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M Rossi

Publications and source records attributed to M Rossi.

At least 379 records · Page 21Linked to original sources
PubMed1995

[Long-term survival of patients with inoperable hepatocarcinoma, treated with interventional radiology].

Survival rates in untreated patients with unresectable HCC are rather disappointing. Our study was aimed at assessing long-term survival in the patients submitted to combined transarterial chemoembolization (TACE) and percutaneous ethanol injection (PEI). We treated 223 patients, but long-term follow-up is available in 143 of them only. Eighty-seven of 143 patients had Child's A liver cirrhosis, 45 had Child's B and 6 Child's C. Five patients did not have cirrhosis. Eighty-seven patients had single lesions--45 of them < 5 cm and 42 > 5 cm. Fifty-six patients had multiple/diffuse lesions. All patients underwent TACE while PEI was performed in selected patients with single or double lesions. Survival rates were calculated with the life-table analysis by Kaplan and Meyer. Follow-up was 1-72 months (median: 28 months). At 1, 3 and 5 years, the overall survival rates were 72%, 34.5% and 16.4%, respectively. The survival rates at 1, 3 and 5 years in single lesions < 5 cm were 90.4%, 52.1% and 34.8%, respectively, vs. 69.4%, 37.4% and 18.7% in lesions > 5 cm and 58.8%, 12.5% and 0% in multiple/diffuse lesions. In conclusion, the long-term results of the radiologic treatment of unresectable HCC are comparable with surgical results obtained in selected cases.

Actuarial Analysis↗
PubMed1995

Managing ascites via the Tenckhoff catheter.

Ascites is a serious and uncomfortable symptom experienced by a significant percentage of cancer patients. The use of the Tenckhoff catheter provides rapid relief of the mechanical effects of ascites. When this technology is used in the hospital or in the home, nurses act to prevent complications and inform patients and families about safety and other issues.

Ascites↗
PubMed1995

Thoracoscopic bilateral splanchnicotomy for pain control in unresectable pancreatic cancer.

Abdominal pain is the most common symptom of unresectable pancreatic carcinoma. The pancreas receives sympathetic and parasympathetic nerve fibers. The latter, which are the sensitive ones, reach the pancreas through the greater and lesser splanchnic nerve and the celiac ganglion. The greater splanchnic nerve originates from the thoracic ganglia T5-T8 and the lesser splanchnic nerve from T9-T11. The splanchnic nerves are composed of white nerve branches which stem from the ganglia, situated in the intercostal spaces, in the dorsal subpleural region, so they are easily visible through the pleura. The surgical treatment of pain in unresectable pancreatic carcinomas includes abdominal resection of splanchnic nerves, abdominal celiac and superior mesenteric ganglionectomy or thoracic resection of post-ganglionic splanchnic branches. Only recently monolateral thoracoscopic splanchnicotomy in association with vagotomy has been recommended. Because only the bilateral resection of splanchnic nerves ensures total control of pancreatic pain, the Authors have tried an original technique of bilateral thoracoscopic splanchnicotomy. The operation is performed in sequence on the two sides, with the patient lying, on the contralateral side. The lung is excluded and three 10 mm thoracic trocars are inserted: one in the 7th space on the median axillary line (for the optic), one in the 6th space on the posterior axillary line and one in the 5th space on the anterior axillary line. The pleura is opened medially to the sympathetic trunk, at the level of the 5th intercostal space and splanchnicotomy is performed downward up to the 11th intercostal space. The drains, placed through the previously-prepared opening at the level of the 7th intercostal space, are removed on 1 post-operative day. A bilateral thoracoscopic splanchnicotomy should be recommended as treatment of choice of pancreatic pain in unresectable pancreatic carcinoma, because is well tolerated by patients and ensures excellent results in terms of pain control.

Abdominal Pain↗
PubMed1994

Elimination of twinning in crystals of Sulfolobus sofataricus alcohol dehydrogenase holo-enzyme by growth in agarose gels.

Crystals of the binary complex of alcohol dehydrogenase from Sulfolobus solfataricus with NADH were shown to be twinned and not suitable for automated data collection. Several crystallization trials, performed with the aim of eliminating twinning, are described. Interestingly, crystals grown from agarose gel have been demonstrated to have a unique reciprocal lattice. These crystals are monoclinic, space group C2, with cell dimensions a = 134.47 (9), b = 85.26 (5), c = 71.76 (8) A, beta = 97.53 (4) degrees, and showed significant diffraction beyond 3.0 A resolution.

Journal Article↗
PubMed1994

A few amino acid substitutions are responsible for the higher thermostability of a novel NAD(+)-dependent bacillar alcohol dehydrogenase.

The gene adh-hT encoding a thermostable and thermophilic NAD(+)-dependent alcohol dehydrogenase (ADH) from the novel and more thermophilic Bacillus stearothermophilus LLD-R strain was cloned and its nucleotide sequence determined. The deduced protein sequence shows remarkable amino acid substitutions when compared to the sequence of the protein isolated from strain NCA1503 and significant similarity with the highly thermostable ADH from the thermoacidophilic archaebacterium Sulfolobus solfataricus. The alignment of these sequences led to the identification of three amino acid replacements probably responsible for the higher thermostability of the novel bacillar ADH. Adh-hT gene expression in Escherichia coli, a fast purification procedure and the characterization of the recombinant enzyme are also described.

Alcohol Dehydrogenase↗
PubMed1994

Purification and characterization of a thermostable carboxylesterase from the thermoacidophilic eubacterium Bacillus acidocaldarius.

A thermostable carboxylesterase from the thermoacidophilic eubacterium Bacillus acidocaldarius was isolated, purified 1800-fold to homogeneity, and characterised. The apparent molecular mass was 36.5 +/- 2.5 kDa when determined by SDS/PAGE and 37.5 kDa when determined by analytical gel filtration, suggesting a monomeric structure. The pure enzyme regained activity on removal of SDS after SDS/PAGE. Several esterase activities were revealed in crude extracts by PAGE and activity staining, although only one was detected after SDS/PAGE and detergent removal. The esterase showed optimal activity at around 70 degrees C and pH 8, and was thermostable. p-Nitrophenyl esters of fatty acids from C2 to C12 were used as substrates; Vmax and Km values were determined at three different temperatures. The enzyme was able to hydrolyse tributyrylglycerol and trihexanoyl-glycerol dissolved in 0.8% acetonitrile, but neither lipase activity toward [14C]trioleoylglycerol nor proteolytic activity could be detected. Inactivation by diethyl p-nitrophenyl phosphate, by phenyl-methansulfonyl fluoride and physostigmine, and by diethylpyrocarbonate suggested that the enzyme contained a catalytic triad Ser-His-Asp/Glu in the active site, similar to that demonstrated for other serine-type enzymes. The amino acid composition and the sequence of 19 amino acid residues at the N-terminus were determined. These data, together with substrate preference and inhibition pattern, allowed us to classify this enzyme as a B-type carboxylesterase (EC 3.1.1.1).

Amino Acid Sequence↗
PubMed1994

Evidence that an archaeal alpha-like DNA polymerase has a modular organization of its associated catalytic activities.

In this study we report on the evidence that an alpha-like DNA polymerase purified from the thermoacidophilic archaeon Sulfolobus solfataricus has a modular organization of its associated catalytic activities (polymerase and 3'-5' exonuclease). This enzyme, a monomer of about 100 kDa whose complete primary structure is available, has a protease hypersensitive site that is likely to be cleaved by the action of endogenous proteases during the purification procedure. As a consequence of that, two proteolytic fragments of about 50 and 40 kDa, in addition to the intact 100-kDa molecular species, can be detected upon SDS-PAGE of highly purified S. solfataricus DNA polymerase samples. The amino-terminal microsequence analysis by Edman degradation has revealed that the 50- and the 40-kDa polypeptides correspond to the carboxyl- and the amino-terminal portion of the protein molecule, respectively. Using the bidimensional activity gel assay procedure, recently described by Longley and Mosbaugh (Longley, M. J., and Mosbaugh, D. W. (1991) Biochemistry 30, 2655-2664), we have demonstrated that the 50-kDa fragment retains a Mg(2+)-dependent DNA polymerizing activity, whereas the 40-kDa polypeptide is able to catalyze the excision of mispaired nucleotides at the 3'-OH terminus of a primer/template DNA substrate in the presence of Mn2+ ions. On the other hand, the 100-kDa protein possess both activities. To date, this is the first report indicating, on the basis of direct functional data, that the polymerization and the 3'-5' exonuclease activity of a family B DNA polymerase can be ascribed to physically distinct modules of the enzyme molecule.

Amino Acid Sequence↗
PubMed1994

Differences in abuse reported by female and male Canadian medical students.

OBJECTIVE: To assess differences between male and female medical students concerning their experiences of abuse during training in a large Canadian medical school. DESIGN: Voluntary, anonymous cross-sectional survey of first- and fourth-year medical students during February 1991. SETTING: University of Toronto School of Medicine. PARTICIPANTS: Of 396 first- and fourth-year students surveyed after one of their regular classes, 347 (117 women, 230 men) completed the questionnaire. INTERVENTION: A 165-item, multiple-choice questionnaire concerning experiences of verbal or emotional abuse, sexual harassment and physical abuse, completed within 30 minutes. MAIN OUTCOME MEASURES: Differences between male and female respondents in abuse experiences before and during medical training, the relation between abuse before and during training, and the psychologic and behavioural effects of abuse during training. RESULTS: The experiences of the male and female respondents differed mainly in regard to sexual harassment: 42% (49/117) of the women and 11% (25/230) of the men reported sexual harassment before entering medical school (p < 0.0001); 46% (54/117) and 19% (43/230) respectively reported sexual harassment during medical training (p < 0.0001); and women who reported sexual harassment were the only respondents for whom a significant relation was found between abuse before and during training (p < 0.043). The women were more distressed than the men by all forms of abuse. A significant relation was shown between male students who reported experiencing abuse during medical training and mistreating patients (p < 0.0001). CONCLUSION: Female students' experiences of sexual harassment differed from those of their male counterparts. As well, the female students' reactions to and ways of coping with all types of abuse differed from those of the male students.

Adaptation, Psychological↗
PubMed1994

The chaperonin from the archaeon Sulfolobus solfataricus promotes correct refolding and prevents thermal denaturation in vitro.

We have isolated a chaperonin from the hyperthermophilic archaeon Sulfolobus solfataricus based on its ability to inhibit the spontaneous refolding at 50 degrees C of dimeric S. solfataricus malic enzyme. The chaperonin, a 920-kDa oligomer of 57-kDa subunits, displays a potassium-dependent ATPase activity with an optimum temperature at 80 degrees C. S. solfataricus chaperonin promotes correct refoldings of several guanidine hydrochloride-denatured enzymes from thermophilic and mesophilic sources. At a molar ratio of chaperonin oligomer to single polypeptide chain of 1:1, S. solfataricus chaperonin completely inhibits spontaneous refoldings and suppresses aggregation upon dilution of the denaturant; refoldings resume upon ATP hydrolysis, with yields of active molecules and rates of folding notably higher than in spontaneous processes. S. solfataricus chaperonin prevents the irreversible inactivations at 90 degrees C of several thermophilic enzymes by the binding of the denaturation intermediate; the time-courses of inactivations are unaffected and most activity is regained upon hydrolysis of ATP. S. solfataricus chaperonin completely prevents the formation of aggregates during thermal inactivation of chicken egg white lysozyme at 70 degrees C, without affecting the rate of activity loss; ATP hydrolysis results in the recovery of most lytic activity. Tryptophan fluorescence measurements provide evidence that S. solfataricus chaperonin undergoes a dramatic conformational rearrangement in the presence of ATP/Mg, and that the hydrolysis of ATP is not required for the conformational change. The ATP/Mg-induced conformation of the chaperonin is fully unable to bind the protein substrates, probably due to disappearance or modification of the substrate binding sites. This is the first archaeal chaperonin whose involvement in protein folding has been demonstrated.

Adenosine Triphosphatases↗
PubMed1994

Interaction of the high-affinity inhibitor tetrahydro-dUMP with the allosteric enzyme deoxycytidylate aminohydrolase.

Tetrahydro-dUMP, an analog of the putative transition state in aminohydrolysis of deoxycytidine monophosphate (dCMP) inhibits the allosteric enzyme deoxycytidylate aminohydrolase with high affinity. The inhibition is reversible, and its kinetics is consistent with the analog binding at the substrate site only to one and the same conformation that binds the substrate dCMP. Such kinetics is what would be expected for a transition state analog interacting in an allosteric "K system."

Allosteric Regulation↗
PubMed1994

Influence of fat on ultrasound measurements of the os calcis.

Measurements of the speed-of-sound (SOS) and of the broadband ultrasound attenuation (BUA) on the os calcis were recently proposed to assess osteoporotic fragility. Velocity and attenuation were measured through the heel which can be divided in three phases including hydroxyapatite, soft tissue, and fat. The aim of this study was to evaluate the influence of fat composition and heel width on SOS and BUA. This influence was determined from both in vitro investigations examining fat samples, phantoms, and cadaver heels, and in vivo ones observing adult volunteers as well as a wide sample section of healthy elderly women. Ultrasound velocities on various fat samples were significantly lower than those on distilled water (-65 m/second to -123 m/second). The excision of the surrounding soft tissue from cadaver heels made SOS steadily increase whereas the insertion of a 10 mm piece of lard in the lateral face of cadavers' and volunteers' heels os calcis lowered SOS about 30 m/second. Furthermore, a difference of SOS was estimated at 15 m/second for a 12.5% variation of the marrow fat weight. Among 334 elderly and healthy women aged 75 and over, a significant negative correlation was found between SOS and heel width (r = -0.27; P < 0.0001). On the other hand, fat composition had no significant effect on BUA measurement, and no significant relationship was found between BUA and heel width. This study demonstrates that an increase of heel width and fat thickness provides an underestimation of os calcis SOS, but has no significant effect on BUA.

Adipose Tissue↗
PubMed1994

Alternative laparoscopic management of perforated peptic ulcers.

Surgery--namely, suture closure-is still the treatment of choice for perforated peptic ulcers, despite the proven efficacy of Taylor's conservative approach. Such conservative management, however, has been proven less effective in high-risk patients and those with perforations more than 12 h old. Here we suggest alternative laparoscopic treatments for perforated peptic ulcers. We have treated laparoscopically six patients (one F, five M; mean age 57.6 years; range 31-81 years); the mean duration of the operation was 52 min; the median hospital stay was 7 days (6-15 days); H2-blockers, antibiotics, and fluids were administered in the p.o. course; the follow-ups range from 6 to 18 months. On the basis of our experience, the treatment of choice for perforated peptic ulcers is Taylor's conservative procedure and laparoscopic drainage of the abdominal cavity when there is mild peritoneal reaction (usually less than 6 h from the onset of perforation). In case of remarkable peritonitis (usually more than 12 h), it is mandatory to add an accurate lavage. When the site of perforation is concealed by the peritoneal inflammation it should not be searched; when visible, it might be obliterated with the round ligament or an omental tissue strand, particularly if larger than 1 cm in diameter.

Adult↗
PubMed1994

Mosaic regulation of lactase in human adult-type hypolactasia.

BACKGROUND/AIMS: We have previously shown that in the proximal-jejunum of hypolactasic humans, just a few villus enterocytes express lactase protein and activity. In the present study, we compared the distribution of lactase messenger RNA (mRNA), protein, and activity in villus enterocytes in tissues obtained from subjects with persistent high lactase activity and those with hypolactasia. METHODS: Immunohistochemical and enzymohistochemical staining was performed on closely adjacent sections of human proximal jejunum from 5 individuals with persistent high lactase activity and 32 with hypolactasia. In all the persistent and in 9 hypolactasic samples, in situ hybridization was also performed using a digoxygenin-labeled RNA probe. RESULTS: In persistent tissues, lactase mRNA, protein, and activity were present in all villus enterocytes. In hypolactasic tissues, lactase mRNA was detected only in some villus enterocytes; some of them also expressed protein and activity, whereas others did not. In 8 of these hypolactasic samples, a variable number of villus enterocytes with lactase mRNA and protein did not express lactase activity. CONCLUSIONS: Various types of enterocytes are present even on a single villus from individuals with adult-type hypolactasia. These results show that different mechanisms control lactase expression in enterocytes on the same villus.

Adult↗
PubMed1994

Rush desensitization in heparin hypersensitivity: a case report.

Among all the known drug intolerances, adverse reactions to heparin are not very common. No desensitization in patients with heparin hypersensitivity has ever been attempted. We report the case of a 55-year-old female patient with mitral stenosis and insufficiency, and tricuspid and aortic insufficiency. The patient underwent heparin treatment, and urticaria occurred with either s.c. calcium heparin or i.v. sodium heparin. Allergy testing (skin tests and patch tests) was negative. A pseudoallergic intolerance was diagnosed. Mitral valve replacement with the extracorporeal circulation method was necessary; therefore, heparin treatment was administered. A heparin rush desensitization together with antihistamine drugs (4 mg clorpheniramine maleate for 3 d) was started: 50 UI (0.5 mg) s.c. sodium heparin were first administered; within 4 d, 5000 UI (50 mg) sodium heparin was administered i.v. with no side-effects. A full-dosage heparin treatment was then administered and heart surgery was easily performed. During the postsurgical course, i.v. sodium heparin was smoothly replaced with s.c. calcium heparin (25,000 UI s.c. per day) and with oral anticoagulants (sodium warfarin).

Chlorpheniramine↗
PubMed1994

Morphological method for the diagnosis of human adult type hypolactasia.

The primary adult type hypolactasia is the most common form of genetically determined disaccharidase deficiency. This study examined a large and homogeneous population of the south of Italy: surgical biopsy specimens of proximal jejunum from 178 adult subjects have been assayed for disaccharidase activities; the expression of lactase protein and lactase activity has also been investigated on tissue sections by immunomorphological and enzymohistochemical techniques. Histograms of lactase to sucrase ratio were found to provide a useful distribution of the lactase activity; a lactase to sucrase ratio of 0.17 was found to show discrimination between tissues with persistence of high lactase activity and tissues with adult type hypolactasia. In all 28 subjects with persistent high lactase activity, a uniform distribution of lactase protein and lactase activity in all villus enterocytes was detected, whereas in all 150 subjects with adult type hypolactasia a variable number of villus enterocytes failed to express the lactase. Moreover in hypolactasic samples the lactase activity on tissue sections was constantly detected later than in samples with persistent high lactase activity. The absolute correlation between the immunohistochemical and enzymohistochemical features and the assessment of lactase activity in intestinal homogenates suggests that the morphological criteria are an alternative method for the diagnosis of adult type hypolactasia in human biopsy specimens from proximal small jejunum.

Adult↗
PubMed1994

Hemodynamic changes after transcatheter arterial embolization of hepatocellular carcinomas.

PURPOSE: To evaluate the serial hemodynamic changes that occur after transcatheter arterial embolization (TAE) of hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: Twenty patients with HCCs treated with TAE were evaluated with color and duplex Doppler sonography before, immediately after, and 2 days after TAE. The changes in hepatic artery and portal vein velocity and flow were evaluated. RESULTS: The portal venous velocity and flow did not change significantly after TAE. The peak systolic velocity in the proximal hepatic artery decreased significantly (P < .01) immediately after TAE then returned to baseline values 2 days after TAE; the resistance index of the proximal hepatic artery increased significantly (P < .01) immediately after embolization, then returned to baseline values 2 days after TAE. Arterial signal in the distal hepatic artery, generally absent immediately after TAE, could be recorded 2 days after. CONCLUSION: There is a rapidly reversible decrease in hepatic arterial flow induced by embolization, without any change in portal venous flow.

Adult↗