Cerebral superb microvascular imaging in preterm neonates: in vivo evaluation of thalamic, striatal, and extrastriatal angioarchitecture.

PURPOSE: To explore the potential of superb microvascular imaging (SMI) in visualizing brain microvessels in preterm neonates of different gestational ages (GA). METHODS: In this retrospective, observational pilot study, 15 preterm newborns were equally divided into GA groups: extremely (GA < 28 weeks), very (28-31 weeks), and moderate to late (32-37 weeks) preterm. All patients underwent conventional transcranial ultrasounds during the first day of life following the American Institute of Ultrasound in Medicine practice guidelines. SMI was then performed; based on their SMI morphology and location, brain microvessels were classified as extrastriatal (cortical and medullary), striatal, or thalamic. Two examiners independently classified vessels as visible or invisible. To assess the association between vessel visibility and GA, binomial logistic regression analysis (separate for each microvessel group) was performed, taking visibility as a dependent variable and both examiners and GA as predictor variables. RESULTS: A statistically significant difference among GA groups was found in sex (P = 0.030), birth weight (P = 0.007), and Apgar score within 1 min after birth (P = 0.024). Microvascular visibility increased with GA for superficial vessels (P < 0.05 for both cortical and medullary), while striatal and thalamic vessels were visible in all neonates irrespective of their GA. CONCLUSIONS: SMI technology shows promise to assess brain microvasculature in preterm neonates, even potentially providing data on early brain development.

From chronic overfeeding to hepatic injury: role of endoplasmic reticulum stress and inflammation.

We analyse how chronic overfeeding, by increasing circulating fatty acids, might lead to inflammation, insulin resistance (IR) and injury in the liver. Chronic overfeeding causes an increase in adipose tissue depots and is characterised by an increased presence of hypertrophic adipocytes when adipose tissue expandability is inadequate. Adipocyte hypertrophy is a possible stress condition for the endoplasmic reticulum (ER), which will activate inflammatory and apoptotic pathways and cause IR in adipose tissue. Insulin-resistant adipocytes, being more lipolytic and less liposynthetic, induce an increase in circulating free fatty acids. Moreover, the strongly compromised secretion/function of the adipocyte hormones, adiponectin and leptin, decreases lipid oxidation, particularly in the liver, causing lipid accumulation, ER stress and IR in hepatocytes. ER stress may lead to reduced very-low-density lipoprotein (VLDL) secretion and increased lipogenic gene expression despite the presence of IR. These events and reduced lipid oxidation may lead to further hepatic lipid accumulation. When the triglyceride storage capacity of hepatocytes is exceeded, hepatic injury may occur. ER-stressed steatotic hepatocytes activate apoptotic and inflammatory pathways, which trigger IR and the release of chemokines and cytokines, and these, in turn, elicit an increased influx of Kupffer cells (KCs) and hepatic stellate cells (HSCs) around dying hepatocytes. Soluble mediators, secreted mainly by ER-stressed steatotic hepatocytes and activated KCs, induce the transdifferentiation of HSCs to myofibroblasts, which secrete fibrogenic cytokines and matrix components that trigger fibrosis. In conclusion, chronic lipid overloading due to inadequate fat-storing capacity of adipose tissue can induce hepatic injury when triglyceride storage capacity of hepatocytes is exceeded.

From chronic overnutrition to insulin resistance: the role of fat-storing capacity and inflammation.

AIMS: We analyze how the inflammatory state in adipose tissue caused by a condition of chronically positive energy balance can lead to insulin resistance first in adipose tissue, then in all insulin-sensitive tissues. DATA SYNTHESIS: Chronic nutrient overload causes an increase in adipose depots that, if adipose tissue expandability is low, are characterized by an increased presence of hypertrophic adipocytes. This adipocyte hypertrophy is a possible stress condition for the endoplasmic reticulum (ER) that would lead to a proinflammatory state in adipose tissue. In this condition, ER stress would activate metabolic pathways that trigger insulin resistance, release of macrophage chemoattractant proteins, and in chronic inflammation, the death of the hypertrophic adipocyte. The infiltrated macrophages in turn release inflammatory proteins causing further recruitment of macrophages to adipose tissue and the release of inflammatory cytokines. Following these events, insulin resistance becomes extended to all adipose tissue. Insulin-resistant adipocytes, characterized by low liposynthetic capacity and high lipolytic capacity, cause increased release of free fatty acids (FFA). FFA released by lipolitic adipocytes may also activate Toll-like receptors 4 and then chemokines and cytokines release amplifying insulin resistance, lipolysis and inflammation in all adipose tissue. Moreover, increased circulating FFA levels, reduced circulating adiponectin levels and leptin resistance lead to decreased lipid oxidation in non-adipose tissues, thereby triggering ectopic accumulation of lipids, lipotoxicity and insulin resistance. CONCLUSION: All the conditions that increase circulating fatty acids and cause lipid overloading (obesity, lipoatrophy, lipodystrophy, catabolic states, etc.) induce a lipotoxic state in non-adipose tissues that gives rise to insulin resistance.

De novo autoimmune hepatitis following liver transplantation: a case report.

De novo autoimmune hepatitis (AIH), a rare disorder first described in 1998, appears in patients with liver transplants due to autoimmune and nonautoimmune etiologies. De novo AIH occurs in 2.5% to 3.4% of allografts; children seem to have a predilection for this syndrome. We have present herein a case of a liver allograft recipient who developed chronic hepatitis associated with autoimmune features outlining the clinical course, liver histology, and response to treatment.

The Horton-Rogers-Lapwood problem for an inclined porous layer with permeable boundaries.

A formulation of the Horton-Rogers-Lapwood problem for a porous layer inclined with respect to the horizontal and characterized by permeable (isobaric) boundary conditions is presented. This formulation allows one to recover the results reported in the literature for the limiting cases of horizontal and vertical layer. It is shown that a threshold inclination angle exists which yields an upper bound to a parametric domain where the critical wavenumber is zero. Within this domain, the critical Darcy-Rayleigh number can be determined analytically. The stability analysis is performed for linear perturbations. The solution is found numerically, for the inclination angles above the threshold, by employing a Runge-Kutta method coupled with the shooting method.

Infectious complications in the renal transplant recipient.

The aim of this study was to estimate the incidence of infectious diseases in a group of patients who underwent kidney transplantation from January 1, 2004 to September 30, 2004, including 121 operations, with 119 from cadaveric and 2 from living donors. The protocol sought herpes viruses (CMV, VZV, and EBV), hepatitis viruses, human immunodeficiency virus, T. gondii, M. tubercolosis, and T. pallidum. Therapy for CMV was used both as prophylaxis in immunoglobulin (Ig)G-negative recipients from IgG-positive donors and preemptive therapy, that is, before the appearance of clinical symptoms, but after viremia reached borderline levels. For VZV infections, the treatment started after the appearance of papulo-vesicular cutaneous eruptions and antibody positivity. The treatment for pneumonia consisted of empirical therapy after radiography; for pyelonephritis, antibiotic therapy was based on the results of kidney echography, blood culture, and urine culture. Infectious complications appeared in 25 patients (20.7%), 3 of the which were polymicrobic: 12 CMV infections, 9 VZV infections, 3 pneumoniae, 4 pyelonephritis, and 1 salmonellosis. The most frequent infection was CMV, which occurred in the first 3 months after transplantation in 9 of 12 cases. This study showed that a knowledge of infection prevalence can help the physician to establish a more specific, efficacious antimicrobial therapy, despite the laboratory response not being available in a short time.

Urologic complications in kidney transplantation.

Urologic complications in kidney transplantation have an incidence ranging from 3% to 20%, representing an important cause of organ loss. From January 2001 to September 2004, 123 renal transplantations were performed using an immunosuppressive protocol including basiliximab, mycophenolate mofetil, calcineurin inhibitors, and steroids. The surgical technique was vascular anastomoses to external iliac vessels, and ureteral anastomosis according to Lich Gregoire technique using a JJ ureteral stent. We report 5 renal complications (4.2%) and 4 extrarenal complications (3.5%), the majority of which required corrective surgery. The surgical strategy uses the clinical condition of the donor and the recipient; the anatomic anomalies of the graft, and a reduced cold ischemia time. Moreover, a reduction in acute rejection episodes and immediate renal function has been fundamental to reduce urologic complications. In fact, the main cause of urologic complications is ureteral ischemia, linked both to backtable surgery and to rejection episodes. Another important factor in the reduction of early urologic complications has been the routine use of a JJ stent, which allowed us a conservative approach in this setting.

Malignancies after kidney transplantation.

The most effective treatment of end-stage renal disease is renal transplantation; its superiority to prolong the longevity of patients is well established. Patient and graft survivals have improved with more potent immunosuppression but this advance has been associated with an increased incidence of cancer. The aim of this study was to assess the prevalence of cancer among 265 kidney transplant recipients engrafted between 1968 and October 2004. The overall prevalence of de novo malignancies was 3%. The mean age at diagnosis was 53.3 years (range, 28-63 years) and the duration of the transplant was 11.6 years (range, 0.3-33 years). One patient among 127 (0.8%) who had a history of less than 3 years under immunosuppression, developed a posttransplantation lymphoproliferative disorder (PTLD). Among the 138 patients who had more than 3 years immunosuppression, 7 (5%) developed neoplasms of vulva, colon, native kidneys, prostatic gland, and ovary. One patient was affected by de novo carcinoma in the transplanted kidney. Compared with other published studies, our early cancer prevalence is low, possibly due to a careful history before grafting, good HLA matching, and abstinence from anti-T-cell therapy for treatment of acute rejection episodes. The low level of immunosuppression may account for the low prevalence of neoplasia. The risk of developing a malignancy increases with long-term immunosuppression, comparable with most reports.

Rat liver mitochondrial respiratory capacities in the transition from weaning to adulthood.

In the present study we investigated the changes in hepatic mitochondrial function in the transition from weaning to adulthood in the rat. We measured mitochondrial respiration using FAD- and NAD-linked substrates in 25 and 60 day old rats. The results show that adult rats exhibited significantly higher respiratory rates with all the substrates used except pyruvate. Our results indicate that the transition from weaning to adulthood induces important changes in hepatic mitochondrial function.

Heterogeneity of intratumour proliferative activity in primary breast cancer: biological and clinical aspects.

The present retrospective study was undertaken to verify whether the extent of intratumour proliferative activity variation or the method of quantifying tumour proliferative activity is related to biological characteristics and clinical outcome in a series of operable node-negative breast cancer patients. For tumour proliferative activity evaluation, the 3H-thymidine autoradiographic assay was used. After incubation of 3-8 samples from different areas of the equatorial section of each tumour for 1 h at 37 degrees C with 3H-thymidine, the following methods were used for evaluation of tumour cell labelling: mean tumour labelling index (LI), the highest labelling value from a specific area (LI-max), and the extent of intratumour labelling variation from several samples (LI-CV). LI-max was related to ER and PgR status, and linearly correlated with LI (c.c. = 0.92, P < 10(-6)) whereas LI-CV was independent of tumour size, grade ER and PgR status, but dependent on the number of tumour samples analysed for each tumour. After 5 years of median follow-up, disease-free survival was only related to tumour size (T1 versus T2: 84 versus 64%, P < 0.04 by log rank analysis) and different LI values (low versus high 3H-Tdr-LI:86 versus 61%, P < 0.03 by log rank analysis). LI-max and LI-CV values were not significantly related to clinical outcome. Cox multivariate analysis confirmed the independent prognostic value of LI and tumour size on disease-free survival.

Radiation therapy alone in stage III-B cancer of the uterine cervix--a 17-year old experience in southern Brazil.

PURPOSE: External irradiation followed by intracavitary therapy (EBIC) has been considered the standard treatment for stage III-B cancer of the uterine cervix. For different reasons, some patients are not suited for intracavitary therapy (ICT), and the treatment may be given entirely by external beam irradiation alone (EBRTA). The purpose of our study is to discuss treatment results and complications for patients undergoing EBIC or EBRTA. METHODS AND MATERIALS: A retrospective study was carried out on 202 eligible patients with stage III-B cancer of the uterine cervix admitted for radiotherapy from 1980-1997. Ninety-three patients were able to receive EBIC (50 Gy, 8 MV RX whole pelvis followed by one session of 38-45 Gy ICT to point A). The remaining received EBRTA (50-70 Gy for 5-9 or more weeks). Median follow-up procedure was 18.5 months (range: 4-182) for all patients and 26 months (range 4-147) for the patients at risk. RESULTS: The most frequent reason for precluding ICT was large residual tumor volume (32.1%). Ten-year overall survival rates, relapse free survival, and pelvic failure rate for the EBIC and EBRTA patients were, respectively, 22.5% x 15.6% (p = 0.0087), 23.5% x 14.8% (p = 0.005), and 51.6% x 68.8% (p = 0.005). However, when the same comparisons were performed with EBIC patients x EBRTA patients receiving a high dose schedule (60 Gy/6-8 wk to 70 Gy/7-9 wk), the results of the EBIC group remained higher, but the differences became insignificant: respectively, 22.5% x 18.9% (p = 0.17), 23.5% x 15.3% (p = 0.052), and 51.6% x 60.0% (p = 0.10). The distribution of complications was similar in both groups. CONCLUSIONS: We found that EBIC was the best treatment modality in our patients with stage III-B cancer of the uterine cervix, whereas for patients who were not candidates for ICT, EBRTA with a high dose schedule appears to be an efficient and safe alternative.

Syncopal sustained ventricular tachycardia in a patient with right ventricular dysplasia.

A 41-year-old man was hospitalized for syncopal sustained ventricular tachycardia with left bundle branch morphology. Diagnostic screening confirmed a right ventricular dysplasia: fibrofatty replacement of myocardium on endomyocardial biopsy and severe dilation of right ventricle with no left ventricular impairment was documented. His bundle recording showed an abnormally long HV interval, and programmed ventricular stimulation induced high-rate sustained ventricular tachycardia with left bundle branch block morphology associated with reduced systolic blood pressure and dizziness. Right ventricular burst pacing proved to be effective in restoring sinus rhythm. A single lead pectoral cardioverter-defibrillator was implanted and programmed for VVI and antitachycardia pacing, as first ventricular tachycardia therapeutic intervention. During 6-month follow-up, 1 asymptomatic ventricular tachycardia recurrence terminated by antitachycardia pacing was reported by the device. The possible role of the other therapeutic options such as drugs, ablation, and surgery for this specific case is also discussed.

Relationship between the resting metabolic rate and hepatic metabolism in rats: effect of hyperthyroidism and fasting for 24 hours.

We have examined the relationship between the changes in resting metabolic rate (RMR) and those in hepatic metabolism induced by hyperthyroidism and fasting for 24 h. We found that hyperthyroidism induced a significant increase in RMR, while fasting for 24 h reduced RMR in euthyroid but not in hyperthyroid rats. We have also measured oxygen consumption in isolated hepatocytes from euthyroid and hyperthyroid rats, fed or fasted for 24 h. Hyperthyroidism induced an increase in oxygen consumption in rat liver cells; fasting for 24 h increased respiratory rates in isolated liver cells from euthyroid but not from hyperthyroid rats. The findings showed that hyperthyroidism and fasting for 24 h have opposite effects on RMR but similar effects on hepatic metabolism. The results also indicated that the increase in RMR found in hyperthyroid rats is partly due to an increase in hepatic metabolism, while no correlation exists between variations in resting and hepatic metabolism induced by 24-h fasting.

Effect of thyroid state and cold exposure on rat liver mitochondrial protein mass and function.

The effects of thyroid state on liver mitochondrial protein mass was investigated in rats at 24 and 4 degrees C, as was oxidative phosphorylation using substrates which represent the final catabolic products of the metabolic fuels. In rats at 24 degrees C, a significant increase in mitochondrial protein mass (about +40%) was observed only in hyperthyroid animals, while a significant increase due to cold exposure was found in hypothyroid (+45%) and euthyroid (+35%) rats. In rats at 24 degrees C, hypothyroidism significantly decreased the oxidation of glutamate and palmitoyl carnitine but not of pyruvate, while hyperthyroidism only increased the oxidation of palmitoyl carnitine. On the other hand, exposure to cold significantly increased the oxidation of glutamate and pyruvate only in the presence of tri-iodothyronine. Our results underline not only the fact that a simple and single hypothesis for thyroid effects cannot be adopted, but also that any study concerning oxidative metabolism should be carried out using different substrates and involving different pathways of oxidation.

Thermic effect of food in hypothyroid rats.

The regulatory and obligatory components of cephalic and gastrointestinal phases of the thermic effect of food (TEF) were measured in control and hypothyroid rats. A significant decrease (P < 0.05) in regulatory and obligatory components of cephalic and gastrointestinal TEF, after either a control or energy-dense meal, was found in hypothyroid rats compared with control rats. Our findings indicate that hypothyroidism is associated with a decreased thermogenic response to food which contributes to the reduced energy expenditure of hypothyroid rats. Our results also suggest that tri-iodothyronine is involved in the regulation of postprandial thermogenesis directly as well as through its influence on beta-adrenergic response and insulin release.

Randomised clinical trial of adjuvant chemotherapy in patients with node-negative, fast-proliferating breast cancer.

A prospective randomised clinical trial in patients with node-negative, fast-proliferating breast cancer was initiated in January 1990 to verify the feasibility and reliability of a 3H-thymidine (3H-Tdr) autoradiographic assay in a prospective and consecutive series of node-negative patients and the therapeutic effect of adjuvant chemotherapy in patients with node-negative breast cancer and high tumour proliferative activity. Node-negative patients with a high 3H-Tdr Labelling Index (3H-Tdr-LI) were randomised to receive either no further treatment or combination chemotherapy consisting of fluorouracil, epirubicin plus cyclophosphamide (FEC) for 6 cycles. The autoradiographic assay was performed in 307 of 317 patients (97%) and was evaluable in 291 of 317 patients (92%). A total of 176 patients with a high 3H-Tdr-LI entered the clinical randomised study: 91 in the FEC arm and 85 in the control arm. Patient groups were fairly well balanced regarding the most important clinical and pathological characteristics. In total, 530 FEC cycles have been administered with an actual dose intensity of 90%. Patients receiving FEC demonstrated leucopenia in 35% of cases, alopecia in 70%, and loss of menses in premenopausal patients in an age-dependent manner. Patients are still being entered into the study.

The effect of thyroid state and cold exposure on rat liver oxidative phosphorylation.

In this paper we have examined the effect of cold exposure on hepatic mitochondrial state 3 respiration and ATP synthesis, using succinate as the substrate, in euthyroid, hypothyroid and hyperthyroid rats. The results show that cold exposure does not elicit any variation in the above parameters in euthyroid and hyperthyroid rats, whereas when hypothyroid rats are exposed to cold, a significant increase (about +45%) occurs in state 3 respiration and ATP synthesis. We have also measured succinic dehydrogenase specific activity and uncoupled respiration during cold exposure in various thyroid states. The finding that cold exposure elicits no variation in the above parameters indicates that there is some control on ATP synthase and/or adenine nucleotide translocator. The above findings, as a whole, suggest that cold exposure acts on oxidative phosphorylation only if triiodothyronine is lacking, by controlling ATP synthase and/or adenine nucleotide translocator.

Mitochondrial DNA, RNA and protein synthesis in normal, hypothyroid and mildly hyperthyroid rat liver during cold exposure.

We have examined in isolated liver mitochondria the effect of cold exposure on DNA, RNA and protein synthesis in normal, hypothyroid and mildly hyperthyroid rats. In normal rats DNA polymerase activity increased from the first day of cold exposure remaining high up to the fifteenth day. RNA polymerase and protein synthesis were stimulated from the fifth day of cold exposure, maintaining a high level up to the fifteenth day. These activities were related to serum triiodothyronine (T3) levels. Indeed propylthiouracil (PTU) administration to cold-exposed rats drastically depressed the above activities, whereas T3 administration to PTU-treated cold-exposed rats restored them to about the values prevalent in normal cold-exposed rats. The translation products analyzed by gel electrophoresis showed that different effects may be exerted by T3 depending on whether its circulating levels are physiologically or pharmacologically modified. These findings suggest that T3 may be involved in the regulation of the acclimation process by acting, presumably with a permissive role, on those activities which determine a modification of the mitochondrial morphometric features and an increase in mitochondria number and turnover.

The effect of thyroid state on respiratory activities of three rat liver mitochondrial fractions.

In this paper we report that three different rat liver mitochondrial fractions, differing in density, exhibit differential effects when the animals are made hypo- or hyperthyroid. The investigations have been performed by correlating the protein content, the succinic dehydrogenase behaviour and the respiratory features of the three fractions in different thyroid states with morphometric-stereologic analysis the electron micrographic level. The results indicate that the thyroid hormone influences both the mass and the functionality of the heavy (H) and light (L) fraction. In hypothyroid rats the H fraction increases (+43%) while the L fraction decreases (-32%) and their respiratory activity is drastically reduced. Adenosine triphosphate (ATP) synthesis in the H fraction is also inhibited. Triiodothyronine (T3) administration to the above animals restores the values observed in control rats. At morphometric level we note in hypothyroid rats an increase in the number of mitochondria together with a concomitant increase in the average volume of a single mitochondrion. We are inclined to explain the above results through an action exerted by T3 on a hypothetical mitochondrial cycle starting with the formation of light organelles from heavy ones.

In vitro antitumour activity and cellular pharmacological properties of the platinum-iminoether complex trans-[PtCl2[E-HN=C(OMe)Me]2].

The platinum complex trans-[PtCl2¿E-HN=C(OMe)Me¿2] was compared to cisplatin for cytotoxicity towards tumour cells, and for cellular pharmacological properties in A2780 and cisplatin-resistant A2780/Cp8 ovarian cancer cells. Trans-[PtCl2¿E-HN=C(OMe)Me¿2] was comparably cytotoxic to cisplatin (mean IC50 after 72 h exposure = 6. 1 microM and 7 microM, respectively) and did not show cross-resistance in A2780/Cp8 cells (resistance factor = 0.9). Cellular accumulation measurements after treatment with equimolar drug concentrations showed that trans-[PtCl2¿E-HN=C(OMe)Me¿2] entered both A2780 and A2780/Cp8 cells much more efficiently than cisplatin, whose accumulation was reduced in A2780/Cp8 cells. Unlike cisplatin, trans-[PtCl2¿E-HN=C(OMe)Me¿2] induced rapidly cell death and cell cycle modifications of treated cells, thus indicating substantially different mechanistic properties.