Extended multiplicative signal correction as a tool for separation and characterization of physical and chemical information in Fourier transform infrared microscopy images of cryo-sections of beef loin.

Extended multiplicative signal correction (EMSC) is used to separate and to characterize physical and chemical information in spectra from Fourier transform infrared (FT-IR) microscopy. This appears especially useful for applications in infrared spectroscopy where the scatter variance in spectra changes with the chemical variance in the sample set. In these cases the chemical information of specific bands that are assigned to functional groups is easier to interpret when the scatter information is removed from the spectra. We show that scatter (physical) information in FT-IR spectra of heat-treated beef loin is related to chemical changes due to heat treatment. This information is caused by textural changes induced by the heat treatment and expressed by physical effects as the optical path length. The chemical absorbance changes introduced in the FT-IR spectra due to heat treatment are shifts in the protein region of the infrared spectrum caused by changes in the secondary structure of the proteins. If the scatter and the chemical information is not separated properly, scatter information may erroneously be interpreted as chemical information.

Identification of medically relevant microorganisms by vibrational spectroscopy.

In the recent years, vibrational spectroscopies (infrared and Raman spectroscopy) have been developed for all sorts of analyses in microbiology. Important features of these methods are the relative ease with which measurements can be performed. Furthermore, in order to obtain infrared or Raman spectra, there is only a limited amount of sample handling involved without the need for expensive chemicals, labels or dyes. Here, we review the potential application of vibrational spectroscopies for the use in medical microbiology. After describing some of the basics of the techniques, considerations on reproducibility and standardisation are presented. Finally, the use of infrared and Raman spectroscopy for the (rapid) identification of medically relevant microorganisms is discussed. It can be concluded that vibrational spectroscopies show high potential as novel methods in medical microbiology.

Guaiacol peroxidase levels in human cervical mucus: a possible predictor of ovulation.

PIP: Guaiacol peroxidase (G-Px) is an enzyme which in the human uterine epithelium has been found to be inhibited in vitro by estrogens and especially catecholestrogens. This study determines if the concentration of G-Px would vary inversely to plasma estrogens. It is hoped that this enzyme would decrease sufficiently early before ovulation to be useful as a simple predictor of ovulation in women. G-Px was serially measured in cervical mucus during the menstrual cycle of 5 healthy volunteers. Radioimmunoassay measured the following hormones in the plasma samples: 17 beta-estradiol, progesterone, luteinizing and follicle stimulating hormones. In the midcycle, G-Px levels decreased 20- to 100-fold relative to other times of the cycle, the decrease coinciding with the peak of plasma estrogens and probably causally related to them. G-Px levels were not affected by the 2nd peak of plasma estrogens, possibly because of the counter effect of progesterone. Further research should be done to determine possible hormonal control of G-Px activity. G-Px may be central to the structure and function of cervical mucus. They may have bactericidal and spermicidal properties and may play a role in sperm capacitation. The findings in this study may be beneficial in estimating optimal time for intercourse and artificial insemination in infertile patients and improving the efficacy of the periodic abstinence method of contraception by easily identifying the fertile period. In addition, the G-Px assay in cervical mucus is adaptable to a simple sensitive home test because the products of guaiacol oxidation are visible to the naked eye and drastic changes in color production can be easily perceived.^ieng

Monitoring of denaturation processes in aged beef loin by Fourier transform infrared microspectroscopy.

We present the results of a Fourier transform infrared (FT-IR) microspectroscopic study using conventional FT-IR microscopy and FT-IR imaging to detect the denaturation process during four different heating temperatures (raw, 45, 60, and 70 degrees C) spatially resolved in bovine cryosections from longissimus dorsi muscle. FT-IR imaging, employing a focal plane array detector, which allowed the simultaneous collection of spectra at 4096 pixels, enabled the investigation of the heat-induced changes in the two major meat constituents, i.e., myofibrillar and connective tissue proteins, spatially resolved. The infrared spectra of both compounds revealed that the major spectral changes involved an increase in beta-sheet and a decrease in alpha-helical structures, which appeared to be much more pronounced for the myofibers than for the connective tissue. These conformational changes could be correlated to the denaturation of the major meat proteins, such as myosin, actin, and collagen.

Coding and reimbursement mechanisms for physician services in hospice and palliative care.

Many physicians misperceive that the current coding system used to bill third-party payers in the United States does not include codes related to hospice and palliative care. This article will help physicians and hospice and palliative care providers to: 1) understand how to code for physician services related to hospice and palliative care; 2) review the documentation required to support such services; 3) understand the differences between the reimbursement mechanisms to be used when the patient is enrolled in the Medicare Hospice Benefit, and the usual reimbursement mechanisms; and 4) understand some of the approaches for funding non-physician palliative care services for patients not enrolled in the Medicare Hospice Benefit.

The role of intermolecular interactions: studies on model systems for bacterial biofilms.

The mechanical stability of biofilms and other microbial aggregates is of great importance for both the maintenance of biofilm processes and the removal of undesired biofilms. The binding forces are weak interactions such as London dispersion forces, electrostatic interactions and hydrogen bonds. In a first attempt to rank their contribution, the viscosity of solutions of extracellular polymeric substances (EPS) from a mucoid strain of Pseudomonas aeruginosa is measured. In order to distinguish the binding forces, substances are chosen which individually address the different types of bonds. Polyacrylic acid is identified as a suitable model system for EPS when molecular interactions are studied. Electrostatic interactions and hydrogen bonds are found to be the dominating forces among macromolecules within the biofilm.

A bleomycin/ifosfamide/cisplatin regimen exhibits poor activity against persistent or recurrent squamous gynecologic cancers.

Persistent or recurrent squamous malignancies of the female genital tract are usually incurable by conventional therapy, and results of single agent chemotherapy have been disappointing. We undertook this study to confirm a previously reported response rate of 69%, using a regimen of bleomycin 30U, ifosfamide 5g/m2 with mesna 6g/m2, and cisplatin 50 mg/m2 (BIP) for recurrent cervical cancer. This regimen was used to treat persistent or recurrent squamous cancers in women with cervical cancer (n = 11), vaginal cancer (n = 1) and vulvar cancer (n = 1). Results were reviewed retrospectively and toxicities graded according to the criteria of the Gynecologic Oncology Group. No complete responses were seen. One patient had a partial response (10%, 95% confidence interval 0-28%). Five patients (50%), exhibiting stable disease during therapy with BIP, progressed after cessation of therapy. Of 9 women with symptoms after one cycle. Significant toxicities included neutropenic fever (3 grade 3, 3 grade 4), emesis (1 grade 3), confusion (2 grade 4), vaginal bleeding (2 grade 3), and renal failure (1 grade 3). Eight patients were transfused with a total of 28 units of red cells. After 23 months of follow-up, all patients were dead of disease. Mean survival was 10 months. Toxicity associated with this regimen can be significant, and results appear no better than those reported with single agent therapy.

Multivariate image analysis of a set of FTIR microspectroscopy images of aged bovine muscle tissue combining image and design information.

In this paper we present an algorithm for analysing sets of FTIR microscopic images of tissue sections. The proposed approach allows one to investigate sets of many FTIR tissue images both with respect to sample information (variation from image to image) and spatial variations of tissues (variation within the image). The algorithm is applied to FTIR microscopy images of beef loin muscles containing myofibre and connective tissue regions. The FTIR microscopy images are taken of sub-samples from five different beef loin muscles that were aged for four different lengths of time. The images were investigated regarding variation due to the ageing length and due to the homogeneity of the connective tissue regions. The presented algorithm consists of the following main elements: (1) pre-processing of the spectra to overcome large quality differences in FTIR spectra and differences due to scatter effects, (2) identification of connective tissue regions in every image, (3) labelling of every connective tissue spectrum with respect to its location in the connective tissue region, and (4) analysis of variations in the FTIR microscopic images in regard to ageing time and pixel position of the spectra in the connective tissue region. Important spectral parameters characterising collagen and proteoglycan structure were determined.

Uterine horn abscess complicating pregnancy.

Uterine unicollis bicornis with one rudimentary horn is a rare event. A case is presented of an infected rudimentary system existing with an intrauterine pregnancy. The differential diagnosis of appendicitis, chorioamnionitis, premature labor, and pyelonephritis makes management of such cases difficult. The successful outcome of one such case is presented.

Surgical treatment of the elderly patient with gynecologic cancer.

One hundred and one patients with gynecologic oncologic disease who were 70 years of age or more underwent 169 surgical procedures during an eight year period. The rate of major morbidity was 22.0 per cent, and the operative mortality rate was 1.3 per cent. The one year survival rate was 86 per cent. We were unable to predict morbidity or mortality based on age, past history, American Society of Anesthesiologists class, preoperative laboratory studies or type of operation. When the group of elderly patients was compared with a control group of patients with cancer who were 60 years of age or less, there was a significantly higher rate of major morbidity in the elderly (22 versus 9 per cent), but more one year survivors (86 versus 74 per cent). We conclude that age alone should not be a deterrent to surgical management of gynecologic malignant disease. With careful perioperative management and attention to the unique problems of the elderly, acceptable surgical rates can be achieved.

Smoking, obesity, and survival in squamous cell carcinoma of the vulva.

One hundred thirty-six patients with invasive squamous cell carcinoma of the vulva were studied retrospectively to determine prognostic factors for survival. In the regression analysis, three variables were statistically significantly related to survival: smoking history, tumor size, and node status. Smokers had a 6.3 times greater risk than nonsmokers, node positivity imparted an 8.3 times greater risk than node negativity, and for each 1-cm increase in the size of the tumor, the risk of death increased by 46%. A relative decrease in survival in smokers was observed, despite a younger age and fewer positive nodes at diagnosis compared to nonsmokers. Increased surveillance in these patients may be warranted.

Prognostic indicators of survival in advanced endometrial cancer.

Advanced endometrial cancer represents 14% of all stages but 54% of all deaths attributed to endometrial cancer. From 1973 to 1990, the charts of 137 patients with endometrial cancer (Stage III and IV) treated by the section of Gynecologic Oncology at Rush Medical College were retrospectively reviewed. The log rank method was used for univariate analysis and Cox proportional hazards regression was used for multivariate analysis. The patients were stratified as follows: Stage III, 92 (67.2%), Stage IV, 45 (32.8%); Grade 1, 15 (10.9%), Grade 2, 47 (34.3%), Grade 3, 67 (48.9%); adenocarcinoma, 93 (67.9%), adenosquamous, 18 (13.1%), adenoacanthoma, 2 (1.5%), clear cell, 1 (0.7%), papillary serous, 23 (16.8%). Using univariate analysis, median survival was 1.71 years for Stage III versus 0.68 years for Stage IV. Median survival based on treatment was as follows: radiotherapy (RT) only (n = 16), 0.89 years, surgery only (n = 36), 0.75 years, preoperative RT+surgery (n = 7), 2.5 years, surgery+postoperative RT (n = 56), 2.63 years, and other treatments (hormonal only n = 12, chemotherapy only n = 1, and no treatment n = 9), 0.6 years. Patients with vaginal extension survived a median of 0.82 years, versus 2.49 years without this factor (P = 0.002). Patients with clinically apparent parametrial involvement survived a median of 0.70 years versus 2.65 years without this factor (P = 0.0003). Multivariate analysis was possible via a surgical database (n = 99). Age > 60 (P = 0.01), parametrial involvement (P = 0.04), and abdominal metastases (P = 0.003) were significant prognostic indicators. Papillary or clear cell histology, advanced grade, and mode of treatment were not significant. Patients with abdominal metastases or parametrial extension of tumor have a significant decrease in mean survival.

Angiogenesis factor in endometrial carcinoma: a new prognostic indicator?

OBJECTIVE: Tumor angiogenesis is believed to be a prognostic indicator associated with tumor growth and metastasis. Studies of angiogenesis in breast, prostate, and lung cancer, as well as melanoma, have shown that neovascularization correlates with the likelihood of metastasis and recurrences. The purpose of this study was to evaluate microvessel density as a prognostic factor in endometrial cancer. METHODS: Between 1980 and 1991 the tumor registry identified 25 patients with a diagnosis of recurrent endometrial cancer. These patients were matched with 25 patients with nonrecurrent disease for age, stage, grade, and treatment. The histologic slides of the 50 patients were reviewed. The paraffin blocks were obtained, and the area of the deepest myometrial invasion was selected for staining. The microvessels within the invasive cancer were highlighted by means of immunocytochemical staining to detect factor VIII-related antigen. Microvessels were counted by two investigators who were blinded to the patients' clinical status. Survival data were analyzed with Kaplan-Meier survival curves. RESULTS: Microvessel count was related to likelihood of recurrence, although this trend did not reach statistical significance. Patients with tumors of low capillary density had a mean survival time of 123 months. Patients with tumors of high capillary density had a mean survival time of 75 months (p = 0.02). Among patients with recurrent disease, those with a low capillary count survived a mean of 64 months. Patients with recurrent disease with tumors of high capillary density survived a mean of 45 months (p = 0.002). CONCLUSION: Angiogenesis factor correlates with survival in endometrial carcinoma.

Classification and identification of enterococci: a comparative phenotypic, genotypic, and vibrational spectroscopic study.

Rapid and accurate identification of enterococci at the species level is an essential task in clinical microbiology since these organisms have emerged as one of the leading causes of nosocomial infections worldwide. Vibrational spectroscopic techniques (infrared [IR] and Raman) could provide potential alternatives to conventional typing methods, because they are fast, easy to perform, and economical. We present a comparative study using phenotypic, genotypic, and vibrational spectroscopic techniques for typing a collection of 18 Enterococcus strains comprising six different species. Classification of the bacteria by Fourier transform (FT)-IR spectroscopy in combination with hierarchical cluster analysis revealed discrepancies for certain strains when compared with results obtained from automated phenotypic systems, such as API and MicroScan. Further diagnostic evaluation using genotypic methods-i.e., PCR of the species-specific ligase and glycopeptide resistance genes, which is limited to the identification of only four Enterococcus species and 16S RNA sequencing, the "gold standard" for identification of enterococci-confirmed the results obtained by the FT-IR classification. These results were later reproduced by three different laboratories, using confocal Raman microspectroscopy, FT-IR attenuated total reflectance spectroscopy, and FT-IR microspectroscopy, demonstrating the discriminative capacity and the reproducibility of the technique. It is concluded that vibrational spectroscopic techniques have great potential as routine methods in clinical microbiology.

Prospective study of the performance of vibrational spectroscopies for rapid identification of bacterial and fungal pathogens recovered from blood cultures.

Rapid identification of microbial pathogens reduces infection-related morbidity and mortality of hospitalized patients. Raman spectra and Fourier transform infrared (IR) spectra constitute highly specific spectroscopic fingerprints of microorganisms by which they can be identified. Little biomass is required, so that spectra of microcolonies can be obtained. A prospective clinical study was carried out in which the causative pathogens of bloodstream infections in hospitalized patients were identified. Reference libraries of Raman and IR spectra of bacterial and yeast pathogens highly prevalent in bloodstream infections were created. They were used to develop identification models based on linear discriminant analysis and artificial neural networks. These models were tested by carrying out vibrational spectroscopic identification in parallel with routine diagnostic phenotypic identification. Whereas routine identification has a typical turnaround time of 1 to 2 days, Raman and IR spectra of microcolonies were collected 6 to 8 h after microbial growth was detected by an automated blood culture system. One hundred fifteen samples were analyzed by Raman spectroscopy, of which 109 contained bacteria and 6 contained yeasts. One hundred twenty-one samples were analyzed by IR spectroscopy. Of these, 114 yielded bacteria and 7 were positive for yeasts. High identification accuracy was achieved in both the Raman (92.2%, 106 of 115) and IR (98.3%, 119 of 121) studies. Vibrational spectroscopic techniques enable simple, rapid, and accurate microbial identification. These advantages can be easily transferred to other applications in diagnostic microbiology, e.g., to accelerate identification of fastidious microorganisms.

Investigating microbial (micro)colony heterogeneity by vibrational spectroscopy.

Fourier transform infrared and Raman microspectroscopy are currently being developed as new methods for the rapid identification of clinically relevant microorganisms. These methods involve measuring spectra from microcolonies which have been cultured for as little as 6 h, followed by the nonsubjective identification of microorganisms through the use of multivariate statistical analyses. To examine the biological heterogeneity of microorganism growth which is reflected in the spectra, measurements were acquired from various positions within (micro)colonies cultured for 6, 12, and 24 h. The studies reveal that there is little spectral variance in 6-h microcolonies. In contrast, the 12- and 24-h cultures exhibited a significant amount of heterogeneity. Hierarchical cluster analysis of the spectra from the various positions and depths reveals the presence of different layers in the colonies. Further analysis indicates that spectra acquired from the surface of the colonies exhibit higher levels of glycogen than do the deeper layers of the colony. Additionally, the spectra from the deeper layers present with higher RNA levels than the surface layers. Therefore, the 6-h colonies with their limited heterogeneity are more suitable for inclusion in a spectral database to be used for classification purposes. These results also demonstrate that vibrational spectroscopic techniques can be useful tools for studying the nature of colony development and biofilm formation.