COVID-19-associated cardiovascular morbidity in older adults: a position paper from the Italian Society of Cardiovascular Researches.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects host cells following binding with the cell surface ACE2 receptors, thereby leading to coronavirus disease 2019 (COVID-19). SARS-CoV-2 causes viral pneumonia with additional extrapulmonary manifestations and major complications, including acute myocardial injury, arrhythmia, and shock mainly in elderly patients. Furthermore, patients with existing cardiovascular comorbidities, such as hypertension and coronary heart disease, have a worse clinical outcome following contraction of the viral illness. A striking feature of COVID-19 pandemics is the high incidence of fatalities in advanced aged patients: this might be due to the prevalence of frailty and cardiovascular disease increase with age due to endothelial dysfunction and loss of endogenous cardioprotective mechanisms. Although experimental evidence on this topic is still at its infancy, the aim of this position paper is to hypothesize and discuss more suggestive cellular and molecular mechanisms whereby SARS-CoV-2 may lead to detrimental consequences to the cardiovascular system. We will focus on aging, cytokine storm, NLRP3/inflammasome, hypoxemia, and air pollution, which is an emerging cardiovascular risk factor associated with rapid urbanization and globalization. We will finally discuss the impact of clinically available CV drugs on the clinical course of COVID-19 patients. Understanding the role played by SARS-CoV2 on the CV system is indeed mandatory to get further insights into COVID-19 pathogenesis and to design a therapeutic strategy of cardio-protection for frail patients.

Conjugated polymers optically regulate the fate of endothelial colony-forming cells.

The control of stem and progenitor cell fate is emerging as a compelling urgency for regenerative medicine. Here, we propose a innovative strategy to gain optical control of endothelial colony-forming cell fate, which represents the only known truly endothelial precursor showing robust in vitro proliferation and overwhelming vessel formation in vivo. We combine conjugated polymers, used as photo-actuators, with the advantages offered by optical stimulation over current electromechanical and chemical stimulation approaches. Light modulation provides unprecedented spatial and temporal resolution, permitting at the same time lower invasiveness and higher selectivity. We demonstrate that polymer-mediated optical excitation induces a robust enhancement of proliferation and lumen formation in vitro. We identify the underlying biophysical pathway as due to light-induced activation of TRPV1 channel. Altogether, our results represent an effective way to induce angiogenesis in vitro, which represents the proof of principle to improve the outcome of autologous cell-based therapy in vivo.

Fine structural detection of calcium ions by photoconversion.

We propose a tool for a rapid high-resolution detection of calcium ions which can be used in parallel with other techniques. We have applied a new approach by  photo-oxidation of diaminobenzidine in presence of the emission of an excited fluorochrome specific for calcium detection. This method combines the selectivity of available fluorophores to the high spatial resolution offered by transmission electron microscopy to detect even fluorescing molecules even when present in low amounts in membrane-bounded organelles. We show in this paper that Mag-Fura 2 photoconversion via diaminobenzidine oxidation is an efficient way for localizing Ca2+ ions at EM level, is easily carried out and reproducible, and can be obtained on a good amount of cells, since the exposition in our conditions is not limited to the direct irradiation of the sample via an objective but obtained with a germicide lamp. The end product is sufficiently electron dense to be detected clearly when present in sufficient amount within a membrane boundary.

Differential clinical effects of different mutation subtypes in CALR-mutant myeloproliferative neoplasms.

A quarter of patients with essential thrombocythemia or primary myelofibrosis carry a driver mutation of CALR, the calreticulin gene. A 52-bp deletion (type 1) and a 5-bp insertion (type 2 mutation) are the most frequent variants. These indels might differentially impair the calcium binding activity of mutant calreticulin. We studied the relationship between mutation subtype and biological/clinical features of the disease. Thirty-two different types of CALR variants were identified in 311 patients. Based on their predicted effect on calreticulin C-terminal, mutations were classified as: (i) type 1-like (65%); (ii) type 2-like (32%); and (iii) other types (3%). Corresponding CALR mutants had significantly different estimated isoelectric points. Patients with type 1 mutation, but not those with type 2, showed abnormal cytosolic calcium signals in cultured megakaryocytes. Type 1-like mutations were mainly associated with a myelofibrosis phenotype and a significantly higher risk of myelofibrotic transformation in essential thrombocythemia. Type 2-like CALR mutations were preferentially associated with an essential thrombocythemia phenotype, low risk of thrombosis despite very-high platelet counts and indolent clinical course. Thus, mutation subtype contributes to determining clinical phenotype and outcomes in CALR-mutant myeloproliferative neoplasms. CALR variants that markedly impair the calcium binding activity of mutant calreticulin are mainly associated with a myelofibrosis phenotype.

Interleukin-6, soluble interleukin-6 receptor/interleukin-6 complex and insulin resistance in obese children and adolescents.

BACKGROUND/AIM: To study the characteristics of interleukin 6 (IL6), soluble form of interleukin 6 receptor (sILR)/IL6 complex in obese children and adolescents and its relationship with insulin resistance (IR). SUBJECTS AND METHODS: 66 obese children and adolescents [34 boys, mean age 10.3 ± 2.9 years, z-score of body mass index (BMI) 4.76 ± 1.36] and 24 non-obese healthy sex- and age-matched controls. Fasting levels of glucose, insulin, IL6, sIL6, sgp130 were measured. IR was assessed by homeostasis model assessment of IR (HOMA-IR). RESULTS: Obese subjects showed increased levels of insulin and IL-6 and higher HOMA-IR compared to controls (117.67 ± 50.9 vs. 62.42 ± 29.4 pmol/L, 2.73 ± 0.98 vs. 1.07 ± 0.41 pg/ml and 4.03 ± 2.16 vs. 1.83 ± 1.05 for insulin, IL-6 and HOMA-IR, respectively, p < 0.01 in all cases). sIL-6R levels were significantly lower in obese subjects (34.7 ± 14.2 vs. 55.6 ± 15.2 ng/ml in controls, p = 0.005), whereas sgp130 levels were not significantly different. In obese subjects, IL-6 directly correlated with z-score BMI (r = 0.481, p = 0.009) and with waist-to-height ratio (r = 0.494, p = 0.007), while sIL6-R was inversely related to HOMA-IR (r = -0.522, p = 0.002). Insulin resistant subjects showed higher levels of IL6 and lower levels of sIL6R (3.31 ± 0.72 vs. 2.25 ± 0.64 pg/ml, p = 0.020 and 25.3 ± 9.3 vs. 42.5 ± 10.4 ng/ml, p = 0.013, respectively). CONCLUSIONS: In obese children and adolescents, IR is associated with elevated levels of IL-6 and diminished values of sIL-6R.

Feasibility and effectiveness of primary umbilical hernia repair with biologic graft: preliminary study.

BACKGROUND: In this prospective non-randomized observational cohort study we evaluated: the feasibility and effectiveness of primary umbilical hernia repair with open tension-free and sutureless technique using a porcine small intestinal submucosa (Surgisis) prosthesis, the quality of the treatment in terms of reduction of postoperative discomfort and the complications at early and long-term follow-up. METHODS: Thirty-six consecutive patients, mean age 45.25 +/- 12.19 years, affected by primary umbilical uncomplicated hernia with a defect size < or = 3 cm, were treated in a day-surgery setting. A tailored flat Surgisis graft was used to ensure an overlap of at least 2 cm; in all patients the mesh was fixed by fibrin glue. Collected data included: visual analogic scale (VAS) pain scores at 24 hours, 72 hours, and 7, 15, and 30 days and number of analgesic medications after operation, complications rate, the quality of life measured by Short Form 36 health survey questionnaire (SF-36) before the operation and at long term follow-up. RESULTS: The mean follow-up time was 5.6 +/- 1.4 years. Postoperative pain was low: the mean visual analogic scale (VAS) scores were 2.8 at 24 h, 1.8 at 72 h, and 0.9, 0.3, and 0.04 at 7, 15, and 30 days, respectively. 77.8% of the patients (28/36) did not use any analgesic drugs. Seroma was reported in 13.8% of the patients (5/36); there were no hematomas, infection, chronic pain and no major complications or mortality (< or = 30 days). Recurrence rate was 2.8% (1/36). Patient satisfaction showed a significant improvement in all SF-36 domain scores (P < 0.001). CONCLUSIONS: The biologic mesh seems to be a safe and reliable device for repairing primary umbilical hernia with high patient comfort, even if not yet an alternative to synthetic mesh.

Endothelial remodelling and intracellular calcium machinery.

Rather being an inert barrier between vessel lumen and surrounding tissues, vascular endothelium plays a key role in the maintenance of cardiovascular homeostasis. The de-endothelialization of blood vessels is regarded as the early event that results in the onset of severe vascular disorders, including atherosclerosis, acute myocardial infarction, brain stroke, and aortic aneurysm. Restoration of the endothelial lining may be accomplished by the activation of neighbouring endothelial cells (ECs) freed by contact inhibition and by circulating endothelial progenitor cells (EPCs). Intracellular Ca(2+) signalling is essential to promote wound healing: however, the molecular underpinnings of the Ca(2+) response to injury are yet to be fully elucidated. Similarly, the components of the Ca(2+) toolkit that drive EPC incorporation into denuded vessels are far from being fully elucidated. The present review will survey the current knowledge on the role of Ca(2+) signalling in endothelial repair and in EPC activation. We propose that endothelial regeneration might be boosted by intraluminal release of specific Ca(2+) channel agonists or by gene transfer strategies aiming to enhance the expression of the most suitable Ca(2+) channels at the wound site. In this view, connexin (Cx) channels/hemichannels and store-operated Ca(2+) entry (SOCE) stand amid the most proper routes to therapeutically induce the regrowth of denuded vessels. Cx stimulation might trigger the proliferative and migratory behaviour of ECs facing the lesion site, whereas activation of SOCE is likely to favour EPC homing to the wounded vessel.

Epiphrenic diverticula mini-invasive surgery: a challenge for expert surgeons--personal experience and review of the literature.

BACKGROUND AND AIMS: While in the past, thoracotomy represented the traditional surgical approach for the treatment of epiphrenic diverticula, actually mini-invasive approach seems to be the preferred treatment as many series have been published in the recent years. This article describes the authors' experience with the laparoscopic approach for performing diverticulectomy, myotomy, and Nissen-Rossetti fundoplication. MATERIAL AND METHODS: From 1994 to 2010, 21 patients (10 men and 11 women), mean age 58.5 years (range 45-74 years), with symptomatic epiphrenic diverticulum underwent laparoscopic diverticulectomy, myotomy and Nissen-Rossetti fundoplication. RESULTS: The mean operative time was 135 min (range = 105-190 min). Mean hospital stay was 14.2 days (range = 7-25 days). In 5 patients (23.8%), a partial suture staple line leak was observed. Conservative treatment achieved leak resolution in all the cases. One patient (4.8%) died of a myocardial infarction in the postoperative period. After a mean clinical follow-up period of 78 months (range = 6-192 months), excellent or good outcome was referred with no dysphagia in 16 patients (80%) and only mild occasional dysphagia in 4 patients (20%). CONCLUSIONS: Surgical treatment of epiphrenic diverticula remains a challenging procedure also by mini-invasive approach, with major morbidity and mortality rates. For this reason, indications must be restricted only to selected and symptomatic patients in specialized centers.

A case of extraovarian primary peritoneal carcinoma in an oophorectomized-hysterectomized patient: a diagnostic dilemma.

Extra Ovarian Primary Peritoneal Carcinoma (EOPPC) is a rare type of adenocarcinoma of the pelvic and abdominal peritoneum. The objective examination and the histological aspect of the neoplasia virtually overlaps with that of ovarian carcinoma. The reported case is that of a 72 year-old patient who had undergone a total hysterectomy with bilateral annessiectomy surgery 20 years earlier subsequently to a diagnosis for uterine leiomyomatosis. The patient came to our attention presenting recurring abdominal pain, constipation, weight loss, severe asthenia and fever. Her blood test results showed hypochromic microcytic anemia and a remarkable increase CA125 marker levels. Instrumental diagnostics with Ultrasound (US) and CT scans indicated the presence of a single peritoneal mass (10-12 cm diameter) close to the great epiploon. The patient was operated through a midline abdominal incision and the mass was removed with the great omentum. No primary tumor was found anywhere else in the abdomen and in the pelvis. The operation lasted approximately 50 minutes. The post-operative course was normal and the patient was discharged four days later. The histological exam of the neoplasia, supported by immunohistochemical analysis, showed a significant positivity for CA 125, vimentin and cytocheratin, presence of psammoma bodies, and cytoarchitectural pattern resembling that of a serous ovarian carcinoma even in absence of primitiveness, leading to a final diagnosis of EOPPC. The patient later underwent six cycles of chemotherapy with paclitaxel (135 mg/m²/24 hr) in association with cisplatin (75mg/m²). At the fourth year follow-up no sign of relapse was observed.

Store-dependent Ca(2+) entry in endothelial progenitor cells as a perspective tool to enhance cell-based therapy and adverse tumour vascularization.

Endothelial progenitor cells (EPCs) have recently been employed in cell-based therapy (CBT) to promote neovascularization and regeneration of ischemic organs, such as heart and limbs. Furthermore, EPCs may be recruited from bone marrow by growing tumors to drive the angiogenic switch through physical engrafting into the lumen of nascent vessels or paracrine release of pro-angiogenic factors. CBT is hampered by the paucity of EPCs harvested from peripheral blood and suffered from several pitfalls, including the differentiation outcome of transplanted cells and low percentage of engrafted cells. Therefore, CBT will benefit from a better understanding of the signal transduction pathway(s) which govern(s) EPC homing, proliferation and incorporation into injured tissues. At the same time, this information might outline alternative molecular targets to combat tumoral neovascularization. We have recently found that store-operated Ca(2+) entry, a Ca(2+)-permeable membrane pathway that is activated upon depletion of the inositol-1,4,5-trisphosphate-sensitive Ca(2+) pool, is recruited by vascular endothelial growth factor to support proliferation and tubulogenesis in human circulating endothelial colony forming cells (ECFCs). ECFCs are a subgroup of EPCs that circulate in the peripheral blood of adult individuals and are able to proliferate and differentiate into endothelial cells and form capillary networks in vitro and contribute to neovessel formation in vivo. The present review will discuss the relevance of SOCE to ECFC-based cell therapy and will address the pharmacological inhibition of store-dependent Ca(2+) channels as a promising target for anti-angiogenic treatments.

ePTFE soft tissue patch reconstruction of hemidiaphragmatic agenesis with late clinical presentation.

In this paper we describe a case of a 71-year-old man affected by left hemidiaphragm agenesis who presented an extensive enterothorax after an asymptomatic history for many years. The patient had late development of severe constipation and occasional episodes of bowel obstruction and vomiting. The surgical correction of this congenital anomaly consisted of restoring the continuity of the diaphragmatic barrier with a 2-mm-thick expanded polytetrafluoroethylene soft tissue patch(Gore-Tex) after the herniated viscera have been replaced into the abdominal cavity. At 26 months' follow-up no recurrence has been observed. We would suggest that this is the first known elderly patient surgically treated and the eighth case reported in the literature. The use of a single-layer ePTFE mesh allows a good anatomical and functional repair. An overview of the literature is also reported.

Latrunculin A depolarizes starfish oocytes.

Depolymerization of the actin cytoskeleton may liberate Ca2+ from InsP3-sensitive stores in some cell types, including starfish oocytes, while inhibiting Ca2+ influx in others. However, no information is available on the modulation of membrane potential (V(m)) by actin. The present study was aimed to ascertain whether the widely employed actin depolymerizing drug, latrunculin A (Lat A), affects V(m) in mature oocytes of the starfish Astropecten aranciacus. Lat A induced a membrane depolarization which was mimicked by cytochalasin D, another popular actin disruptor, and prevented by jasplakinolide, a stabilizer of the actin network. Lat A-elicited depolarization consisted in a positive shift in V(m) which reached the threshold of activation of voltage-gated Ca2+ channels (VGCC), thus triggering an action potential. Lat A-promoted depolarization lacked the action potential in Ca2+-free sea water, while it was abolished upon removal of external Na+. Moreover, membrane depolarization was prevented by pre-injection of BAPTA and heparin, but not ryanodine. These data indicate that Lat A induces a membrane depolarization by releasing Ca2+ from InsP3Rs. The Ca2+ signal in turn activates a Ca2+-dependent Na+ entry, which causes the positive shift in V(m) and stimulates the VGCC.

Pharmacological characterization of NAADP-induced Ca2+ signals in starfish oocytes.

The recently discovered second messenger nicotinic acid adenine dinucleotide phosphate (NAADP) is central to the onset of intracellular Ca2+ signals induced by several stimuli, including fertilization. The nature of the Ca2+ pool mobilized by NAADP is still controversial. Depending on the cell type, NAADP may target either an acidic compartment with lysosomal properties or ryanodine receptors (RyRs) on endoplasmic reticulum. In addition, NAADP elicits a robust Ca2+ influx into starfish oocytes by activating a Ca2+-mediated current across the plasma membrane. In the present study, we employed the single-electrode intracellular recording technique to assess the involvement of either acidic organelles or RyRs in NAADP-elicited Ca2+ entry. We found that neither drugs which interfere with acidic compartments nor inhibitors of RyRs affected NAADP-induced depolarization. These data further support the hypothesis that a yet unidentified plasma membrane Ca2+ channel is the target of NAADP in starfish oocytes.

Feasibility of primary inguinal hernia repair with a new mesh.

BACKGROUND: The purpose of this study was to evaluate the feasibility of primary inguinal repair with open tension-free and sutureless technique using a new polypropylene "patch and plug system" (Prolene 3D patch), and the quality of the treatment in terms of reduction of postoperative discomfort. METHODS: Fifty-six consecutive patients, mean age 54.5+/-11.2 years, with primary unilateral uncomplicated inguinal hernia, were treated in a day-surgery setting. Collected data included: pain scores at 24 hours, 72 hours, and 7, 15, and 30 days after operation, analgesic medications, return to work and to heavy house and/or moderate sporting activities, and quality of life as measured by Short Form 36 health survey questionnaire (SF-36) before the operation and at 6 months follow-up. RESULTS: Postoperative pain was low: the mean visual analog scale (VAS) scores were 2.8 at 24 h, 1.8 at 72 h, and 0.9, 0.3, and 0.04 at 7, 15, and 30 days, respectively. Analgesic drugs were not used by 66.0% (n=37) of the patients. The mean global time to return to work and to heavy activities was 9.9+/-4.6 and 14.6+/-7.0, days, respectively. Patient satisfaction showed a significant improvement in all SF-36 domain scores at 6 months follow-up (P<0.001). There were no major complications, recurrences, or mortality. CONCLUSIONS: The new mesh seems to satisfy all requirements of a feasible, reliable, and effective device for repairing primary inguinal hernia with high patient comfort.

Expression and function of neuronal nicotinic ACh receptors in rat microvascular endothelial cells.

The expression and function of nicotinic ACh receptors (nAChRs) in rat coronary microvascular endothelial cells (CMECs) were examined using RT-PCR and whole cell patch-clamp recording methods. RT-PCR revealed expression of mRNA encoding for the subunits alpha(2), alpha(3), alpha(4), alpha(5), alpha(7), beta(2), and beta(4) but not beta(3). Focal application of ACh evoked an inward current in isolated CMECs voltage clamped at negative membrane potentials. The current-voltage relationship of the ACh-induced current exhibited marked inward rectification and a reversal potential (E(rev)) close to 0 mV. The cholinergic agonists nicotine, epibatidine, and cytisine activated membrane currents similar to those evoked by ACh. The nicotine-induced current was abolished by the neuronal nAChR antagonist mecamylamine. The direction and magnitude of the shift in E(rev) of nicotine-induced current as a function of extracellular Na(+) concentration indicate that the nAChR channel is cation selective and follows that predicted by the Goldman-Hodgkin-Katz equation assuming K(+)/Na(+) permeability ratio of 1.11. In fura-2-loaded CMECs, application of ACh, but not of nicotine, elicited a transient increase in intracellular free Ca(2+) concentration. Taken together, these results demonstrate that neuronal nAChR activation by cholinergic agonists evokes an inward current in CMECs carried primarily by Na(+), which may contribute to the plasma nicotine-induced changes in microvascular permeability and reactivity induced by elevations in plasma nicotine.

Ca2+ signalling and membrane current activated by cADPr in starfish oocytes.

Cyclic ADP-ribose (cADPr) is a second messenger that regulates intracellular free [Ca2+] ([Ca2+](i)) in a variety of cell types, including immature oocytes from the starfish Astropecten auranciacus. In this study, we employed confocal laser scanning microscopy and voltage clamp techniques to investigate the source of the cADPr-elicited Ca2+ wave originating from the cortical Ca2+ patches we have described previously. The Ca2+ swing was accompanied by a membrane current with a reversal potential of approximately +20 mV. Decreasing external Na+ almost abolished the current without affecting the Ca2+ response. Removal of extracellular Ca2+ altered neither the Ca2+ transient nor the ionic current, nor did the holding potential exert any effect on the Ca2+ wave. Both the Ca2+ response and the membrane current were abolished when BAPTA, ruthenium red or 8-NH(2)-cADPr were preinjected into the oocytes, while perfusion with ADPr did not elicit any [Ca2+](i) increase or ionic current. However, elevating [Ca2+](i) by uncaging Ca2+ from nitrophenyl- (NP-EGTA) or by photoliberating inositol 1,4,5-trisphosphate (InsP(3)) induced an ionic current with biophysical properties similar to that elicited by cADPr. These results suggest that cADPr activates a Ca2+ wave by releasing Ca2+ from intracellular ryanodine receptors and that the rise in [Ca2+](i) triggers a non-selective monovalent cation current that does not seem to contribute to the global Ca2+ elevation.

Activated M-phase-promoting factor (MPF) is exported from the nucleus of starfish oocytes to increase the sensitivity of the Ins(1,4,5)P3 receptors.

Starfish oocytes that are extracted from the ovaries are arrested at the prophase of the first meiotic division. At this stage of maturation, they are characterized by a large nucleus called the germinal vesicle. Meiosis resumption (maturation) can be induced in vitro by adding the hormone 1-methyladenine (1-MA) to the seawater in which the oocytes are suspended. Earlier work in our laboratory had detected Ca(2+) increases in both the cytoplasm and the nucleus of the oocytes approx. 2 min after the 1-MA challenge. The nuclear Ca(2+) increase was found to be essential for the continuation of the meiotic cycle, since the injection of bis-(o-aminophenoxy)ethane- N,N,N',N' -tetra-acetic acid (BAPTA) into the nuclear compartment completely blocked the re-initiation of the cell cycle. We have recently confirmed, using confocal microscopy, that the cytoplasmic and nuclear Ca(2+) pools are regulated independently and that the nuclear envelope in starfish oocytes is not freely permeated by the Ca(2+) wave that sweeps across the nuclear region. Studies by others have shown that the sensitivity of the Ins(1,4,5) P (3) (IP(3)) receptors (IP(3)Rs) to IP(3) increases during oocyte maturation, so that they release progressively more calcium in response to the injection of IP(3), as maturation proceeds. We have now shown that the increased sensitivity of the IP(3)Rs may depend on the activation of the cyclin-dependent kinase, MPF (M-phase-promoting factor) that occurs in the nucleus. MPF does not directly phosphorylate IP(3)Rs but phosphorylates instead the actin-binding protein actin depolymerization factor (ADF)/cofilin.

P2y1 and P2y2 receptor-operated Ca2+ signals in primary cultures of cardiac microvascular endothelial cells.

Intracellular Ca2+ signals elicited by nucleotide agonists were investigated in primary cultures of rat cardiac microvascular endothelial cells using the fura-2 technique. UTP increased the intracellular [Ca2+] in 94% of the cells, whereas 2MeSATP was active in 32%. The rank order of potency was ATP = UTP > 2MeSATP and the maximal response to 2MeSATP was lower compared to UTP and ATP. ATP and UTP showed strong homologous and heterologous desensitization. ATP fully inhibited the 2MeSATP response, while UTP abolished 2MeSATP-elicited transients in 25% of cells. 2MeSATP did not desensitize the UTP or ATP response. Adenosine 2',5'-diphosphate inhibited the response to 2MeSATP, while it did not modify the response to ATP and UTP. 2MeSATP was more sensitive to suramin than UTP and ATP. These results indicate that P(2Y1) and P(2Y2) receptors may be coexpressed in CMEC. Nucleotide-induced Ca2+ signals lacked a sustained plateau and were almost independent from extracellular Ca2+. ATP and UTP elicited Ca2+ transients longer than 2MeSATP-evoked transients. The kinetics of Ca2+ responses was not affected by bath solution stirring or ectonucleotidase inhibition. Furthermore, the nonhydrolyzable ATP analogue AMP-PNP induced Ca2+ signals similar to those elicited by ATP and UTP. These results suggest that the distinct kinetics of nucleotide-evoked Ca2+ responses do not depend on the activity of ectonucleotidases or ATP autocrine stimulation. The possibility that Ca2+ signals with different time courses may modulate different cellular responses is discussed.

Autoimmune hemolytic anemia in chronic hepatitis C virus infection: an unusual extrahepatic autoimmune manifestation.

We report a case of Coombs positive autoimmune hemolytic anemia occurring in a patient with chronic hepatitis C, never treated with interferon-alpha. Prednisone treatment induced the complete remission of both clinical and hematological findings after 2 months. The indirect Coombs test turned negative, while the direct Coombs test remained weakly positive. Autoimmune hemolytic anemia during chronic hepatitis C has been reported to develop only after or simultaneously with interferon-alpha therapy. After discarding other possible causes such as drugs, infectious, neoplastic, lymphoproliferative diseases, and essential mixed cryoglobulinemia, we made the hypothesis of a correlation between autoimmune hemolytic anemia and hepatitis C virus infection.