Current development of lentiviral-mediated gene transfer

Lentiviral-based vectors have been widely used lately in preclinical studies and for the in vitro genetic manipulation of embryonic and adult stem cells. They allow for the transduction of nondividing cells and for stable gene expression. On these grounds, lentiviral vectors look promising for eventual applications for the gene-based treatment of neurological disorders, cardiopathies and inherited or acquired genetic diseases. The best developed and characterized lentiviral vector system is based on the human immunodeficiency virus type 1 (HIV-1). However, safety concerns preclude any possible application of HIV-1-derived vectors in clinical trials. For this reason, gene therapists are currently improving the design of other lentiviral vectors, such as feline immunodeficiency virus, equine anemia infectious virus and Visna virus. These lentiviruses are not pathogenic in humans and are only distantly related to primate Retroviridae. This review summarizes the achievements in improving the design of lentiviral vector systems that are not based on HIV-1.

Surgical treatment of haemorrhoidal disease: a survey of the regional area of Campania in Italy

INTRODUCTION

In order to monitor the common practice regarding the surgical treatment of haemorrhoidal disease in Campania, a region in the South of Italy, a survey amongst one hundred specialists in general surgery and members of the Neapolitan Surgery Association (S.Na.C.) was carried out.

MATERIALS AND METHODS

The survey was carried out through a 13-items questionnaire sent to 100 General Surgeons working in Campania. The survey sample was chosen randomly from the S.Na.C. members. Participants were given two weeks to fill in and return the questionnaire.

RESULTS

The survey, was developed to obtain a "picture" of the current situation and revealed some interesting results: the procedure preferred was the Milligan and Morgan Haemorrhoidectomy (MMH) being used in 41% of the cases, whilst stapled haemorrhoidopexy (SH) was carried out only in 19% of the cases and 44.4% of the surgeons never carried even one. With regard to postoperative complications, bleeding was the most common after SH which occurred in 10 out of 260 cases (3.8%), whereas anal pain was the most common after MMH (179%).

DISCUSSION

In keeping with the literature the analysis shows that, although fairly good results with low complication rates are reported with SH, it is still not widely accepted and is performed in only 19% of the patients in our Regional area.

Disappointing long-term results of the artificial anal sphincter for faecal incontinence

Long term results of ABS disappointing

Surveillance of post-operative infections and management of antibiotic surgical prophylaxis in an Italian region

The aim of the study was to evaluate the incidence of post-surgical infections and to assess management of antibiotic surgical prophylaxis. The survey was carried out by means of a questionnaire in order to obtain diverse information such as demographics, length of pre- and post-operative hospitalization, type of surgery, intervention duration, possible antibiotic prophylaxis and onset of post-surgical infections also monitored by post-discharge ambulatory controls. Four General Surgery and five Obstetrics and Gynecology Departments in Campania (southern Italy) participated in the study, which was carried out from December 2001-January 2002. Overall, 410 questionnaires were collected, referring to as many patients; antibiotic prophylaxis was performed in 385 (93.9%) patients. Antibiotic prophylaxis was generally managed not according to the general principles suggested by the international guidelines either for timing, for its duration or for the route of administration. Substantial differences were also noted in patient selection and antibiotic choice. Surgical site infections were recorded in 0.9% of patients undergoing clean surgery and in 3.6% of patients undergoing clean-contaminated surgery. Distant infections occurred in 1.5% in clean-contaminated surgery. The results of the present study suggest the need for continuous and accurate monitoring of post-surgical infections and the need to adopt appropriate guidelines to improve the management of surgical prophylaxis.

Pilot study on prevention of lung injury during surgery for type A acute aortic dissection: no evident improvements with celsior flushing through the pulmonary artery

OBJECTIVE

Postoperative respiratory failure is a frequent and serious complication in patients with type A acute aortic dissection. Experimental evidence suggests that pulmonary artery perfusion using hypothermic protective solutions helps prevent lung injury. The aim of this pilot prospective study was to evaluate the effect of pulmonary artery flushing during selective cerebral perfusion (SCP) on lung function.

METHODS

Twenty patients referred for acute type A aortic dissection, who were free from preoperative respiratory dysfunction, were assigned prospectively and alternately to two treatment groups. Pulmonary flushing was performed during SCP in group P (10 patients), while conventional Kazui technique was applied in group N (10 patients). Lung perfusion consisted of single-shot hypothermic pulmonary artery flush with Celsior. Lung function was evaluated by intubation time, scoring of chest radiograms at 12 hours after CPB, and PaO2/FiO2 assessed from immediately before surgery to 72 hours after termination of cardiopulmonary bypass.

RESULTS

Incidence of pre, intra and post operative determinants of lung dysfunction proved homogeneous in both groups. Lung oxygenation function showed a marked post operative decline followed by a slow improvement in both groups. Analysis of respiratory ratios did not disclose significant differences even though the flushed group had a better performance in all study patients. The incidence of prolonged ventilator support (longer than 72 hours) (30% vs 20%, p = NS) and severity of x-ray pulmonary infiltrate score were comparable (mean score 1.7 +/- 0.71 vs 1.6 +/- 0.68, p = NS).

CONCLUSIONS

Pulmonary artery flushing with Celsior solution does not seem to provide an effective preservation of lung function.

Efficacy and limitations of preemptive therapy against cytomegalovirus infections in heart transplant patients

OBJECTIVES

Cytomegalovirus (CMV) disease often represents a serious complication that promotes opportunistic infections in heart transplant recipients. In this study we evaluated the impact of preemptive gancylovir therapy, guided by pp65 antigenemia on the morbidity associated with viral reactivation.

PATIENTS AND METHODS

We have performed a CMV infection surveillance program since March 1999, with antigenemia pp65 determinations weekly for the first 2 months biweekly in the third months, and monthly to the sixth month. Patients with pp65 antigenemia value >/= 10 positive cells per 2 x 10(5) polymorphonuclear cells (PMN) were treated with intravenous gancyclovir followed by 1 month of oral gancyclovir.

RESULTS

Among the 107 patients who underwent the virological monitoring, 80 were pp65 antigenemia-positive with preemptive therapy administered in 48 cases. Five patients displayed symptomatic CMV disease (4.7% vs 18% rate in the period of 1988 to 1998 before the introduction of virologic monitoring; P <.01). We observed only one case of gancyclovir-resistant pneumonia which was successfully treated with foscarnet. CMV recurrence in 10 patients required a second cycle of gancyclovir treatment. Our experience included 13 opportunistic infections (12.7%) with 11 antigenemia-positive.

CONCLUSIONS

Preemptive therapy drastically reduces the incidence of CMV disease and the associated morbidity. Compared to universal prophylaxis, this approach may avoid unnecessary pharmacologic treatment in more than 50% of transplant recipients. Indeed, preemptive therapy does not fully prevent CMV disease, because it may manifest at the first antigenemia determination, and furthermore may select gancyclovir-resistant strains.

Internal auditory canal metastasis

This report deals with 3 cases of internal auditory canal metastasis, an extremely rare lesion, few cases having been reported in the international literature. Since pre-operative diagnosis is fundamental in the planning of a correct therapeutic strategy, it is important that the neurotologist be aware of the possibility of their occurrence in this particular area. Metastasis can occur unilaterally as well as bilaterally; the latter being the case in 1 of the patients described herein. Correct pre-operative diagnosis is particularly difficult in patients in whom the primary tumour has not been detected at the time of identification of the lesion in the internal auditory canal. The only characteristic, specific of metastasis, is the presence of multifocal cerebral lesions. However, these were detected in only 1 of the present cases. On the contrary, in cases of a single metastasis, both magnetic resonance imaging and computed tomography usually fail to show any distinctive feature when compared to the most common tumours of the internal auditory canal (vestibular schwannomas and meningiomas). Bilateral metastases can also be misdiagnosed as neurofibromatosis type 2. Clinical data that should alert the clinician are: rapidly progressive sensorineural hearing loss, followed by onset of progressive facial nerve weakness. Radiotherapy and/or chemotherapy are the two main treatment modalities, while surgical removal is reserved for selected cases of a single metastasis. Albeit, due to the paucity of specific radiological and clinical characteristics, surgical removal is often necessary to reach the correct diagnosis, as occurred in 2 of the present patients.

Midterm results of a prospective randomized comparison of two different rabbit-antithymocyte globulin induction therapies after heart transplantation

This prospective randomized study compared the effects in heart transplant recipients of thymoglobulin and ATG, two rabbit polyclonal antithymocyte antibodies available for induction therapy. Among 40 patients (29 men and 11 women, mean age: 40.7 +/- 14 years) undergoing orthotopic heart transplantation, 20 were randomly allocated to receive induction with thymoglobulin (group A) and 20 to ATG-fresenius (group B). Comparisons between the two groups included early posttransplant (6 months) incidence of acute rejection episodes (grade >/= 1B), bouts of steroid-resistant rejection, time to first rejection, survival, graft atherosclerosis, infections, and malignancies. The study groups displayed similar preoperative and demographic variables. No significant difference was found with regard to actuarial survival (P =.98), freedom from rejection (P =.68), number of early rejections > 1B (P =.67), mean time to first early cardiac rejection (P =.13), number of steroid-resistant rejections (P =.69). Cytomegalovirus reactivations were more frequent among group A (65%) than group B (30%; P =.028). New infections due to cytomegalovirus occurred only in group A (four patients; 20%; P =.05). No cases of malignancies were observed at a mean follow-up of 32.8 +/- 8.9 months. Although thymoglobulin and ATG showed equivalent efficacy for rejection prevention, they have different immunological properties. In particular, thymoglobulin seems to be associated with a significantly higher incidence of cytomegalovirus disease/reactivation.

Evolving practice patterns in heart transplantation: a single-center experience over 15 years

This analysis is a retrospective characterization of evolving patterns in donor and recipient risk factors for early and late outcomes (survival and freedom from rejection) along with determinants of hospital and 1-year mortality after heart transplantation over a 15-year experience in a single center. Profiles and outcomes were evaluated for procedures performed between 1988 and 1995 (group A, n = 105) versus 1996 and 2003 (group B, n = 218). The following parameters were considered: pretransplant diagnosis, recipient age UNOS status, donor age, total postretrieval ischemic time, donor/recipient size match, and degree of myocardial necrosis at biopsy. Recipients in group B were significantly more compromised as demonstrated by UNOS status (11.4% vs 19.3%; P =.05) and pretransplant pulmonary vascular resistance (2.3 +/- 1.5 vs 3.1 +/- 1.5; P =.04). Marginal donors were more frequently used for group B procedures (21.9% vs 47.7%; P <.0001). Outcomes were significantly more favorable among group B patients in terms of hospital mortality (18.1% vs 10.6%; P =.046), and 1- and 5-year actuarial survival (72.4% vs 83.4%, 60% vs 73.3%, respectively; P =.006). Analysis of the causes of death disclosed a significant reduction in fatal events due to graft failure and acute rejection in group B. No difference emerged with regard to actual freedom from acute rejection. Determinants of hospital mortality were pretransplant diagnosis, UNOS status, donor age, and cardioplegic solution. Transplant era, recipient age, infectious episodes, and ischemic necrosis at biopsy were risk factors for 1-year mortality. We conclude that despite extensive usage of marginal donors and selection of worse candidates, significantly better outcomes were achieved due to improvements in global management strategies.

[Neuropsychological profiles in preterm low birth weight children]

AIM

Several studies focus on the psychic development of extremely low birth weight (ELBW) preterm infants and highlight the presence of neurological, cognitive and relating disorders. Several contributions have in fact shown that in these subjects in school age disturbances of cognitive functions may be encountered; in particular, disturbances of specific neuropsychological functions, such as attention defects, impaired visuo-spatial function, memory and language have been reported in subjects with a globally normal intelligence quotient.

METHODS

Forty-three school-aged children were studied (21 males and 22 females). They had a low birth weight (weight between 1,050-2,450 g), the gestation period was between 29 and 32 weeks and they were compared with a control sample whose birth weight was >2,500 g. Cognitive development was assessed by a test battery including WISC-R, Zazzo "deux Barrage" Test, Benton Visual Retention Test and Frostig Developmental Test of Visual Perception. Parents were also called in to evaluate how they had experienced the birth of their child and how long the mother had been kept in the clinic.

RESULTS

The overall analysis of our study suggests normal cognitive development in these children. No significant diffences were detected in the 2 studied groups. The lack of differences could be associated with the criteria used to select our sample because no children with severe perinatal disorders were included in the study. In addition, a good mother-child relationship seems to have been established in these children and this has certainly contributed to cognitive development adequate to their age.

CONCLUSION

The prognosis of these children is therefore closely related both to the birth weight and, especially, to the difficulties faced in the neonatal age (severe perinatal diseases).

Post-prandial triglyceride profile in a population-based sample of Type 2 diabetic patients

AIMS/HYPOTHESIS

Postprandial lipaemia is considered an emerging risk factor for cardiovascular disease also in the Type 2 diabetic population. However, little information exists on the daily triglyceride profile of these patients, especially during everyday life. The aim of the study was to evaluate the daily triglyceride profile of Type 2 diabetic patients during their everyday life.

METHODS

145 Type 2 diabetic patients (66 men/79 women, age range 45-65 years) at a health district near Naples, Italy, participating in a screening survey for the evaluation of diabetic complications, and 30 non-diabetic subjects of the same area underwent four daily capillary triglyceride profiles by Accutrend (Roche)-a previously validated method.

RESULTS

Triglyceride values (mmol/l; Means +/- SE) were 2.22+/-0.08 at fasting, decreased before lunch (2.03+/-0.07), reached a peak 3 h after lunch (2.73+/-0.09) and remained substantially high before dinner (2.47+/-0.09) (all p<0.001 vs fasting). The triglyceride profile of non-diabetic subjects was significantly lower at each point (average difference of 0.73 mmol/l). The percentage of patients with values above 2.25 mmol/l was 61% 3 h after lunch and 49% before dinner. Moreover, in 30% of patients with optimal fasting values (<1.69 mmol/l) triglyceride concentrations 3 h after lunch ranged between 1.69 and 2.25 mmol/l, and in 31% they were above 2.25 mmol/l.

CONCLUSION/INTERPRETATION

Most Type 2 diabetic patients have postprandial triglycerides above optimal concentrations for several hours after meals. Moreover, optimal fasting concentrations are not always a good predictor of postprandial triglycerides.

Systems for regulated or tissue-specific gene expression

The achievement of efficient regulation and/or tissue-specific gene expression is one of the major goals for gene therapists. A number of inducible systems and tissue-specific promoters are currently available. Studies in vitro and in vivo have shown promising results in controlling gene expression. However, the achievement of efficient gene regulation in patients is still an open question. This review describes the main inducible systems and tissue-specific promoters in view of their potential therapeutic applications.

Stem cell transplantation therapy: Controversy over ethical issues and clinical relevance

The possibility of regenerating tissues would provide an effective therapeutic tool for the treatment of many pathological conditions, including neurological diseases, spinal cord injuries, cardiopathies, diabetes, hematological illnesses and genetic disorders. While stem cells may have the potential of regenerating a variety of tissues, as indicated by a number of groundbreaking but preliminary reports, ethical issues and safety considerations seem to preclude the use of human embryonic stem cells in the clinical setting. Adult stem cells might circumvent the issues posed by embryonic stem cells, although the potential plasticity of adult stem cells is under scrutiny because of many conflicting and contradictory reports in the field of stem cell research. Indeed, many aspects of the biology of stem cells are still not known. In this respect, stem cell biologists have to address several pressing issues. A better understanding of stem cell biology would almost certainly allow for the establishment of efficient and reliable cell transplantation experimental programs in the clinic.

[The treatment of fecal incontinence]

The treatment of faecal incontinence includes: the education of the patient, medical therapy, biofeedback and sphincteric exercises, surgical therapy. Conservative, non-surgical treatment is almost always the initial therapeutic approach, except in those cases in which an evident defect of the sphincter muscle is present. Surgical treatment has seen a noteworthy increase in the last fifteen years as a consequence of the development of new surgical techniques. These techniques include: external anal sphincter plasty, pelvic floor plasties, sacral neuromodulation, muscular transpositions with or without electrostimulation, artificial anal sphincter. These procedures may be employed as first or second level treatment depending on the type of pathology considered and its aetiology. The 1st results achieved by surgical treatment authorise us to believe that reconversion with artificial sphincter is a valid alternative to graciloplasty, notwithstanding the fact that its costs are higher. Attentive pre- operative assessment of patients is important. Patients must be strongly motivated and able to manage the new condition. Although further studies are necessary, the degree of satisfactory of the 1st patients operated is the best stimulus for pursuing the development of this technique.

Human immunodeficiency virus type 1 (HIV-1) derived vectors: safety considerations and controversy over therapeutic applications

The latest generation of lentiviral vectors based on HIV-1 is one of the most efficient tools for gene transduction of mammalian cells. However, the possible employment of HIV-based vectors in clinical trials is a very controversial issue, mainly due to safety and ethical concerns. HIV-1 is a lethal pathogenic agent, which induces AIDS. Genetic vectors must derive either from viruses that are not pathogenic in humans, or that eventually just cause mild illnesses. Patients exposed to HIV-based vectors will test seropositive to certain components of HIV-1. In addition, there might be other possible adverse effects in patients that cannot be predicted, as many aspects of the pathogenesis of AIDS have not been completely understood yet. On these grounds, it seems necessary to improve the design of other lentiviral vectors, which derive from viruses that are not pathogenic in humans and are distantly related to primate retroviridae.

Long-term follow-up after endoscopic biliary stent placement for bile duct strictures from laparoscopic cholecystectomy

BACKGROUND/AIMS

The outcome of endoscopic biliary stent insertion for postoperative bile duct stenosis was retrospectively evaluated.

METHODOLOGY

Fifty-seven patients with biliary stenosis from laparoscopic cholecystectomy were included from February 1992 to January 2000. One to three stents were inserted for an average of 12.4 months, with stent exchange every 3 months to avoid cholangitis caused by clogging.

RESULTS

Successful stent insertion was achieved in 43/57 (75.4%) patients. Stent insertion failed in 10 patients with complete and in 4 patients with incomplete biliary obstruction. Early complications occurred in 4 patients. Late complications occurred in 5/43 patients. Five patients experienced recurrence of stenosis.

CONCLUSIONS

Endoscopic treatment should be the initial management of choice for postoperative bile duct stenosis.

Gene transfer in experimental medicine

Gene transfer technology has many potential applications in medicine. Phase I and phase II gene-based clinical trials have been conducted for the treatment of cancer, monogenic disorders, some neurodegenerative illnesses, cardiopathies and infectious diseases. A phase I gene therapy clinical trial has recently been approved for the treatment of Parkinson's disease, while preclinical studies are in progress to develop gene-based interventions for the treatment of Alzheimer's disease and Huntington's disease, amyotrophic lateral sclerosis, spinal cord injury, and diabetes type 1 and type 2. A number of gene transfer models have been generated for gene therapy and genetic immunization programs. Vector design is addressing several pressing issues in the matter of gene delivery improvement, stabilization of transgene expression and safety. This is necessary in order to achieve efficient gene-based therapeutic interventions. Indeed, considerable progress has been reported in the field of vector design, which has produced some encouraging results in clinical trials and preclinical studies. However, vector design should be further developed to allow for the successful application of gene transfer technology in therapy. This review summarizes the latest achievements and controversies in clinical trials and preclinical studies in the field of gene therapy.

Factors influencing hospital infection control policies in Italian hospitals

A study was undertaken to determine the resources available in Italian hospitals for the control of nosocomial infections and the factors favouring a successful approach. During January-May 2000 a questionnaire about infection control was sent to the hospital health director of all Italian National Health System hospitals treating acute patients and with more than 3500 admissions in 1999. An active programme was defined as a hospital infection control committee (HICC) meeting at least four times in 1999, the presence of a doctor with infection control responsibilities, a nurse employed in infection control and at least one surveillance activity and one infection control guideline issued or updated in the past two years. There was a response rate of 87.5% (463/529). Almost fifteen percent (69/463) of hospitals had an active programme for Infection Control and 76.2% (353/463) had a HICC. Seventy-one percent (330/463) of the hospitals had a hospital infection control physician and 53% (250/463) had infection control nurses. Fifty-two percent (242/463) reported at least one surveillance activity and 70.8% (328/463) had issued or updated at least one guidance document in the last two years. The presence of regional policies [odds ratio (OR) 8.7], operative groups (OR 4.2), at least one full-time nurse (OR 4.6) and a hospital annual plan which specified infection control (OR 2.1) were statistically associated with an active programme in the multivariate analysis.

Treatment strategies for postinfarction left ventricular free wall rupture: stabilization with peri-operative IABP and off-pump repair

BACKGROUND

Perioperative management of post-infarction left ventricular free wall rupture (LVFWR) is not clearly standardized and surgical repair is the only therapeutic option. Role of off-pump surgery and stabilization with perioperative intraaortic balloon pumping (IABP) were here analysed.

METHODS

Seven patients underwent surgery for LVFWR between 1990 and 2002. Clinical picture included electromechanical dissociation (3 patients) and sudden hypotension (4 patients). Except in one patient who was reanimated through femoro-femoral cardiopulmonary bypass, off-pump repair through on-lay patching technique was always performed. IABP was employed in the immediate postoperative period in five cases.

RESULTS

A satisfactory hemodynamic state was restored in all cases and there were no reoperations for bleeding or rerupture. Hospital survival was 100%. One patient underwent successful surgical myocardial revascularization two months after LVFWR. Two patients died at follow-up. The survivors present with good NYHA and CCS functional classes.

CONCLUSIONS

When the anatomy of the LVFWR is favourable, off-pump external patching repair proves a good choice. Postoperative IABP provides satisfactory hemodynamic support.

Should we continue to study high-dose chemotherapy in metastatic breast cancer patients? A critical review of the published data

Data from eight randomised trials on high-dose chemotherapy (HDC) for metastatic breast cancer (MBC) have been published, but only seven studies are evaluable after the Bezwoda trial was discredited. Moreover, overall survival (OS) has been evaluated in only four out of seven studies since three had a crossover design. OS was similar for the HDC and standard-dose chemotherapy (SDC) group in the four evaluable trials, while disease-free survival (DFS) was improved in the HDC group in six of the seven trials. The delay in relapse for patients with metastatic disease represents an important clinical outcome; furthermore, since none of the reported studies randomised more than 220 patients, their statistical power may have been too limited to detect meaningful survival differences. Finally, preliminary experiences have shown that HDC seems to be the ideal platform upon which to build novel therapies. In conclusion, HDC remains an important field of clinical research for breast cancer patients with stage IV disease and, from the studies reported in this article, there is some evidence for offering this therapeutic modality to selected patients who are interested in a medically aggressive approach.