Classification and knowledge discovery in protein databases

We consider the problem of classification in noisy, high-dimensional, and class-imbalanced protein datasets. In order to design a complete classification system, we use a three-stage machine learning framework consisting of a feature selection stage, a method addressing noise and class-imbalance, and a method for combining biologically related tasks through a prior-knowledge based clustering. In the first stage, we employ Fisher's permutation test as a feature selection filter. Comparisons with the alternative criteria show that it may be favorable for typical protein datasets. In the second stage, noise and class imbalance are addressed by using minority class over-sampling, majority class under-sampling, and ensemble learning. The performance of logistic regression models, decision trees, and neural networks is systematically evaluated. The experimental results show that in many cases ensembles of logistic regression classifiers may outperform more expressive models due to their robustness to noise and low sample density in a high-dimensional feature space. However, ensembles of neural networks may be the best solution for large datasets. In the third stage, we use prior knowledge to partition unlabeled data such that the class distributions among non-overlapping clusters significantly differ. In our experiments, training classifiers specialized to the class distributions of each cluster resulted in a further decrease in classification error.     

Effect of short-term Psychiatric Intervention in Cancer Patients

A total of 50 patients undergoing cancer treatment at Malignant Disease Treatment Centre were included in the present study aimed at evaluating the psychological status of cancer patients. All patients filled a specially designed proforma and the following psychological questionnaires : General Health Questionnaire, Carroll Rating Scale for Depression, State-Trait Anxiety Inventory, PGI General Well-being Scale and Quality of Life Scale. Analysis of the results showed that 22 (44%) of the cancer patients had psychiatric disorders and this number had reduced to 12 (24%) after therapy. The difference was statistically significant. Psychiatric treatment also resulted in a statistically significant reduction in level of depression as measured by Carroll Rating Scale for depression. Short term psychiatric treatment was found to be very useful in treating psychiatric morbidity and depression in cancer patients.Key Words: Cancer, Depression, Psychiatric morbidity     

Plasma serotonin and histamine levels in hemodialysis-related pruritus are not significantly influenced by 5-HT3 receptor blocker and antihistaminic therapy

BACKGROUND: Elevated plasma histamine levels are considered to play a part in the pathophysiology of hemodialysis-related pruritus. However, antihistaminic therapy often fails to provide sufficient relief. Elevated serotonin levels in patients on dialysis therapy have also been described but the effects of 5-HT3 receptor antagonists on hemodialysis-related pruritus remain controversial. METHODS: we conducted a study to determine plasma histamine and serotonin levels before and after treatment with 5-HT3 receptor antagonists (tropisetron 5 mg and ondansetron 8 mg) and an antihistamine (cetirizine 10 mg). Eleven hemodialysis patients with a history of pruritus participated in this study,10 healthy volunteers served as control group. RESULTS: Histamine and serotonin values were normal in patients and controls. Treatment with cetirizine did not significantly reduce histamine levels in patients or in controls. Tropisetron and ondansetron likewise did not alter serotonin levels in patients. Tropisetron treatment did not significantly change serotonin levels in controls. CONCLUSION: Histamine and serotonin are no major mediators of pruritus in hemodialysis patients. Elevated histamine levels are occassionally seen and may be due to the increased mast cell number found in a subgroup of hemodialysis patients. Our findings explain the only marginal relief of antihistamines and the controversial antipruritic effect of serotonin receptor antagonists in hemodialysis-related pruritus.     

An outbreak of food poisoning in a military establishment

Background: An outbreak of food poisoning in a military establishment mess was investigated and remedial measures suggested.     

TRACHEOSTOMY COMPLICATIONS AND THEIR MANAGEMENT

The word tracheostomy derived from two greek words meaning ‘I cut the trachea’ has been known for about 3500 yrs. The process has evolved over the years and has undergone revolutionary changes in the methodology, instrumentation and indications. Although tracheostomy is now commonly used the complication rate remains high. In our series it was 48% which is comparable with other series. The purpose of this paper is to discuss the complications of tracheostomy with special attention to their management and prevention.KEY WORDS: Complications, Tracheostomy     

Management of nucleus and IOL drop

Background: Thirty six cases of lenticular nucleus drop following phacoemulsification and 43 cases of posterior dislocation of intraocular lens (IOL) inclusive of two paediatric cases were managed by a modified vitrectomy procedure without using perfluorocarbon liquid (PFCL).     

SPA: Short peptide analyzer of intrinsic disorder status of short peptides

Disorder prediction for short peptides is important and difficult. All modern predictors have to be optimized on a preselected dataset prior to prediction. In the succeeding prediction process, the predictor works on a query sequence or its short segment. For implementing the prediction smoothly and obtaining sound prediction results, a specific length of the sequence or segment is usually required. The need of the preselected dataset in the optimization process and the length limitation in the prediction process restrict predictors’ performance. To minimize the influence of these limitations, we developed a method for the prediction of intrinsic disorder in short peptides based on large dataset sampling and statistics. As evident from the data analysis, this method provides more reliable prediction of the intrinsic disorder status of short peptides.     

Functioning oncocytic adenoma of the pituitary

A case of a functioning invasive pituitary oncocytoma in a 50-year-old man is reported. The serum prolactin was increased and immunocytochemical staining was positive for prolactin. In addition to numerous mitochondria within the neoplastic cells, structurally abnormal mitochondria with crystalline inclusions were also present. Another interesting feature was the presence of about 10 to 15% of non-oncocytic cells which showed prominent RER and Golgi apparatus as found in functioning pituitary adenomas. It is likely that these secretorily active cells were responsible for the functional activity of the tumour.