Sputum cytokine levels in patients with pulmonary tuberculosis as early markers of mycobacterial clearance

Sputum and serum from patients with active pulmonary tuberculosis (TB), healthy purified protein derivative-positive adults, and patients with bacterial pneumonia were collected to simultaneously assess local immunity in the lungs and peripheral blood. To determine whether cytokine profiles in sputum from TB patients and control subjects were a reflection of its cellular composition, cytospin slides were prepared in parallel and assessed for the presence of relative proportions of epithelial cells, neutrophils, macrophages, and T cells. Gamma interferon (IFN-gamma) in sputum from TB patients was markedly elevated over levels for both control groups. With anti-TB therapy, IFN-gamma levels in sputum from TB patients decreased rapidly and by week 4 of treatment were comparable to those in sputum from controls. Further, IFN-gamma levels in sputum closely followed mycobacterial clearance. Although detected at fourfold-lower levels, IFN-gamma immunoreactivities in serum followed kinetics in sputum. TNF-alpha, interleukin 8 (IL-8) and IL-6 also were readily detected in sputum from TB patients at baseline and responded to anti-TB therapy. In contrast to IFN-gamma, however, TNF-alpha and IL-8 levels also were elevated in sputum from pneumonia controls. These data indicate that sputum cytokines correlate with disease activity during active TB of the lung and may serve as potential early markers for sputum conversion and response to anti-TB therapy.     

Nonpeptide antagonists of AT1 receptor for angiotensin II delay the onset of acute respiratory distress syndrome

We have previously reported that losartan, a selective antagonist of AT1 receptors for angiotensin II (AII), strongly suppresses the activation of neutrophils by N-formylmethionyl-leucyl-phenylalanine (fMLP) through a mechanism that does not involve inhibition of AT1 receptors. Herein, we analyze whether losartan would prevent the development of the acute respiratory distress syndrome (ARDS) triggered by lung bacterial infection. We found that losartan (0.2-200 microg/kg/min) delays the onset of ARDS in Wistar rats challenged by i.t. instillation of Bordetella bronchiseptica. Although this effect was associated with a significant inhibition of lung-neutrophil recruitment, lung bacterial clearance was not impaired but rather, it was significantly improved. We also found that another nonpeptide AT1 receptor blocker, irbesartan, exerted similar effects to losartan, i.e., it was also able to inhibit neutrophil activation by fMLP and to delay the onset of ARDS in B. bronchiseptica-challenged rats. Neither the inhibitor of angiotensin-converting enzyme captopril, nor the nonselective peptide inhibitor of AII receptors saralasin reproduced these effects. Our data are consistent with the possibility that nonpeptide AT1 receptor blockers delay the onset of ARDS triggered by bacterial infection through a mechanism dependent, at least in part, on their ability to prevent neutrophil activation by N-formyl-peptides.     

Reasons for discontinuing intravenous therapy associated with the time of in-situ permanence of peripheral venous devices

This study aimed to relate the reasons for interrupting intravenous therapy and the time of in-situ permanence of venous devices. The results obtained showed that in 38 of the 75 punctures performed, the reason to interrupt the venous therapy took place after the end of the therapy and that time of in-situ permanence of peripheral devices varied from 24 to 48 hours. In 15 punctures, in which infiltration was the reason for interruption, the time of permanence was shorter than 24 hours. It is believed that the data gathered in this investigation should be analyzed by nursing professionals, aiming to enhance new educational programs in services related to intravenous therapy.     

Instant centre frequency at anaesthetic induction--a new way to analyse sympathovagal balance

The instant centre frequency (ICF) of RR interval has been proposed as a global index to analyse the sympathovagal interaction in the heart. The aim of this study was to assess the ICF during anaesthesia to test if it can reliably capture the neural control of the cardiovascular system. Twenty-four ASA II or III patients scheduled for cardiac surgery were included in the study. They were allocated in two groups: control, no treatment (group 1, n = 12), and beta-adrenergic blockade by atenolol (group 2, n = 12). Spectra of pulse interval series were computed with a time-frequency method and they were divided into: very low frequency (VLF, 0.000-0.040 Hz), low frequency (LF, 0.050-0.150 Hz) and high frequency (HF, 0.160-0.500 Hz). Normalized power was obtained by dividing the cumulative power within each frequency band (LF or HF) by the sum of LF and HF; the ratio of LF/HF was also calculated. Instant centre frequency is a time-varying parameter that the evolution along time of the gravity centrum of a local spectrum. All spectral indexes were recorded at the following time points: before induction, after induction and before intubation, during intubation, and after intubation. The atenolol group had lower normalized LF and the LF/HF ratio (P < 0.05) higher HF before induction; and lower LF/HF ratio after induction and before intubation (P < 0.05). The ICF was higher in atenolol group at all times. The ICF shifted towards HF frequency after induction and before intubation and shifted towards LF during intubation in both groups. The autonomic nervous system control on the heart through the interaction of sympathetic and parasympathetic reflex mechanisms could be studied by the ICF. The ICF may assess the autonomic cardiac modulation and may provide useful information for anaesthetic management.     

Virulent Mycobacterium fortuitum restricts NO production by a gamma interferon-activated J774 cell line and phagosome-lysosome fusion

The virulence of different isolates of Mycobacterium has been associated with two morphologically distinguishable colonial variants: opaque (SmOp) and transparent (SmTr). In this report we used an in vitro assay to compare macrophage (Mphi) responses to SmOp and SmTr Mycobacterium fortuitum variants, taking advantage of the fact that these variants were derived from the same isolate. Cells preactivated or not with gamma interferon (IFN-gamma) were infected with SmOp or SmTr M. fortuitum. We showed that SmOp and SmTr induced different levels of nitric oxide (NO) production by IFN-gamma-stimulated Mphi. Indeed, the amount of IFN-gamma-induced NO production by J774 cells was 4.8 to 9.0 times higher by SmOp (23.1 to 37.7 micro M) compared to SmTr infection (3.9 to 4.8 micro M) (P = 0.0332), indicating that virulent SmTr bacilli restricted NO production. In addition, IFN-gamma-induced NO production by Mphi was higher when correlated with reduction of only avirulent SmOp bacillus viability. SNAP (S-nitroso-N-acetyl-DL-penicillamine)-induced NO production did not modify SmTr viability, indicating its resistance to nitrogen radicals. Electron microscopy studies were performed to evaluate the capacity of phagosomes to fuse with lysosomes labeled with bovine serum albumin-colloidal gold particles. By 24 h postinfection, 69% more phagosome-containing SmOp variant had fused with lysosomes compared to the SmTr-induced phagosomes. In conclusion, these data indicate that virulent SmTr bacilli may escape host defense by restricting IFN-gamma-induced NO production, resisting nitrogen toxic radicals, and limiting phagosome fusion with lysosomes.     

ThermoSpot in the detection of neonatal hypothermia

Thermal care is a critical part of caring for neonates. The need to identify simple, affordable and effective tools for detecting hypothermia in newborn infants that can be used by mothers and other caregivers in resource-poor countries remains crucial in our efforts to reduce perinatal and neonatal mortality and morbidity. The objective of this study was to determine the effectiveness of ThermoSpot in detecting hypothermia in newborn infants in a developing country. The prevalence of hypothermia (< 36 degrees C) in our study population was 51.4%. The ThermoSpot disc indicated green (normothermia) in 82% of infants whose axillary temperature was between 32 and 35.9 degrees C. However, the disc had a 100% specificity and positive predictive value at body temperatures below 36 degrees C and axillary temperatures below 36 degrees C or above 37.5 degrees C. Sensitivity, negative predictive value and accuracy were 19%, 52% and 57%, respectively. Mortality was significant in infants with black or blue ThermoSpot disc colours compared with green. For ThermoSpot discs placed on the abdomen, the risk of dying was 2.67 times higher if the disc colour was black compared with green and 2.43 times higher if the disc colour was blue compared with green. Similarly for ThermoSpot discs placed in the axilla, the risk of dying was 2.54 times higher if the disc colour was black and 2.5 times higher if the disc colour was blue as opposed to green. There is a need to improve the sensitivity and accuracy of ThermoSpot in detecting hypothermia before its widespread use.     

Msx1 is a regulator of bone formation during development and postnatal growth: in vivo investigations in a transgenic mouse model

The present study is devoted to Msx1 distribution and function from birth to 15 months, events and periods still unexplored in vivo using Msx1 knock in transgenic mice. The study is focused on the mandible, as an exemplary model system for Msx1-dependent neural crest-derived skeletal unit. The transgenic line enabled study of morphological abnormalities in Msx1 null mutation mice and Msx1 protein expression in Msx1+/- heterozygous mice. In Msx1 null mutation, the most striking feature was an inhibition of the mandibular basal convexity, the absence of teeth and alveolar bone processes, and absence of endochondral ossification in the mandibular condyle. At birth, in Msx1+/- heterozygous animals, we identified for the first time a double Msx1 aboral-oral and disto-proximal gradient field developmental pattern located in the low border of the mandibular bone in relation with this bone segment modeling. Msx1 expression involved both osteoblast and osteoclast cells. A distinct pattern characterized bone surfaces: Periosteum osteoblast differentiation was related to Msx1 down-regulation, while in the endosteum both differentiated osteoblasts and osteoclasts expressed the homeoprotein. In postnatal stages, Msx1 expression was maintained in the alveolar bone processes and dento-alveolar cells in relation with tooth function. Our data suggest that Msx1 play a role in a site-specific manner not only in early patterning but also in skeletal growth and modeling by acting on heterogenous bone cell populations.     

Genetic organisation of <Emphasis Type="Italic">Iris yellow spot virus</Emphasis> M RNA: indications for functional homology between the G<Subscript>(C)</Subscript> glycoproteins of tospoviruses and animal-infecting bunyaviruses

Summary.  The complete nucleotide sequence (4838 nucleotides) of Iris yellow spot virus (IYSV) M RNA indicates, typical for tospoviruses, the presence of two genes in ambisense arrangement. The vRNA ORF codes for the potential cell-to-cell movement (NSm) protein (34.8 kDa) and the vcRNA ORF for the viral glycoprotein (G1/G2) precursor (128.6 kDa). Multiple sequence alignment of the NSm and G1/G2 precursor proteins of IYSV with those of other tospoviruses, showed highest homologies to Peanut bud necrosis virus (PBNV) and Watermelon silver mottle virus (WSMV). The potential cell-to-cell movement protein of tospoviruses is highly conserved (40–70% identity), with the exception of the first 60 N terminal amino acids, a domain that clearly diverged. For the G1 and G2 viral glycoproteins, blast searches revealed a significant homology between the C-terminally located tospoviral G1 (G_(C)) protein with the counterpart of the animal-infecting bunyaviruses, suggesting a functional homology for these proteins. Received January 15, 2002; accepted July 10, 2002