Response of cartilaginous neoplasms of the larynx to surgery and alternative therapies

Three primary cartilaginous tumors of the larynx are reported: two chondrosarcomas (including an undifferentiated chondrosarcoma with prolonged survival) and one chondroma. The need for accurate histological staging, only possible after surgery, is emphasized. Surgery is teh preferred initial treatment.     

C1-esterase inhibitor prevents early pulmonary dysfunction after lung transplantation in the dog

The success of lung transplantation to a large extent depends on effective protection of the graft from ischemic injury after reperfusion. Although mechanisms have not been clarified, the pathologic findings of ischemic injury after reperfusion are similar to adult respiratory distress syndrome, a condition in which the blood coagulation contact system is activated. This study evaluates the effect of C1-esterase inhibitor (C1-INH), the main inhibitor of the blood coagulation contact system, on short-term lung function in a dog model of orthotopic lung transplantation. Twelve lung transplantations were performed after 24 h of ischemic time. Dogs were randomly assigned to receive either vehicle (Control) or C1-INH. After the lung transplantation in the control group, Pao2 decreased by 84% and both the AaPO2 and the Qs/Qt% increased (340 and 530%, respectively, p < 0.01); these parameters remained unchanged in the C1-INH group. The hypoxemia observed in control animals was associated with decreased blood coagulation contact factors, complement consumption, increased expression of adhesion glycoproteins in leukocytes, and extensive intraalveolar and interstitial neutrophil infiltration. In contrast, C1-INH administration prevented hypoxemia, the decrease in blood coagulation contact factors, the activation of the complement system, the increase in expression of leukocyte adhesion molecules, and inflammatory cell infiltrate. This study has demonstrated that in a dog model of lung transplantation, the administration of C1-INH prevents early pulmonary dysfunction, and it suggests that activation of blood coagulation contact system and complement are important mechanisms causing ischemic injury after reperfusion.     

Urinary retinol excretion and kidney function in children with shigellosis

BACKGROUND: Acute infections, including diarrhea, are associated with an increased risk of vitamin A deficiency. Urinary retinol excretion during such infections may contribute to this risk. The mechanism accounting for urinary retinol loss has not been clearly defined. OBJECTIVE: This study attempted to determine whether urinary retinol loss in children with acute infection is associated with impaired kidney function, particularly impaired tubular protein reabsorption. DESIGN: Urinary retinol excretion and kidney function were examined in 66 hospitalized children 5 mo to 5 y of age with acute Shigella dysentery. RESULTS: Urinary retinol loss occurred in 59% of children and was substantial (>0.1 micromol/d) in 8% of them. Children with more severe disease excreted higher concentrations of urinary retinol; those with a body temperature > or =40 degrees C excreted a mean of 0.10 +/- 0.18 micromol/d compared with 0.005 +/- 0.008 micromol/d for other children (P < 0.0001). Children with more severe disease also had impaired tubular reabsorption of low-molecular-weight proteins beta2-microglobulin and retinol binding protein (RBP)], although other measures of tubular and glomerular function were not similarly impaired. In multiple regression analysis, severity of disease indicators were the best predictors of tubular reabsorption of beta2-microglobulin (R2 = 0.53) whereas tubular reabsorption of beta2-microglobulin and RBP were found to be the best predictors of urinary retinol loss (R2 = 0.69). CONCLUSIONS: A significant amount of retinol was excreted in the urine in children with shigellosis: 8% excreted >0.10 micromol/d (15% of the daily metabolic requirement). Impaired tubular reabsorption of low-molecular-weight proteins, such as RBP transporting retinol, appeared to be the cause of this urinary retinol loss.     

Long-term treatment of bleeding caused by portal hypertension in children

We have compared the hypnotic requirements for i.v. thiopentone alone and in combination with i.m. lignocaine or bupivacaine. Ninety women, ASA I-II, undergoing minor gynaecological surgery were allocated randomly to nine groups of 10 patients to receive thiopentone combined with i.m. lignocaine, bupivacaine or saline, respectively. Thiopentone was administered in bolus doses of 0.5 mg kg-1 every 30 s until loss of response to verbal command. Lignocaine and bupivacaine significantly enhanced the hypnotic effect of thiopentone in a dose-dependent manner. The maximum doses tested (lignocaine 3.0 mg kg-1 and bupivacaine 1.0 mg kg-1) reduced the hypnotic dose of thiopentone by 39% and 48%, respectively. We conclude that if lignocaine or bupivacaine are injected into soft tissue before induction of anaesthesia by thiopentone, the i.v. dose of the latter should be modified accordingly.     

Complex dynamics in classical control systems

An analysis of the complex dynamical behavior of second-order linear plants controlled with conventional controllers is presented. The control signal is passed through a classical nonlinearity before being applied to the plant. Existence of periodic and homoclinic orbits is discussed. Using the Melnikov/Smale and Genesio/Tesi methods some conditions about the existence of invariant strange sets are also established. It is shown that simple classical control schemes with typical nonlinearities can exhibit chaotic dynamics in a certain range of the controller parameters. Numerical and experimental results support the analysis presented.     

Detection of antibodies to Candida albicans germ tubes for diagnosis and therapeutic monitoring of invasive candidiasis in patients with hematologic malignancies

We prospectively investigated the ability of detection of antibodies to Candida albicans germ tubes (CAGT) to diagnose invasive candidiasis in 95 consecutive admissions of 73 patients with hematologic disorders undergoing intensive chemotherapy. The episodes were divided into three groups according to clinical and microbiological diagnosis. Group 1 comprised eight admissions of eight patients with invasive candidiasis. Group 2 comprised 42 admissions of 34 patients without evidence of invasive candidiasis. Group 3 comprised the remaining 45 admissions of 37 patients with febrile episodes which were not diagnosed by microbiological culture. Antibodies to CAGT were detected in 87.5% of group 1 patients. Detection of antibodies to CAGT in patients with Candida fungemia was delayed somewhat relative to the time the blood culture was positive, but antibodies to CAGT were detected earlier than a diagnosis was made in patients with deep-tissue candidiasis. Sera from 2 admissions in group 2 and 12 admissions in group 3 revealed antibodies to CAGT. At a titer of > or = 1:20, detection of antibodies to CAGT had a sensitivity of 87.5%, specificity of 95.2%, positive predictive value of 77.8%, and negative predictive value of 97.6%. Antibodies to CAGT were usually detected before beginning of empiric antifungal therapy. Titers of antibodies to CAGT were maintained in most patients who died but declined and eventually disappeared in the patients who survived. Since antibodies to CAGT were detected in all patients with tissue-proven invasive candidiasis but negative by blood culture, detection of antibodies to CAGT complemented blood cultures for diagnosis and therapeutic monitoring of patients with hematologic malignancies and invasive candidiasis.     

Successful treatment of orbital rhabdomyosarcoma in two infants using chemotherapy alone

In a prospective study, arthroscopic examinations were performed on 42 wrists following injury. Clinical findings, radiology, and arthrography were compared to the arthroscopic findings. Only obvious or total ligamentous ruptures found on arthroscopy were considered in the analysis. No direct correlation could be demonstrated with clinical findings or arthrography. The distribution pattern of ligament injury involving the radial and ulnar compartment of the wrist joint in 40% of the cases suggests that carpal dysfunction following injury and ligamentous tears is a more complex problem than usually accepted. The ulnar midcarpal joint seems more prone to injury than the radiocarpal portion of the wrist. This suggests an important biomechanical function of the palmar ligaments inserting on the triquetrum.