(s)
DNA Virus Infections/transmission , Infectious Disease Transmission, Vertical , Torque teno virus/isolation & purification , Adult , Base Sequence , DNA, Viral/analysis , Female , Humans , Infant, Newborn , Molecular Sequence Data , Pregnancy , Prevalence , Sequence Alignment
17.
J Pediatr ; 136(5): 606-10, 2000 May.
Article in English | MEDLINE | ID: mdl-10802491

ABSTRACT

BACKGROUND: The existence of a novel human virus, designated TT virus (TTV), has been reported in association with acute and chronic liver disease of unknown cause. OBJECTIVES: To evaluate the prevalence and clinical significance of TTV infection in childhood. STUDY DESIGN: Sera from 104 healthy children, 85 patients with chronic hepatitis B (HBV) and 29 with chronic hepatitis C (HCV), were tested by polymerase chain reaction with primers corresponding to conserved regions within a part of ORF 2. To characterize polymerase chain reaction products, TTV isolates from 15 subjects were directly sequenced. RESULTS: TTV DNA was detected in 22 (21%) of 104 healthy children and in 55 (65%) of 85 and 20 (69%) of 29 HBV- and HCV-infected individuals, respectively. No significant difference was observed in aminotransferase levels of HBV- or HCV-infected patients with or without TTV coinfection. Sequence analysis showed a high degree of genetic heterogeneity between TTV isolates. CONCLUSIONS: A striking difference was found in the prevalence of TTV between healthy children and patients with chronic HBV or HCV infection (P <.0005). However, based on these results, TTV alone or as coinfection does not seem to cause or exacerbate liver damage in childhood.


Subject(s)
Hepatitis B, Chronic/virology , Hepatitis C, Chronic/virology , Hepatitis, Viral, Human/virology , Child , Female , Humans , Male
18.
Anesthesiology ; 92(5): 1350-60, 2000 May.
Article in English | MEDLINE | ID: mdl-10781281

ABSTRACT

BACKGROUND: Long-acting local anesthetics are beneficial for the management of postoperative pain and chronic pain. The authors recently reported that a single injection of N-beta-phenylethyl-lidocaine (tonicaine), a quaternary lidocaine derivative, effectively blocks rat sciatic nerve function four to nine times longer than lidocaine, with a predominance of sensory versusmotor blockade. The purposes of this study were to measure directly the potency of this charged drug by internal perfusion of cultured neuronal cells, and to evaluate the differential blockade of sensory versus motor function via spinal route in rats. METHODS: The tonic and additional use-dependent blockade of Na+ currents by internal tonicaine was assayed in cultured GH3 cells during whole cell voltage-clamp conditions. In addition, tonicaine was injected into the intrathecal space of rats at intervertebral space L4-L5, and the proprioceptive, motor, and sensory functions, and tissue integrity, subsequently were evaluated. RESULTS: Internal application of tonicaine in GH3 cells revealed that it was approximately 80 times more potent in blocking Na+ currents than was externally applied lidocaine. In vivotesting in a rat neuraxial anesthesia model showed that tonicaine at 0.5 mm produced blockade that lasted much longer than that produced by bupivacaine even at approximately a 55 times higher concentration (28.8 mm). Tonicaine spinal block also produced a longer duration of sensory than motor blockade (112.5 +/- 16.3 min vs. 45.8 +/- 7.1 min). Evidence of neurotoxicity was seen at a concentration of 1.0 mm. CONCLUSION: In vitro testing shows that tonicaine displays a higher affinity for the local anesthetic binding site than does lidocaine; in vivotesting indicates that tonicaine elicits sensory blockade of a duration significantly longer than that elicited by bupivacaine. Tonicaine, however, has a narrow therapeutic index, with substantial neurotoxicity at 1 mm in rats, and may have limited clinical value.


Subject(s)
Anesthetics, Local/pharmacology , Lidocaine/analogs & derivatives , Motor Neurons/drug effects , Neurons, Afferent/drug effects , Analysis of Variance , Anesthetics, Local/administration & dosage , Anesthetics, Local/chemistry , Animals , Cells, Cultured , Injections, Spinal , Lidocaine/administration & dosage , Lidocaine/chemistry , Lidocaine/pharmacology , Male , Neuromuscular Blockade , Patch-Clamp Techniques , Rats , Rats, Sprague-Dawley , Sodium Channels/drug effects , Spinal Cord/pathology , Structure-Activity Relationship
19.
J Med Virol ; 59(4): 415-23, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10534721

ABSTRACT

Sera of two children were examined to determine whether specific hepatitis B virus (HBV) mutants may contribute to anti-hepatitis B e/hepatitis B e antigen (anti-HBe/HBeAg) reactivations during the course of chronic hepatitis B. The full-length HBV genome isolated from sera of patient 1 and the basic core promoter (BCP) from patient 2 were amplified and sequenced before and after several reactivations. The functional significance of the mutant BCP from patient 1 was studied using the luciferase assay. In both patients, rare mutations were found in the BCP at nucleotides 1764(G-->T)/1766(C-->G) and 1766(C-->T)/1768(T-->A) in case 1 and 2, respectively. In the BCP from patient 1, a putative new binding site for the transcription factor hepatocyte nuclear factor 3 (HNF3) was generated. The functional analyses of the mutant showed a 2.8-fold increase of core promoter activity, whereas the BCP variant of patient 2 was also identified to result in enhanced promoter activity. The alignment of full-length genomes from child 1 to the reference sequence showed 61 nucleotide substitutions. Furthermore, the time of reactivations from child 1 was always accompanied by selection of a precore mutation at nucleotide position 1899. In liver tissue of patient 1 before development of hepatocellular carcinoma only free viral sequences were found, whereas a single site integration of HBV was detected in hepatocytes after activation of carcinogenesis. Specific mutations in the HBV BCP of the two patients that are rarely present in chronic carriers were identified to increase the core promoter activity possibly by altering transcription factor binding, suggesting that these variants may be involved in the pathogenesis of frequent HBV reactivations.


Subject(s)
Hepatitis B e Antigens/immunology , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Mutation , Promoter Regions, Genetic , Viral Core Proteins/genetics , Adolescent , Amino Acid Substitution , Base Sequence , Child , DNA, Viral/isolation & purification , Hepatitis B e Antigens/blood , Hepatitis B, Chronic/blood , Humans , Liver/virology , Male , Molecular Sequence Data , Polymerase Chain Reaction , Sequence Analysis, DNA , Transcription Factors/metabolism , Virus Activation , Virus Integration
20.
Hepatology ; 29(4): 1252-8, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10094972

ABSTRACT

The involvement of precore stop codon 1896-A and base exchanges in the AT-rich region at positions 1762 and 1764 of the hepatitis B core promotor has been controversely discussed in adults with fulminant hepatitis B. Because no data are currently available on children, we analyzed the basic core promotor (BCP) and precore region in children with chronic and fulminant hepatitis B. The BCP and precore region were sequenced directly and after cloning from mothers and infants. Thirteen children suffered from chronic liver disease, 6 of whom were treated with interferon alfa (IFN-alpha). All 13 patients seroconverted from hepatitis B e antigen (HBeAg) to hepatitis B e antigen antibodies (anti-HBe), and sera were analyzed before and after seroconversion. Nine vertically infected infants developed a fulminant course of hepatitis B. The occurrence of BCP (1762-T/1764-A, 7.7%) and precore (1896-A, 7.7%; 1899-A, 15%) mutations in chronic hepatitis B was rare. A genotype shift from D to A was observed in 3 patients after development of anti-HBe. A high number of base exchanges was detected in those infants with fulminant hepatitis B. Eight of nine showed a G-A exchange at positions 1896/97 (89%), 1899 (56%), and/or mutations at nucleotide (nt) positions 1762 (56%) and 1764 (78%). All virus strains belonged to genotype D, whereas in the only surviving infant, a D-to-A shift was detected. Hepatitis B virus (HBV) DNA clones were examined from 3 babies and 5 mothers. Our results showed a heterogeneous virus population in 4 of 5 mothers. In contrast, a homogeneous virus population emerged in the infants. According to our data, the analysis in children with fulminant and chronic hepatitis B revealed a striking presence of BCP and precore mutants in infants with fulminant hepatitis (FH) when compared with clinically inapparent anti-HBe-positive children (P <.002), which could be one factor in the pathogenesis of fulminant hepatitis B in children.


Subject(s)
Hepatitis B Core Antigens/genetics , Hepatitis B virus/genetics , Hepatitis B/genetics , Mutation , Promoter Regions, Genetic , Acute Disease , Adolescent , Adult , Child , Child, Preschool , DNA Mutational Analysis , Female , Hepatitis B/blood , Hepatitis B/transmission , Hepatitis B Core Antigens/blood , Hepatitis B Core Antigens/immunology , Hepatitis B virus/immunology , Hepatitis B, Chronic/blood , Hepatitis B, Chronic/genetics , Humans , Infant , Infant, Newborn , Infectious Disease Transmission, Vertical , Male , Mothers , Selection, Genetic
SELECTION OF CITATIONS
SEARCH DETAIL
...