Mycobacterium mimicking metastatic melanoma.

We present three patients with lung nodules with an antecedent history of primary cutaneous melanoma or metastasis of melanoma to extrathoracic lymph nodes. Based on radiological findings, it was suspected that these patients had metastatic disease. Subsequent investigations confirmed the cause of the nodules was non-tuberculous mycobacterial infection. We discuss the similarities in symptoms and radiological features between atypical mycobacterial infections and metastatic disease and why a biopsy is important prior to planning a patient's treatment.

Joining the DOTS in Bali: private practitioners' perceptions of tuberculosis control.

SETTING: The Indonesian island of Bali has both a national public tuberculosis (TB) programme and a significant private sector that provides treatment for patients with TB. OBJECTIVE: To explore private practitioners' perceptions of barriers to the treatment of patients with TB in Bali to inform strategies for future programme development. DESIGN: Semi-structured interviews were conducted with private practitioners who treated TB patients in their private practice. RESULTS: The main barriers to improved TB control in Bali identified by private practitioners reflect difficulties encountered within the following four areas: patient nonadherence to treatment, limitations of public services, public-private integration and limitations of private services. Private practitioners identified the need for improvements in the level of community education regarding TB, the degree of public-private interaction, the quality of diagnostic services and practitioner access to training. CONCLUSION: This study identified both strengths and weaknesses for TB control in the private sector, as well as considerable variations in perceptions and practice among private practitioners. The development of strategies to address these difficulties and utilise the inherent strengths of both public and private practitioners will be essential for improved service provision and TB control in Bali.

Molecular structures and interactions of repetitive peptides based on wheat glutenin subunits depend on chain length.

Synthetic and recombinant peptide models of the central repetitive domain of the high molecular weight subunits of wheat glutenin with different numbers of the consensus repeat motifs PGQGQQ + GYYPTSLQQ (21, 45, 110, and 203 residues long) and a recombinant 58,000-Da relative molecular mass (M(r) 58,000) repetitive peptide from a single subunit (1Dx5) are studied using Fourier transform IR spectroscopy. The spectra of the dry peptides are very similar; at low water contents (<76% relative humidity) there is an increase in beta-sheet structures in all peptides. However, on further hydration the content of beta sheets decrease and more beta turns are observed. The changes during the second step of hydration are very marked in the 21 and 45 residue peptides, but they are less apparent in the longer perfect repeat peptides. In the 110 and 203 residue peptides hydration results in increased contents of intermolecular beta-sheets and less beta-turn formation. In contrast, the beta-turn content of the M(r) 58,000 peptide increases during the second hydration step. The decreased extent of structure changes with increasing chain length indicates that cumulative intermolecular interactions, in particular hydrogen bonds, are an important factor in determining the structures in the solid state. The regularity of the perfect repeat sequences in the 21, 45, 110, and 203 residue peptides may favor the formation of larger stretches of intermolecular beta sheets. In contrast, the M(r) 58,000 peptide contains imperfect repeats (in common with native glutenin subunits), which may limit its ability to form intermolecular beta sheets.

Synthesis, expression and characterisation of peptides comprised of perfect repeat motifs based on a wheat seed storage protein.

We have developed a novel method for constructing synthetic genes that encode a series of peptides comprising perfect repeat motifs based on a high molecular weight subunit (HMW glutenin subunit), a highly repetitive storage protein from wheat seed. A series of these genes of sequentially increasing size was produced, four of which (called R3, 4, 5, 6) were expressed in Escherichia coli. Activity of the synthetic genes in E. coli was confirmed by Northern blot analysis but SDS-PAGE of crude protein extracts failed to show any expressed peptides when stained using Coomassie brilliant blue R250. However, Western blots probed with a HMW glutenin subunit-specific polyclonal antibody showed the presence of the R6 peptide (M(r) 22005) in the crude cell extracts and both this and the R3 peptide (M(r) 12005) were subsequently purified by extraction with hot aqueous ethanol followed by precipitation with acetone and separated by RP-HPLC. The R4 and R5 peptides were not purified. The purified R3 and R6 peptides absorbed Coomassie brilliant blue R250 or other protein stains only weakly and this was considered to account for their failure to be revealed by staining of separations of the crude protein extracts. Circular dichroism spectroscopy showed that both peptides had similar beta-turn rich structures similar to the repetitive sequences present in the whole HMW glutenin subunits. We conclude that expression of perfect repeat peptides in E. coli is a suitable system for the study of structure-function relationships in wheat gluten proteins and other highly repetitive proteins.

A comparison of the personality profiles of internal medicine residents, physician role models, and the general population.

PURPOSE: To compare personality profiles of internal medicine residents with those of the general population and positive role models in medicine. METHOD: A widely used personality inventory, NEO PI-R, which measures five major personality factors and 30 important personality facets, was administered in 1998 to 104 physicians in internal medicine residency and earlier to a nationwide sample of 188 physicians selected as positive role models in medicine. RESULTS: The internal medicine residents, compared with the general population, were more likely to be attentive, to have deeper intellectual curiosity, to have higher aspiration levels, to have more vivid imaginations, to be more receptive to their emotions, to be interested in mental stimulation, and to think carefully before acting. The residents, compared with role models in medicine, were less eager to face challenges, less able to control their impulses, less able to cope with adversity, less easygoing, and less relaxed, but were more likely to crave excitement. CONCLUSION: Internal medicine residents and positive role models in medicine have some distinct personal qualities. Understanding the qualities of successful physicians can be helpful in career counseling of medical students and young physicians.

Fear of AIDS among clinical laboratory scientists: a follow-up survey.

OBJECTIVE: To compare attitudes and behaviors about acquired immunodeficiency syndrome (AIDS) of clinical laboratory scientists (CLSs) who are considering leaving the profession with those of CLSs planning to stay in the profession. DESIGN: Survey of a convenience sample of conference attendees. SETTING: Annual meetings of the New Jersey Society for Medical Technologists held April 4-5, 1990, in Woodbridge, New Jersey, and April 9-10, 1988, in Asbury Park, New Jersey. PARTICIPANTS: A total of 212 attendees at each conference. OUTCOME MEASURES: Scales measuring CLSs' knowledge of AIDS, fear of acquiring AIDS, satisfaction with employers' AIDS policies, and degree of compliance with universal blood precautions; and comparison of demographic data. RESULTS: Both surveys showed that, compared with CLSs planning to stay in the profession, CLSs considering leaving the field were more afraid of acquiring AIDS, less confident about their employers' AIDS policies, and equally knowledgeable about AIDS. CONCLUSIONS: CLSs who are considering leaving the profession are more cautious than those planning to stay, and the determinants that shape the fear of AIDS require further definition.

Attitudes and behaviors of medical technologists as a result of AIDS.

To determine the influence of AIDS on the attitudes and behaviors of medical technologists, a survey was taken which shows that one quarter are considering leaving the field. Individuals who plan to stay in the profession are less fearful of AIDS, more satisfied with the policies their organizations have established regarding AIDS, and less willing to associate a declining employment situation to AIDS. Improvement in safe laboratory practices is present in both groups, but the individuals considering a move out of the field exhibit the largest change. A surprising result in that fear of AIDS is not related to or only weakly associated with traditional demographic and occupational variables, suggesting that other more complex factors are influencing the views and work habits of medical technologists as a result of AIDS.

Fear of AIDS and attrition among medical technologists.

Attitudes toward AIDS were measured by a survey of 212 attendees at the annual meeting of the New Jersey Society for Medical Technology. Twenty five percent of the respondents were considering leaving the profession because of a fear of AIDS. In addition, almost half would not have chosen the field knowing they would be handling HIV-positive samples. This high degree of concern may be an important factor contributing to the shortage of medical technologists.

Two quick methods for Voges-Proskauer test.

Two previously described methods for rapidly performing a Voges-Proskauer (VP) test were modified so that results could be obtained even more quickly. On MacConkey agar, colonies of lactose-fermenting, VP-positive organisms usually contain enough acetoin to give a positive reaction when a dense suspension is prepared in creatine and tested directly with Barritt reagents. With this direct-screening test, no "false" positive results were seen, but 29 of 429 lactose-fermenting strains of Enterobacteriaceae initially gave "false" negative results. Thus, another technique was needed for quickly confirming negative results. A 0.2-ml amount of MR-VP Broth culture, inoculated with one colony or less, can be tested after 4 to 6 hr at 37 C by adding two drops of a 0.5% creatine solution followed by Barritt reagents. No "false" positive results were seen with 508 cultures, but one atypical coliform bacillus was negative with this method and VP positive after 48 hr of incubation in MR-VP Broth. With these two quick methods, the common VP positive organisms can be recognized within a few minutes or at most after a few hours.