Search PubMed⌕ Search

Biomedical subjects

R Iorio

Publications and source records attributed to R Iorio.

At least 19 recordsLinked to original sources
PubMed2002

Possible role for Ca(2+) calmodulin-dependent protein kinase II as an effector of the fertilization Ca(2+) signal in mouse oocyte activation.

The present study shows that Ca(2+) calmodulin-dependent protein kinase II (CaM kinase II) is physiologically activated in fertilized mouse oocytes and is involved in the Ca(2+) response pathways that link the fertilization Ca(2+) signal to meiosis resumption and cortical granule (CG) exocytosis. After 10 min of insemination, CaM kinase II activity increased transiently, then peaked at 1 h and remained elevated 30 min later when most of the oocytes had completed the emission of the second polar body. In contrast, in ethanol-activated oocytes the early transient activation of CaM kinase II in response to a monotonic Ca(2+) rise was not followed by any subsequent increase. Inhibition of CaM kinase II by 20 micromol/l myristoylated-AIP (autocamtide-2-related inhibitory peptide) negatively affected MPF (maturing promoting factor) inactivation, cell cycle resumption and CG exocytosis in both fertilized and ethanol-activated oocytes. These results indicate that the activation of CaM kinase II in mouse oocytes is differently modulated by a monotonic or repetitive Ca(2+) rise and that it is essential for triggering regular oocyte activation.

Animals↗
PubMed2001

Primary Charnley total hip arthroplasty: a comparison of American and Japanese cohorts followed for 10-20 years.

Primary Charnley total hip arthroplasties (THAs) followed for 10 to 20 years were compared between an American (183 sockets and 178 femoral prostheses) and a Japanese (145 sockets and 148 femoral prostheses) series, each performed by a single surgeon at a single hospital using similar techniques. The primary etiology was developmental dysplasia of the hip (70%) in the Japanese series and primary osteoarthrosis (50%) in the American series. Radiographic socket survival was inferior in the Japanese series at 4- to 11-year follow-up, which was attributed mainly to the etiologic difference. The American patients had higher levels of postoperative activity and developed more accelerated polyethylene wear, which may lead to an increased loosening rate of sockets > or = 10 years after THA. The American series had higher rates of femoral revision at > or = 9 years follow-up, which was attributed mainly to lower canal flare indices in that series.

Arthroplasty, Replacement, Hip↗
PubMed2001

Venous thromboembolic disease management patterns in total hip arthroplasty and total knee arthroplasty patients: a survey of the AAHKS membership.

The American Association of Hip and Knee Surgeons (AAHKS) distributed a survey to its members exploring practice patterns implemented to prevent venous thromboembolic disease (VTED) in patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). Of 720 (33%) members, 236 responded. Prophylaxis was prescribed for 100% of patients during the course of hospitalization for THA and TKA. Warfarin was the commonest pharmacologic treatment used for THA (66%) and TKA (59%) patients. Low-molecular-weight heparin was used in 16% of THA patients and 18% of TKA patients. The most commonly employed mechanical modality was pneumatic devices in THA (51%) and TKA (50%). Universal acceptance of the need for prophylaxis administration for patients undergoing THA and TKA is shown. The method and duration remain highly variable; although the survey illustrates such variation, it suggests there is no one best method of prophylaxis.

Anticoagulants↗
PubMed2001

Displaced femoral neck fractures in the elderly: outcomes and cost effectiveness.

The optimal treatment for displaced femoral neck fractures in elderly patients is a matter of controversy. Four surgical options are well supported in the orthopaedic literature: reduction with internal fixation, unipolar hemiarthroplasty, bipolar hemiarthroplasty, and total hip arthroplasty. Based on a review of the outcomes literature regarding treatment of femoral neck fractures and a cost-effectiveness analysis, an algorithm for surgical treatment of displaced femoral neck fractures in elderly patients is presented. Cost-effectiveness analysis of these four surgical treatment options shows that arthroplasty is the most cost-effective treatment when complication rate, mortality, reoperation rate, and function are evaluated during a 2-year postoperative period. These data were strongly supported by a two-way sensitivity analysis that varied the effectiveness of the interventions and the costs. Literature derived outcome studies show that elderly patients with displaced femoral neck fractures achieve the best functional results with a well healed femoral neck without osteonecrosis after reduction and internal fixation. Achieving this result may be difficult, and it is not as cost effective as arthroplasty.

Arthroplasty, Replacement, Hip↗
PubMed2001

An epidemiological survey of hepatitis C virus infection in Italian children in the decade 1990-1999.

BACKGROUND: A retrospective-prospective survey of Italian children with hepatitis C virus (HCV) infection was planned in 1998 to explore the epidemiologic features of infection during the past decade. METHODS: Anti-HCV-positive patients (or HCV RNA-positive infants) aged 1 month to 16 years, consecutively observed in 20 pediatric Institutions, were considered. An anonymous epidemiologic questionnaire based on clinical records was used. RESULTS: From 1990 through March 1999, 606 patients were observed (296 boys, average age 5.8 years). Maternal infection (46% of cases) and blood transfusions (34%) were the most frequent risk factors. Of 279 infected mothers, 61% did not recall a putative source of infection (by history, many could possibly have had exposure through routes such as therapeutic injections with nondisposable material), whereas 94 (34%) admitted drug abuse, including 49 (17%) coinfected with human immunodeficiency virus (HIV). Only 157 (26%) children were born after 1991: 90% of their mothers were infected (11% were HIV coinfected vs. 25% mothers of older children, P < 0.01). CONCLUSIONS: Maternal infection is a prominent source of pediatric HCV infection in Italy. The fact that most mothers had a history of covert exposure to HCV, probably through percutaneous routes that are no longer operating, and that the number of those with HIV coinfection has decreased suggests that the frequency of pediatric infection could decrease in the future.

Adolescent↗
PubMed2000

Predictive value of Epstein-Barr virus genome copy number and BZLF1 expression in blood lymphocytes of transplant recipients at risk for lymphoproliferative disease.

Epstein-Barr virus (EBV) genome numbers and RNA transcripts from the immediate-early EBV gene BZLF1 were monitored by means of polymerase chain reaction in peripheral blood lymphocytes (PBLs) of 44 children who received liver transplants. The 2 tests were compared, using several parameters to assess their value as predictors of posttransplantation lymphoproliferative disease (PTLD). All patients were infected with EBV. BZLF1 mRNA was positive in 70% of patients, with highest expression in those with largest virus load. Four patients developed PTLD that could not be unequivocally diagnosed by any of the parameters considered alone. Sensitivity of EBV genome number (>/=40,000 EBV copies/10(5) PBLs) and BZLF1 mRNA (BZLF1:glyceraldehyde-3-phosphate-dehydrogenase ratio >/=0.5) was 100%. Specificity of each of the 2 tests alone (98% and 58%, respectively) improved (to 100% and 83%, respectively) when measurement of serum IgG level was included. Because decreased virus load, but not BZLF1 mRNA expression, accurately predicted favorable responses of PTLD to therapy, monitoring of EBV genome numbers alone appears sufficient in children with liver transplants.

Adolescent↗
PubMed2000

Poor bone quality or hip structure as risk factors affecting survival of total-hip arthroplasty.

BACKGROUND: The principal long-term complication after total hip arthroplasty (THA) has been aseptic fixation failure. Many hip prostheses and operative techniques have been developed to improve outcomes, but few measures have been taken to cope with poor bone quality or hip structure. We assessed risk factors for aseptic fixation failure after THA. METHODS: We assessed, by multivariate analysis, survival of 405 primary Charnley THAs to identify risk factors for aseptic fixation failures. We also investigated risk factors for development of rapid polyethylene wear (penetration depth of the femoral head into the socket polyethylene > or = 2 mm/year) FINDINGS: In the entire series of 405 THAs, with use of radiographic fixation failure or revision for a loose socket as the endpoint, development of rapid polyethylene wear and the preoperative diagnosis of atrophic osteoarthrosis (defined by scarce osteophyte formation) were identified as risk factors for socket loosening (p < or = 0.02). A medullary canal with an unfavourable geometry (a stovepipe canal, Noble's canal-flare index < 3.0) was the only risk factor for femoral fixation failure (p < or = 6.7x10(3)). The only variable related to development of rapid polyethylene wear was the type of steel used in the femoral prosthesis--Ortron 90 prostheses significantly lowered the rate of development of rapid wear from 12.7% to 0.4%. In the 248 THAs in which these femoral prostheses were used, socket survival was affected only by the preoperative diagnosis of atrophic osteoarthrosis (for radiographic fixation failure and revision, p=4.0x10(-5) and p=0.042, respectively). INTERPRETATION: In THA, the critical risk factors are poor bone quality, which manifests as atrophic osteoarthrosis, for socket survival and poor bone structure for femoral-prosthesis survival. To ensure longer durability of THAs, these factors should be assessed further and efforts, especially biological initiatives, should be made to resolve them.

Arthroplasty, Replacement, Hip↗
PubMed2000

The association of excessive warfarin anticoagulation and postoperative ileus after total joint replacement surgery.

Patients undergoing joint replacement who show signs of ileus in the postoperative period that require insertion of a nasogastric tube (NGT) must be monitored closely to avoid bleeding complications. The diagnosis of postoperative ileus was documented in 40 of 2,526 (1.6%) consecutive joint replacement operations between January 1, 1990, and March 1, 1998, at 1 hospital. Of the 40 patients with postoperative ileus, 34 received warfarin postoperatively. Of these 34 patients, 19 required a NGT for >48 hours, and 15 patients required a NGT for <48 hours or did not require a NGT. Of the 19 patients who required a NGT for >48 hours and who received warfarin anticoagulation, 17 had a prothrombin time of >20 seconds or an international normalized ratio (INR) of >2.0. None of the 15 patients who required a NGT for <48 hours and who received warfarin anticoagulation had a prothrombin time of >20 seconds or an INR of >2.0. This difference was highly statistically significant (P < .001).

Anticoagulants↗
PubMed2000

Athletic activity after total knee arthroplasty.

Americans are aging, elderly Americans are more active, and the prevalence of total knee arthroplasty is increasing. Indications for knee replacement include pain, deformity, and a desire to improve function. When patients have knee replacement operations, frequently they increase their activities. It is important for patients with knee replacements to understand the impact of athletic activity on the outcome of knee replacements. Orthopaedic surgeons should educate patients regarding athletic activity after total knee arthroplasty. Considerations and risk factors for athletic activity after knee replacements include athletic activity before surgery, preoperative rehabilitation, surgical reconstruction, implant failure or fracture, implant fixation or loosening, and joint bearing surface wear. Anatomic reconstruction and compulsive postoperative rehabilitation with restoration of muscular control are important for optimum function after total knee arthroplasty. In general, patients with knee replacements are encouraged to participate in low-impact, low-demand sports, and to avoid high-impact, high-demand sports.

Arthroplasty, Replacement, Knee↗
PubMed2000

The role of bladder catheterization in total knee arthroplasty.

The use of a urinary bladder catheter in the perioperative period for patients undergoing total knee arthroplasty is controversial. In the current study, two bladder management protocols were studied. One group of patients had an indwelling catheter inserted into the bladder before total knee arthroplasty. The other group of patients was observed and treated for urinary retention as necessary. From 1993 to 1998, 652 patients undergoing primary, unilateral total knee arthroplasty were randomized by surgeon into two groups: one group underwent preoperative insertion of an indwelling bladder catheter (306 patients), and one group (346 patients) had a catheter inserted postoperatively as necessary. Sixty-six percent (229 of 346) of these patients required catheterization (203 had indwelling catheters and 26 had intermittent straight catheters). A urinary tract infection developed in five patients (1.6%) in whom a catheter was inserted preoperatively. A urinary tract infection developed in six patients (1.7%) in whom a catheter was inserted if necessary. Five of these urinary tract infections developed in patients with delayed indwelling bladder catheters. A urinary tract infection did not develop in any patient in whom a straight catheter was inserted. There was no significant difference in the length of stay in the hospital between the two groups. The group in whom a catheter always was inserted generated $491 greater cost for total knee arthroplasty than patients in whom a catheter was inserted if necessary.

Adult↗
PubMed2000

Long term effect of alpha interferon in children with chronic hepatitis B.

BACKGROUND/AIMS: The purpose of this study was to better define the long term prognosis of infection and disease in children with chronic hepatitis B treated with interferon (IFN) alpha. PATIENTS: A total of 107 children with chronic hepatitis B who received IFN alpha for three or six months in two clinical trials were followed for a mean period of 69 (17) months. Response to treatment was defined as loss of hepatitis B e antigen (HBeAg) within 12 months after stopping treatment. A control group of 59 patients was also followed for a shorter mean time (46 (19) months). RESULTS: Sixteen (15%) treated children responded during therapy and 18 (17%) during post-treatment follow up; 31 (29%) non-responders lost HBeAg during subsequent years. High pretreatment levels of transaminases and a greater histological activity index were predictors of response. Kaplan-Meier estimates of cumulative HBeAg clearance rates at five years were similar between treated patients (60%) and controls (65%). After HBeAg clearance, all cases lost hepatitis B virus DNA and 94% had normal transaminase levels. Loss of hepatitis B surface antigen (HBsAg) occurred in four (25%) patients who responded during treatment but in none of the other treated or untreated patients. CONCLUSIONS: After five years' observation, the proportion of treated children with sustained HBeAg clearance comprised an equal number of responders and non-responders and did not differ from that observed in untreated controls, suggesting that IFN simply accelerated a spontaneous event. However, IFN significantly improved the rate of HBsAg loss in cases with more prominent disease activity who were early responders, and may be particularly useful in this type of patient.

Adolescent↗
PubMed2000

Single Price/Case Price Purchasing in orthopaedic surgery: experience at the Lahey Clinic.

BACKGROUND: Hospital revenues for orthopaedic operations are not keeping pace with inflation or with rising hospital expenses. In an attempt to reduce the hospital cost of orthopaedic operations by reducing the cost of operating-room supplies, we developed a Single Price/Case Price Purchasing Program for implants used in total hip arthroplasty, total knee arthroplasty, and total shoulder arthroplasty as well as for arthroscopic shavers and burrs, interference screws, and bone-suture anchors. METHODS: The Lahey Clinic asked orthopaedic vendors to supply all instruments, implants, and disposable items related to these selected products for one single price per unit or case. For example, a single price for total hip arthroplasty implants included instruments, acetabular cups, acetabular liners, acetabular screws, femoral stems, femoral heads, and stem centralizers, if required. The hospital implemented the Single Price/ Case Price Purchasing Program with a competitive-bid request for proposal. Surgeons evaluated the responses to the bidding process, and they made final decisions on product selection. RESULTS: The Single Price/Case Price Purchasing Program at the Lahey Clinic was successful in reducing the cost of orthopaedic implants and supplies. In the present article, we could not disclose the specific prices that we agreed to pay our vendors. The specific cost reductions were 32 percent for hip implants with a change of vendor, 23 percent for knee implants without a change of vendor, 25 percent for shoulder implants with a change of vendor, 45 percent for arthroscopic shavers and burrs without a change of vendor, 45 percent for interference screws without a change of vendor, and 23 percent for bone-suture anchors without a change of vendor. CONCLUSIONS: The Single Price/Case Price Purchasing Program at the Lahey Clinic allowed the hospital to reduce its cost of orthopaedic operations by lowering the cost of operating-room supplies. This cost reduction is important in a health-care economy in which hospital revenues per unit of service or care are decreasing.

Arthroplasty, Replacement↗
PubMed1999

Jagged-1 mutation analysis in Italian Alagille syndrome patients.

Alagille syndrome (AGS) is an autosomal dominant disorder with developmental abnormalities affecting the liver, heart, eyes, vertebrae, and craniofacial region. The Jagged-1 (JAG1) gene, which encodes a ligand of Notch, has recently been found mutated in AGS. In this study, mutation analysis of the JAG1 gene performed on 20 Italian AGS patients led to the identification of 15 different JAG1 mutations, including a large deletion of the 20p12 region, six frameshift, three nonsense, three splice-site, and two missense mutations. The two novel missense mutations were clustered in the 5' region, while the remaining mutations were scattered throughout the gene. The spectrum of mutations in Italian patients was similar to that previously reported. We also studied in detail a complex splice site mutation, 3332dupl8bp, which was shown to lead to an abnormal JAG1 mRNA, resulting in a premature stop codon. With the exception of the missense mutations, the majority of the JAG1 mutations are therefore likely to produce truncated proteins. Since the phenotype of the patient with a complete deletion of the JAG1 gene is indistinguishable from that of patients with intragenic mutations, our study further supports the hypothesis that haploinsufficiency is the most common mechanism involved in AGS pathogenesis. Furthermore, our data confirmed the absence of a correlation between the genotype of the JAG1 gene and the AGS phenotype.

Alagille Syndrome↗