Clinical experience in temporomandibular joint arthroscopy

Clinical experience of arthroscopy in 12 temporomandibular joints with a clinical diagnosis of closed lock was described. There were 10 patients and all were females with a mean age of 31.2 years (range 20 to 59 years). The antero-lateral approach was used for entry into 11 joints. The clinical findings were adhesions (64%), fibrillation (64%), anterior displacement of disc (36%) and scuffing of the articular surface of the glenoid fossa (9%). Two of the joints that had arthrocentesis prior to arthroscopy did not show any different findings from the rest. Of the 8 patients who had pre-arthroscopy pain, 7 patients (88%) had reduction of the symptom. Three patients (38%) had complete resolution of pain. The range of mouth opening (measured as maximal incisor opening) increased in all patients two weeks following arthroscopy. The average change in maximal incisor opening was 40.3% with a range of 22% to 85%. The mean follow-up was 34 months (range 4 to 68 months).     

Validation of [13C]urea breath test for Helicobacter pylori using a simple gas chromatograph-mass selective detector

OBJECTIVE: Isotope ratio mass spectrometry (IRMS) is the accepted method for accurately measuring the 13CO2:12CO2 ratio in the non-invasive and non-radioactive [13C]urea breath test (13C-UBT) for Helicobactor pylori. The IRMS instrument, an expensive and highly specialized analyser, is rarely available. The objective of this project was to modify and validate the use of a simple bench-top gas chromatograph-mass selective detector (GC-MSD) for 13C-UBT. METHODS: Breath samples from 71 patients were taken at baseline and 30 min after ingestion of 100 mg [13C]urea. The breath samples were analysed using GC-MSD in the selected ion monitoring mode. The reference 13CO2:12CO2 ratio was from NBS19 obtained from the US National Institute of Standards and Technology. 13CO2:12CO2 ratios of the breath samples were determined. Excess delta per thousand (per mil, delta/thousand) of the 30 min sample over the baseline (deltadelta/thousand) of > or = 6deltadelta/thousand was considered H. pylori positive. Results from 13C-UBT and histology determined blind to each other were compared. RESULTS: The coefficient of variation of the reference 13CO2:12CO2 ratio was 0.06%. Using histology as the 'gold standard', the sensitivity (97.9%) and specificity (95.8%) of the GC-MSD 13C-UBT were comparable to those of other methods of H. pylori diagnosis. CONCLUSION: A gas chromatograph coupled to a mass selective detector that is available in many analytical and biomedical laboratories can be used for the 13C-UBT. This method will increase the availability and reduce the cost of this non-invasive, non-radioactive diagnostic test.     

Emergency postcoital contraception

Pancreatitis may be acute or chronic, mild or severe. Acute necrotizing pancreatitis remains the most serious form of acute pancreatitis and accounts for the majority of complications. Although there is an established nomenclature for pancreatitis and pancreatic fluid collections, such as pancreatic pseudocysts, it is not widely understood or recognized by gastroenterologists. Because the management options for the treatment of pancreatic fluid collections continues to evolve with an increased use of endoscopic therapy, gastroenterologists will be increasingly called on to treat patients with pancreatitis and its complications. This article addresses and summarizes pancreatic fluid collections and their management, with an emphasis on endoscopic drainage.     

Two-year follow-up of directly-observed intermittent regimens for smear-positive pulmonary tuberculosis in China

SETTING: The tuberculosis component of the Infectious and Endemic Disease Control Project in the People's Republic of China is the largest single tuberculosis control project in the world using directly-observed therapy and standardized intermittent regimens. OBJECTIVE: To determine the two-year relapse and mortality rates following completion of treatment. DESIGN: A prospective cohort study of 649 cases cured in this project. The 306 new and 343 retreatment cases were treated under field conditions with 2H3R3Z3S3/4H3R3 and 2H3R3Z3E3S3/6H3R3E3, respectively. Following treatment completion, two sputum samples were collected every six months for two years and examined for acid-fast bacilli. Causes of death were identified. RESULTS: The two-year relapse rates for new and retreatment cases were 3.3% and 5.6%, respectively. Retreatment cases with delayed sputum conversion had a greater risk for subsequent relapse. The two-year mortality rate for new and retreatment cases was 3.3% and 8.5%, respectively. The higher mortality rate in retreatment cases was not attributable to relapse of disease, but rather to non-infectious sequelae of tuberculosis. CONCLUSION: The use of directly-observed intermittent regimens is effective in permanently removing infectious tuberculosis cases from the community.     

hSK4, a member of a novel subfamily of calcium-activated potassium channels

The gene for hSK4, a novel human small conductance calcium-activated potassium channel, or SK channel, has been identified and expressed in Chinese hamster ovary cells. In physiological saline hSK4 generates a conductance of approximately 12 pS, a value in close agreement with that of other cloned SK channels. Like other members of this family, the polypeptide encoded by hSK4 contains a previously unnoted leucine zipper-like domain in its C terminus of unknown function. hSK4 appears unique, however, in its very high affinity for Ca2+ (EC50 of 95 nM) and its predominant expression in nonexcitable tissues of adult animals. Together with the relatively low homology of hSK4 to other SK channel polypeptides (approximately 40% identical), these data suggest that hSK4 belongs to a novel subfamily of SK channels.     

Alveolar permeability enhancement by oleic acid and related fatty acids: evidence for a calcium-dependent mechanism

Pulmonary exposure to oleic acid (OA) is associated with permeability alterations and cellular damage; however, the exact relationship between these two effects has not been clearly established. Using cultured alveolar epithelial monolayers, we demonstrated that OA and some other fatty acids (< or = 50 microM) can induce permeability changes without detectable cellular damage. At higher concentrations, however, OA caused severe membrane damage and leakage to solute flux. The permeability enhancing effect of OA was observed with both the paracellular marker 3H-mannitol and the lipophilic transcellular indicator 14C-progesterone. While the effect of OA on transcellular permeability may be attributed to its known effect on membrane fluidity, the paracellular promoting effect of OA and its mechanism are not well established. We postulated that OA may increase paracellular permeability through a Ca(2+)-dependent tight junction mechanism. Using dual-excitation fluorescence microscopy, we demonstrated that OA can increase intracellular calcium, [Ca2+]i, in a dose-dependent manner. This effect was transient at low OA concentrations (< or = 50 microM) but became more pronounced and sustained at higher concentrations. Free hydroxyl and unsaturated groups were required for this activation since esterified OA (oleic methyl ester) and stearic acid (a saturated fatty acid with equal chain length) had much reduced effects on both the [Ca2+]i and the permeability alterations. Degree of unsaturation was unimportant since linolenic acid (18:3), linoleic acid (18:2), and OA (18:1) had similar and comparable effects on the two parameters.(ABSTRACT TRUNCATED AT 250 WORDS)