BACKGROUND: The aim of this study is to report our results with carotid body tumor (CBT) surgical management. METHODS: Between 2010 and 2018, 100 CBTs (mean age: 48.0 years, range 21-80 years old) were treated in our center. The patients were classified in 3 groups according to the size: group I (<3 cm), group II (3 to 5 cm) and group III (>5 cm). RESULTS: Surgical resection was performed in 88 patients and conservative treatment in 2 cases. Nine patients were treated for bilateral involvement and one of them was also treated again for a relapse. Postoperatively, cranial nerve injury (CNI) was significantly higher in group II [3 (8.3%) vs. 16 (31.4%) vs. 2 (15.4%); P=0.030] with no statistical differences between the CN involved. At univariate analysis for CNI, CBT group (P=0.030), maximum diameter (P=0.046), patients presenting with dysphonia (P=0.035) and dysphagia (P=0.007) and patients suffering from any intraoperative complication (P=0.047) were statistically significant. At multivariate analysis the only significant variable was CBT group II (P=0.016). For blood loss, CBT group III (P<0.001), Shamblin class III (P<0.001), Pulmonary disease (P=0.034) and surgery time (P<0.001) were statistically significant. The follow-up of 79 patients (87.8%) showed a 100% overall survival at median follow-up of 37.7 months (range 2-84.7 months) with freedom from local recurrence of 97.8% (77/79); CONCLUSIONS: Surgical resection remains the gold standard to obtain complete recovery, although tumor size is to be considered a risk factor for CNI because large CBTs remain at high risk for CNIs.

Alteration of circulating T-cell subpopulations may reflect the local immune process in plaques [(1)][1], providing insights on atherosclerosis pathogenesis. Only limited knowledge concerning the relationship between circulating lymphocytes and features of atherosclerotic lesions is available [(2

Pol zeta is an error-prone DNA polymerase that is critical for embryonic development and maintenance of genome stability. To analyze its suggested role in somatic hypermutation (SHM) and possible contribution to DNA double-strand break (DSB) repair in class switch recombination (CSR), we ablated Rev3, the catalytic subunit of Pol zeta, selectively in mature B cells in vivo. The frequency of somatic mutation was reduced in the mutant cells but the pattern of SHM was unaffected. Rev3-deficient B cells also exhibited pronounced chromosomal instability and impaired proliferation capacity. Although the data thus argue against a direct role of Pol zeta in SHM, Pol zeta deficiency directly interfered with CSR in that activated Rev3-deficient B cells exhibited a reduced efficiency of CSR and an increased frequency of DNA breaks in the immunoglobulin H locus. Based on our results, we suggest a nonredundant role of Pol zeta in DNA DSB repair through nonhomologous end joining.

Chlamydia Pneumoniae (CP) infection is strongly associated with coronary artery disease, as well as with atherosclerosis of the carotid and peripheral arteries. However, the role of CP in the pathogenesis of aortic disease remains controversial. Our present experience suggests no correlation between a current infection with C. pneumoniae and acute aortic dissection. Well-designed large prospective studies are needed in order to clarify the pathophysiologic role of CP infection in acute and chronic aortic disease.

Protrusion of stent-grafts into adjacent structures is an uncommon but life-threatening complication of endovascular procedures and may result in fistulization. Tracheoinnominate fistulization is a devastating and often fatal condition, requiring prompt diagnosis and appropriate surgical treatment.1Courcy P.A. Rodriguez A. Garrett H.E. Operative technique for repair of tracheoinnominate artery fistula.J Vasc Surg. 1985; 2: 332-334PubMed Scopus (12) Google Scholar This report describes a case of a tracheoinnominate fistula as a delayed complication of a posttraumatic pseudoaneurysm endovascular repair. A 21-year-old Asian man with a 5-cm posttraumatic pseudoaneurysm of the innominate artery was treated at the referring hospital by implantation of three covered stents from the origin of the innominate artery to the proximal tract of the right common carotid artery. Postoperative computed tomographic scans showed complete pseudoaneurysm exclusion and right subclavian artery occlusion at the origin, reperfused by the right vertebral artery. The postoperative course was complicated by a tracheal ring laceration (requiring endoscopic toilet and tracheostomy), pulmonary infection, and sepsis. The patient was given antibiotic therapy and discharged in stable conditions. Two months later, a scheduled fiberbronchoscopy, followed by magnetic resonance imaging of the chest, showed erosion of stent-grafts into the tracheal lumen for a 3-cm long segment, with multiple ulcerations of the right lateral wall. The patient was transferred to our institution for further treatment. On the first day, he had several episodes of hemoptysis. Preoperative imaging confirmed protrusion of the stent-grafts into the tracheal lumen (Figure 1). The patient underwent right cervicosternotomy and surgical exploration of the cervicothoracic region. A fistula was found between the innominate artery, where the stent-grafts had been placed, and the trachea. The grafts seemed also to be excessively oversized relative to the artery diameter. We proceeded to excision of the innominate artery and stent-grafts, extra-anatomic cerebral revascularization (through a left-to-right common carotid artery crossover bypass with a 6-mm expanded polytetrafluoroethylene ringed graft), and tracheal reconstruction with an autologous patch of thymus, pericardium, and arterial wall. Despite initial hemodynamic stability, hemothorax, hemopericardium, and massive hemoptysis developed in the postoperative period as a result of active bleeding from the innominate artery stump. Consequently, the patient underwent hypothermic cardiac arrest and urgent resternotomy. The aortic arch wall was found to be lacerated and was sutured with a bovine pericardial patch (Figure 2). Dehiscence of tracheal reconstruction was treated by sealing a pedicled left internal thoracic artery, parietal pleura, and pectoralis major muscle flap. Three days later, the patient underwent a new surgical operation under deep hypothermic circulatory arrest for septic necrosis of the tracheal reconstruction. A few days later, a new episode of massive bleeding occurred, leading to hemorrhagic shock and death. Tracheal erosion by a vascular graft has been previously described only by Conklin and coworkers2Conklin L.D. LeMaire S.A. Casar G.J. Coselli J.S. Tracheal erosion by an innominate artery graft: presentation and surgical repair.Ann Thorac Surg. 2003; 75: 573-575Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar in a patient who underwent graft reconstruction of the innominate artery for a mycotic pseudoaneurysm. In recent years, endovascular procedures have been performed with increasing frequency for the treatment of traumatic injuries of the supra-aortic trunks, especially of the innominate artery,3Diaz-Daza O. Arraiza F.J. Barkley J.M. Whigham C.J. Endovascular therapy of traumatic vascular lesions of the head and neck.Cardiovasc Intervent Radiol. 2003; 26: 213-221Crossref PubMed Scopus (58) Google Scholar because they are considered minimally invasive and relatively easy to carry out. No documentation is yet available, however, regarding long-term results and specific delayed complications. The complication we observed was probably due either to oversized stent-grafts and multiple stent-grafts overlapping. It is well known that endograft diameter must be oversized between 10% and 20% relative to the estimated proximal neck diameter and that the graft length must be correctly selected to avoid multiple stent-grafts overlapping.3Diaz-Daza O. Arraiza F.J. Barkley J.M. Whigham C.J. Endovascular therapy of traumatic vascular lesions of the head and neck.Cardiovasc Intervent Radiol. 2003; 26: 213-221Crossref PubMed Scopus (58) Google Scholar It is also important to evaluate the integrity of the vessel’s wall and the sterility of anatomic district affected by the trauma or infection. Treatment of tracheoinnominate fistula as a result of stent-graft erosion is surgical and requires excision of the innominate artery and separation from the trachea.2Conklin L.D. LeMaire S.A. Casar G.J. Coselli J.S. Tracheal erosion by an innominate artery graft: presentation and surgical repair.Ann Thorac Surg. 2003; 75: 573-575Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar The best access for exposure of the proximal innominate artery and of the trachea is through a midline sternotomy. In the presence of active bleeding, a femorofemoral cardiopulmonary bypass could be installed and deep hypothermic circulatory arrest obtained before opening the chest. The innominate artery should be cut close to its origin on the aortic arch and the trachea sewn with interposition of pleural or pericardial patch.4Gasparri M.G. Nicolosi A.C. Almassi G.H. A novel approach to the management of tracheoinnominate artery fistula.Ann Thorac Surg. 2004; 77: 1424-1426Abstract Full Text Full Text PDF PubMed Scopus (18) Google Scholar The revascularization of cerebral and brachial arteries is preferably obtained by extra-anatomic reconstruction. In our case, the best option to protect the brain before treating the innominate artery was retropharyngeal carotid–carotid crossover bypass. In conclusion, the treatment of traumatic injuries of the innominate artery could be either surgical or endovascular. It is important to select correct materials and to avoid postoperative infection that could lead to a tracheoinnominate fistula. This occurrence represents a dangerous complication, requiring surgical treatment with extra-anatomic bypass grafting, excision of the innominate artery, and reconstruction of the trachea with autologous tissue.4Gasparri M.G. Nicolosi A.C. Almassi G.H. A novel approach to the management of tracheoinnominate artery fistula.Ann Thorac Surg. 2004; 77: 1424-1426Abstract Full Text Full Text PDF PubMed Scopus (18) Google Scholar Drs Brioschi, Esposito, Marone, Tshomba, Prof Chiesa, and Dr Kahlberg (left to right)

Monoallelic demethylation and rearrangement control allelic exclusion of the immunoglobulin kappa-chain locus (Igk locus) in B cells. Here, through the introduction of pre-rearranged Igk genes into their physiological position, the critical rearrangement step was bypassed, thereby generating mice producing B cells simultaneously expressing two different immunoglobulin-kappa light chains. Such 'double-expressing' B cells still underwent monoallelic demethylation at the Igk locus, and the demethylated allele was the 'preferred' substrate for somatic hypermutation in each cell. However, methylation itself did not directly inhibit the activation-induced cytidine-deaminase reaction in vitro. Thus, it seems that the epigenetic mechanisms that initially bring about monoallelic variable-(diversity)-joining rearrangement continue to be involved in the control of antibody diversity at later stages of B cell development.

We previously demonstrated that male mice deficient in the soluble adenylyl cyclase (sAC) are sterile and produce spermatozoa with deficits in progressive motility and are unable to fertilize zona-intact eggs. Here, analyses of sAC−/− spermatozoa provide additional insights into the functions linked to cAMP signaling. Adenylyl cyclase activity and cAMP content are greatly diminished in crude preparations of sAC−/− spermatozoa and are undetectable after sperm purification. HCO3− is unable to rapidly accelerate the flagellar beat or facilitate evoked Ca2+ entry into sAC−/− spermatozoa. Moreover, the delayed HCO3−-dependent increases in protein tyrosine phosphorylation and hyperactivated motility, which occur late in capacitation of wild-type spermatozoa, do not develop in sAC−/− spermatozoa. However, sAC−/− sperm fertilize zona-free oocytes, indicating that gamete fusion does not require sAC. Although ATP levels are significantly reduced in sAC−/− sperm, cAMP-AM ester increases flagellar beat frequency, progressive motility, and alters the pattern of tyrosine phosphorylated proteins. These results indicate that sAC and cAMP coordinate cellular energy balance in wild-type sperm and that the ATP generating machinery is not operating normally in sAC−/− spermatozoa. These findings demonstrate that sAC plays a critical role in cAMP signaling in spermatozoa and that defective cAMP production prevents engagement of multiple components of capacitation resulting in male infertility.

Hand and wrist aneurysms are a rare pathology, but recently the number of cases is increasing because of iatrogenic injuries such as catheter placement for endovascular procedures, invasive blood pressure monitoring, and arterial blood collection. In the period between January 1992 and January 2005, seven patients were treated at our institution for hand and wrist aneurysms. Five were true aneurysms and two were false aneurysms. All patients underwent surgery: four had aneurysmectomy and ligation of the arterial stumps and three had lesion removal, with arterial break suture in two cases and reconstruction with interposition of reversed autologous vein in the other case. In all cases, we did not have any postoperative ischemic or neurological complications. Symptoms like pain, paresthesia, and disesthesia combined with the minimal morbidity associated with repair suggest that operative repair of these aneurysms should be routinely performed.

To acquire the ability to fertilize, spermatozoa undergo complex, but at present poorly understood, activation processes. The intracellular rise of cAMP produced by the bicarbonate-dependent soluble adenylyl cyclase (sAC) has been suggested to play a central role in initiating the cascade of the events that culminates in spermatozoa maturation. Here, we show that targeted disruption of the sAC gene does not affect spermatogenesis but dramatically impairs sperm motility, leading to male sterility. sAC mutant spermatozoa are characterized by a total loss of forward motility and are unable to fertilize oocytes in vitro. Interestingly, motility in sAC mutant spermatozoa can be restored on cAMP loading, indicating that the motility defect observed is not caused by a structural defect. We, therefore, conclude that sAC plays an essential and nonredundant role in the activation of the signaling cascade controlling motility and, therefore, in fertility. The crucial role of sAC in fertility and the absence of any other obvious pathological abnormalities in sAC-deficient mice may provide a rationale for developing inhibitors that can be applied as a human male contraceptive.

Somatic hypermutation in B cells undergoing T cell dependent immune responses generates high affinity antibodies that provide protective immunity. B cells also switch from the expression of immunoglobulin (Ig) M and IgD to that of other Ig classes through somatic DNA recombination. Recent work has implicated DNA strand breaks, possibly DNA double strand breaks (DSB), as the initiating lesions in both class switch recombination and hypermutation, although the etiology of these lesions is not understood. Spo11, a protein structurally related to archaeal type II topoisomerases, generates DSB that initiate meiotic recombination. This characteristic, together with its expression pattern, marks this enzyme as a potential candidate for the initiation of hypermutation, and perhaps also for Ig class switching. To investigate whether Spo11 is involved in these processes, we studied the T cell dependent immune response of Spo11-deficient (Spo11(-/-)) mice against the hapten nitrophenyl (NP). We found that V186.2-bearing IgG1 transcripts had normal levels and patterns of somatic hypermutation. Furthermore, Spo11(-/-) mice showed normal serum levels of all Ig isotypes. These results indicate that Spo11 is not required for Ig hypermutation or class switch recombination.

Somatic hypermutation (SH) in B cells undergoing T cell-dependent immune responses generates high-affinity antibodies that provide protective immunity. Most current models of SH postulate the introduction of a nick into the DNA and subsequent replication-independent, error-prone short-patch synthesis by one or more DNA polymerases. The PolK (DinB1) gene encodes a specialized mammalian DNA polymerase called DNA polymerase kappa (polkappa), a member of the recently discovered Y family of DNA polymerases. The mouse PolK gene is expressed at high levels in the seminiferous tubules of the testis and in the adrenal cortex, and at lower levels in most other cells of the body including B lymphocytes. In vitro studies showed that polkappa can act as an error-prone polymerase, although they failed to ascribe a clear function to this enzyme. The ability of polkappa to generate mutations when extending primers on undamaged DNA templates identifies this enzyme as a potential candidate for the introduction of nucleotide changes in the immunoglobulin (Ig) genes during the process of SH. Here we show that polkappa-deficient mice are viable, fertile and able to mount a normal immune response to the antigen (4-hydroxy-3-nitrophenyl)acetyl-chicken gamma-globulin (NP-GC). They also mutate their Ig genes normally. However, polkappa-deficient embryonic fibroblasts are abnormally sensitive to killing following exposure to ultraviolet (UV) radiation, suggesting a role of polkappa in translesion DNA synthesis.

The ubiquitously expressed, error-prone DNA polymerase beta (polbeta) plays a role in base excision repair, and the involvement of this molecule in the nonhomologous end joining (NHEJ) process of DNA repair has recently been demonstrated in yeast. Polbeta-deficient mice are not viable, and studies on conditional mutants revealed a competitive disadvantage of polbeta(-/-) vs. wild-type cells. We show here that polbeta-deficient mice survive up to day 18.5 postcoitum, but die perinatally; a circumstance that allowed the investigation of a potential role of polbeta in lymphocyte development by transfer of fetal liver cells (FLC) derived from polbeta(-/-) embryos into lethally irradiated hosts. FLC transfers using mutant cells lead to an almost normal reconstitution of the lymphocyte compartment, indicating that polbeta-deficiency does not prevent V(D)J recombination, which is known to employ factors of the NHEJ pathway. Mice reconstituted with polbeta(-/-) FLC mount a normal T cell-dependent immune response against the hapten (4-hydroxy-3-nitrophenyl) acetyl (NP). Moreover, germinal center B cells from NP-immunized reconstituted mice show normal levels and patterns of somatic point mutations in their rearranged antibody genes, demonstrating that polbeta is not critically involved in somatic hypermutation.

Polymerase zeta (Pol zeta) is an error-prone DNA polymerase [1], which in yeast is involved in trans-lesion synthesis (TLS) and is responsible for most of the ultraviolet (UV) radiation-induced and spontaneous mutagenesis [2-4]. Pol zeta consists of three subunits: REV1, a deoxycytidyl-transferase [5]; REV7, of unclear function [6]; and REV3, the catalytic subunit. REV3 alone is sufficient to carry out TLS, but association with REV1 and REV7 enhances its activity [5, 7]. Experiments using human cells treated with UV radiation indicate also that mammalian Pol zeta is involved in TLS [7]. The peculiar mutagenic activity of Pol zeta [4,7,8] suggests a possible role in somatic hypermutation of immunoglobulin (Ig) genes [9]. Here, we report that, unlike in yeast where the REV3 gene is not essential for life [4], disruption of the mouse homologue (Rev3l) resulted in early embryonic lethality. In Rev3l(-/-) embryos, no haematopoietic cells other than erythrocytes could be identified in the yolk sac. Rev3l(-/-) haematopoietic precursors were unable to expand in vitro and no haematopoietic cells could be derived from the intraembryonic haematogenic compartment (splanchnopleura). Fibroblasts could not be derived from the Rev3l(-/-) embryos, and Rev3l(-/-) embryonic stem (ES) cells could not be obtained. This is the first evidence that an enzyme involved in TLS is critical for mammalian development.

The presence of Chlamydia pneumoniae in atheromas has been demonstrated in several studies. Culture of the organism from arterial tissue has been difficult. We report the use of a reverse transcriptase polymerase chain reaction to detect viable Chlamydia pneumoniae in carotid atheromas. We analyzed 30 patients (14 females, mean age 69.6 +/- 8.8 years) who underwent surgery for the removal of atherosclerotic plaques from carotid arteries. During surgery, samples of lingual vein and superior thyroideal artery were also taken. We applied two molecular biology techniques to the carotid plaques on lingual vein or thyroideal artery samples: 1) polymerase chain reaction (PCR) and 2) reverse transcriptase-PCR (RT-PCR) for the detection of bacterial mRNA, employing PCR primers designed to detect a fragment of the 16S rRNA gene. Blood samples were obtained from the patients for determination of Chlamydia pneumoniae IgG, IgA, and IgM antibody titers by a microimmunofluorescence technique. The results of the present study confirmed the presence of viable Chlamydia pneumoniae in atheromas and support the hypothesis that the organism may be an active factor in the pathogenesis of atherosclerosis.

In this paper we demonstrate that phage display technology is a suitable system for studying the interaction between the high-affinity receptor for IgE (FcϵRI) and IgE. The α subunit extracellular domains of the human receptor were expressed on the surface of filamentous phage M 13 fused to the carboxyl-terminal part of the gene III protein (pIII). Two constructs were made, the first with both the Ig-like domains of the receptor α chain and the second with only the C-terminal domain. The fusion genes were cloned in a phagemid vector to display monovalently the receptor on the phage surface. Our results indicate that the α receptor expressed on the phage is able to interact with IgE as demonstrated by an ELISA assay. In addition, by using the same system, we show that a single domain of the α receptor is sufficient for the interaction with IgE although with a binding affinity lower than that of the two-domain receptor.

In this paper we demonstrate that phage display technology is a suitable system for studying the interaction between the high‐affinity receptor for IgE (FcϵRI) and IgE. The α subunit extracellular domains of the human receptor were expressed on the surface of filamentous phage M 13 fused to the carboxyl‐terminal part of the gene III protein (pIII). Two constructs were made, the first with both the Ig‐like domains of the receptor α chain and the second with only the C‐terminal domain. The fusion genes were cloned in a phagemid vector to display monovalently the receptor on the phage surface. Our results indicate that the α receptor expressed on the phage is able to interact with IgE as demonstrated by an ELISA assay. In addition, by using the same system, we show that a single domain of the α receptor is sufficient for the interaction with IgE although with a binding affinity lower than that of the two‐domain receptor.