Survival after antireflux surgery versus medication in patients with reflux oesophagitis or Barrett's oesophagus: multinational cohort study.

BACKGROUND: The aim was to examine the hypothesis that antireflux surgery with fundoplication improves long-term survival compared with antireflux medication in patients with reflux oesophagitis or Barrett's oesophagus. METHOD: Individuals aged between 18 and 70 years with reflux oesophagitis or Barrett's oesophagus (intestinal metaplasia) documented from in-hospital and specialized outpatient care were selected from national patient registries in Denmark, Finland, Iceland, and Sweden from 1980 to 2014. The study investigated all-cause mortality and disease-specific mortality, comparing patients who had undergone open or laparoscopic antireflux surgery with fundoplication versus those using antireflux medication. Multivariable Cox regression analysis was used to estimate hazard ratios (HRs) with 95 per cent confidence intervals for all-cause mortality and disease-specific mortality, adjusted for sex, age, calendar period, country, and co-morbidity. RESULTS: Some 240 226 patients with reflux oesophagitis or Barrett's oesophagus were included, of whom 33 904 (14.1 per cent) underwent antireflux surgery. The risk of all-cause mortality was lower after antireflux surgery than with use of medication (HR 0.61, 95 per cent c.i. 0.58 to 0.63), and lower after laparoscopic (HR 0.56, 0.52 to 0.60) than open (HR 0.80, 0.70 to 0.91) surgery. After antireflux surgery, mortality was decreased from cardiovascular disease (HR 0.58, 0.55 to 0.61), respiratory disease (HR 0.62, 0.57 to 0.66), laryngeal or pharyngeal cancer (HR 0.35, 0.19 to 0.65), and lung cancer (HR 0.67, 0.58 to 0.80), but not from oesophageal cancer (HR 1.05, 0.87 to 1.28), compared with medication, The decreased mortality rates generally remained over time. CONCLUSION: In patients with reflux oesophagitis or Barrett's oesophagus, antireflux surgery is associated with lower mortality from all causes, cardiovascular disease, respiratory disease, laryngeal or pharyngeal cancer, and lung cancer, but not from oesophageal cancer, compared with antireflux medication.

Reintervention or mortality within 90 days of bariatric surgery: population-based cohort study.

BACKGROUND: Bariatric surgery carries a risk of severe postoperative complications, sometimes leading to reinterventions or even death. The incidence and risk factors for reintervention and death within 90 days after bariatric surgery are unclear, and were examined in this study. METHODS: This population-based cohort study included all patients who underwent bariatric surgery in one of the five Nordic countries between 1980 and 2012. Data on surgical and endoscopic procedures, diagnoses and mortality were retrieved from national high-quality and complete registries. Multivariable Cox regression analysis was used to calculate hazard ratios (HRs), adjusted for country, age, sex, co-morbidity, type of surgery and approach, year and hospital volume of bariatric surgery. RESULTS: Of 49 977 patients, 1111 (2·2 per cent) had a reintervention and 95 (0·2 per cent) died within 90 days of bariatric surgery. Risk factors for the composite outcome reintervention/mortality were older age (HR 1·65, 95 per cent c.i. 1·36 to 2·01, for age at least 50 years versus less than 30 years) and co-morbidity (HR 2·66, 1·53 to 4·62, for Charlson co-morbidity index score 2 or more versus 0). The risk of reintervention/mortality was decreased for vertical banded gastroplasty compared with gastric bypass (HR 0·37, 0·28 to 0·48) and more recent surgery (HR 0·51, 0·39 to 0·67, for procedures undertaken in 2010 or later versus before 2000). Sex, surgical approach (laparoscopic versus open) and hospital volume did not influence risk of reintervention/mortality, but laparoscopic surgery was associated with a lower risk of 90-day mortality (HR 0·29, 0·16 to 0·53). CONCLUSION: Reintervention and death were uncommon events within 90 days of bariatric surgery even in this unselected nationwide cohort from five countries. Older patients with co-morbidities have an increased relative risk of these outcomes.

ANTECEDENTES: La cirugía bariátrica conlleva un riesgo de complicaciones postoperatorias graves, que algunas veces ocasionan reintervenciones o incluso son causa de mortalidad. La incidencia y los factores de riesgo de reinterveniones y mortalidad a los 90 días tras cirugía bariátrica no están claros, y fueron examinados en este estudio. MÉTODOS: Todos los pacientes que fueron sometidos a cirugía bariátrica en uno de los cinco países nórdicos en 1980-2012 fueron incluidos en un estudio de cohortes de base poblacional. Los datos de los procedimientos quirúrgicos y endoscópicos, diagnóstico, y mortalidad se obtuvieron a partir de registros nacionales completos y de alta calidad. Mediante una regresión de Cox multivariable se obtuvieron los cocientes de riesgos instantáneos (hazard ratios, HR) y los intervalos de confianza 95% (i.c. del 95%) ajustados por país, edad, sexo, comorbilidad, y tipo, abordaje, año y volumen de casos de cirugía bariátrica del hospital. RESULTADOS: De un total de 49.977 pacientes, 1.111 (2,2%) precisaron una reintervención y 95 (0,2%) fallecieron durante los primeros 90 días tras la cirugía bariátrica. Los factores de riesgo para el resultado compuesto reintervención/mortalidad fueron la edad avanzada (HR = 1,7 (i.c. del 95% 1,4-2,0) edad ≥ 50 versus < 30 años)) y la comorbilidad (HR = 2,7 (i.c. del 95% 1,5-4,6) puntuación del índice de comorbilidad de Charlson ≥ 2 versus 0)). Se observó una disminución de los HRs tras la gastroplastia vertical con banda en comparación con el bypass gástrico (HR = 0,4, (i.c. del 95% 0,3-0,5)) y el periodo de estudio más reciente (HR = 0,5 (i.c. del 95% 0,4-0,7) ≥ 2010 versus < 2000)). El sexo, el abordaje quirúrgico laparoscópico versus abierto y el volumen del hospital no influyeron sobre el riesgo de reintervención/mortalidad, pero la cirugía laparoscópica se asoció con una mortalidad a los 90 días más baja (HR 0,3, i.c. del 95% 0,2-0,5). CONCLUSIÓN: La reintervención y la mortalidad son eventos infrecuentes durante los primeros 90 días tras la cirugía bariátrica, incluso en esta cohorte nacional y no seleccionada de cinco paises. Los pacientes mayores con comorbilidades tienen un riesgo relativo aumentado de reintervención y mortalidad.

Population-based cohort study of diabetes mellitus and mortality in gastric adenocarcinoma.

BACKGROUND: Gastric adenocarcinoma is a common cause of cancer death globally. It remains unclear whether coexisting diabetes mellitus influences survival in patients with this tumour. A cohort study was conducted to determine whether coexisting diabetes increases mortality in gastric adenocarcinoma. METHODS: This nationwide population-based cohort study included all patients diagnosed with gastric adenocarcinoma in Sweden between 1990 and 2014. Cox proportional hazards regression and competing risks regression were used to assess the influence of coexisting diabetes on disease-specific mortality in gastric adenocarcinoma with adjustment for sex, age, calendar year and co-morbidity (Charlson Co-morbidity Index score excluding diabetes). RESULTS: Among 23 591 patients with gastric adenocarcinoma, 2806 (11·9 per cent) had coexisting diabetes. Overall, patients with diabetes had a moderately increased risk of disease-specific mortality after diagnosis of gastric adenocarcinoma compared with those without diabetes, as shown by both Cox regression (hazard ratio (HR) 1·17, 95 per cent c.i. 1·11 to 1·22) and competing risks regression (sub-HR 1·08, 1·02 to 1·13). The HRs for disease-specific mortality were notably increased in diabetic patients without other co-morbidity (HR 1·23, 1·15 to 1·32) and in diabetic patients who had surgery with curative intent (HR 1·27, 1·16 to 1·38). CONCLUSION: These findings indicate a worse prognosis in patients with gastric adenocarcinoma and coexisting diabetes compared with those without diabetes.

Rapidly developing multimorbidity and disability in older adults: does social background matter?

BACKGROUND: Multimorbidity is among the most disabling geriatric conditions. In this study, we explored whether a rapid development of multimorbidity potentiates its impact on the functional independence of older adults, and whether different sociodemographic factors play a role beyond the rate of chronic disease accumulation. METHODS: A random sample of persons aged ≥60 years (n = 2387) from the Swedish National study on Aging and Care in Kungsholmen (SNAC-K) was followed over 6 years. The speed of multimorbidity development was estimated as the rate of chronic disease accumulation (linear mixed models) and further dichotomized into the upper versus the three lower rate quartiles. Binomial negative mixed models were used to analyse the association between speed of multimorbidity development and disability (impaired basic and instrumental activities of daily living), expressed as the incidence rate ratio (IRR). The effect of sociodemographic factors, including sex, education, occupation and social network, was investigated. RESULTS: The risk of new activity impairment was higher among participants who developed multimorbidity faster (IRR 2.4, 95% CI 1.9-3.1) compared with those who accumulated diseases more slowly overtime, even after considering the baseline number of chronic conditions. Only female sex (IRR for women vs. men 1.6, 95% CI 1.2-2.0) and social network (IRR for poor vs. rich social network 1.7, 95% CI 1.3-2.2) showed an effect on disability beyond the rate of chronic disease accumulation. CONCLUSIONS: Rapidly developing multimorbidity is a negative prognostic factor for disability. However, sociodemographic factors such as sex and social network may determine older adults' reserves of functional ability, helping them to live independently despite the rapid accumulation of chronic conditions.

Mangiferin blocks proliferation and induces apoptosis of breast cancer cells via suppression of the mevalonate pathway and by proteasome inhibition.

Mangiferin is a natural xanthone glycoside with therapeutic potential. Herein, its cytotoxic properties were explored in a human cell model of breast adenocarcinoma. The results supported the multi-target nature of mangiferin action, as the inhibition of three enzymatic systems, namely HMG-CoA reductase, the proteasome and plasmin, respectively in charge of regulating cholesterol homeostasis, protein turnover and cell adhesion, was documented for the first time. Globally, mangiferin was able to selectively block breast cancer cell growth by inducing apoptosis and by arresting cell proliferation through a combined action on cholesterol and proteasome pathways, as well as to inhibit plasmin-mediated mechanisms of cell migration.

Nutritional status and survival among old adults: an 11-year population-based longitudinal study.

BACKGROUND/OBJECTIVES: The impact of nutritional status on survival among community-dwelling older adults is unclear. We aimed to investigate the prevalence and association of poor nutritional status, including malnutrition and risk for malnutrition defined by the Mini-Nutritional Assessment-Short Form (MNA-SF) with survival, and to explore the role of relevant biomarkers (hemoglobin, albumin and C-reactive protein) in this association. SUBJECTS/METHODS: This study included 3041 participants aged ⩾ 60 in the Swedish National study on Aging and Care-Kungsholmen. On the basis of the total score in MNA-SF, nutritional status for each participant was assessed as normal (score 12-14), risk for malnutrition (8-11) or malnutrition (<8). Over an 11-year follow-up, survival status was observed. Data were analysed using logistic regression, flexible parametric survival and Laplace models. RESULTS: Of all the participants, 51 (1.7%) had malnutrition and 751 (24.7%) were at risk for malnutrition. The multi-adjusted hazard ratio (95% confidence interval) of mortality was 2.40 (1.56-3.67; P<0.001) for malnutrition and 1.49 (1.29-1.71; P<0.001) for risk for malnutrition. The median ages at death of participants with malnutrition and risk for malnutrition were ~3 and 1.5 years shorter than those with normal nutritional status, respectively, whereas malnutrition or risk for malnutrition together with abnormal biomarker (hemoglobin and albumin) levels was related to 1 year more shortened survival. CONCLUSIONS: Malnutrition and risk for malnutrition are highly prevalent and significantly associated with a shorter survival. Poor nutritional status in combination with abnormalities in the biomarkers is associated with even more shortened survival.

Enhanced seasonal exchange of CO2 by northern ecosystems since 1960.

Seasonal variations of atmospheric carbon dioxide (CO2) in the Northern Hemisphere have increased since the 1950s, but sparse observations have prevented a clear assessment of the patterns of long-term change and the underlying mechanisms. We compare recent aircraft-based observations of CO2 above the North Pacific and Arctic Oceans to earlier data from 1958 to 1961 and find that the seasonal amplitude at altitudes of 3 to 6 km increased by 50% for 45° to 90°N but by less than 25% for 10° to 45°N. An increase of 30 to 60% in the seasonal exchange of CO2 by northern extratropical land ecosystems, focused on boreal forests, is implicated, substantially more than simulated by current land ecosystem models. The observations appear to signal large ecological changes in northern forests and a major shift in the global carbon cycle.

Pazopanib and sunitinib trigger autophagic and non-autophagic death of bladder tumour cells.

BACKGROUND: Tyrosine kinase inhibitors (TKI) such as sunitinib and pazopanib display their efficacy in a variety of solid tumours. However, their use in therapy is limited by the lack of evidence about the ability to induce cell death in cancer cells. Our aim was to evaluate cytotoxic effects induced by sunitinib and pazopanib in 5637 and J82 bladder cancer cell lines. METHODS: Cell viability was tested by MTT assay. Autophagy was evaluated by western blot using anti-LC3 and anti-p62 antibodies, acridine orange staining and FACS analysis. Oxygen radical generation and necrosis were determined by FACS analysis using DCFDA and PI staining. Cathepsin B activation was evaluated by western blot and fluorogenic Z-Arg-Arg-AMC peptide. Finally, gene expression was performed using RT-PCR Profiler array. RESULTS: We found that sunitinib treatment for 24 h triggers incomplete autophagy, impairs cathepsin B activation and stimulates a lysosomal-dependent necrosis. By contrast, treatment for 48 h with pazopanib induces cathepsin B activation and autophagic cell death, markedly reversed by CA074-Me and 3-MA, cathepsin B and autophagic inhibitors, respectively. Finally, pazopanib upregulates the α-glucosidase and downregulates the TP73 mRNA expression. CONCLUSION: Our results showing distinct cell death mechanisms activated by different TKIs, provide the biological basis for novel molecularly targeted approaches.

Involvement of p53 in phthalate effects on mouse and rat osteoblasts.

The role of two estrogen-mimicking compounds in regulating osteoblast activities were examined. Previously, our attention was focused on benzyl butyl phthalate (BBP) and di-n-butyl phthalate (DBP) since previous works showed that they enter the cytoplasm, bioaccumulate, modify actin cytoarchitecture and exert mitogenic effects involving microfilament disruption, and nuclear actin and lamin A regulation in Py1a rat osteoblasts. In this study we showed that BBP and DBP cause DNA base lesions both in MT3T3-E1 osteoblasts and in mouse primary calvarial osteoblasts (COBs). In addition, treatment with the above effectors caused an increase of p53 and phospho-p53 (ser-15 and ser-20) as well as an increase of apoptotic proteins with consequent decrease of cell viability. Moreover, treatment with phthalates did not modified p53 and phospho-p53 expression in Py1a rat osteoblasts. It is of relevance that in p53 knockdown mouse osteoblasts a proliferative effect of phthalates, similar to that observed in rat Py1a osteoblasts, was found. In conclusion, our data demonstrated that phthalates induce osteoblast apoptosis, which is, at least in part, mediated by p53 activation, suggesting that the proliferative effects could be due to p53 missing activation or p53 mutation.

Glycosyl and polyalcoholic prodrugs of lonidamine.

Polyhydric alcohol derivatives of the anticancer agent lonidamine (LND) have been synthesized. The increased water solubility showed by prodrugs 4, 7, and 25 together with their logP values (2.19, 2.55, and 2.54, respectively) and chemical stability might be beneficial for prodrugs absorption after oral administration. Moreover, the new prodrugs undergo enzymatic hydrolysis in plasma and release LND demonstrating that they are promising candidates for in vivo investigations.

Capsaicin-induced apoptosis of glioma cells is mediated by TRPV1 vanilloid receptor and requires p38 MAPK activation.

We provide evidence on the expression of the transient receptor potential vanilloid type-1 (TRPV1) by glioma cells, and its involvement in capsaicin (CPS)-induced apoptosis. TRPV1 mRNA was identified by quantitative RT-PCR in U373, U87, FC1 and FLS glioma cells, with U373 cells showing higher, and U87, FC1 and FLS cells lower TRPV1 expression as compared with normal human astrocytes. By flow cytometry we found that a substantial portion of both normal human astrocytes, and U87 and U373 glioma cells express TRPV1 protein. Moreover, we analyzed the expression of TRPV1 at mRNA and protein levels of glioma tissues with different grades. We found that TRPV1 gene and protein expression inversely correlated with glioma grading, with marked loss of TRPV1 expression in the majority of grade IV glioblastoma multiforme. We also described that CPS trigger apoptosis of U373, but not U87 cells. CPS-induced apoptosis involved Ca(2+) influx, p38 but not extracellular signal-regulated mitogen-activated protein kinase activation, phosphatidylserine exposure, mitochondrial permeability transmembrane pore opening and mitochondrial transmembrane potential dissipation, caspase 3 activation and oligonucleosomal DNA fragmentation. TRPV1 was functionally implicated in these events as they were markedly inhibited by the TRPV1 antagonist, capsazepine. Finally, p38 but not extracellular signal-regulated protein kinase activation was required for TRPV1-mediated CPS-induced apoptosis of glioma cells.

Distinct thymocyte subsets express the vanilloid receptor VR1 that mediates capsaicin-induced apoptotic cell death.

Herein, we provide the first evidence on the capsaicin (CPS) receptor vanilloid receptor type-1 (VR1) by rat thymocytes, and its involvement in CPS-induced apoptosis. VR1 mRNA was identified by quantitative RT-PCR in CD5(+) thymocytes. By immunofluorescence and flow cytometry, we found that a substantial portion of CD5+ thymocytes, namely CD4+ and double negative (DN) cell subsets, express VR1 that was present on plasma membrane on discrete spots. By Western blot, VR1 protein was identified as a single band of 95 kDa. We also described that CPS could trigger two distinct pathways of thymocyte death, namely apoptosis and necrosis depending on the dose of CPS exposure. CPS-induced apoptosis involved intracellular free calcium (Ca2+) influx, phosphatidylserine exposure, mitochondrial permeability transmembrane pore (PTP) opening and mitochondrial transmembrane potential (Delta Psi m) dissipation leading to cytochrome c release, activation of caspase-9 and -3 and oligonucleosomal DNA fragmentation. VR1 was functionally implicated in these events as they were completely abrogated by the VR1 antagonist, capsazepine (CPZ). Finally, we demonstrated that VR1 expression on distinct thymocytes was associated with the selective ability of CPS to trigger DNA fragmentation in VR1+ CD4+ and DN thymocytes. Overall, our results suggest that the expression of VR1 on thymocytes may function as a sensor of harmful stimuli present in the thymic environment.

Involvement of alpha(v)beta3 integrin-like receptor and glycosaminoglycans in Candida albicans germ tube adhesion to vitronectin and to a human endothelial cell line.

The present study was undertaken to investigate the expression of alpha(v)beta3 and alpha(v)beta5 integrin-like vitronectin receptors (VNRs) on Candida albicans germ tube and their involvement in its adhesion to vitronectin (VN) and human endothelial cells. By immunofluorescence and FACS analysis, several monoclonal antibodies directed against human alpha(v) or beta3 integrin subunit or alpha(v)beta3 and alpha(v)beta5 heterodimers, positively stained C. albicans germ tubes. C. albicans germ tubes specifically adhered (45-50%) to VN and this adhesion was markedly inhibited by RGD-, but not RGE-containing peptides. Adhesion of C. albicans germ tubes to VN was strongly inhibited by anti-alphav, anti-beta3 or anti-alpha(v)beta3, but not by alpha(v)beta5 monoclonal antibody. C. albicans germ tube adhesion to VN was also inhibited by glycosaminoglycans (GAGs) such as heparin or chondroitin sulphate. Finally, we show that C. albicans germ tubes adhere to the human EA.hy 926 endothelial cell line. This adhesion is markedly blocked by anti-beta3 monoclonal antibody, GRGDSP peptide or heparin, and is completely abolished by their combination. Overall these results indicate that C. albicans germ tube adherence to VN and to a human endothelial cell line is mediated by alpha(v)beta3, but not by alpha(v)beta5-like integrin, and depends on GAGs which may act by regulating alpha(v)beta3 integrin-like/VN adhesive interaction.

Mitochondrial membrane potential in density-separated trout erythrocytes exposed to oxidative stress in vitro.

Previous literature reports have demonstrated that nucleated trout erythrocytes in condition of oxidative stress are subjected to DNA and membrane damage, and inactivation of glutathione peroxidase. The present study was undertaken to investigate if mitochondrial membrane potential in stressed conditions was also influenced. Density-separated trout erythrocyte fractions, obtained using a discontinuous Percoll gradient, were submitted to stress conditions and the mitochondrial membrane potential was determined by means of cytofluorimetric analysis after incubation of each subfraction with JC-1, a mitochondrial specific fluorescent probe. The results clearly show that the mitochondrial membrane potential decreased significantly in all erythrocyte fractions, also if the oxidative effect on mitochondria is more severe with increased density (age) of the cell. Ebselen was very effective in preventing mitochondrial depolarization in young as well as in old erythrocytes.

Local anticandidal immune responses in a rat model of vaginal infection by and protection against Candida albicans.

Humoral (antibody [Ab]) and cellular Candida-specific immune responses in the vaginas of pseudoestrus rats were investigated during three successive infections by Candida albicans. After the first, protective infection, Abs against mannan and aspartyl proteinase antigens were present in the vaginal fluid, and their titers clearly increased during the two subsequent, rapidly healing infections. In all animals, about 65 and 10% of vaginal lymphocytes (VL) were CD3(+) (T cells) and CD3(-) CD5(+) (B cells), respectively. Two-thirds of the CD3(+) T cells expressed the alpha/beta and one-third expressed the gamma/delta T-cell receptor (TCR). This proportion slightly fluctuated during the three rounds of C. albicans infection, but no significant differences between infected and noninfected rats were found. More relevant were the changes in the CD4(+)/CD8(+) T-cell ratio, particularly for cells bearing the CD25 (interleukin-2 receptor alpha) marker. In fact, a progressively increased number of both CD4(+) alpha/beta TCR and CD4(+) CD25(+) VL was observed after the second and third Candida challenges, reversing the high initial CD8(+) cell number of controls (estrogenized but uninfected rats). The CD3(-) CD5(+) cells also almost doubled from the first to the third infection. Analysis of the cytokines secreted in the vaginal fluid of Candida-infected rats showed high levels of interleukin 12 (IL-12) during the first infection, followed by progressively increasing amounts of IL-2 and gamma interferon during the subsequent infections. No IL-4 or IL-5 was ever detected. During the third infection, VL with in vitro proliferative activity in response to an immunodominant mannoprotein antigen of C. albicans were present in the vaginal tissue. No response to this antigen by mitogen-responsive blood, lymph node, and spleen cells was found. In summary, the presence of protective Ab and T helper type 1 cytokines in the vaginal fluids, the in vitro proliferation of vaginal lymphocytes in response to Candida antigenic stimulation, and the increased number of activated CD4(+) cells and some special B lymphocytes after C. albicans challenge constitute good evidence for induction of locally expressed Candida-specific Ab and cellular responses which are potentially involved in anticandidal protection at the vaginal level.

DNA vaccination with full-length or truncated neu induces protective immunity against the development of spontaneous mammary tumors in HER-2/neu transgenic mice.

Genetic immunization against tumor antigens is an effective way to induce an immune response able to oppose cancer progression. Overexpression of HER-2/neu can lead to neoplastic transformation and has been found in many human primary breast cancers. We constructed DNA expression vectors encoding the full-length neu oncogene of rat cDNA (pCMV-NeuNT), the neu extracellular domain (pCMV-ECD), or the neu extracellular and transmembrane domains (pCMV-ECD-TM). We evaluated whether i.m. injection of these plasmids induces protection against the development of mammary tumors occurring spontaneously in FVB/N neu-transgenic mice. We found that pCMV-ECD-TM induced the best protection, whereas both pCMV-ECD and pCMV-NeuNT were less effective. The coinjection with a bicistronic vector for murine IL-12 increased the efficacy of pCMV-ECD and pCMV-NeuNT plasmids, and led to the same protection obtained with pCMV-ECD-TM alone. Anti-neuECD antibodies were detected in pCMV-ECD-TM vaccinated mice and, after coinjection with pCMV-IL12 plasmids, they appeared also in animals immunized with pCMV-ECD. Our data demonstrate the effectiveness of DNA vaccination using truncated Neu plasmids in inducing antitumor protection in a spontaneous mammary tumor model.

Morphological and functional changes of mitochondria from density separated trout erythrocytes.

Density separated trout erythrocytes, using a discontinuous Percoll gradient, yielded three distinct subfractions (top, middle and bottom) since older cells are characterized by increasing density. Cells from each subfraction were incubated with mitochondria-specific fluorescent probe Mitotracker and JC-1 in order to assess mitochondrial mass and membrane potential by means of cytofluorimetric analysis, confocal microscopy and subsequent computer-aided image analysis allowing a detailed investigation at single cell level. Both cytofluorimetric data and image analysis revealed changes in size and redistribution of mitochondria starting from the light fraction to the bottom. In particular in young erythrocytes small mitochondria were detected localized exclusively around the nucleus in a crown-like shape, the middle fraction revealed enlarged mitochondria partially scattered throughout the cytosol, whereas the last fraction represented again mitochondria with reduced size being distinctly dispersed throughout the cytosol in the cells. Concerning membrane potential considerations, our study revealed a dramatic decrease of DeltaPsi(m) in the bottom layer cell mitochondria compared to the top and unusual membrane potential increase of a subpopulation of enlarged mitochondria. DeltapH was also investigated in the three fractions by pretreating the cells with nigericin, allowing to confirm a mitochondrial energetic impairment in older cells.

Impairment of rat thymocyte differentiation and functions by neonatal capsaicin treatment is associated with induction of apoptosis.

The direct and indirect interaction between the nervous system and its transmitters with the immune system was evaluated in the rat by using the neurotoxin capsaicin (Caps). In the present study we investigated the effect of Caps administration to neonatal rats on thymocyte subpopulation distribution and functions at different times after treatment. Caps treatment results in a marked reduction of thymus weight and cellularity. As shown by immunofluorescence and FACS analysis, profound depletion of double negative (DN), double positive (DP), and single positive (SP) CD4(+) cells was already evident at day 7 after treatment and persisted until day 28. Reduced numbers of SP CD8(+) cells were observed only at later time points. Analysis of TCR phenotype indicates that CD5(+) TCR gamma/delta(+) are particularly sensitive to neonatal Caps treatment. Caps-induced thymocyte depletion was associated with reduced proliferation in response to T cell mitogens. Moreover, in situ TUNEL reaction and agarose gel electrophoresis indicate that neonatal Caps treatment induces apoptosis of thymus cells. Morphological analysis reveals the presence of apoptotic cells in the subcapsular thymus cortical region. Overall our results suggest that Caps when administered at birth, profoundly affects T cell differentiation, likely through its ability to activate apoptotic cell death program.

The efficacy of acquired humoral and cellular immunity in the prevention and therapy of experimental fungal infections.

In the past two decades, numerous studies have documented the importance of acquired immunity for host defense against invasive fungal infections. There is widespread consensus in the field of medical mycology that cellular immunity is critical for successful host defense against fungi. However, in recent years several studies have established the potential efficacy of humoral immunity in host protection against two major fungal pathogens: Candida albicans and Cryptococcus neoformans. For C. albicans, antibodies to mannan, proteases and a heat shock proteins have been associated with protection against infection. Furthermore, anti-idiotypic antibodies to antibodies recognizing killer toxin from Pichia anomala and mimicking natural anti-killer toxin receptor antibodies can protect against C. albicans and other microorganisms. For C. neoformans, antibodies to the capsular glucuronoxylomannan have been shown to mediate protection in animal models of infection. Vaccines that induce protective antibodies have been shown to protect against experimental C. albicans and C. neoformans infection. In contrast, humoral immunity has not yet been demonstrated to mediate protection against Coccidioides immitis. For C. immitis, protection against infection is thought to rely on T cell mediated immunity, and the emphasis is on identifying the antigens that stimulate protective cellular immune responses and several candidate vaccines have been identified. These results provide encouragement for the view that acquired immune responses can be mobilized for the prevention and treatment of fungal infections.