Muscle necrosis in the extremities: evaluation with Tc-99m pyrophosphate scanning--a retrospective review

A retrospective review was done of 34 extremities studied between 1981 and 1985 with technetium-99m pyrophosphate scanning; 22 were subsequently amputated. Results of detailed pathologic examination or immediate postoperative examination of the resected extremity were available in 16 cases. In these cases, scanning had allowed correct prediction of the level of amputation and of the specific areas of muscle infarction in 13 cases. In the one case in which amputation was performed for infection rather than muscle necrosis, the lack of necrosis was correctly predicted with the scan. The limited results of this study indicate that the Tc-99m pyrophosphate scan allows the location of necrotic muscle to be predicted accurately and may therefore be a useful adjunct in determining the best level for ultimate amputation. Special caution is required in those cases in which muscle necrosis is due to acute causes (e.g., traumatic thrombosis) rather than chronic vascular disease.     

Response to neoadjuvant chemotherapy and effects of tumor regression in gastric cancer

AIMS: Aim of this study is the evaluation of the effects induced by neoadjuvant chemotherapy (NACT) and its impact on survival on a series of locally advanced gastric carcinomas. METHODS: Downstaging was assessed comparing pre-treatment clinical and laparoscopic staging with post-operative pathologic staging on 30 consecutive patients who completed a 3-year follow-up. Tumor downstaging and the grade of pathologic response were included in a statistical correlation between tumor regression induced by NACT and 3-year survival. RESULTS: In this series tumor downstaging was obtained in 13 out of 30 patients. After the completion of 3-year follow-up, overall survival was >37.5months with an overall survival rate of 56.7%; this figure reached up to 70.8% in those cases who benefited from a R0-resection (24/30 patients: R0-resection rate 80.0%). CONCLUSIONS: In this study the 3-year survival for locally advanced gastric cancer treated by NACT prior to "D2" surgical resection, compares favourably with historical series treated by surgery alone. Patients who obtained T-downstaging and subsequently benefited from a R0-resection had a definitely better chance of cure, according to a complete 3-year follow-up.     

Pulse sequence optimization for MR imaging using a paramagnetic hepatobiliary contrast agent

Paramagnetic agents enhance contrast between tissues in magnetic resonance (MR) imaging by altering tissue relaxation times. The effect of these changes on MR image intensity depends in part on the choice of operator-controlled pulse sequence parameters. With the newly described paramagnetic hepatobiliary contrast agent, iron(III) ethylenebis-(2-hydroxyphenylglycine), Fe(EHPG)-, an in vivo experimental analysis of pulse sequence optimization was performed on the rat. We compared the enhancement of the liver divided by background noise, EL/N, of standard inversion-recovery (IR) and spin-echo (SE) T1-weighted pulse sequences and several pulse sequences theoretically predicted to have improved EL/N. Optimization of the echo time (TE = TEmin) gave a substantial (greater than 60%) increase in EL/N over the standard IR and SE pulse sequences. Images obtained with optimized repetition rate and inversion time gave only a slight additional improvement. Within the uncertainties of our relaxation measurements, the measured changes in EL/N with pulse sequence optimization corresponded well with theoretical predictions. With the experimental and theoretical data, the importance of using a short echo time to obtain maximal T1 contrast in contrast-enhanced MR imaging and the relative merits of optimized SE versus IR pulse sequences for contrast-enhanced MR imaging are discussed.     

Fluorocontaining D-cycloserines. Synthesis and in vitro evaluation of antimicrobial and antiviral activities.

Some fluoroacylderivatives at the side chain NH2 of D-cycloserine were synthesized and evaluated in vitro for antimicrobial activity against bacteria and tubercular or non-tubercular mycobacteria. Against the used Gram-positive and Gram-negative strains only trifluoroacetamide 1 exhibited comparable MIC values and lower MBC values than those of parent antibiotic. Other fluoroacycloserines, inactive at all on these bacteria, were found to inhibit the growth of mycobacteria when tested in liquid media. The in vitro anti-Herpex Simplex virus type-2 (HSV-2) activity was also investigated on HEp-2 and Vero cells. The obtained results demonstrated an antiviral activity of the compounds 1 and 3 when tested on Vero cell-lines, whereas the same cycloserine is inactive.     

N-substituted p-fluorobenzencarboxyamides. Evaluation of the in vitro antimicrobial activity

As part of our investigations on fluorine containing compounds of potential pharmacological interest, a series of N-substituted p-fluorobenzencarboxyamides, analogs of previously studied p-fluorobenzensolfonamides, was prepared. The in vitro antibacterial and antimycotic properties were also assayed. The replacement of the sulfonamide group with an isosteric carboxyamide one, was found to confer to trifluoromethylsubstituted compounds good activity against some strains of yeasts (Candida) and hyphomycetes (Tricophyton, Aspergillus, Microsporum, Epidermophyton). These compounds however are not very active against the gram-positive and gram-negative bacteria on which the corresponding sulfonanilides showed significant activity.     

Management of skeletal giant cell tumors of the phalanges of the hand

Five cases of unicentric benign giant cell tumors of the phalanges of the hand are reported. Three patients were initially treated with curettage and bone grafting; two had recurrences that necessitated ray resection as the definitive treatment, and one was free of disease at 16 years' follow-up. The two patients who were primarily treated with ray resection were free of disease at follow-up of 2 and 1 years, respectively. Enneking's surgical staging system and Lodwick's x-ray grading of bone tumors were used to evaluate management methods.     

Multiphasic MR imaging: a new method for direct imaging of pulsatile CSF flow

A new technique is described that allows for the creation of pure pulsatile flow magnetic resonance (MR) images in a single acquisition. Five to 16 electrocardiographically gated images spanning the entire cardiac cycle are obtained with use of a gradient-echo pulse sequence. The section can be varied from 4 mm thick to full thickness projection. Taken singly, each image provides direct assessment of flow direction and velocity. Subtraction of image pairs eliminates signal detected from stationary protons, producing images of pulsatile flow. In this study the technique was used to image the flow of cerebrospinal fluid (CSF) in healthy subjects and in one patient with syringohydromyelia. The data suggest that multiphasic MR imaging provides a powerful means for the noninvasive assessment of CSF pulsatile flow dynamics and may have potential clinical application for the investigation of a variety of abnormalities such as normal pressure hydrocephalus, syrinx, and spinal block.     

3,3'-bi-1,3-thiazolidine]-4,4'-dione system. III. Evaluation of the antimicrobial and antitumor properties of 2,2'-disubstituted derivatives and their 1,1'-disulfones

A series of dl and meso 2,2'-disubstituted-[3,3'-bis-1,3-thiazolidine]-4,4'-diones and their 1,1'-disulfone derivatives have been tested for their antimicrobial activity against gram-positive, gram-negative and Candida strains and for antitumor activity against leukemic P.388 tumor system in mice. None of the tested bi-thiazolidinones showed any significant antitumor properties; only few 1,1'-disulfones exhibited some antibacterial activity.     

Rickettsia rickettsii infection of cultured human endothelial cells induces tissue factor expression

Microvascular thrombi underlie many of the clinical manifestations of Rocky Mountain spotted fever (RMSF), a disease characterized by Rickettsia rickettsii infection of vascular endothelial cells. Studies were designed to determine whether R rickettsii-infection of cultured human umbilical vein endothelial cells results in tissue factor (TF) induction, a process that could directly activate coagulation in infected vessels. Whereas uninfected endothelial cell cultures showed essentially undetectable TF mRNA and activity, both TF mRNA and activity were present after R rickettsii infection. TF mRNA levels were transient, peaking at 4 hours after the initiation of infection, whereas the peak of TF activity occurred at 8 hours. Induction of the TF response requires the intracellular presence of R rickettsii organisms, because uninfected rickettsia were ineffective and the response was blocked by inhibiting rickettsial entry using cytochalasin B. TF induction was not mediated by endothelial cell release of soluble factor, because no response was induced using culture medium conditioned by R rickettsii-infected cells. Furthermore, preadsorption of suspensions of R rickettsii with polymyxin B to remove contaminating lipopolysaccharide did not eliminate the TF response. Induction of TF in vital endothelial cells during R rickettsii infection could be the trigger for vascular thrombus formation of RMSF.     

Halogenated isoniazid derivatives as possible antitubercular and antineoplastic agents. Note 1.

Halogenated arylhydrazones, 2-aryl-4-thiazolidinones and their 1,1-dioxides containing isoniazid (INI) moieties were prepared and explored for antimicrobial (against bacteria, Candida and mycobacteria) and antitumor activities. None of the tested compounds showed any marked antimicrobial effect. Furthermore, among the compounds submitted to NCI in vitro primary antitumor screening, those bearing 3-fluoro or -chlorophenyl substituents were found to possess selective inhibitory effects on the growth of non small cell lung cancer, whereas those with para-phenyl substituents displayed selective effects, sometimes statistically significant, against leukemias.