MKRN3 circulating levels in girls with central precocious puberty caused by MKRN3 gene mutations

PURPOSE

MKNR3 is a paternally expressed gene whose mutations are the main cause of central precocious puberty (CPP). Protein circulating levels can be easily measured, as demonstrated in idiopathic CPP and healthy controls. No data are available for patients harboring an MKRN3 mutation. Our aim was to perform MKRN3 mutation screening and to investigate if circulating protein levels could be a screening tool to identify MKRN3 mutation in CPP patients.

METHODS

We enrolled 140 CPP girls and performed MKRN3 mutation analysis. Patients were stratified into two groups: idiopathic CPP (iCPP) and MKRN3 mutation-related CPP (MKRN3-CPP). Clinical characteristics were collected. Serum MKRN3 values were measured by a commercially available ELISA assay kit in MKRN3-CPP and a subgroup of 15 iCPP patients.

RESULTS

We identified 5 patients with MKRN3 mutations: one was a novel mutation (p.Gln352Arg) while the others were previously reported (p.Arg328Cys, p.Arg345Cys, p.Pro160Cysfs*14, p.Cys410Ter). There was a significant difference in circulating MKRN3 values in MKRN3-CPP compared to iCPP (p < 0.001). In MKRN3-CPP, the subject harboring Pro160Cysfs*14 presented undetectable levels. Subjects carrying the missense mutations p.Arg328Cys and p.Gln352Arg showed divergent circulating protein levels, respectively 40.56 pg/mL and undetectable. The patient with the non-sense mutation reported low but measurable MKRN3 levels (12.72 pg/mL).

CONCLUSIONS

MKRN3 defect in patients with CPP cannot be predicted by MKRN3 circulating levels, although those patients presented lower protein levels than iCPP. Due to the great inter-individual variability of the assay and the lack of reference values, no precise cut-off can be identified to suspect MKRN3 defect.

Different seminal ejaculated fractions in artificial insemination condition the protein cargo of oviductal and uterine extracellular vesicles in pig

The seminal plasma (SP) is the liquid component of semen that facilitates sperm transport through the female genital tract. SP modulates the activity of the ovary, oviductal environment and uterine function during the periovulatory and early pregnancy period. Extracellular vesicles (EVs) secreted in the oviduct (oEVs) and uterus (uEVs) have been shown to influence the expression of endometrial genes that regulate fertilization and early embryo development. In some species, semen is composed of well-separated fractions that vary in concentration of spermatozoa and SP composition and volume. This study aimed to investigate the impact of different accumulative fractions of the porcine ejaculate (F1, composed of the sperm-rich fraction, SRF; F2, composed of F1 plus the intermediate fraction; F3, composed of F2 plus the post-SRF) on oEVs and uEVs protein cargo. Six days after the onset of estrus, we determined the oEVs and uEVs size and protein concentration in pregnant sows by artificial insemination (AI-sows) and in non-inseminated sows as control (C-sows). We also identified the main proteins in oEVs and uEVs, in AI-F1, AI-F2, AI-F3, and C-sows. Our results indicated that although the size of EVs is similar between AI- and C-sows, the protein concentration of both oEVs and uEVs was significantly lower in AI-sows (p < 0.05). Proteomic analysis identified 38 unique proteins in oEVs from AI-sows, mainly involved in protein stabilization, glycolytic and carbohydrate processes. The uEVs from AI-sows showed the presence of 43 unique proteins, including already-known fertility-related proteins (EZR, HSPAA901, PDS). We also demonstrated that the protein composition of oEVs and uEVs differed depending on the seminal fraction(s) inseminated (F1, F2, or F3). In conclusion, we found specific protein cargo in oEVs and uEVs according to the type of semen fraction the sow was inseminated with and whose functions these specific EVs proteins are closely associated with reproductive processes.

Boar sperm motility is modulated by CCK at a low concentration of bicarbonate under capacitation conditions

In a previous study, our group detected the cholecystokinin (CCK) protein in the porcine oviduct. This fact, together with the involvement of CCK in the regulation of sperm protein tyrosine phosphorylation by the modulation of HCO₃ ^- uptake (in mouse and human) suggests a role of CCK during sperm capacitation. Therefore, on the one hand, the expression of CCK receptors (CCK1R and CCK2R) on boar testes has been investigated and probed also, on the other hand, boar spermatozoa (from seminal doses of 1-day and 5-day storage) were exposed to different concentrations of CCK (0-control, 25 or 50 μM) in a medium supporting capacitation supplemented with 0, 5 or 25 mmol/L of HCO₃ ^- for 1h at 38.5 °C. Sperm motion (total and progressive motility), kinetic parameters, viability, acrosome status and mitochondrial activity were determined. No differences between groups (0, 25 or 50 μM of CCK) were observed when HCO₃ ^- was absent in the media (p> 0.05). However, the results showed that when the media was supplemented with 5 mmol/L HCO₃ ^- in 1-day seminal doses storage, linearity index (LIN, %), straightness index (STR, %) and oscillation index (WOB, %) (sperm kinetics parameters) increased in the presence of CCK regardless the concentration (p< 0.05). Nevertheless, CCK in sperm from 5-day storage only increased the WOB parameter in comparison to the control (p< 0.05). Furthermore, the average amplitude of the lateral displacement of the sperm head (ALH, μm) and curvilinear velocity (VCL, μm/s) decreased when CCK was present, depending on its concentration and sperm aging (1-day vs. 5-days) (p< 0.05). In the case of the media supporting capacitation supplemented with 25 mmol/L HCO₃ ^- , any differences were observed except for sperm viability in the 5-day seminal doses which increases in the 50 μM-CCK group compared to the control (p< 0.05). In conclusion, these data suggest an implication of CCK protein during sperm capacitation under low bicarbonate concentration increasing the sperm linear trajectory.

Higher baseline TSH levels predict early hypothyroidism during cancer immunotherapy

BACKGROUND AND PURPOSE

Immune checkpoint inhibitors (ICIs) are monoclonal antibodies that enhance the immune response against cancer cells. ICIs are generally well tolerated, although endocrine immune-related adverse events (irAEs) are common. We investigated the risk factors for thyroid irAEs in patients treated with ICIs. Moreover, we evaluated the clinical outcome of subjects who became hypothyroid compared to euthyroid patients.

PATIENTS AND METHODS

We retrospectively analyzed a series of 195 consecutively subjects treated with ICIs for metastatic tumors at the University of Naples "Federico II" between January 2014 and March 2020. Only subjects tested for thyroid function before and during the treatment with ICIs were included.

RESULTS

In the 96 patients treated with ICIs who were included [66 males, median age: 62 years (27-87)], thyroid irAEs occurred in 36 (37.5%), 16 (16.7%) a transient thyrotoxicosis, and 20 (20.8%) an hypothyroidism (in nine subjects hypothyroidism was preceded by a transient thyrotoxicosis). Only baseline TSH levels above 1.67 mIU/L and positive anti-thyroid antibodies (Ab-T) were associated with a higher risk of hypothyroidism. Patients with hypothyroidism during ICI treatment showed an improved 2-year PFS (HR = 0.82 CI 0.47-1.43; p = 0.0132) and OS (HR = 0.38 CI 95% 0.17-0.80; p = 0.011) compared to euthyroid patients.

CONCLUSIONS

Baseline TSH levels above 1.67 mIU/L and presence of Ab-T are risk factors for the development of thyroid irAEs. Patients affected by thyroid irAEs showed a longer survival than patients who remained euthyroid.

Inter-fractional monitoring of [Formula: see text]C ions treatments: results from a clinical trial at the CNAO facility

The high dose conformity and healthy tissue sparing achievable in Particle Therapy when using C ions calls for safety factors in treatment planning, to prevent the tumor under-dosage related to the possible occurrence of inter-fractional morphological changes during a treatment. This limitation could be overcome by a range monitor, still missing in clinical routine, capable of providing on-line feedback. The Dose Profiler (DP) is a detector developed within the INnovative Solution for In-beam Dosimetry in hadronthErapy (INSIDE) collaboration for the monitoring of carbon ion treatments at the CNAO facility (Centro Nazionale di Adroterapia Oncologica) exploiting the detection of charged secondary fragments that escape from the patient. The DP capability to detect inter-fractional changes is demonstrated by comparing the obtained fragment emission maps in different fractions of the treatments enrolled in the first ever clinical trial of such a monitoring system, performed at CNAO. The case of a CNAO patient that underwent a significant morphological change is presented in detail, focusing on the implications that can be drawn for the achievable inter-fractional monitoring DP sensitivity in real clinical conditions. The results have been cross-checked against a simulation study.

Effect of temperature and cell concentration on dolphin (Tursiops truncatus) spermatozoa quality evaluated at different days of refrigeration

The use of cryopreserved dolphin spermatozoa facilitates the exchange of genetic material between aquatic parks and makes spermatozoa accessible to laboratories for studies to further our understanding of marine mammal reproduction. Sperm cryopreservation in the bottlenose dolphin (Tursiops truncatus) has been developed for the exchange of gametes within the ex situ population. The aim of this study was to develop an effective method for refrigeration of bottlenose dolphin spermatozoa diluted in a commercial extender (BTS). In Experiment 1, the effect of temperature (5 compared with 15 °C) on sperm quality was evaluated during 7 days of storage at 100 × 10⁶ spermatozoa/ml. In Experiment 2, the effect of the storage concentration (100 × 10⁶ compared with 20 × 10⁶ spermatozoa/ml) on sperm quality was assessed during 7 days of storage at 5 °C. In Experiment 1, total motility (including % of rapid sperm) was greater at 5 than 15 °C. When the effect of storage concentration was evaluated (Experiment 2), total motility and ALH were greater at the higher storage concentration (100 × 10⁶ spermatozoa/ml). For both experiments, values for viability, acrosome integrity, and normal morphology variables were consistent throughout the 7 days of refrigeration. In Experiment 3, a microbiological study was performed to evaluate the effect of the refrigeration temperature and days of storage on bacterial growth. The results of microbiological analysis indicated there was Staphylococcus aureus in some samples, however, there was no effect of temperature or days of refrigeration. In conclusion, bottlenose dolphin semen can be refrigerated for a short to medium period of storage and there is maintenance of functionality of sperm when stored at 100 × 10⁶ spermatozoa/ml at 5 °C.

Effect of boar seminal dose type (cervical compared with post-cervical insemination) on cooling curve, sperm quality and storage time

Seminal doses used for cervical and post-cervical artificial insemination (CAI and PCAI, respectively) vary in volume, the number of spermatozoa and packaging. The aim was to evaluate the outcomes when there was use of routine processing procedures for CAI- and PCAI-doses. Two different types of seminal doses were processed: 1) CAI: 2.7 × 10⁹ sperm/80 ml; 2) PCAI: 1.5 × 10⁹ sperm/45 ml. In Experiment 1, the cooling curve of seminal doses during processing occurred in two phases: 1st) At room temperature (23.4 ± 0.5 °C) from 0 (just after packaging) to 120 min; 2nd) At refrigeration (15.7 ± 0.8 °C) from 121-240 min. For the PCAI-doses, the time required to reach room temperature was 47 min compared to 107 min for CAI-doses (decreasing velocity of 0.093 °C/min and 0.048 °C/min, respectively). During refrigeration, for the PCAI-doses the time required to reach the desired preservation temperature was 20 min less than for CAI-doses (PCAI: 90 min, 0.074 °C/min; CAI: 110 min, 0.066 °C/min). In Experiment 2, sperm motility, kinetic parameters and acrosome damage for both types of doses were evaluated at 0, 24, 48 and 72 h of refrigeration. Also, morphology, pH, and osmolality were assessed at 0 and 72 h. Values for all these did not differ between CAI- and PCAI-doses. In conclusion, PCAI-doses took less time than CAI-doses to reach the desired temperature, but sperm quality was similar for CAI- and PCAI-doses during storage. Nevertheless, the different cooling curves should be taken into consideration for further investigation.

Local ablative therapy of oligoprogressive TKI-treated thyroid cancer

Metastatic cancer patients generally respond well to treatment with tyrosine kinase inhibitors (TKIs). However, TKI resistance occurs in almost all cases and often leads to a change in treatment. Recent guidelines, including thyroid cancer, raised the possibility of locally treating TKI-resistant oligoprogressive disease, i.e., one or a few progressing lesions in an otherwise treatment-responsive metastatic cancer, thereby obviating the need to change the ongoing TKI. To determine the benefits of this intervention, we reviewed studies on the use of LAT for TKI-treated oligoprogressive cancers. We found that in non-small cell lung cancer at least, LAT prolongs disease control and the duration of exposure to a TKI irrespective of the LAT used. Moreover, we reviewed the local ablative therapies (LATs) that are feasible for the local control of oligoprogressive thyroid cancer. Lastly, we report two illustrative cases of patients with oligoprogressive thyroid cancer treated with two different LATs while on therapy with TKIs. Both LATs extended the duration of disease control and the time of exposure to the ongoing TKI, thereby indicating that LAT is a favorable option for TKI-treated oligoprogressive thyroid cancer. Prospective randomized studies are needed to verify the benefit of LATs in terms of progression-free and overall survival in this increasingly frequent clinical setting.

Adult neural stem cell fate is determined by thyroid hormone activation of mitochondrial metabolism

Objective

In the adult brain, neural stem cells (NSCs) located in the subventricular zone (SVZ) produce both neuronal and glial cells. Thyroid hormones (THs) regulate adult NSC differentiation towards a neuronal phenotype, but also have major roles in mitochondrial metabolism. As NSC metabolism relies mainly on glycolysis, whereas mature cells preferentially use oxidative phosphorylation, we studied how THs and mitochondrial metabolism interact on NSC fate determination.

Methods

We used a mitochondrial membrane potential marker in vivo to analyze mitochondrial activity in the different cell types in the SVZ of euthyroid and hypothyroid mice. Using primary adult NSC cultures, we analyzed ROS production, SIRT1 expression, and phosphorylation of DRP1 (a mitochondrial fission mediator) as a function of TH availability.

Results

We observed significantly higher mitochondrial activity in cells adopting a neuronal phenotype in vivo in euthyroid mice. However, prolonged hypothyroidism reduced not only neuroblast numbers but also their mitochondrial activity. In vitro studies showed that TH availability favored a neuronal phenotype and that blocking mitochondrial respiration abrogated TH-induced neuronal fate determination. DRP1 phosphorylation was preferentially activated in cells within the neuronal lineage and was stimulated by TH availability.

Conclusions

These results indicate that THs favor NSC fate choice towards a neuronal phenotype in the adult mouse SVZ through effects on mitochondrial metabolism.

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Thyroid hormones (TH) favor neuronal fate decision in the adult sub-ventricular zone (SVZ).

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Mitochondrial activity and ROS production are higher in cells differentiating to neuronal fate.

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TH activate the fission-inducing factor DRP1 in cells acquiring a neuronal fate.

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TH favor a neuronal fate in the adult SVZ through induction of mitochondrial respiration.

High-normal fasting glucose levels are associated with increased prevalence of impaired glucose tolerance in obese children

The natural history of impaired glucose tolerance (IGT) and Type 2 diabetes among obese children is not clear. Although the cut-off for impaired fasting glucose (IFG) has recently been changed from 110 (6.1 mmol/l) to 100 mg/dl (5.6 mmol/l), it does not seem a reliable way to find all subjects with impaired glucose homeostasis. The aim of our study was to determine whether high-normal fasting glucose level could predict the occurrence of IGT and metabolic syndrome. Three hundred and twenty-three Italian obese children and adolescents were included in the study (176 females, mean age 11+/-2.9 yr; mean body mass index z-score: 3+/-0.6). Waist circumference, serum glucose, insulin, triglyceride, cholesterol HDL, blood pressure were evaluated and an oral glucose tolerance test (OGTT) was performed. The prevalence of IFG and IGT were respectively 1.5% (5 subjects) and 5% (18 patients); no diabetic patients were found. Metabolic syndrome was diagnosed in 20% of patients. Fasting glycemia values <100 mg/dl (5.6 mmol/l) have been divided in quintiles. Metabolic syndrome prevalence increased across quintiles, although not in a statistically significantly manner, but it could depend on the selected diagnostic criteria as no univocal definition exists for metabolic syndrome in youths. Interestingly high-normal fasting plasma glucose levels constitute an independent risk factor for IGT among obese children and adolescents; therefore, this very easy-to-use parameter may help to identify obese patients at increased risk of diabetes or at least could suggest in which subjects to perform an OGTT.

Mitochondrial genome involvement in ischemia/reperfusion-induced adaptive changes in human myocardial cells

AIM

Following previous studies on the ischemia-induced adaptive changes in human cardiac mitochondria, we examined in the present paper the interaction between nitric oxide-induced (NO) partial inhibition of Cyt. c oxidase (Cyt.OX) and mitochondrial encoded subunit 2 expression. Aim of the study was to investigate specific stages of the biochemical and molecular cascade which takes place in cytoprotective mechanisms of ischemic and reperfused cardiac cell.

METHODS

We examined human left ventricle samples obtained from 20 patients undergoing elective valve surgery before aortic cross-clamping, 20+/-2 min (prolonged ischemia), 58+/-5 min after cross-clamping (intermittent ischemia) and 21+/-4 min after reconstitution of coronary blood flow (reperfusion). Cyt.OX activity was determined by spectrophotometric method and adenosine triphosphate (ATP) content using bioluminescent assay. Malondialdehyde (MDA) assumed as reactive oxygen species (ROS) generation marker was determined by high-performance liquid chromatography method. On the same cardiac samples mitochondrial encoded Cyt.OX subunit 2 expression was examined by immunoblot analysis and blu native gel electrophoresis method. Statistical study of obtained data was performed using repeated measures analysis of variance (ANOVA).

RESULTS

Prolonged as well intermittent ischemia caused reduction of Cyt.OX activity and ATP, a moderate accumulation of ROS and down-regulation of Cyt.OX subunit 2. When reperfused the cardiomyocytes showed a progressive increase of Cyt.OX activity, ATP pools and Cyt.OX subunit 2 expression. ROS generation was significantly increased by the rapid oxygen re-immission in the cardiac cell.

CONCLUSIONS

These data confirm the suggestion that prolonged as well as intermittent ischemia induces activation of cytoprotective mechanisms crucial for cardiac cell survival. Indeed, co-ordinated down-regulation of Cyt.OX activities, ATP pools and mitochondrial encoded Cyt.OX subunit 2 are in favour of an ischemia-activated adaptive mechanism leading to transient and reversible oxidative injury. This observation is confirmed by reduction of apoptosis molecular markers and by complete recovery of mitochondrial oxidative activities in reperfused cardiac tissue.

Mechanisms of cell protection by adaptation to chronic and acute hypoxia: molecular biology and clinical practice

Several experimental and clinical studies have shown that specific biochemical and molecular pathways are involved in the myocardial and skeletal muscle cell tolerance to acute and/or chronic hypoxic injury. A number of different factors were proposed to play a role in the preservation of tissue viability, but to a few of them a pivotal role in the adaptive mechanisms to hypoxic stimuli could be ascribed. Starting from the observation that mitochondrial electron transport chain (ETC) enzymic complexes are the targets of oxygen reduced availability, most of data are compatible with a mechanism of enzymic adaptation in which the nitric oxide (NO) generation plays the major role. If the partial and reversible NO-induced inhibition of ETC enzymic complexes represents the most rapid and prominent adaptive mechanism in counteracting the damaging effects of hypoxia, the sarcolemmal and mitochondrial K+(ATP) channels activation results to be closely involved in cytoprotection. This process is depending on protein kinase C (PKC) isoform activation triggered by reactive oxygen species (ROS) generation, adenosine triphosphate (ATP) depletion and Ca++ overload. It is well known that all these factors are present in hypoxia-induced oxidative damage and mitochondrial Ca++ altered pools represent powerful stimuli in the damaging processes. The activation of mitochondrial K+(ATP) channels leads to a significant reduction of Ca++ influx and attenuation of mitochondrial Ca++ overload. Closely linked to these adaptive changes signal transduction pathways are involved in the nuclear DNA damage and repair mechanisms. On this context, an essential role is played by the hypoxia-induced factor-1alpha (HIF-1alpha) in terms of key transcription factor involved in oxygen-dependent gene regulation. The knowledge of the biochemical and molecular sequences involved in these adaptive processes call for a re-evaluation of the therapeutic approach to hypoxia-induced pathologies. On this light, some specific aspects of the therapeutic management of critically ill patients are taken into consideration and discussed in relation to the cellular biodynamics.

Ozonized autohaemotransfusion and fibrinolytic balance in peripheral arterial occlusive disease

The acute effects of a major ozonized autohaemotransfusion on blood fibrinolytic capacity were evaluated in 20 subjects affected by peripheral arterial occlusive disease (PAOD). The parameters examined were tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor type-1 (PAI-1). In subjects not previously submitted to autohaemotransfusion ('unaccustomed' subjects), whether they were PAOD patients or healthy volunteers, the PAI-1/t-PA ratio in the blood samples taken 15 min before the autohaemotransfusion was higher (P < or = 0.05) than at baseline. These changes were independent of the presence of ozone in the autohaemotransfusion blood. Values in both healthy and PAOD-affected individuals were again at baseline 120 min after the end of autohaemotransfusion. In PAOD patients and in healthy subjects previously submitted to several autohaemotransfusions ('accustomed' subjects), the PAI-1/t-PA ratio did not significantly change before, during and after an additional autohaemotransfusion. The results (the increased heart rate and epinephrine and norepinephrine urinary excretion only in non-accustomed subjects) suggest that the acute fibrinolytic imbalance is caused by the apprehensive state produced by the procedure in unaccustomed subjects. Autohaemotransfusion with ozonized blood per se does not significantly influence the fibrinolytic balance.

Ozonized autohemotransfusion improves hemorheological parameters and oxygen delivery to tissues in patients with peripheral occlusive arterial disease

Twenty-seven subjects suffering from peripheral occlusive arterial disease (POAD, clinical stage II-III according to Fontaine) were enrolled in this study to evaluate the effect of oxygen-ozone therapy upon hemorheological parameters and hemoglobin-oxygen affinity in patients with POAD. All patients underwent a major ozonized autohemotransfusion consisting of the slow reinfusion of 100 ml of autologous blood, previously exposed to a O(2)-O(3) mixture in a glass box for 10 min. Whole blood viscosity, erythrocyte filterability, hematocrit, and fibrinogen levels were assessed at the basal time and 30 min after the reinfusion of ozonized blood. At the same time p50 standard (p50std) values (an indicator of hemoglobin-oxygen affinity) and plasma values of malonyl dialdehyde (MDA, an indicator of lipid peroxidation) were evaluated. At the baseline, patients had significantly higher ( p<0.05- p<0.001) whole blood viscosity, MDA, and p50std values and significantly lower blood filterability ( p<0.01) as compared with 20 matched healthy volunteers (controls). Thirty minutes after the end of a major autohemotransfusion, whole blood viscosity significantly decreased ( p<0.01). This was accompanied by a significant fall in plasma fibrinogen level ( p<0.01) with no change in hematocrit. Blood filterability, MDA plasma level, and p50std values increased significantly at the same time ( p<0.01- p<0.005). The 2,3-DPG value did not change significantly. No significant changes occurred when the same patients received a non-ozonized autohemotransfusion (control test). In conclusion, ozonized autohemotransfusion may be useful to improve both the poor rheological properties of the blood and the oxygen delivery to tissues in patients suffering from POAD.

Lovastatin-induced apoptosis in thyroid cells: involvement of cytochrome c and lamin B

OBJECTIVE

The 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor, lovastatin, induces apoptosis in the thyroid cell line TAD-2 and in proliferating normal human thyroid cells in culture, through a p53-independent mechanism involving caspase-3-like proteases. The combination of lovastatin with other anti-neoplastic drugs potentiates chemotherapy of tumors. This drug has been suggested for the chemotherapy of tumors and is potentially useful in the treatment of thyroid proliferative diseases. Based on this premise, we analyzed in more detail the role of some molecular effectors and the role of the caspase family proteases in the lovastatin-induced apoptotic pathway in TAD-2 cells.

METHODS

TAD-2 cells were treated with lovastatin to induce apoptosis, and expression of p53, Bc1-2, Bcl-XL and Bax was analyzed by Western blot. Caspase activation was evaluated by the assay of enzymatic activity with chromogenic peptides and Western blot. Nuclear, cytosolic and mitochondrial fractions were prepared by differential centrifugation and the presence of cytochrome c and lamin B was evaluated by Western blot.

RESULTS

p53, Bc1-2, Bcl-XL and Bax protein expression were unchanged during apoptosis. Cytochrome c was released from mitochondria into the cytosol, a pivotal event in the activation of caspase-3. Caspase-3 and -6 but not caspase-2 were activated, and proteolysis of PARP and lamin B, a caspase-6 substrate located in the inner nuclear membrane, was demonstrated by Western blot. The nuclear localization of lamin B was also inhibited by lovastatin.

CONCLUSIONS

These data demonstrate that, in TAD-2 thyroid cells, lovastatin induces lamin B proteolysis and inhibits its nuclear localization and induces cytochrome c release from mitochondria into the cytosol.

Role of hyperbaric oxygen exposure in reduction of lipid peroxidation and in multiple organ failure induced by zymosan administration in the rat

The aim of the present study was to evaluate the effects of hyperbaric oxygen (HBO) therapy on multiple organ failure induced by zymosan. Administration of zymosan (500 mg/kg) in the rat induced neutrophil infiltration in the lung, liver, and intestine as evaluated by increase in myeloperoxidase (MPO) activity. Therefore, lipid peroxidation was significantly increased in zymosan-treated rats. This inflammatory process coincided with the damage of lung, liver, and small intestine. Immunohistochemical examination demonstrated a marked increase in the immunoreactivity to nitrotyrosine in the lung, liver, and small intestine of zymosan-shocked rats. HBO (2 absolute Atmosphere) exposure attenuates the increase in the tissue levels of MPO and malondialdehyde (MDA) caused by zymosan in the lung, liver, and intestine. In addition, HBO (2 absolute Atmosphere) was effective in preventing the development of lung, liver, and intestine injury. Taken together, the present results demonstrate that HBO may also be an efficacious treatment in multiple organ failure induced by zymosan.

Effect of hyperbaric oxygen therapy in experimental subcutaneous and pulmonary infections due to Pseudomonas aeruginosa

About 80% of nosocomial infections are caused by aerobic bacteria. Pseudomonas aeruginosa is a Gram-negative bacterium belonging to the Pseudomonadaceae family; P. aeruginosa is responsible for 6-22% of all hospital infections. The aim of this study was to evaluate the efficacy of hyperbaric oxygen (HBO2) therapy (2 atm abs x 55 min.day-1) alone for 8 days and combined with antibiotic chemotherapy (amikacin 15 mg.kg-1.day-1 for 8 days by intraperitoneal route) in rats infected subcutaneously and via the pulmonary route. In the rats infected by P. aeruginosa, HBO2 induced a reduction in mortality and morbidity with bacteria eradication in blood culture, bronchial aspirate, and skin biopsies when compared to control. These effects were increased by the use of amikacin, an antibiotic used for the treatment of sensitive Gram-negative bacteria.

Effects of hyperbaric oxygen exposure on a zymosan-induced shock model

OBJECTIVE

To evaluate the effects of hyperbaric oxygen (HBO) therapy on zymosan-induced shock in rats. Zymosan, a cell wall component of the yeast Saccharomyces cerevisiae, induces inflammation by causing the production of various cytokines and pro-inflammatory mediators. The administration of zymosan to rats represents a new experimental shock model by inducing acute peritonitis, severe hypotension, and signs of systemic illness. However, it has been recently proposed that the zymosan-induced shock, like septic shock, may be mediated by overproduction of nitric oxide.

DESIGN

Experimental study.

SETTING

Institute of Pharmacology and Toxicology, 2nd University of Naples, Naples, Italy.

SUBJECTS

Male rats were treated with zymosan (500 mg/kg) by intraperitoneal route, with HBO (2 Absolute Atmosphere) or with zymosan and HBO (2 Absolute Atmosphere).

MEASUREMENTS AND MAIN RESULTS

Peritoneal exudate, plasma, and peritoneal nitric oxide metabolites (NOx) and zymosan determined a time-dependent increase in peritoneal and plasma NOx concentrations, and peritoneal leukocytes were determined. Moreover, symptomatology was observed. The administration of zymosan caused the appearance of a severe illness in the rats characterized by ruffled fur, lethargy, conjunctivitis, diarrhea, and a significant loss of body weight. All zymosan-treated rats developed an acute peritonitis, producing turbid exudate. Zymosan determined a time-dependent increase in peritoneal, plasma NOx, and tumor necrosis factor (TNF)-alpha concentrations. Morbidity of zymosan shocked rats has been attenuated and no mortality was observed by treatment with HBO. These findings were associated with a significant reduction either of peritoneal leukocytes and exudate, or plasma and peritoneal NOx concentrations. Moreover, TNF-alpha levels were significantly reduced in animals shocked by zymosan and treated with HBO.

Somatic mutational mechanisms involved in intestinal tumor formation in Min mice

We have demonstrated previously that intestinal tumor formation in B6 Min/+ mice is always accompanied by loss of the wild-type adenomatous polyoposis coli (Apc) allele and that intestinal tumor multiplicity in B6 Min/+ mice can be significantly increased by treatment with a single dose of N-ethyl-N-nitrosourea (ENU). Here, we show that some tumors from ENU-treated Min/+ mice can form without complete elimination of Apc+. At least 25% of these tumors acquired somatic Apc truncation mutations. Interestingly, some ENU-induced tumors demonstrated loss of the Apc+ allelic marker examined by the quantitative PCR assay used here. Using two methods of mutation detection, we identified no Apc mutations in at least 12% of the tumors from ENU-treated B6 Min/+ mice. Finally, no H- or K-ras-activating mutations were detected in intestinal tumors from either untreated or ENU-treated Min/+ mice. The majority of somatic human APC mutations in intestinal tumors lead to APC truncation. Our results demonstrate that somatic Apc truncation mutations also frequently occur in ENU-induced intestinal tumors in Min mice.

Intestinal neoplasia in the ApcMin mouse: independence from the microbial and natural killer (beige locus) status

We have tested the hypothesis that enteric bacteria are necessary for formation of intestinal adenomas in C57BL/6-ApcMin/+ mouse. Germ-free mice developed 2-fold fewer adenomas than conventional controls in the medial small intestine (7.3 versus 14.9; P < 0.003), but there were no significant differences in the rest of the intestinal tract. We conclude that microbial status does not strongly alter the adenoma phenotype in this mouse model of familial adenomatous polyposis. In parallel, we have found that C57BL/6-ApcMin/+ mice mutated at the beige locus, which controls natural killer activity, are also unaltered in adenoma multiplicity.

Effects of hyperbaric oxygen exposure on non-adrenergic non-cholinergic responses of rat trachea

The effects of prolonged (20 day) hyperbaric exposure (HBO) to oxygen on non adrenergic non cholinergic (NANC) contractile and relaxant responses of rat trachea were examined. The electrical field stimulation (EFS) of rat tracheal rings was performed at 30 Hz and contractile and relaxant responses were assessed in the absence or in the presence of pretreatment with L-nitro-arginine-methyl-ester (L-NAME), an inhibitor of NO synthase, and L-Arginine (L-ARG), a precursor of NO synthesis, plus L-NAME. Our data demonstrated that L-NAME significantly (p < 0.05) enhanced the contractile responses induced by EFS (controls 30.6 +/- 0.99%; L-NAME 76.07 +/- 2.00%) and statistically (p < 0.05) reduced the relaxant component of EFS (controls 31.10 +/- 0.46; L-NAME 15.00 +/- 0.12); these effects were reversed when tissues were pretreated with L-ARG plus L-NAME, suggesting that NO plays a modulatory role in cholinergic neurotransmission and participates in EFS relaxant responses. Moreover, prolonged HBO exposure (20 days) at 202.6 and 303.9 kPa did not modify the contractile or relaxant responses induced by EFS, nor modify the L-NAME or L-ARG effects on EFS responses.

Concurrent overexpression of cyclin D1 and cyclin-dependent kinase 4 (Cdk4) in intestinal adenomas from multiple intestinal neoplasia (Min) mice and human familial adenomatous polyposis patients

We postulated that increased expression of the cell cycle regulators cyclin D1 and cyclin-dependent kinase (Cdk) 4 may be involved in the development of intestinal adenomas associated with familial adenomatous polyposis (FAP). In the present study of multiple intestinal neoplasia (Min) mice and human FAP patients, the expression and distribution of cyclin D1, Cdk4, and cell proliferative activity (5-bromo-2'-deoxyuridine incorporation) in normal and adenomatous intestinal epithelium were investigated. Immunohistochemical analysis of Min mouse intestine revealed that cyclin D1 immunoreactivity in the intestinal epithelium was restricted to the adenomatous areas, with a significantly higher percentage of positively staining nuclei in high-grade dysplasia versus low-grade dysplasia (54.8 +/- 18.4% versus 34.6 +/- 16.9%, P = 0.016). Morphologically normal areas of intestinal epithelia were uniformly negative for cyclin D1 immunoreactivity. Cdk4 nuclear immunoreactivity was restricted to the crypt areas in morphologically normal small intestine and colon. Conversely, Cdk4 immunoreactivity was uniformly abundant in adenomatous areas regardless of the degree of dysplasia. Increased expression of cyclin D1 and Cdk4 in adenomas was accompanied by a significantly increased 5-bromo-2'-deoxyuridine incorporation rate in the same areas. Immunoblot analysis of lysates from surgical specimens revealed increased levels of cyclin D1 and Cdk4 in the majority of intestinal adenomas from human FAP patients in comparison to the adjacent grossly normal colonic mucosa. Our results indicate that overexpression of cyclin D1 and Cdk4 occurs in intestinal adenomas and is associated with increased cell proliferative activity in premalignant neoplastic cells. Increased cyclin D1 immunoreactivity is associated with more severe dysplasia. These data suggest that abnormal up-regulation of these important G1 cell cycle proteins is a relatively early event in intestinal carcinogenesis and that these changes may contribute to malignant progression within those lesions.

Genetic evaluation of candidate genes for the Mom1 modifier of intestinal neoplasia in mice

As genetic mapping of quantitative trait loci (QTL) becomes routine, the challenge is to identify the underlying genes. This paper develops rigorous genetic tests for evaluation of candidate genes for a QTL, involving determination of allelic status in inbred strains and fine-structure genetic mapping. For the Mom1 modifier of intestinal adenomas caused by ApcMin, these tests are used to evaluate two candidate genes: Pla2g2a, a secretory phospholipase, and Rap1GAP, a GTPase activating protein. Rap1GAP passes the first test but is excluded by a single fine-structure recombinant. Pla2g2a passes both tests and is a strong candidate for Mom1. Significantly, we also find that ApcMin-induced adenomas remain heterozygous for the Mom1 region, consistent with Mom1 acting outside the tumor lineage and encoding a secreted product.

Somatic genetic events linked to the Apc locus in intestinal adenomas of the Min mouse

We have found previously that all spontaneous intestinal adenomas from Apc+/ApcMin mice lose the wild type Apc marker on two genetic backgrounds. On the (AKR x B6)F1 background, this event involves loss of the entire homolog of mouse chromosome 18 carrying Apc+. This chromosome carries both the Mcc and Dcc genes, which are homologs of genes that have been implicated in human colorectal cancer. To determine whether the loss of alleles of Mcc and/or Dcc is necessary for the formation of intestinal adenomas, subchromosomal somatic events were induced by gamma-irradiation. The observed spectrum of intrachromosomal somatic genetic losses rules out a requirement for loss of heterozygosity at either locus during adenoma formation. Subchromosomal allelic losses linked to Apc+ occur spontaneously on other genetic backgrounds. In the majority of these events, the Apc+ allele itself was somatically lost, as judged by the wild type marker at the Min site. However, on the [M. musculus castaneous (CAST) x B6-Min]F1 and (129/Sv x B6-Min)F1 backgrounds, spontaneous adenomas were observed in which the wild type marker at the Min site was retained. Further analysis will be required to determine whether these exceptions involve intra-Apc mutations. If not, then these events would illustrate routes to intestinal neoplasia that do not require complete inactivation of wild type Apc function.

Elevated cyclooxygenase-2 levels in Min mouse adenomas

BACKGROUND & AIMS

Mutations in the APC gene result in an increased propensity to develop intestinal neoplasia; however, a complete understanding of the mechanisms resulting in tumor formation has remained elusive. Min mice possess a mutation in the APC gene and display a neoplastic phenotype similar to that observed in familial adenomatous polyposis coli in humans. Cyclooxygenase (COX) inhibitors decrease tumor multiplicity in the Min mouse intestine. The present study was designed to determine if there was an increase in COX-2 in adenomas harvested from Min mouse intestine.

METHODS

COX-2 messenger RNA levels were determined by Northern blots and reverse-transcription polymerase chain reactions of B6Min x 129 mouse-derived tumors. Protein levels and localization were determined by Western blots and immunohistochemical staining.

RESULTS

The Northern blots revealed an approximately threefold increase in the level of COX-2 messenger RNA in Min mouse adenoma compared with normal mucosa. COX-2 protein levels in adenomatous tissues were also approximately threefold higher compared with normal mucosa from the same mouse. Immunohistochemical staining with a monospecific COX-2 antibody confirmed that increases in COX-2 immunoreactivity were restricted to dysplastic and neoplastic foci within intestinal mucosa.

CONCLUSIONS

These data show that COX-2 levels may be increased at an early stage in colorectal neoplasia during polyp formation and before invasion.

[Effects of hyperbaric oxygenation in skin and pulmonary infections caused by Pseudomonas aeruginosa]

About 80% of nosocomial infections are caused by aerobic bacteria. The Pseudomonas aeruginosa is a Gram-negative bacterium pertaining to the Pseudomonadaceae family. P. aeruginosa is responsible for 6-22% of all hospital infections. The aim of this paper is to evaluate the efficacy of both hyperbaric oxygen-therapy (HBO 2 Atm x 35 min/day) alone for 8 days and when associated to the chemoantibiotic therapy (amikacine 15 mg/kg/day for 8 days intraperitoneal), in rats infected through pulmonary and subcutaneous intake. In rats affected by P. aeruginosa, HBO induces a significant reduction in mortality and morbility with bacteria eradication in blood culture findings, bronchial aspirate and skin biopsies. These effects were increased by the use of amikacine which is an antibiotic used for the treatment of Gram-negative bacteria.

Influence of ozone on haemoglobin oxygen affinity in type-2 diabetic patients with peripheral vascular disease: in vitro studies

The use of ozone in the treatment of peripheral vascular disease (PVD) is increasing. The purpose of this study was to evaluate the effect of ozone on haemoglobin oxygen affinity in Type-2 diabetic patients with PVD. Twenty diabetic patients presenting with PVD (Clinical stage II-IV according to Fontaine) and 20 non-diabetic healthy matched subjects were studied. In both groups, aliquots of blood were ozonised with mixtures of oxygen-ozone (O2-O3) to reach end-concentrations of 6.5, 13, 26 and 78 micrograms O3 per ml of substrate. At baseline, diabetic patients presented significantly lower haemoglobin oxygen affinity values but higher plasma levels of free haemoglobin and malonyldialdehyde (MDA) than controls. In both diabetic patients and controls, exposure of blood to ozone reduced haemoglobin oxygen affinity in an "all-or-none" fashion, without changing 2-3, diphosphoglycerate concentrations in erythrocytes. Both free haemoglobin and MDA concentrations showed significant, dose-dependent increases after blood ozonisation. Thus, ozone caused a significant increase in oxygen unloading of haemoglobin in both normal subjects and Type-2 diabetic patients with PVD.

Homozygosity for the Min allele of Apc results in disruption of mouse development prior to gastrulation

Mutation of the APC (adenomatous polyposis coli) gene is an early event in colon tumor development in humans. Mice carrying Min (multiple intestinal neoplasia), a mutant allele of Apc, develop intestinal and mammary tumors as adults. To study the role of the Apc gene in development, we have investigated the phenotype of embryos homozygous for ApcMin (Min). Development of the primitive ectoderm fails prior to gastrulation in homozygous Min embryos. By midgestation, the presumed homozygotes consist of a mass of trophoblast giant cells with an additional cluster of much smaller embryonic cells. These results indicate that functional Apc is required for normal growth of inner cell mass derivatives.

ApcMin: a mouse model for intestinal and mammary tumorigenesis

Min (multiple intestinal neoplasia) is a mutant allele of the murine Apc (adenomatous polyposis coli) locus, encoding a nonsense mutation at codon 850. Like humans with germline mutations in APC, Min/+ mice are predisposed to intestinal adenoma formation. The number of adenomas is influenced by modifier loci carried by different inbred strains. One modifier locus, Mom-1 (modifier of Min-1), maps to distal chromosome 4. Intestinal tumours from both B6 (C57BL/6J) and hybrid Min/+ mice show extensive loss of the wild-type allele at Apc. B6 Min/+ female mice are predisposed to spontaneous mammary tumours. The incidence of both intestinal and mammary tumours can be increased in an age-specific manner by treatment with ethylnitrosourea (ENU). Min mice provide a good animal model for studying the role of Apc and interacting genes in the initiation and progression of intestinal and mammary tumorigenesis.

Hyperbaric oxygen, oxygen-ozone therapy, and rheologic parameters of blood in patients with peripheral occlusive arterial disease

For many years, clinical practice has consolidated the use of both hyperbaric oxygen and oxygen-ozone therapy in the treatment of peripheral occlusive arterial disease (POAD). We investigated the influence of these treatments on hemorrheologic parameters that play an important role in the pathogenesis and the clinical course of arteriosclerosis. Two groups of 15 patients suffering from POAD, assigned at random either to a cycle of HBO therapy or O2-O3 therapy, were evaluated for blood viscosity, erythrocyte filterability, hematocrit value, fibrinogen concentration, and thrombin time. The O2-O3 therapy caused a significant increase of erythrocyte filterability and a significant decrease of blood viscosity. By contrast, HBO therapy did not produce any significant change. The increase of lipid peri-oxidation, proved by raised malonyldialdehyde plasma levels, seems a likely mechanism involved in the hemorrheologic effects of O2-O3 therapy.

Loss of Apc+ in intestinal adenomas from Min mice

Allelic loss at the Apc locus in spontaneously occurring intestinal adenomas from mice heterozygous for the ApcMin nonsense mutation was analyzed using a site-specific quantitative polymerase chain reaction assay. All 97 of the intestinal adenomas analyzed showed extensive loss of the wild-type Apc (Apc+) allele. Quantitative polymerase chain reaction analysis of loci linked to Apc indicated loss of the chromosome carrying Apc+. Only one copy of the homologue carrying ApcMin remained in the intestinal adenomas. Possible reasons for the difference in the mechanism of Apc+ loss between human and Min mouse intestinal adenomas are discussed.

Genetic identification of Mom-1, a major modifier locus affecting Min-induced intestinal neoplasia in the mouse

Mutations in the human APC gene caused various familial colon cancer syndromes. The Multiple intestinal neoplasia (Min) mouse provides an excellent model for familial colon cancer: it carries a mutant mouse Apc gene and develops many intestinal adenomas. Here, we analyze how this tumor phenotype is dramatically modified by genetic background. We report the genetic mapping of a locus that strongly modifies tumor number in Min/+ animals. This gene, Mom-1 (Modifier of Min-1), maps to distal chromosome 4 and controls about 50% of genetic variation in tumor number in two intraspecific backcrosses. The mapping is supported by a LOD score exceeding 14. Interestingly, Mom-1 lies in a region of synteny conservation with human chromosome 1p35-36, a region of frequent somatic loss of heterozygosity in a variety of human tumors, including colon tumors. These results provide evidence of a major modifier affecting expression of an inherited cancer syndrome.

Mapping of multiple intestinal neoplasia (Min) to proximal chromosome 18 of the mouse

The Min (multiple intestinal neoplasia) mutation of the mouse has been mapped by analyzing the inheritance of restriction fragment length polymorphisms and simple sequence length polymorphisms in progeny from two intraspecific crosses segregating for the Min mutation. Min, a mutant allele of Apc, the mouse homolog of the human APC (adenomatous polyposis coli) gene, maps to proximal chromosome 18. The synteny between Apc and Mcc, the mouse homolog of the human MCC (mutated in colorectal cancer) gene, is conserved between mouse and human, although the gene order in the Apc to Mcc interval is different from that in the APC to MCC interval.

Multiple intestinal neoplasia caused by a mutation in the murine homolog of the APC gene

Germ-line mutations of the APC gene are responsible for familial adenomatous polyposis (FAP), an autosomal dominantly inherited disease in humans. Patients with FAP develop multiple benign colorectal tumors. Recently, a mouse lineage that exhibits an autosomal dominantly inherited predisposition to multiple intestinal neoplasia (Min) was described. Linkage analysis showed that the murine homolog of the APC gene (mApc) was tightly linked to the Min locus. Sequence comparison of mApc between normal and Min-affected mice identified a nonsense mutation, which cosegregated with the Min phenotype. This mutation is analogous to those found in FAP kindreds and in sporadic colorectal cancers.

[Hyperbaric oxygen therapy in the treatment of benign intracranial hypertension. Follow-up of a preliminary study]

Preliminary experience of hyperbaric oxygen (HBO) in the treatment of benign intracranial hypertension (BIH) is reported. Fifty-three patients with BIH were observed. They were treated with antiedema non steroid drugs plus rachicentesis, with steroid drugs plus rachicentesis, with lumbar peritoneal shunt and only 8 with HBO. Each patient underwent HBO with 100% oxygen at 2 atmospheres absolute a day for 15 days. In all patients a gradual disappearance of signs and symptoms of elevated intracranial pressure was observed. No lasting effect of treatment were seen after concluding therapy. The effect of HBO in the treatment of BIH has not yet been clarified, but the results can encourage further experience and studies.