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M Grasso

Publications and source records attributed to M Grasso.

At least 73 records · Page 4Linked to original sources
PubMed1999

Divergence between stone composition and urine supersaturation: clinical and laboratory implications.

PURPOSE: In general high urine supersaturation with respect to calcium oxalate, calcium phosphate or uric acid is associated with that phase in stones. We explore the exceptions when supersaturation is high and a corresponding solid phase is absent (type 1), and when the solid phase is present but supersaturation is absent or low (type 2). MATERIALS AND METHODS: Urine supersaturation values for calcium oxalate, calcium phosphate and uric acid, and other accepted stone risk factors were measured in 538 patients at a research clinic and 178 at stone prevention sites in a network served by a single laboratory. RESULTS: Of the patients 14% lacked high supersaturation for the main stone constituent (type 2 structural divergence) because of high urine volume and low calcium excretion, perhaps from changes in diet and fluid intake prompted by stones. Higher calcium excretion and low urine volume caused type 1 divergences, which posed no clinical concern. CONCLUSIONS: Type 1 divergence appears to represent a condition of low urine volume which raises supersaturation in general. Almost all of these patients are calcium oxalate stone formers with the expected high supersaturation with calcium oxalate as well as high uric acid and calcium phosphate supersaturations without either phase in stones. Type 2 divergence appears to represent an increase in urine volume and decrease in urine calcium excretion between stone formation and urine testing.

Calcium Oxalate↗
PubMed1999

Vaccine storage in the community: a study in central Italy.

Maintaining the vaccine cold chain is an essential part of a successful immunization programme, but in developed countries faulty procedures may occur more commonly than is generally believed. A survey was conducted in a health district in central Italy to assess the methods of vaccine transportation and storage. Of 52 primary vaccination offices inspected, 39 (76.5%) had a refrigerator for vaccine storage but only 17 (33.3%) kept records of received and stored doses. None of the seven main offices selected for monitoring had a maximum and minimum thermometer and none monitored the internal temperature of the refrigerator. Moreover, other faulty procedures, such as the storage of food and laboratory specimens in vaccine refrigerators and the storage of vaccines on refrigerator door shelves, indicated that the knowledge and practice of vaccine storage and handling were often inadequate.

Documentation↗
PubMed1999

Examining the obstructed ureter with intraluminal sonography.

PURPOSE: Intraluminal sonography was used to define, differentiate and direct better treatment of obstructing ureteral lesions. MATERIALS AND METHODS: A total of 63 patients with a history of ureteral obstruction and suspected stricture were accrued for evaluation. All patients underwent retrograde contrast imaging, ureteroscopy and intraluminal sonography as part of a diagnostic algorithm. Specific sonographic criteria to differentiate lesions and stricture types were developed. Associated complicating variables defined on sonography included foreign bodies, submucosal stone fragments, ureteral wall fibrosis, mass lesions and adjacent vasculature. Endoscopic treatment was then performed with ultrasound guidance if technically feasible. RESULTS: A total of 63 ureters were evaluated with the preoperative diagnosis of ureteral stricture disease. All ureters were narrowed on contrast imaging in the segment where a stricture was suspected. On sonography 24 ureters (36%) had wall fibrosis with normal periureteral tissues. In general these strictures did well with endoscopic incision. Of the 67 ureters 13 (19%) were thickened or had edematous walls with normal architecture and without fibrosis. These patients all did well with expectant therapy. In contrast, 7 ureters (10%) were obstructed by segmental retroperitoneal fibrosis which did not respond to minimally invasive therapies. In addition, 8 ureters (12%) were obstructed by ureteral wall scarring and periureteral fibrosis, and required open surgical intervention. Ten ureteral strictures had adjacent vasculature, and endoscopic incisions under ultrasound guidance were directed safely away from these structures without associated morbidity. Calculi, stone fragments and foreign bodies embedded in the ureteral wall with associated inflammation were defined with sonography and responded to endoscopic therapies. The intraluminal sonographic diagnosis of ureteral endometriosis was made in 6 patients with a range of lesions from bright, hyperechoic blood filled cysts to an inhomogeneous fluid filled scar involving the wall and periureteral tissues. Primary ureteral carcinoma was also demonstrated in 2 patients after other diagnostic techniques failed. In 1 of these patients intraluminal sonography directed biopsies diagnosed submucosal tumor. Finally, 1 patient had a small periureteral urinoma on intraluminal sonography which was missed on other imaging studies. CONCLUSIONS: Intraluminal sonography is useful in patients with ureteral obstruction of unclear etiology as well as for selecting patients who may benefit from minimally invasive therapies and safely directing these treatments.

Adolescent↗
PubMed1999

Conservative surgery in small renal tumors: our experience.

OBJECTIVE: We evaluated the effectiveness and safety of the nephron-sparing surgery in the treatment of low stage, easily accessible renal cell carcinoma versus radical nephrectomy, the "gold standard" therapy according to data in the literature. METHODS: From 1988 to 1996, 36 patients (11 women and 25 men; mean age 59.6 years) with a small (< or = 5 cm) solitary renal cell carcinoma and a normal contralateral kidney were submitted to tumor enucleation through a transperitoneal approach. Hot ischemia was performed in 14 cases for an average of 16 minutes. In order to control the extent of surgical resection, in all cases frozen step sections of surgical margins were submitted to histopathological examination. The mean follow-up was 40 months. RESULTS: Complete local resection of the renal cell carcinoma was performed in all patients, with preservation to the furthest extent of the parenchyma not affected by the disease. Renal function remained normal in all cases. Bleeding was easily controlled without clamping the renal artery in 22 cases, while hot renal ischemia was necessary in the remaining 14 cases (mean ischemia time 16 minutes). Average blood loss was 450 cc. Frozen sections of the surgical margins were negative in all cases. Only one case of local recurrence was observed one year after the nephron-sparing operation, which was treated by radical nephrectomy. All patients are alive and cancer-free today. CONCLUSIONS: Elective tumor enucleation for low stage and easily accessible renal cell carcinoma can be performed safely and with a low risk of local recurrence. Definition of the appropriate pre-operative diagnostic approach, maximum tumor size, surgical mini-invasive approach and a longer follow-up are required before this procedure can be widely recommended.

Adult↗
PubMed1998

Restrictive cardiomyopathy, atrioventricular block and mild to subclinical myopathy in patients with desmin-immunoreactive material deposits.

OBJECTIVES: We present clinical data and heart and skeletal muscle biopsy findings from a series of patients with ultrastructural accumulations of granulofilamentous material identified as desmin. BACKGROUND: Desmin cardiomyopathy is a poorly understood disease characterized by abnormal desmin deposits in cardiac and skeletal muscle. METHODS: Clinical evaluation, endomyocardial and skeletal muscle biopsy, light and electron microscopy and immunohistochemistry were used to establish the presence of desmin cardiomyopathy. RESULTS: Six hundred thirty-one patients with primary cardiomyopathy underwent endomyocardial biopsy (EMB). Ultrastructural accumulations of granulofilamentous material were found in 5 of 12 biopsy samples from patients with idiopathic restrictive cardiomyopathy and demonstrated specific immunoreactivity with anti-desmin antibodies by immunoelectron microscopy. Immunohistochemical findings on light microscopy were nonspecific because of a diffuse intracellular distribution of desmin. All five patients had atrioventricular (AV) block and mild or subclinical myopathy. Granulofilamentous material was present in skeletal muscle biopsy samples in all five patients, and unlike the heart biopsy samples, light microscopic immunohistochemical analysis demonstrated characteristic subsarcolemmal desmin deposits. Two patients were first-degree relatives (mother and son); another son with first-degree AV block but without myopathy or cardiomyopathy demonstrated similar light and ultrastructural findings in skeletal muscle. Electrophoretic studies demonstrated two isoforms of desmin--one of normal and another of lower molecular weight--in cardiac and skeletal muscle of the familial cases. CONCLUSIONS: Desmin cardiomyopathy must be considered in the differential diagnosis of restrictive cardiomyopathy, especially in patients with AV block and myopathy. Diagnosis depends on ultrastructural examination of EMB samples or light microscopic immunohistochemical studies of skeletal muscle biopsy samples. Familial desminopathy may manifest as subclinical disease and may be associated with abnormal isoforms of desmin.

Adolescent↗
PubMed1998

Hepatitis C virus genotypes and clinical features in hepatitis C virus-related mixed cryoglobulinemia.

Mixed cryoglobulinemia is a systemic disease, almost always associated with hepatitis C virus infection and characterized by purpura and cutaneous vasculitis, asthenia, arthralgias, and often renal and neurological involvement. No significant differences have been described to date in mixed cryoglobulinemia patients with type 1, 2, or 3 hepatitis C virus infection with respect to symptoms, while a higher prevalence of genotype 2a has been reported in patients without clinical and biochemical signs of liver disease or with serum autoantibodies. We examined 33 hepatitis C virus-positive patients with mixed cryoglobulinemia to assess if any clinical or serological feature is related to infection with different genotypes. All subjects underwent viral genotype determination by means of a single-step polymerase chain reaction. Thirteen patients (39%) were infected with hepatitis C virus type 1b, 17 (52%) with type 2a or 2a/c, and 3 (9%) with type 3. There was a significant difference in the frequency of peripheral nervous system involvement: paresthesias or other symptoms of peripheral neuropathy were less frequent in patients with 2a or 2a/c infection (29%) than in patients with type 1b or type 3 infection (88%, P = 0.003). Only patients with hepatitis C virus type 2 had urticaria or cutaneous ulcers. These patients also had a lower frequency of arthralgias, lower cryocrit values (P = 0.02), and lower serum levels of alanine-aminotransferase and gamma-glutamyl-transpeptidase (P < 0.04) than patients with type 1 and type 3 infection. The prevalence of antinuclear antibody positivity was similar in the three groups.

Adult↗
PubMed1998

Mitochondrial DNA mutations and mitochondrial abnormalities in dilated cardiomyopathy.

Mitochondrial (mt)DNA defects, both deletions and tRNA point mutations, have been associated with cardiomyopathies. The aim of the study was to determine the prevalence of pathological mtDNA mutations and to assess associated defects of mitochondrial enzyme activity in dilated cardiomyopathy (DCM) patients with ultrastructural abnormalities of cardiac mitochondria. In a large cohort of 601 DCM patients we performed conventional light and electron microscopy on endomyocardial biopsy samples. Cases with giant organelles, angulated, tubular, and concentric cristae, and crystalloid or osmiophilic inclusion bodies were selected for mtDNA analysis. Mutation screening techniques, automated DNA sequencing, restriction enzyme digestion, and densitometric assays were performed to identify mtDNA mutations, assess heteroplasmy, and quantify the amount of mutant in myocardial and blood DNA. Of 601 patients (16 to 63 years; mean, 43.5 +/- 12.7 years), 85 had ultrastructural evidence of giant organelles, with abnormal cristae and inclusion bodies; 19 of 85 (22.35%) had heteroplasmic mtDNA mutations (9 tRNA, 5 rRNA, and 4 missense, one in two patients) that were not found in 111 normal controls and in 32 DCM patients without the above ultrastructural mitochondrial abnormalities. In all cases, the amount of mutant was higher in heart than in blood. In hearts of patients that later underwent transplantation, cytochrome c oxidase (Cox) activity was significantly lower in cases with mutations than in those without or controls (P = 0.0008). NADH dehydrogenase activity was only slightly reduced in cases with mutations (P = 0.0388), whereas succinic dehydrogenase activity did not significantly differ between DCM patients with mtDNA mutations and those without or controls. The present study represents the first attempt to detect a morphological, easily identifiable marker to guide mtDNA mutation screening. Pathological mtDNA mutations are associated with ultrastructurally abnormal mitochondria, and reduced Cox activity in a small subgroup of non-otherwise-defined, idiopathic DCMs, in which mtDNA defects may constitute the basis for, or contribute to, the development of congestive heart failure.

Adolescent↗
PubMed1998

Supersaturation and stone composition in a network of dispersed treatment sites.

PURPOSE: We determined the validity of urine supersaturation assessed from 2, 24-hour urine collections from outpatients eating uncontrolled diets and receiving care at a network of treatment sites that uses a central laboratory. We compared supersaturation to stone composition to determine whether supersaturation values correlate with composition. MATERIALS AND METHODS: Two 24-hour urine samples collected from 183 patients at 6 treatment sites were shipped to a single central laboratory. Complexations and crystallizations in vitro from aging during the transport step were interrupted by pH change in acid and alkaline directions. Relevant analytes were measured, and supersaturation was calculated for calcium oxalate, calcium phosphate as brushite and uric acid. Stone analysis was done at various laboratories. RESULTS: Urine supersaturation values correlated well with stone composition. Higher calcium phosphate and uric acid supersaturation was noted when stones contained higher amounts of calcium phosphate and any uric acid, respectively. In a validation study values of relevant urine materials were unchanged after 48 hours of aging. CONCLUSIONS: Despite the need for sample transport, resulting in the inevitable aging of samples, and variations in diet and details of sample collection, supersaturation values measured in only 2, 24-hour urine collections accurately reflected stone composition. This finding indicates that supersaturation values are reasonably stable in most patients during the months to years required for stones to form. In addition, samples collected in standard practice settings and sent to a central laboratory may accurately reflect these supersaturation values.

Calcium Oxalate↗
PubMed1998

Mutations in GDI1 are responsible for X-linked non-specific mental retardation.

Rab GDP-dissociation inhibitors (GDI) are evolutionarily conserved proteins that play an essential role in the recycling of Rab GTPases required for vesicular transport through the secretory pathway. We have found mutations in the GDI1 gene (which encodes uGDI) in two families affected with X-linked non-specific mental retardation. One of the mutations caused a non-conservative substitution (L92P) which reduced binding and recycling of RAB3A, the second was a null mutation. Our results show that both functional and developmental alterations in the neuron may account for the severe impairment of learning abilities as a consequence of mutations in GDI1, emphasizing its critical role in development of human intellectual and learning abilities.

Brain↗
PubMed1998

Principles and applications of laser lithotripsy: experience with the holmium laser lithotrite.

INTRODUCTION AND OBJECTIVES: The initial clinical experience with holmium laser energy applied for endoscopic lithotripsy was positive. The current study is presented as a contrast to the preliminary findings and as a means of defining the clinical usefulness of this specific laser lithotrite. MATERIALS AND METHODS: Calculi were treated endoscopically with the holmium laser lithotriptor and data was gathered prospectively. The youngest patient in the series was a thirteen-month--old who underwent percutaneous therapy, while the youngest patient on whom a retrograde endoscopic procedure was performed was a six-year old male patient with a proximal ureteral calculus. Lower water density, quartz fibers delivery systems were developed and employed. Fiber diameters ranged from 200-1000 micrograms. The smaller fibers were employed most commonly through the actively deflectable, flexible endoscope to facilitate treatment with maximum deflection. Larger fibers, with their much larger vaporization bubbles, were used through rigid endoscopes to debulk large stone burdens. RESULTS: A total of 210 patients with 249 calculi were treated. All major stone compositions were treated with minimal variation in laser efficiency. All but three of 109 ureteral calculi were treated in a retrograde fashion to completion (i.e., "stone free") in one sitting (97%). One-hundred thirteen renal stone burdens were treated with the holmium laser; 99 of these were treated solely in a retrograde fashion. Of the latter, 79 (80%) required only a single session. The combination of the actively deflectable, flexible ureteroscope and the 200-micrograms fiber facilitated treatment to completion of 38 to 45 lower-pole caliceal calculi (85%). The success of ureteropyeloscopic lithotripsy with the holmium laser for all intrarenal calculi, including staged or second sitting for large complex stone burdens, was 90%. Sixteen percutaneous procedures (13 renal and 3 ureteral calculi) employed the holmium laser as an endoscopic lithotrite. All 28 patients with large bladder calculi with a mean diameter of 41.8 mm were treated to completion in one sitting. Complications from holmium laser energy, including postoperative ureteral stricture disease, were not encountered in this series. CONCLUSIONS: Holmium laser energy is uniquely suited to treat urinary calculi safely regardless of stone size, location, or metabolic composition, and has particular efficacy in complex clinical presentations.

Child↗
PubMed1998

Central nervous system involvement in patients with HCV-related cryoglobulinemia.

Central nervous system involvement was rarely described in patients with mixed cryoglobulinemia (MC). Most cases were reported before 1991, so these patients were not tested for hepatitis C virus (HCV) infection. However, two cases of cerebral ischemia in patients with HCV-related MC were recently reported. We describe three patients with chronic HCV and cryoglobulinemia, who complained of mild neurologic symptoms (dizziness, equilibrium impairment, monolateral hyposthenia, and defective sensitivity) which can be ascribed to central nervous system involvement. In all of these patients, brain magnetic resonance imaging showed multiple small hyperintensities compatible with ischemic lesions.

Brain Ischemia↗
PubMed1998

Adenosine deaminase and human reproduction: a comparative study of fertile women and women with recurrent spontaneous abortion.

PROBLEM: We have investigated the possible role of adenosine deaminase (ADA) genetic polymorphism in human fertility through a comparative study of couples with recurrent spontaneous abortion (RSA) and healthy puerperae. METHOD OF STUDY: Adenosine deaminase phenotype has been determined in 209 women with repeated episodes of unexplained spontaneous abortion (RSA) and their husbands, as well as in 115 healthy pregnant women from the population of Rome. An independent sample of 286 puerperae along with their newborn infants in the population of Penne was also studied. RESULTS: The proportion of carriers of ADA*2 allele, which is associated with the lowest enzymatic activity, is lower among women with RSA than among healthy pregnant women from the same population of Rome. Preliminary observations suggest a protective effect of ADA*2 against the development of autoantibodies in RSA. Such an effect seems to be mediated by an interaction with AB0 blood groups. In the population of Penne the proportion of women carrying ADA*2 allele is higher among those who have had two or more previously born children than among women with only one or no children. CONCLUSIONS: The data suggest that women carrying the ADA*2 allele are better protected against the spontaneous loss of embryos and have a higher fertility rate.

ABO Blood-Group System↗
PubMed1998

Coexistence of mitochondrial DNA and beta myosin heavy chain mutations in hypertrophic cardiomyopathy with late congestive heart failure.

OBJECTIVE: To investigate the possible coexistence of mitochondrial DNA (mtDNA) mutations in patients with beta myosin heavy chain (beta MHC) linked hypertrophic cardiomyopathy (HCM) who develop congestive heart failure. DESIGN: Molecular analysis of beta MHC and mtDNA gene defects in patients with HCM. SETTING: Cardiovascular molecular diagnostic and heart transplantation reference centre in north Italy. PATIENTS: Four patients with HCM who underwent heart transplantation for end stage heart failure, and after pedigree analysis of 60 relatives, eight additional affected patients and 27 unaffected relatives. A total of 111 unrelated healthy adult volunteers served as controls. Disease controls included an additional 27 patients with HCM and 102 with dilated cardiomyopathy. INTERVENTION: Molecular analysis of DNA from myocardial and skeletal muscle tissue and from peripheral blood specimens. MAIN OUTCOME MEASURES: Screening for mutations in beta MHC (exons 3-23) and mtDNA tRNA (n = 22) genes with denaturing gradient gel electrophoresis or single strand conformational polymorphism followed by automated DNA sequencing. RESULTS: One proband (kindred A) (plus seven affected relatives) had arginine 249 glutamine (Arg249Gln) beta MHC and heteroplasmic mtDNA tRNAIle A4300G mutations. Another unrelated patient (kindred B) with sporadic HCM had identical mutations. The remaining two patients (kindred C), a mother and son, had a novel beta MHC mutation (lysine 450 glutamic acid) (Lys450Glu) and a heteroplasmic missense (T9957C, phenylalanine (Phe)-->leucine (Leu)) mtDNA mutation in subunit III of the cytochrome C oxidase gene. The amount of mutant mtDNA was higher in the myocardium than in skeletal muscle or peripheral blood and in affected patients than in asymptomatic relatives. Mutations were absent in the controls. Pathological and biochemical characteristics of patients with mutations Arg249Gln plus A4300G (kindreds A and B) were identical, but different from those of the two patients with Lys450Glu plus T9957C(Phe-->Leu) mutations (kindred C). Cytochrome C oxidase activity and histoenzymatic staining were severely decreased in the two patients in kindreds A and B, but were unaffected in the two in kindred C. CONCLUSIONS: beta MHC gene and mtDNA mutations may coexist in patients with HCM and end stage congestive heart failure. Although beta MHC gene mutations seem to be the true determinants of HCM, both mtDNA mutations in these patients have known prerequisites for pathogenicity. Coexistence of other genetic abnormalities in beta MHC linked HCM, such as mtDNA mutations, may contribute to variable phenotypic expression and explain the heterogeneous behaviour of HCM.

Adult↗
PubMed1998

Retrograde ureteropyeloscopic treatment of 2 cm. or greater upper urinary tract and minor Staghorn calculi.

PURPOSE: Upper urinary tract calculi that are too large to treat with extracorporeal shock wave lithotripsy are most commonly cleared with percutaneous endoscopic techniques. In a select group of patients who were poor candidates for percutaneous nephrostolithotomy we used retrograde endoscopic lithotripsy, and define the safety and efficacy of this modality in treating large, noninfectious stone burdens (2 cm. or greater). MATERIALS AND METHODS: A total of 51 patients with 66 large (2 cm. or greater) upper urinary tract stones were chosen for retrograde ureteroscopic surgery. Many of these patients had co-morbid conditions that precluded or complicated standard percutaneous treatment. Lithotripsy was based on the application of small diameter fiberoptic ureteroscopes and the holmium laser lithotriptor. Specifically, the 200 micro. laser fiber was used when lower pole renal access was required. Successful therapy was defined as total fragmentation of a stone burden with creation of fine sand and 2 mm. or smaller debris. Second look endoscopy was commonly performed in select patients with large branched calculi or stone burdens in excess of 3 cm. to rule out and treat large residual fragments. RESULTS: Of 51 patients 48 were treated solely in a retrograde ureteroscopic manner and in 3 either failure of lower pole access or infectious material encountered on initial endoscopy led to conversion to more standard percutaneous techniques. In 34 of 45 renal (76%), and 20 of 21 ureteral (95%) complete ureteroscopic fragmentation of the respective stone burden was accomplished after a single session. Second look endoscopy defined significant residual fragments requiring additional endoscopic lithotripsy in 8 of 15 large renal (53%) and 1 of 3 complex ureteral stone burdens. Success, that is complete pulverization of the stone burden to fine dust and small 2 mm. fragments, increased to 41 of 45 renal (91%) and all 21 ureteral calculi after these second look procedures. One patient required a third session to treat completely an exceptionally large (6 cm.) renal stone burden composed of pure cystine, thus increasing the overall success rate for renal calculi to 93%. Six-month followup data were available for 25 patients with large calculi treated ureteroscopically, of whom 15 (60%) had completely clear imaging, 6 (24%) had small lower pole debris that was decreasing on serial imaging and 4 (16%) had new stone growth which was, in part, related either to uncorrectable metabolic disorders or chronic renal scarring and urinary stasis. There were no intraoperative complications. Three postoperative complications included pyelonephritis in 1 patient, prostatic bleeding in 1 on anticoagulant therapy and a cerebral vascular accident 24 hours after the procedure in 1 with severe vascular disease. CONCLUSIONS: Large and complex upper urinary tract calculi can be addressed safely and efficiently with retrograde endoscopic techniques.

Adolescent↗
PubMed1998

Medical reduction of stone risk in a network of treatment centers compared to a research clinic.

PURPOSE: We determined whether a network of 7 comprehensive kidney stone treatment centers supported by specialized stone management software and laboratory resources could achieve reductions in urine supersaturation comparable to those in a single research clinic devoted to metabolic stone prevention. MATERIALS AND METHODS: Supersaturation values for calcium oxalate, calcium phosphate and uric acid in 24-hour urine samples were calculated from a set of kidney stone risk factor measurements made at a central laboratory site for the network and research laboratory for the clinic. Individual results and group outcomes were presented to each center in time sequential table graphics. The decrease in supersaturation with treatment was compared in the network and clinic using analysis of variance. RESULTS: Supersaturation was effectively reduced in the network and clinic, and the reduction was proportional to the initial supersaturation value and increase in urine volume. The clinic achieved a greater supersaturation reduction, higher fraction of patient followup and greater increase in urine volume but the treatment effects in the network were, nevertheless, substantial and significant. CONCLUSIONS: Given proper software and laboratory support, a network of treatment centers can rival but not quite match results in a dedicated metabolic stone research and prevention clinic. Therefore, large scale stone prevention in a network system appears feasible and effective.

Adult↗