Necrotic cell death in human amniotic cells infected by Listeria monocytogenes.

Listeria monocytogenes can cause a placental-foetal infection that results in spontaneous abortion, premature labour, stillbirth, or neonatal sepsis and meningitis. Bacteria cross the maternofoetal barrier at the villous syncytiotrophoblast level and subsequently spread from the placenta to the fetus. L. monocytogenes is able to induce different kinds of death in a variety of cells. Murine hepatocytes, murine T and human B lymphocytes, and murine dendritic cells die by apoptosis, whereas bacterial infection of murine and human macrophages leads mainly to necrotic cell death. As we previously described the efficient infection and growth of L. monocytogenes in a human amniotic cell line, we investigated the fate of these cells in order to analyse the mode of cell death. Our results provide biochemical and morphological evidence of necrotic death induced by L. monocytogenes infection.

Virulence traits in Escherichia coli strains isolated from outpatients with urinary tract infections.

This study aims to characterize phenotypic and genotypic virulence traits in Escherichia coli strains, isolated from outpatients with urinary tract infections, comparing with those obtained from inpatients. Information on the pathogenic behavior of the uropathogenic strains was obtained by monitoring different biological properties, such as autoagglutination, hemagglutination, adhesiveness to and invasion of human bladder (HT1376) cells, biofilm formation, phylogenetic grouping, and virulence-related genes. The results show similar behavior in the two groups concerning autoagglutination, hemagglutination, and biofilm formation. None of the strains examined was invasive. However, in strains from outpatients there was an increased adhesion to HT1376 cells compared with clinical strains, a significant higher presence of genes codifying for adhesins and cell protection factors, and a lower proportion of strains belonging to B1 group. These findings add further information on the pathogenic traits of community E. coli, since strains isolated from the outpatients' group were differently "armed" in comparison with those of clinical cases, and more suitable to infect healthy individuals.

Invasive pathway of Listeria ivanovii in human amnion-derived WISH cells.

Among Listeria genus, only two species, Listeria ivanovii and Listeria monocytogenes, are pathogenic. L. ivanovii is almost only associated with infections in animals, mainly sheep and cattle, and has rarely been associated with human infections, whereas L. monocytogenes causes severe illnesses in both humans and animals. To further investigate the pathogenetic features of L. ivanovii in humans, we undertook a study in which the intracellular behaviour of this pathogen was analysed in WISH cells, a cell line derived from human amniotic tissue, and compared to that of L. monocytogenes. Using microbiological, biochemical, and ultrastructural approaches, we demonstrate that L. ivanovii can adhere to and invade human amniotic cells, lyse the phagosomal membrane, polymerize host cell actin, and spread from cell to cell more efficiently than L. monocytogenes. However, although L. ivanovii is capable of specifically infecting and replicating in human amnion cells, its survival in cytoplasm is limited compared to that of L. monocytogenes.

Effect of neck flexor muscle activation on impact velocity of the head during backward falls in young adults.

Falls are a common cause of traumatic brain injuries (TBI) across the lifespan. A proposed but untested hypothesis is that neck muscle activation influences impact severity and risk for TBI during a fall. We conducted backward falling experiments to test whether activation of the neck flexor muscles facilitates the avoidance of head impact, and reduces impact velocity if the head contacts the ground. Young adults (n=8) fell from standing onto a 30cm thick gymnastics mat while wearing a helmet. Participants were instructed to fall backward and (a) prevent their head from impacting the mat ("no head impact" trials); (b) allow their head to impact the mat, but with minimal impact severity ("soft impact" trials); and (c) allow their head to impact the mat, while inhibiting efforts to reduce impact severity ("hard impact" trials). Trial type associated with peak magnitude of electromyographic activity of the sternocleidomastoid (SCM) muscles (p<0.017), and with the vertical and horizontal velocity of the head at impact (p<0.001). Peak SCM activations, expressed as percent maximal voluntary isometric contraction (%MVIC), averaged 75.3, 67.5, and 44.5%MVIC in "no head impact", "soft impact", and "hard impact" trials, respectively. When compared to "soft impact" trials, vertical impact velocities in "hard impact" trials averaged 87% greater (3.23 versus 1.73m/s) and horizontal velocities averaged 83% greater (2.74 versus 1.50m/s). For every 10% increase in SCM %MVIC, vertical impact velocity decreased 0.24m/s and horizontal velocity decreased 0.22m/s. We conclude that SCM activation contributes to the prevention and modulation of head impact severity during backward falls.

Phytochemical, Antioxidant and Anticancer Activities of Extracts of Seven Fruits Found in the Southern Brazilian Flora.

Methanol extracts of seven edible fruits found in southern Brazil: Garcinia achachairu, Rubus imperialis, Rubus rosaefolius, Solanum quitoense, Solanum sessiliflorun, Diospyros inconstans and Plinia glomerata, were evaluated for their total phenol content and antioxidant activity in different in vitro free radical scavenging models. In addition, studies were performed on cell viability of extracts of the seeds of G. achachairu against murine melanoma cells. The fruits peel and seeds of G. achachairu were very promising in terms of total phenol content (data in gallic acid equivalent per gram), as assessed by the Folin-Ciocalteu method, with values of 9.70±3.2 and 8.40±1.1, respectively. On the other hand, antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl scavenging assay showed that the fruit pulp and peel of P. glomerata presented the best profile, with values of the 16.3±1.8 and 15.9±2.4 µg/ml, respectively. Regarding the cytotoxic effect of methanol extract and guttiferone A from G. achachairu, we have observed that both inhibit the growth of B16F10 tumor cells, with calculated IC50 values of 49.6±2.1 mg/ml and 48.6±5.4 mM, respectively.

Analysis of the chaotic component of the sinusal R-R intervals as a tool for detecting a silent cardiac dysautonomia in type 2 diabetes mellitus.

This study explores the heart rate (HR) variability (V) in order to detect whether the chaotic component of the sinusal R-R intervals (SRRI) can be interpreted as an early indicator of a silent cardiac neurovegetative dysautonomia in apparently uncomplicated Type 2 diabetic patients (DP). The SRRI were provided by the 24-h Holter ECG of 10 Type 2 DP (5 M and 5 F, mean age = 41 +/- 5 years). Control data were obtained by the 24-h Holter ECG of 10 clinically healthy subjects (CHS, 5 M and 5 F, mean age = 38 +/- 6 years). The chaotic component of HRV was investigated via the correlation dimension (CD) analysis (A) of the SRRI, performed per each hour of the ECG recording. The hourly-qualified series of SRRI, HR and CD index (I) were, in turn, analyzed via methods of conventional statistics and chronobiology, the latter ones for assessing the circadian rhythm (CR). The CDI CR was found to peak during the night in CHS, and to be unphysiologically rotated to the diurnal hours of the day in Type 2 DP. The diurnal inversion of the CDI CR in Type 2 DP suggests that the chaotic component of HRV shows an abnormal rhythnic pattern over the day-night period. Considering that the investigated Type 2 DP were lacking of documentable signs of cardiac neuropathy, it is hypothesized that the diurnal phase of shift CDI CR might be a potential indicator of a silent autonomic cardiac dysfunction in Type 2 DP. Such a hypothesis waits for further confirmations.

HIV-related severe thrombocytopenia in intravenous drug users: prevalence, response to therapy in a medium-term follow-up, and pathogenetic evaluation.

Severe thrombocytopenia (TP) accounted for 5.3% of cases in a consecutive series of 380 HIV-infected intravenous drug users (IVDUs) at presentation. Forty-one of 53 subjects with severe TP showed haemorrhages and were treated as follows: ten were splenectomized, 17 were given high-dose intravenous immunoglobulins (HDIg), and 10 received anti-Rh(D) immunoglobulins (anti-Rh Ig). Splenectomy induced a complete clinical response in all cases: four out of 10 patients maintained platelet counts greater than 100 x 10(9)/l. HDlg gave a good clinical response in all patients, but eight out of 17 suffered haemorrhages during the follow-up and recall treatments were necessary. Six out of 10 patients treated with anti-Rh lg maintained platelet counts greater than 30 x 10(9)/l, but in two cases the treatment was interrupted because of severe haemolysis. No patient progressed to overt AIDS during the follow-up. Splenectomized patients in particular did not show adjunctive risks of worsening of the HIV-related clinical picture. A platelet kinetic study performed in 20 patients with severe HIV-related TP suggests a possible role for platelet sequestration in TP of HIV-infected IVDUs, in which a liver involvement is very frequent.

Community-acquired bacteremias from tunneled central intravenous lines: results from studies of a single vendor.

Tunneled central intravenous catheters are a common method for rendering prolonged outpatient intravenous therapy. Their safety, however, has not been well studied. We conducted a retrospective evaluation of bacteremias associated with tunneled central intravenous catheters managed by a single home health care vendor during a 1-year period. All catheters were inserted in the operating room under sterile conditions. To calculate total line days, the dates of catheter insertion and removal were obtained from either the hospital operating room or the home health care agency. Catheter care was conducted according to written protocols. Total line days were calculated. Community-acquired bacteremia (defined as bacteremia occurring more than 6 days after the patients' discharge from the hospital) was determined from records available in the infection control department. Sixty-eight patients received intravenous therapy from the vendor during the 1-year study period. Total line days were 5548 (median 52 days/patient). Eleven episodes of bacteremia occurred in five patients, providing an incidence density rate of 2.0 infections/1000 catheter days. The most frequent bacteria encountered were Staphylococcus epidermidis (five), Klebsiella pneumoniae (two), and Acinetobacter calcoaceticus var anitratus (two). Median time to bacteremia was 103 days. Two patients, both younger than 4 years, accounted for seven of the infections; both had short-bowel syndrome. On the basis of historical comparisons, outpatient intravenous therapy appears to be associated with a lower risk of bacteremia than in-hospital therapy. These data can provide quality improvement information and may be a means for comparing home infusion therapy vendors.

Surgical wound infections documented after hospital discharge.

Shorter lengths of hospitalization may result in more surgical wound infections being documented after hospital discharge. The current investigation analyzed 1644 surgical procedures performed over a 3-month period, and documented surgical wound infections both before and for 1 month after hospital discharge. Physician and patient questionnaires were used. One hundred eight infections were noted, of which 50 (46%) were seen after hospital discharge by either the patient or the surgeon. Rates of infection were 5.2%, 7.5%, and 7.5% for clean, clean-contaminated, and contaminated-dirty categories, respectively. Had postdischarge surveillance not been used, rates would have appeared to be 2.5%, 6.5%, and 6.8% for the same surgical classes. Infections following clean and clean-contaminated procedures were more likely to be noticed after hospital discharge. Excluding those that were patient-documented, wound infection rates would have been 4.2% (clean), 6.3% (clean-contaminated) and 6.8% (contaminated-dirty). Postdischarge surveillance is imperative to meaningfully document true rates of surgical wound infection, inasmuch as increasing numbers are likely to occur only after patients leave the hospital.

A case of Vogt-Koyanagi-Harada syndrome in a patient affected by Hodgkin's disease.

The Vogt-Koyanagi-Harada (VKH) syndrome, a disease of unknown origin, characterized by inflammation of the uveal tract, retina and meninges, was observed in a patient with Hodgkin's disease (HD) who had been treated with chemotherapy and radiotherapy. Ten years later the patient developed a cluster of neurological symptoms and signs (fever, pain, bilateral hypoacousia, dizziness, uveitis and psychiatric disorder) which were initially interpreted as a relapse of HD. The diagnosis of VKH syndrome was thereafter suspected from the clinical findings, response to therapy and further evolution. During the follow-up (14 months) the patient showed a varying course; hypoacousia remained unaltered while uveitis recurred and only a partial improvement was obtained by immunosuppressive therapy.

Backward walking at three levels of treadmill inclination: an electromyographic and kinematic analysis.

Backward walking on a treadmill is a common tool for lower extremity rehabilitation in the clinical setting. The purpose of this study was to evaluate the adaptations in the gait cycle produced by walking backward on a treadmill at 0, 5, and 10% inclination. Sixteen healthy adult subjects (14 females, two males), mean age of 23.19 +/- 3.02, participated. Joint positions for hip, knee, and ankle were measured during a complete gait cycle. Values were time matched with average electromyographic (EMG) activity (surface electrode) of the rectus femoris, hamstrings, gastrocnemius, and anterior tibialis during each subphase of gait (initial contact, midstance, heel-off, and midswing). Values of joint position and average EMG were compared over the three treadmill conditions. Subjects walked for approximately 1 minute at 4.0 km/h. A simple repeated measures analysis of variance (p < .05) with a Duncan post hoc test was used to analyze for changes. Significant changes occurred in the joint positions of the knee and ankle at initial contact (ankle increased from 9.81 +/- 5.06 degrees to 13.08 +/- 3.68 degrees; knee increased from 30.94 +/- 5.25 degrees to 42.42 +/- 4.08 degrees) as the treadmill was raised from 0 to 10%. Significant changes occurred for average EMG activity for each muscle studied over the three treadmill conditions. The greatest changes occurred in the gastrocnemius at initial contact (increase from 189.76 +/- 44.29% to 293.09 +/- 79.16%) between the 0 and 10% conditions. The results of this investigation confirm that backward walking up an incline may place additional muscular demands on an individual.(ABSTRACT TRUNCATED AT 250 WORDS)

The test-retest reliability of an inclined squat strength test protocol.

Functional testing of the lower extremity is supported as a good predictor for successful return to premorbid activity. However, current reliable functional tests may be too strenuous for a patient in the acute stage of recovery. A functional testing protocol utilizing an inclined sliding board apparatus was evaluated for test-retest reliability. Thirty-five subjects (ages = 18-25, mean = 20.49 +/- 1.71) with no known knee pathologies were tested. Subjects performed a 20-second test for squat repetitions and a 50-squat repetition test for time, executing a single leg squat in an inclined position on the sliding board apparatus. The test was repeated 1 week later. The intraclass correlation coefficient equaled 0.80 for the 50-repetition timed test and 0.89 for the 20-second repetition test. The results indicate an acceptable test-retest reliability for the inclined sliding board apparatus protocol. We advocate the use of this testing protocol for the purpose of evaluating functional ability during the early stages of rehabilitation of lower extremity conditions.

Triathlon and the multisport athlete.

The sport of triathlon is a rapidly growing arena for athletic competition and training. Men and women of various fitness backgrounds have become involved in this sport that involves the disciplines of swimming, cycling, and running. Training for multiple sports has the advantages of providing the athlete with a variety of means of maintaining fitness in the event of an injury. On the other hand, multisport training may also contribute to a special category of injuries, those related to the cumulative effects of cross-training. The purpose of this paper is to provide a review of the literature regarding triathlon training and injuries. A survey of a local triathlon club regarding the incidence of injuries is presented, and comparisons are made with previously published surveys. Finally, this paper attempts to outline the training conditions of the triathlete and to provide readers with strategies for injury management.

An electromyography study of wrist extension orthoses and upper-extremity function.

OBJECTIVE: This study examined the effect of commonly used long and short styles of commercially produced wrist extension orthoses on the activity of the proximal muscles of the shoulder and elbow and on wrist flexor and extensor muscle activity. METHOD: While 17 women between 22 and 40 years of age (M = 26.6) performed a specified movement wearing each of the two styles of orthosis and without an orthosis, their motor unit recruitment of five proximal joint muscle groups, wrist extensors, and wrist flexors was measured by surface electromyography. RESULTS: Motor unit recruitment was significantly greater in both orthosis conditions for four of five proximal muscles and for wrist flexors. There were no significant differences between the short and long orthosis conditions for proximal muscle groups. CONCLUSION: Wearing a wrist extension orthosis appears to place additional stress on the proximal joint musculature beyond that found without splint use. The study has implications for the prescription of wrist extension orthoses, especially for patients whose proximal joints are already compromised.

[Circadian periodicity in human heart rate daily variability disorders: subsequent demonstrations through a chronobiological approach to the values of estimated alpha exponent on sinusal R-R intervals]. / Periodicità circadiana del disordine nella variabilità giornaliera della frequenza cardiaca umana: ulteriore dimostrazione tramite approccio cronobiologico ai valori dell'esponente alfa stimato sugli intervalli sinusali R-R.

OBJECTIVE: The present study is aimed at giving a further demonstration that the disorder in human heart rate variability is characterized by a circadian periodicity. Such an evidence has been provided by estimating the alpha exponent of the Lévy's stable distribution approximated to the histogram of the differences between the durations of two adjacent sinusal R-R intervals. MATERIALS AND METHODS: The purpose has been pursued by estimating the alpha exponent on fragments of one hour of the Holter electrocardiogram executed in 10 clinically healthy subjects (5 males and 5 females, ranging in age from 23 to 30 years). RESULTS: The chronobiological analysis of the hourly-qualified values of the alpha exponent has demonstrated a significant circadian rhythm for this coefficient. CONCLUSIONS: The significant circadian periodicity of the alpha exponent is a further evidence that the disorder in human heart rate variability, herein represented by the extreme variability of the differences between the durations of two consecutive sinusal R-R intervals, is characterized by a periodic recursivity.

Stability and change in personality across the life span: behavioral-genetic versus evolutionary approaches.

Recent findings and theoretical models of behavioral-genetic and evolutionary approaches to personality development across the life span are presented. Theoretical and empirical strengths and weaknesses of these approaches regarding the issue of stability and change are outlined. Although these "biological" models may appear disparate as often as they appear similar, they share the common assumption that most personality phenomena are products of environmental contingencies. However, they differ with regard to the level at which they analyze and incorporate environmental influences into their interpretations of stability and change. Genetic influences are also examined. A theoretical integration of the recent findings and of the models of genetic and environmental influences on personality via evolutionary and behavioral-genetic approaches is intended to fill in the gaps and stimulate research on the study of personality development across the life span.