Ventricular tachycardia during hyperthermic intraperitoneal chemotherapy.

SUMMARY: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC) is used for selected gastrointestinal carcinomas. We report a case of ventricular tachycardia during HIPEC with cisplatin that persisted as long as the chemotherapy solution remained in the intra-abdominal cavity. We hypothesise that high plasma levels of cisplatin with concomitant low magnesium levels caused the arrhythmia.

Tacticity effects on the barriers to rotation of the ester methyl group in poly (methyl methacrylate): a deuteron magnetic resonance study.

In isotactic poly(methyl methacrylate) (PMMA), we investigate the dynamics of the ester methyl groups by means of deuteron magnetic resonance (DMR) in a deuterated sample. We find that the motion of the CD(3)-group affects the deuteron spin-lattice relaxation as well as the DMR line shape in a characteristic way. Quadrupolar order spin lattice relaxation measurements between T=291 K and T=70 K reveal a broad temperature dependent probability distribution of autocorrelation times tau(c) for the 2pi/3 reorientation. This broad distribution corresponds to a temperature independent Gaussian distribution of activation energies rho(E(a)) with variance sigma(E(a) )=13.8+/-0.5 meV (1.33 kJ/mol). The line shape transition between T=70 K and T=23 K is explained with the freezing in of the methyl group reorientation. By comparing our results in an 88% isotactic sample with results obtained from a 50% syndiotactic, 30% atactic, and 20% isotactic sample of a previous investigation, we demonstrate the higher local order of the 88% isotactic sample, which corresponds to a ratio of 1.6 in the relative width sigma(E(a) )/E(a) of the E(a) distribution. We show that different stereospecific forms of PMMA can be easily distinguished by the characteristics of their line shape transition between T=70 K and T=23 K.

Seismic images of crust and upper mantle beneath Tibet: evidence for Eurasian plate subduction.

Seismic data from central Tibet have been combined to image the subsurface structure and understand the evolution of the collision of India and Eurasia. The 410- and 660-kilometer mantle discontinuities are sharply defined, implying a lack of a subducting slab beneath the plateau. The discontinuities appear slightly deeper beneath northern Tibet, implying that the average temperature of the mantle above the transition zone is about 300 degrees C hotter in the north than in the south. There is a prominent south-dipping converter in the uppermost mantle beneath northern Tibet that might represent the top of the Eurasian mantle lithosphere underthrusting the northern margin of the plateau.

Risk assessment and prediction of rebleeding in bleeding gastroduodenal ulcer.

BACKGROUND AND STUDY AIMS: The aims of this study were to identify risk factors for recurrence of hemorrhage in bleeding gastroduodenal ulcers after endoscopic injection therapy, and to develop a simple and relevant prognostic score which could be used to assess the early risk of recurrence and the residual risk of rebleeding. PATIENTS AND METHODS: A prospective study was conducted from January 1995 to December 1998, in 738 patients who were admitted to our department for acute bleeding peptic ulcer and who underwent endoscopic examination. Ulcers with active bleeding or signs of recent bleeding were treated with injection therapy using epinephrine (1/10,000) and 1% polidocanol. RESULTS: Multivariate analysis revealed that liver cirrhosis, recent surgery, systolic blood pressure below 100 mmHg, hematemesis, Forrest classification, and ulcer size and site were significantly predictive variables for the recurrence of hemorrhage. Among these, Forrest classification was the most important. The overall accuracy of the predictive model was 71% (95% CI = 63 - 79%). The model showed a better sensitivity of 90% for early rebleeding (< 48 hours) than for late rebleeding (> or = 48 hours) where the sensitivity was 65 %. A prognostic score was obtained and patients were classified into four risk classes: very low (VL), low (L), high (H), and very high (VH). The rebleeding rates for the four classes were 0%, 7.9%, 31.8% and 67.9%, and the mortality rates were 5.9%, 8.6%, 13.9% and 35.7%, respectively. The residual risk of rebleeding after 48 hours was 0%, 3.3%, 10.4%, and 14.3% in the VL, L, H and VH classes, respectively. After 5 days the residual risk was under 4% in all classes. CONCLUSIONS: This study demonstrates that the proposed prognostic score, which is easily obtained after emergency endoscopy, is useful in clinical practice because it can identify patients with different levels of rebleeding risk. It can be helpful in patient management and decision making for discharge.

[Esophageal non-variceal hemorrhage: a clinical and epidemiological study]. / Le emorragie esofagee non varicose: studio clinico-epidemiologico.

Aim of this study was to evaluate the incidence of esophageal bleeding in a group of 3741 consecutive patients with acute non variceal upper gastrointestinal hemorrhage observed between January 1990 and January 1999 in the First Division of General Surgery--University of Verona. In 627 patients (16.8%) the source of bleeding was exclusively esophageal; and the most frequent causes of esophageal bleeding were reflux esopagitis (408 cases) and Mallory Weiss syndrome (185 cases). At emergency endoscopy, reflux esophagitis was actively bleeding in 83 cases (20.3%) and these patients presented a significantly higher frequency of cirrhosis and severe esophagitis; moreover a higher percentage of patients with bleeding esophagitis have had recent surgery and/or were hospitalized in an intensive care unit. No death directly related to the bleeding were observed, while ten patients deceased from other causes during the hospitalization. In more than half of the 185 patients affected by Mallory-Weiss syndrome a hiatal hernia was described and 69 (37.3%) were alcoholics with associated cirrhosis in 25 cases. In more than 70% of the cases the bleeding from a mucosal tear followed a vomit episode and the lesions were localized at the gastroesophageal junction. Endoscopic sclerotherapy was performed in 89 patients with active bleeding and hemostasis was initially obtained in all patients; rebleeding occurred in 6 patients (6.7%) who needed a further endoscopic treatment. No patients died during hospitalization. Other causes of esophageal bleeding observed were: Candida esophagitis (19 cases), esophageal malignancy (11 cases), benign polyps (2 cases), angiodysplasia (one case) and one case of aorto-esophageal fistula.

Endoscopic treatment of esophageal granular cell tumors.

There are no standard guidelines for the treatment of granular cell tumor (GCT). The aim of our study was to describe three cases of esophageal GCT and, on the basis of our experience, analyze the indications for and results of their endoscopic treatment. When deciding whether to proceed with surgical or endoscopic resection, endosonography plays a key role in establishing whether the tumor is confined to the submucosa. All three cases were confined within the hyperechoic layer of the submucosa and were successfully treated by endoscopic excision without complications or signs of relapse during the follow-up period.

[Peptic ulcer hemorrhage in the elderly]. / Le ulcere gastroduodenali sanguinanti nel paziente anziano.

BACKGROUND: The aim of this study was to investigate the efficacy of endoscopic injection therapy on the clinical outcome of elderly patients with peptic ulcer bleeding. METHODS: From January 1995 to December 1998, 738 patients with acute peptic ulcer bleeding were observed in the First Division of General Surgery, University of Verona: 359 aged <70 years and 379 =/>70 years. History, clinical and endoscopic findings and outcome were prospectively collected and analyzed comparing old (=/>70 yrs) and young (<70 yrs) patients. Ulcers with active or sign of recent bleeding were submitted to injection therapy using epinephrine and 1% polidocanol. RESULTS: Coexisting diseases were significantly more present in the elderly group except for liver cirrhosis that affected preferentially young patients (12.3 versus 4.0%; p<0.001). Endoscopic treatment was performed in a similar percentage between young and elderly patients (respectively 64.9 e 61.5%) and also the rebleeding rate (14.2 versus 13.2) and the mean duration of hospitalisation were not different. The overall mortality was 12.7% in the elderly group and 8.3% in the young group (p=0.04), whereas mortality after surgery was significantly higher in the young group (respectively 57.1 versus 8.3%; p=0.037). CONCLUSIONS: The clinical and endoscopic features and reebleeding rate were not different between elderly and young patients. Patients aged 70 years or older have a higher number of associated medical diseases except for liver cirrhosis conditions and a highest overall mortality whereas the risk of death after surgery is lower than in the younger group.

[Endoscopic, percutaneous and laparoscopic treatment for acute biliary pancreatitis]. / Traitement endoscopique, percutané et coelioscopique des pancréatites aiguës biliaires.

AIM OF THE STUDY: The aim of this study is to evaluate the results of acute gallstone pancreatitis treatment and to discuss indications in relation with the different forms of the disease. MATERIAL AND METHOD: From january 1992 to june 2001, 137 patients have been treated for an acute gallstone pancreatitis. Diagnostic criteria were given by the history, clinical examination, biochemical and radiological findings. After exclusion of patients with a systemic disease, a group of 129 patients have been enrolled in a treatment regimen with an endoscopic retrograde cholangiopancreatography (ERCP) and eventual sphincterotomy, a percutaneous US-guided cholecystostomy (PC) when necessary and an elective laparoscopic cholecystectomy. RESULTS: ERCP has been successfully performed in 121/129 patients. A PC has been performed in 5/8 patients of the failed endoscopic procedure and in 14 with acute cholecystitis. Retrograde and percutaneous cholangiographies showed main bile duct stones in 89 patients, a dilatation of the main bile duct without stones in 26 patients and a negative finding in 6 patients. An endoscopic sphincterotomy has been performed in 117 patients. A laparoscopic cholecystectomy has been performed in 118 patients. Mortality and morbidity rates were 1.6 and 10.3%, respectively. CONCLUSION: ERCP and sphincterotomy seem to be indicated in all patients observed during the first 72 hours. Endoscopic treatment and percutaneous procedure make it possible to reduce at a very low rate the cases with an unfavourable course of the disease. A definitive treatment may then be performed by the way of a laparoscopic cholecystectomy.

[Acute hemorrhage caused by duodenal ulcer. Results of endoscopic treatment of the first bleeding episode and of recurrences]. / Emorragia acuta da ulcera duodenale. Risultati del trattamento endoscopico del primo sanguinamento e delle recidive.

BACKGROUND: The aim of this study was to evaluate the impact of immediate endoscopic treatment of bleeding and rebleeding on the clinical outcome of patients with duodenal ulcer hemorrhage. MATERIALS AND METHODS: Between January 1995 and December 1998, 445 patients with bleeding duodenal ulcers were observed in the First Division of General Surgery--University of Verona. All patients, except two who died for hemorrhage before the endoscopic examination, underwent emergency endoscopy within 2 hours from the admission and ulcers with active or sign of recent bleeding were submitted to injection therapy. History, clinical and endoscopic findings, recurrent bleeding and outcome were prospectively collected and analyzed. Recurrent bleeding underwent immediate endoscopic retreatment as first attempt. RESULTS: Endoscopic therapy was performed in 277 patients with active bleeding and hemostasis was initially obtained in all patients except one. Rebleeding occurred in 62 patients (14%) and endoscopic treatment was successful in 85% of first rebleeding and in 58% of the cases with 2 or more rebleeding. Multivariate analysis showed that systolic blood pressure at admission, ulcer size and Forrest classification influenced independently the recurrence rate. The 30 days mortality was 12.2% in the whole series: 35 deaths (9.2%) in the group without recurrence and 19 (30.6%) deaths in the rebleeding group (p = 0.001). Only 22 patients (5%) underwent surgical treatment with a higher mortality compared to not operated patients (36.4% versus 10.9%). CONCLUSIONS: Endoscopic treatment was associated with reductions of the risk of recurrent bleeding and surgery without increasing mortality rate.

Phonon-assisted spin diffusion in solids

The spin flip-flop transition rate is calculated for the case of spectral spin diffusion within a system of dipolarly coupled spins in a solid where the lattice vibrations are present. Long-wavelength acoustic phonons time-modulate the interspin distance r(ij) and enhance the transition rate via the change of the 1/r(3)(ij) term in the coupling dipolar Hamiltonian. The phonon-assisted spin diffusion rate is calculated by the golden rule in the Debye approximation of the phonon density of states. The coupling of the spins to the phonons introduces temperature dependence into the transition rate, in contrast to the spin diffusion in a rigid lattice, where the rate is temperature-independent. The direct (one-phonon absorption or emission) processes introduce a linear temperature dependence into the rate at temperatures not too close to T = 0. Two-phonon processes introduce a more complicated temperature dependence that again becomes simple analytical for temperatures higher than the Debye temperature, where the rate is proportional to T(2), and in the limit T --> 0, where the rate varies as T(7). Raman processes (one-phonon absorption and another phonon emission) dominate by far the phonon-assisted spin flip-flop transitions. Copyright 2000 Academic Press.

Bucrylate treatment of bleeding gastric varices: 12 years' experience.

BACKGROUND AND STUDY AIMS: For several years now there has been an increasingly widespread use of a tissue adhesive in the treatment of bleeding gastric varices to achieve rapid, safe control of hemostasis and prevent rebleeding. In this study we report on our experience with the use of Bucrylate (Hystoacryl) for the treatment of gastric varices over a period of more than a decade. PATIENTS AND METHODS: Since 1988, 174 cirrhotic patients with actively bleeding gastric varices have been admitted to our department, where they received emergency treatment with injections of Bucrylate. Any associated nonbleeding esophageal varices were subjected to traditional sclerotherapy in combination with the Bucrylate treatment. The gastric varices were subdivided into four distinct groups according to the method advocated by Sarin in 1989. The patients underwent weekly sclerotherapy sessions until their varices were eradicated, and the follow-up with a mean of 36 months (range 9-90 months) consisted of endoscopy at 3, 6, and 12 months during the first year and then yearly checks to confirm obliteration of the varices. RESULTS: The hemostasis (97.1%), early rebleeding (15.5%), and hospital mortality (19.5%) rates of the patients with bleeding gastric varices, treated with the tissue adhesive, were very similar to those of patients treated for esophageal varices over the same period (98.1%, 13.0%, and 16.4%, respectively). The most frequent cause of death at 30 days was liver failure (76% of cases), followed by hemorrhagic shock (8.8%), and other less frequent causes. Sclerotherapy achieved obliteration rate for gastric varices (70-75%) similar to that for esophageal varices in those patients with portal hypertension due to intrahepatic block (alcoholic and posthepatitis cirrhosis), but a rate of only 32% in the group of patients with prehepatic block (splenoportomesenteric thrombosis), where surgery proved more effective (69%). The medium- and long-term survival rates depended on the stability of the patients' liver conditions, on rapid, effective control of variceal hemostasis, and on complete, lasting obliteration of the gastric varices. CONCLUSIONS: The use of Bucrylate in emergency sclerotherapy achieved results in bleeding gastric varices on a par with those obtained in esophageal varices in cases of alcoholic and posthepatitis cirrhosis. The group of patients with portal hypertension due to prehepatic block (splenoportal thrombosis) showed no benefit from sclerotherapy in terms of obliteration of gastric varices, but benefited from elective surgery. The choice of the obliterating treatment indicated may be facilitated by classifying gastric varices into distinct groups on the basis of anatomicotopographic criteria.

Mapping the Hawaiian plume conduit with converted seismic waves

The volcanic edifice of the Hawaiian islands and seamounts, as well as the surrounding area of shallow sea floor known as the Hawaiian swell, are believed to result from the passage of the oceanic lithosphere over a mantle hotspot. Although geochemical and gravity observations indicate the existence of a mantle thermal plume beneath Hawaii, no direct seismic evidence for such a plume in the upper mantle has yet been found. Here we present an analysis of compressional-to-shear (P-to-S) converted seismic phases, recorded on seismograph stations on the Hawaiian islands, that indicate a zone of very low shear-wave velocity (< 4 km s(-1)) starting at 130-140 km depth beneath the central part of the island of Hawaii and extending deeper into the upper mantle. We also find that the upper-mantle transition zone (410-660 km depth) appears to be thinned by up to 40-50 km to the south-southwest of the island of Hawaii. We interpret these observations as localized effects of the Hawaiian plume conduit in the asthenosphere and mantle transition zone with excess temperature of approximately 300 degrees C. Large variations in the transition-zone thickness suggest a lower-mantle origin of the Hawaiian plume similar to the Iceland plume, but our results indicate a 100 degrees C higher temperature for the Hawaiian plume.

Subduction and collision processes in the Central Andes constrained by converted seismic phases.

The Central Andes are the Earth's highest mountain belt formed by ocean-continent collision. Most of this uplift is thought to have occurred in the past 20 Myr, owing mainly to thickening of the continental crust, dominated by tectonic shortening. Here we use P-to-S (compressional-to-shear) converted teleseismic waves observed on several temporary networks in the Central Andes to image the deep structure associated with these tectonic processes. We find that the Moho (the Mohorovicic discontinuity--generally thought to separate crust from mantle) ranges from a depth of 75 km under the Altiplano plateau to 50 km beneath the 4-km-high Puna plateau. This relatively thin crust below such a high-elevation region indicates that thinning of the lithospheric mantle may have contributed to the uplift of the Puna plateau. We have also imaged the subducted crust of the Nazca oceanic plate down to 120 km depth, where it becomes invisible to converted teleseismic waves, probably owing to completion of the gabbro-eclogite transformation; this is direct evidence for the presence of kinetically delayed metamorphic reactions in subducting plates. Most of the intermediate-depth seismicity in the subducting plate stops at 120 km depth as well, suggesting a relation with this transformation. We see an intracrustal low-velocity zone, 10-20 km thick, below the entire Altiplano and Puna plateaux, which we interpret as a zone of continuing metamorphism and partial melting that decouples upper-crustal imbrication from lower-crustal thickening.

[Mallory-Weiss syndrome. Outcome of 160 cases]. / La sindrome di Mallory-Weiss. Risultati su 160 casi.

The Mallory-Weiss (M-W) syndrome is responsible for about 7.5% of all bleedings of oesophageal origin. Emergency endoscopic treatment allows to obtain a rapid diagnosis as well as an effective treatment. Personal experience on 160 cases of M-W tears (14.2% of all oesophageal bleeding) is reported. The tears were classified in three groups: IA and IB (30 cases); IIA and IIB (48 cases); IIC and III (82 cases). In the first two groups a complete haemostasis was obtained in 73 out of 78 cases (93.6%) with a single session and in 5/78 cases with two sessions of sclerotherapy. The third group was treated with medical therapy. There was no procedure related mortality. An analysis of etiologic factors, anatomic conditions and pathogenetic correlations has highlighted the role of portal hypertension in cirrhotic patients in favouring the bleeding in some of these patients and the role of hiatal hernia and cardial incontinence in determining the site of the lesions.

87Rb spin diffusion in ferroelectric RbH2PO4 studied by two dimensional exchange NMR

We separate the contributions of spectral spin diffusion and chemical exchange in the 2D exchange NMR spectra of 87Rb in the pseudo-spin glass Rb1-x(ND4)xD2PO4 by studying the 87Rb spin diffusion in the isostructural compound RbH2PO4 at 85K, where the system is frozen in the ferroelectric phase state. The fact that the spin-diffusion time (TSD) of a particular point in the 2D spectrum depends essentially on its distance from the diagonal, allowed, even for the case of an unresolved 2D spectrum, to determine TSD as a function of the frequency separation Delta over two orders of magnitude. In accordance with existing theories, T-1SD(Delta) was found to be of Gaussian shape. However, we found huge discrepancies between the calculated and the experimentally determined second moments. This failure of the theory is not understood at present. Copyright 1999 Academic Press.

Seismic Evidence for a Detached Indian Lithospheric Mantle Beneath Tibet.

P-to-S converted teleseismic waves recorded by temporary broadband networks across Tibet show a north-dipping interface that begins 50 kilometers north of the Zangbo suture at the depth of the Moho (80 kilometers) and extends to a depth of 200 kilometers beneath the Bangong suture. Under northern Tibet a segmented south-dipping structure was imaged. These observations suggest a different form of detachment of the Indian and Asian lithospheric mantles caused by differences in their composition and buoyancy.

Endoscopic clipping of anastomotic leakages in esophagogastric surgery.

BACKGROUND AND STUDY AIMS: Anastomotic leakage is a severe complication in gastric surgery and it is associated with a high rate of mortality. Conservative treatment sometimes is not sufficient to stem the leakages and, even when it is sufficient, it takes a long time. The present study describes the first experience in the treatment of anastomotic leakages with endoscopic clipping. PATIENTS AND METHODS: From May 1995 to December 1996, seven patients with postoperative anastomotic leakages after gastric surgery were prospectively treated in our Endoscopy Service. Metallic endoclips (MD 850, Olympus Corp., Tokyo, Japan) with prongs 12 mm long and 6 mm wide were applied, controlling the closure of the leakage by endoscopy, using radiographs to confirm the closure 24 hours later. RESULTS: Complete closure of the leakage was obtained in all seven cases. A single session of endoscopic clipping was needed for five patients while two other required, respectively, two and three sessions. The median time of leakage closure after endoscopic clipping was 2.3 days (range 1-5 days). The clips spontaneously dislodged within 1 month in five patients and within the second month in the other two patients. CONCLUSION: Endoscopic treatment of anastomotic leakages by metallic clips represents a safe and easily repeated method and, compared to conservative treatment, it seems to offer several time and cost advantages. Further studies involving a larger number of patients are needed to verify this finding.

Minimally invasive treatment of acute biliary pancreatitis.

BACKGROUND: Stones of the common bile duct are the most important factor in acute pancreatitis (AP). Endolaparoscopic surgery plays a well-recognized role in the treatment of this pathology. METHODS: From January 1992 to December 1995 we observed 62 cases of acute biliary pancreatitis (ABP). In 57 cases (= 93.4%) we proposed a minimally invasive treatment, based on performance of endoscopic retrograde cholangiopancreatography (ERCP) combined with endoscopic sphincterotomy (ES) and then of laparoscopic cholecystectomy (LC). RESULTS: ERCP was attempted in emergency in 40/57 cases and successfully done in 34 cases. An ES was performed in all but two cases. In 51 patients we performed LC. The overall morbidity was 8. 9% with no mortality. CONCLUSIONS: In the case of ABP early treatment can achieve the restoration of patency of the papilla, reducing the risk of associated cholangitis and the development of pancreatic necrosis. The cholecystectomy prevents the risk of relapse of ABP.

Glucose phosphate isomerase deficiency: biochemical and molecular genetic studies on the enzyme variants of two patients with severe haemolytic anaemia.

UNLABELLED: Biochemical and molecular genetic studies were performed on the enzyme variants of two patients compound heterozygous for glucose phosphate isomerase (GPI) deficiency, both suffering from severe haemolytic anaemia. The enzymes of case 1 (GPI 'Zwickau') and case 2 (GPI 'Nordhorn' [25]), revealed reduced GPI activity and remarkable thermolability. Glucose-6-phosphate (Gluc-6-P) concentration was elevated 2.3 times in case 1 and 3.8 times in case 2. Sequencing the patients' GPI genes showed four different point mutations, two of them involving highly conserved amino acids. The c1039 C-->T substitution, found in the gene of GPI 'Zwickau', has been described recently [30] and causes an Arg 347-->Cys substitution close to the putative catalytic site. The second mutation in this case is a novel c1538 G-->A substitution causing a Trp-->stop mutation at position 513 apparently resulting in premature RNA degradation thus resulting either in a complete lack of protein or a protein which does not show GPI activity. In the gene of GPI 'Nordhorn' a c1028 A-->G mutation was discovered, also previously described [1, 9] causing a Gln 343-->Trp substitution. The second mutation was a novel splice site mutation at the border of intron 15 to exon 16: IVS15-(-2) A-->C which leads to an aberrant splicing of exon 16, thus resulting either in a truncated and most likely inactive enzyme or in no protein at all. CONCLUSION: Biochemical and molecular genetic studies performed with the enzyme variants GPI 'Zwickau' and GPI 'Nordhorn' showed that in both cases the simultaneous occurrence of a single amino acid substitution affecting the active site, together with a nonsense mutation leading to the loss of major parts of the enzyme probably explains the severe clinical course of the disease.

Partially Molten Middle Crust Beneath Southern Tibet: Synthesis of Project INDEPTH Results

INDEPTH geophysical and geological observations imply that a partially molten midcrustal layer exists beneath southern Tibet. This partially molten layer has been produced by crustal thickening and behaves as a fluid on the time scale of Himalayan deformation. It is confined on the south by the structurally imbricated Indian crust underlying the Tethyan and High Himalaya and is underlain, apparently, by a stiff Indian mantle lid. The results suggest that during Neogene time the underthrusting Indian crust has acted as a plunger, displacing the molten middle crust to the north while at the same time contributing to this layer by melting and ductile flow. Viewed broadly, the Neogene evolution of the Himalaya is essentially a record of the southward extrusion of the partially molten middle crust underlying southern Tibet.