An automatic tracking system for phase-noise measurement

A low cost, automatic tracking system for phase noise measurement has been implemented successfully. The tracking system is accomplished by applying a charge pump phase-locked loop as an external reference source to a digital spectrum analyzer. Measurement of a 2.5 GHz, free-running, voltage-controlled oscillator demonstrated the tracking accuracy, thus verifying the feasibility of the system.     

Pattern recognition techniques for automatic detection of suspicious-looking anomalies in mammograms

We have employed two pattern recognition methods used commonly for face recognition in order to analyse digital mammograms. The methods are based on novel classification schemes, the AdaBoost and the support vector machines (SVM). A number of tests have been carried out to evaluate the accuracy of these two algorithms under different circumstances. Results for the AdaBoost classifier method are promising, especially for classifying mass-type lesions. In the best case the algorithm achieved accuracy of 76% for all lesion types and 90% for masses only. The SVM based algorithm did not perform as well. In order to achieve a higher accuracy for this method, we should choose image features that are better suited for analysing digital mammograms than the currently used ones.     

Possible mechanism for drug retardation from glyceryl monostearate matrix system

Lipophilicity was evaluated as a possible mechanism for drug retardation from a glyceryl monostearate matrix system. Lipophilicity of the glyceryl monostearate matrix system was studied using contact angle measurement of water droplets on the surface of compressed disks, extrudate ascension of water, and movement of water through a powder mixture packed in a high-performance liquid chromatographic (HPLC) column. Increase in glyceryl monostearate content resulted in an increase in water droplet contact angle, decrease in the rate of water ascending the extrudate, and increase in the pressure values as a function of flow rate of water moving through the powder mixture. These could be due to the increase in lipophilicity of the matrix, rendering the matrix less wettable. As a result, the rate of water penetration into the matrix decreased, and the drug release could be sustained.     

Determination of cell origin after marrow transplantation in canines by polymerase chain reaction and quantitation of the ZFY/ZFX genes

BACKGROUND: In order to follow the course of bone marrow engraftment in dogs, and to determine the presence, and percentage, of donor-derived cells in other canine tissues, a simple and fast method of determining cell origin after sex-mismatched bone marrow transplantation was developed. METHODS: Using universal primers, fragments from genomic DNA corresponding to ZFX and ZFY genes were amplified by polymerase chain reaction. A restriction fragment length polymorphism, combined with densitometric analysis, was then used to distinguish and quantitate ZFY and ZFX sequences. Unknown samples were analyzed against standards of known mixtures of male and female DNA. RESULTS: Canine ZFY and ZFX genes were clearly resolved after amplification, digestion with HaeIII, and denaturing polyacrylamide gel electrophoresis. Microchimerism could be detected in male and female dog DNA samples derived from a range of fresh and frozen tissues including spleen, testicle, and the central nervous system. The levels of chimerism determined using this method were in either agreement with results obtained by karyotyping or more sensitive, with a detection limit of 0.4% compared with 1-2%. CONCLUSIONS: Polymerase chain reaction/restriction fragment length polymorphism detection of the ZFY and ZFX genes was found to be simple, accurate, and reliable for assessing engraftment in dogs. When compared with cytogenetic analysis, this method was found to be faster to perform, more capable of detecting lower levels of microchimerism, and useful for detecting donor-derived cells in stored specimens and in tissues other than peripheral blood or bone marrow.     

Spontaneous aortocaval fistula secondary to ruptured abdominal aortic aneurysm

Twenty-nine patients referred consecutively to a cancer clinic because of recurrent metastatic malignant melanoma were given 5 mg of Connaught Laboratories bacillus Calmette-Guérin (BCG) by multiple cutaneous puncture at weekly and later at monthly intervals. Eight were also treated with autologous tumour vaccine and three with intralesional BCG. This group was compared with a retrospective control group of 54 patients treated with surgery and radiotherapy alone after recurrence. Prognostic features such as site of primary and of first metastasis, disease-free interval, age and sex were similar in the two groups. However, the median survival from the time of first recurrence was 12 months in the control group but 21 months in the BCG-treated group. The major improvement was in patients with disease limited to the regional lymph nodes: the median survival was 16 months in the control group but over 32 months in the BCG-treated group. Autologous tumour vaccine appeared to have no effect on survival. Serial testing of immunocompetence did not offer any prognostic advantage, although the results of some tests correleated well with extent of disease.     

Primary plasmalemmal carnitine transporter defect manifested with dicarboxylic aciduria and impaired fatty acid oxidation

Respiratory syncytial virus (RSV), a common cause of both upper and lower respiratory tract infection (LRTI) in infants and children, is rarely described as an infective agent in adults. It has been reported in bone marrow transplant (BMT) recipients and patients with malignancy immunosuppressed by chemotherapy. Such reports are often associated with a high mortality. We report an outbreak of RSV infection which occurred predominantly in BMT recipients in which early investigation and institution of ribavirin therapy resulted in all patients making a full recovery.     

Ventilating tubes in tympanoplasty

The successful surgical treatment of chronic otitis media or its sequela is frequently related to a ventilated tympanic cavity. Tubes at tympanoplasty have been recommended to assure ventilation until eustachian tube and middle ear mucosal functions have been restored and to prevent the complications of graft loss, atelectasis, cholesteatoma and ossicular destruction. This presentation reviews the literature on the subject and documents our results in 40 patients treated by tympanomastoid surgery with ventilating tubes. The types of tubes used, the surgical technique involved, and the selection of cases suitable for this method are described. Cholesteatoma was the primary disease in 32 patients, 6 had chronic otitis media, 1 cholesterol granuloma, and 1 eosinophilic granuloma. Complete healing of grafts following extrusion or removal of the tubes occurred in 34 patients, 2 tubes remain in place, 3 patients had persistent tube site perforations, and 1 was lost to follow-up. None of the patients had graft breakdown as a result of tube placement, and there has been no recurrence of cholesteatoma. In all cases, the follow-up period is a minimum of 18 months and extends to 92 months.     

Studies on the hydrogen belts of membranes: I. Diester, diether, and dialkyl phosphatidycholines and polyoxyethylene glycerides in monolayers with cholesterol

The hydrogen belts of membranes are defined as the regions consisting of hydrogen bond acceptors, i.e., the C=O groups of glycero- and sphingolipids, and hydrogen bond donors, i.e., cholesterol-OH, sphingolipid-OH, proteins, and water. Lipid-lipid hydrogen bonding in these belts has been suggested. The connection of such hypothetical bonding with the condensation effect, i.e., the apparent reduction of surface area occupied by phospholipids in mixed monolayers with cholesterol, has been tested with lipids possissing and lacking C=O groups: diester, diether, and dialkyl phosphatidylcholine, and analogous polyoxyethylene diglycerides. Condensation by cholesterol was observed for all lipids. Consequently, the hypothetical lipid-C=O-cholesterol hydrogen bonding is not a prerequisite for the condensation effect.     

Megaesophagus and pneumonia associated with Mycobacterium chelonei. A case report and a literature review

The case of a 37-year-old woman who developed a subacute, bilateral, noncavitary pneumonia 5 years after a colon interposition esophagoplasty is presented. Mycobacterium chelonei, subspecies abscessus, was assigned a pathogenic role based on the findings of (1) a clinical and roentgenographic picture consistent with tuberculosis, (2) sputum smears showing acid-fast bacilli, (3) repeated sputum cultures yielding heavy growths of Mycobacterium chelonei, subspecies abscessus, and (4) a 12-mm by 12 mm-skin test response to homologous antigen (purified protein derivative-CL) with no response to an equivalent dose of purified protein derivative-S. The patient recovered fully without significant antituberculous chemotherapy. A survey of the literature revealed 11 similar case reports featuring a documented association between megaesophagus and pulmonary infection with rapidly growing mycobacteria.