CT of appendicitis in children

PURPOSE: Our goal was to review the CT findings and to help define the role of CT in the evaluation of appendicitis in children. METHOD: Of 730 children with surgically proven appendicitis, 22 underwent preoperative CT evaluation. Their CT scans and operative and pathology records were retrospectively reviewed. The CT scans were evaluated for appendiceal wall thickness, diameter, and location, appendicoliths, pericecal inflammation, phlegmon, abscess, free fluid, small bowel dilatation, and bowel wall thickening. Criteria for diagnosing appendicitis were (a) appendiceal wall thickening (> 1 mm) or (b) presence of abscess, phlegmon, or pericecal inflammation associated with appendicolith(s). Prospective reports of ultrasound examinations performed within 2 days of the CT scans were available in 14 children and were correlated with the CT findings. RESULTS: An abnormally thickened appendix, with a diameter ranging from 9 to 18 mm, was seen in four children. Three appendices were retrocecal and one was near the cecal tip, anterior to the iliac vessels. Appendicoliths were present in 10 children, multiple in 1. Abscesses were seen in 13 of 22 children, multiple in 5. Phlegmon was seen in five children and pericecal inflammation in two. Bowel wall thickening was present in seven children and small bowel dilatation was noted in six. Other findings included free fluid, hydronephrosis, thickening of urinary bladder wall, air in the uterus and vagina, adenopathy, and thickening of the abdominal wall musculature. CT was diagnostic of appendicitis in 11 of 22 children (50%). In 14 children with both ultrasound and CT studies, CT was slightly better in diagnosing appendicitis and visualizing the abnormal appendix and was superior in defining the presence and extent of abscess and inflammation in 9 of 14 children. CONCLUSION: CT is a useful adjunct in diagnosing appendicitis in children, with a major role in cases of complicated appendicitis.     

Effect of preparation technique on the properties of Mo-containing Al-MCM-41

The Al-MCM-41 has been used as support to prepare Mo-containing catalysts. The 12- molybdophosphoric heteropoly acid (HPMo) is used as initial compound. The catalysts are synthesized by two different methods: incipient impregnation with aqueous solution of the acid and mechanochemical synthesis. The samples were tested in the reaction of the thiophene hydrodesulfurization after activation with mixture H₂ + H₂S. The effect of the preparation method of the catalysts on their physicochemical and catalytic properties has been studied. A partial destruction of the loaded compound is observed in mechanochemically treated sample whereas the aggregates are formed from the particles of different size in the impregnated sample. The specific surface area of the sample prepared by mechanical–chemical treatment decreases 2–3 times, while the total pore volume is about four times lower. The HDS activity is higher on the impregnated sample than on the mechanochemically treated one.     

Antimicrobial and immunological activity of ethanol extracts and fractions from Isopyrum thalictroides

The antimicrobial and immunological properties of ethanol extracts, non-alkaloid, tertiary alkaloid and quaternary alkaloid fractions, obtained from roots and aerial parts of Isopyrum thalictroides were examined. The non-alkaloid fraction from aerial parts inhibited the growth of seven test microorganisms and was the most effective suppressor of classical pathway (CP) complement activity in normal human serum (NHS) and guinea pig serum (GPS). The alkaloid fractions, containing quaternary alkaloids expressed suppressive effect on mitogen-induced splenocyte proliferation. The in vitro antibody response against sheep red blood cells (anti-SRBC) was inhibited by ethanol extracts and quaternary alkaloid fraction. The intraperitoneal (i.p.) application of ethanol extract and tertiary alkaloid fraction from aerial parts showed that they possess in vivo effect on alternative pathway (AP) complement activity, anti-SRBC response and delayed type hypersensitivity (DTH).     

Antibacterial activity of calcium hydroxide-containing endodontic sealers on Enterococcus faecalis in vitro

Nickel-titanium instruments purportedly resist deformation and loss of sharpness better than do stainless steel instruments but may be more susceptible to breakage. The processes of wear and breakage of nickel-titanium and stainless steel instruments were examined. Sixty files of five types (12 each) and three manufacturers were used. All were used repeatedly in curved canals until failure or for a maximum of 22 minutes. Each instrument was examined with scanning electron microscopy both new (control) and at spaced intervals for evidence of wear and fatigue. All new instruments were of good quality. Stainless steel instrument tended to wear the most rapidly, and next were nickel-titanium rotary instruments; the most resistant to wear were nickel-titanium hand instruments. There were few instrument separations. In general, nickel-titanium (particularly hand) instruments resisted deterioration better than did stainless steel. Nickel-titanium rotary instruments (2 of 12) had the most breakage.