Robustness analysis of surface-guided DIBH left breast radiotherapy: personalized dosimetric effect of real intrafractional motion within the beam gating thresholds.

PURPOSE: The robustness of surface-guided (SG) deep-inspiration breath-hold (DIBH) radiotherapy (RT) for left breast cancer was evaluated by investigating any potential dosimetric effects due to the residual intrafractional motion allowed by the selected beam gating thresholds. The potential reduction of DIBH benefits in terms of organs at risk (OARs) sparing and target coverage was evaluated for conformational (3DCRT) and intensity-modulated radiation therapy (IMRT) techniques. METHODS: A total of 192 fractions of SGRT DIBH left breast 3DCRT treatment for 12 patients were analyzed. For each fraction, the average of the real-time displacement between the isocenter on the daily reference surface and on the live surface ("SGRT shift") during beam-on was evaluated and applied to the original plan isocenter. The dose distribution for the treatment beams with the new isocenter point was then calculated and the total plan dose distribution was obtained by summing the estimated perturbed dose for each fraction. Then, for each patient, the original plan and the perturbed one were compared by means of Wilcoxon test for target coverage and OAR dose-volume histogram (DVH) metrics. A global plan quality score was calculated to assess the overall plan robustness against intrafractional motion of both 3DCRT and IMRT techniques. RESULTS: Target coverage and OAR DVH metrics did not show significant variations between the original and the perturbed plan for the IMRT techniques. 3DCRT plans showed significant variations for the left descending coronary artery (LAD) and the humerus only. However, none of the dose metrics exceeded the mandatory dose constraints for any of the analyzed plans. The global plan quality analysis indicated that both 3DCRT and IMRT techniques were affected by the isocenter shifts in the same way and, generally, the residual isocenter shifts more likely tend to worsen the plan in all cases. CONCLUSION: The DIBH technique proved to be robust against residual intrafractional isocenter shifts allowed by the selected SGRT beam-hold thresholds. Small-volume OARs located near high dose gradients showed significant marginal deteriorations in the perturbed plans with the 3DCRT technique only. Global plan quality was mainly influenced by patient anatomy and treatment beam geometry rather than the technique adopted.

Surface-guided DIBH radiotherapy for left breast cancer: impact of different thresholds on intrafractional motion monitoring and DIBH stability.

PURPOSE: To compare two left breast cancer patient cohorts (tangential vs. locoregional deep-inspiration breath-hold - DIBH treatment) with different predefined beam gating thresholds and to evaluate their impact on motion management and DIBH stability. METHODS: An SGRT-based clinical workflow was adopted for the DIBH treatment. Intrafractional monitoring was performed by tracking both the respiratory signal and the real-time displacement between the isocenter on the daily reference surface and on the live surface ("SGRT shift"). Beam gating tolerances were 5 mm/4 mm for the SGRT shifts and 5 mm/3 mm for the gating window amplitude for breast tangential and breast + lymph nodes locoregional treatments, respectively. A total of 24 patients, 12 treated with a tangential technique and 12 with a locoregional technique, were evaluated for a total number of 684 fractions. Statistical distributions of SGRT shift and respiratory signal for each treatment fraction, for each patient treatment, and for the two population samples were generated. RESULTS: Lateral cumulative distributions of SGRT shifts for both locoregional and tangential samples were consistent with a null shift, whereas longitudinal and vertical ones were slightly negative (mean values < 1 mm). The distribution of the percentage of beam on time with SGRT shift > 3 mm, > 4 mm, or > 5 mm was extended toward higher values for the tangential sample than for the locoregional sample. The variability in the DIBH respiration signal was significantly greater for the tangential sample. CONCLUSION: Different beam gating thresholds for surface-guided DIBH treatment of left breast cancer can impact motion management and DIBH stability by reducing the frequency of the maximum SGRT shift and increasing respiration signal stability when tighter thresholds are adopted.

Hyaluronan-estradiol nanogels as potential drug carriers to target ER+ breast cancer cell line.

An innovative hyaluronan-based nano-delivery system is proposed for the active targeting towards ER+ breast cancer. Hyaluronic acid (HA), an endogenous and bioactive anionic polysaccharide, is functionalized with estradiol (ES), a sexual hormone involved in the development of some hormone-dependent tumors, to give an amphiphilic derivative (HA-ES) able to spontaneously self-assemble in water to form soft nanoparticles or nanogels (NHs). The synthetic strategy used to obtain the polymer derivatives and the physico-chemical properties of the obtained nanogels (ES-NHs) are reported. ES-NHs ability to entrap hydrophobic molecules has also been investigated, by loading curcumin (CUR) and docetaxel (DTX), both able to inhibit the growth of ER+ breast cancer. The formulations are studied for their capability to inhibit the growth of the MCF-7 cell line, thus evaluating their efficacy and potential as a selective drug delivery systems. Our results demonstrate that ES-NHs have not toxic effects on the cell line, and that both ES-NHs/CUR and ES-NHs/DTX treatments inhibit MCF-7 cell growth, with ES-NHs/DTX effect higher than that of free DTX. Our findings support the use of ES-NHs to deliver drugs to ER+ breast cancer cells, assuming a receptor-dependent targeting.

Underprescription of medications in older adults: causes, consequences and solutions-a narrative review.

PURPOSE: Under-prescription is defined as the omission of a medication that is indicated for the treatment of a condition or a disease, without any valid reason for not prescribing it. The aim of this review is to provide an updated overview of under-prescription, summarizing the available evidence concerning its prevalence, causes, consequences and potential interventions to reduce it. METHODS: A PubMed search was performed, using the following keywords: under-prescription; under-treatment; prescribing omission; older adults; polypharmacy; cardiovascular drugs; osteoporosis; anticoagulant. The list of articles was evaluated by two authors who selected the most relevant of them. The reference lists of retrieved articles were screened for additional pertinent studies. RESULTS: Although several pharmacological therapies are safe and effective in older patients, under-prescription remains widespread in the older population, with a prevalence ranging from 22 to 70%. Several drugs are underused, including cardiovascular, oral anticoagulant and anti-osteoporotic drugs. Many factors are associated with under-prescription, e.g. multi-morbidity, polypharmacy, dementia, frailty, risk of adverse drug events, absence of specific clinical trials in older patients and economic factors. Under-prescription is associated with negative consequences, such as higher risk of cardiovascular events, worsening disability, hospitalization and death. The implementation of explicit criteria for under-prescription, the use of the comprehensive geriatric assessment by geriatricians, and the involvement of a clinical pharmacist seem to be promising options to reduce under-prescription. CONCLUSION: Under-prescription remains widespread in the older population. Further studies should be performed, to provide a better comprehension of this phenomenon and to confirm the efficacy of corrective interventions.

[Size distribution of amphibole fibres from lung and pleural tissues sampled from mesothelioma cases due to environmental exposure]. / Caratterizzazione dimensionale di fibre anfiboliche nel polmone e nella pleura di casi di mesotelioma da esposizione ambientale.

BACKGROUND: It has been suggested that malignant mesothelioma might be mainly or only connected with the action of short and ultrathin fibres. On the basis of this hypothesis fibres less than 5 microm long and 0.2-0.1 microm thick would enter the pulmonary-pleura barrier and reach the parietal pleura thus inducing mesothelioma. The hypothesis raised a stimulating scientific discussion. OBJECTIVES: The aim of this communication is to report the initial results obtained comparing the size of amphibole fibres from healthy lung tissue with those from pleural tissue sampled from subjects whose death cause of death was mesothelioma. METHODS: Four mesothelioma cases due to environmental exposure were studied; the fibres were categorized by scanning electron microscopy; for every fibre, length and diameter were measured and the mineral type was defined by its chemical composition determined by X-ray microanalysis. RESULTS: The most important characteristics of the detected fibres were: the average length offibres from the lung and pleural tissues taken from the same subject did not difer, in all cases, by more than 10-12%; 95% offibres found in the lung tissues of all subjects had a length greater than 5 microm; 98% of fibres found in the pleural tissues had a length greater than 5 microm; the average diameter of the fibres found in the pleural tissues was 70% of the diameter of the fibres from the lung tissues. CONCLUSIONS: The experimental data obtained in this study confirm the correlation between malignant mesothelioma and the presence in the lung and pleural tissues of fibres with a length greater, even much greater, than 4-5 microm; thus the hypothesis that the chief factors inducing mesothelioma are the "ultrashort" and "ultrathin" fibres appears rather weak.

Maternal immunization of mice with group B streptococcal type III polysaccharide-beta C protein conjugate elicits protective antibody to multiple serotypes.

Group B streptococcal infection is a major cause of neonatal mortality. Antibody to the capsular polysaccharide protects against invasive neonatal disease, but immunization with capsular polysaccharides fails to elicit protective antibody in many recipients. Conjugation of the polysaccharide to tetanus toxoid has been shown to increase immune response to the polysaccharide. In animal models, C proteins of group B streptococci are also protective determinants. We examined the ability of the beta C protein to serve in the dual role of carrier for the polysaccharide and protective immunogen. Type III polysaccharide was covalently coupled to beta C protein by reductive amination. Immunization of rabbits with the polysaccharide-protein conjugate elicited high titers of antibody to both components, and the serum induced opsonophagocytic killing of type III, Ia/C, and Ib/C strains of group B streptococci. Female mice were immunized with the conjugate vaccine and then bred; 93% of neonatal pups born to these dams vaccinated with conjugate survived type III group B streptococcal challenge and 76% survived type Ia/C challenge, compared with 3% and 8% survival, respectively, in controls (P < 0.001). The beta C protein acted as an effective carrier for the type III polysaccharide while simultaneously induced protective immunity against beta C protein--containing strains of group B streptococci.

Immunogenicity in animals of a polysaccharide-protein conjugate vaccine against type III group B Streptococcus.

The native capsular polysaccharide of type III group B Streptococcus elicits a specific antibody response in only 60% of nonimmune human subjects. To enhance the immunogenicity of this polysaccharide, we coupled the type III polysaccharide to tetanus toxoid. Prior to coupling, aldehyde groups were introduced on the polysaccharide by controlled periodate oxidation, resulting in the conversion of 25% of the sialic acid residues of the polysaccharide to residues of the 8-carbon analogue of sialic acid, 5-acetamido-3,5-dideoxy-D-galactosyloctulosonic acid. Tetanus toxoid was conjugated to the polysaccharide by reductive amination, via the free aldehyde groups present on the partially oxidized sialic acid residues. Rabbits vaccinated with the conjugate vaccine produced IgG antibodies that reacted with the native type III group B streptococcal polysaccharide (3/3 rabbits), while rabbits immunized with the unconjugated type III polysaccharide failed to respond (0/3 rabbits). Sera from animals receiving conjugate vaccine opsonized type III group B streptococci for phagocytic killing by human peripheral blood leukocytes, and protected mice against lethal challenge with live type III group B streptococci. The results suggest that this method of conjugation to a carrier protein may be a useful strategy to improve the immunogenicity of the type III group B Streptococcus polysaccharide in human subjects.

Effects of chain length on the immunogenicity in rabbits of group B Streptococcus type III oligosaccharide-tetanus toxoid conjugates.

One method to improve the immunogenicity of polysaccharide antigens is the covalent coupling of the native polysaccharide or a derivative oligosaccharide to a carrier protein. In general, T cell-dependent properties are enhanced in conjugates of smaller saccharides, but a conformational epitope of the native polysaccharide may be better expressed in conjugates of larger saccharides. We have reported previously the synthesis and immunogenicity in animals of an oligosaccharide-tetanus toxoid conjugate vaccine against type III group B Streptococcus. In this study, we sought to determine the optimal size of group B Streptococcus type III oligosaccharide for use in a conjugate vaccine by evaluating the relative immunogenicity of conjugate vaccines containing oligosaccharides that were twofold smaller (7,000 Mr) or larger (27,000 Mr) than that reported previously (14,500 Mr). All three type III oligosaccharide conjugate vaccines were immunogenic in rabbits, in contrast to native, uncoupled group B Streptococcus type III polysaccharide. However, with respect to eliciting specific antibodies that were protective in vivo, the vaccine containing the intermediate-size oligosaccharide was superior to the smaller or larger conjugate vaccine. Analysis of opsonic activity of vaccine-induced antibodies demonstrated a predominance of IgG antibodies, thought to reflect T cell dependence, in response to shorter chain length conjugates, while the conformational epitope of the native polysaccharide was maximally expressed on longer chain length conjugates. These opposing trends may account for the optimal immunogenicity of an intermediate-size group B Streptococcus type III oligosaccharide conjugate vaccine.

Immune response to type III group B streptococcal polysaccharide-tetanus toxoid conjugate vaccine.

Group B Streptococcus (GBS) is an important perinatal pathogen. Because transplacentally acquired maternal antibodies to the GBS capsular polysaccharides (CPS) confer protection, prevention of infant disease may be possible after immunization of women. Unfortunately, the purified CPS of GBS are only variably immunogenic in adults; therefore to enhance immunogenicity we have designed and developed a CPS-protein conjugate vaccine. The lability of a conformationally dependent epitope on the III CPS containing a critical sialic acid residue was important to consider in vaccine design. 100 women were randomized to receive GBS type III CPS-tetanus toxoid conjugate (III-TT) vaccine at one of three doses; unconjugated GBS type III CPS; or saline. Serum samples were obtained before immunization and 2, 4, 8, and 26 wk thereafter, and specific antibody to type III CPS was measured. Vaccines were well tolerated. In sera from recipients of the highest dose of III-TT, CPS-specific IgG levels rose from a geometric mean of 0.09 microg/ml before immunization to 4.53 microg/ml 8 wk later, whereas levels in recipients of unconjugated type III CPS rose from 0.21 microg/ml to 1.41 microg/ml. Lower doses resulted in lower antibody levels. A > or = 4-fold rise in antibody concentration was achieved in 90% of recipients of III-TT compared with 50% of those that received III CPS (P = 0.0015). Antibodies evoked by the conjugate vaccine recognized a conformationally dependent epitope of the III-CPS, promoted opsonophagocytosis and killing of GBS, and, after maternal immunization, protected neonatal mice from lethal challenge with type III GBS. We conclude that directed coupling of type III GBS polysaccharide to a carrier protein yielded a conjugate vaccine with preserved expression of a highly labile conformational epitope involving sialic acid and enhanced immunogenicity compared with uncoupled CPS.

Use of tamoxifen in pT1a-pT1b, pN0 breast cancer.

PURPOSE: To evaluate if in low-risk breast cancer patients (pT1a-pT1b, pN0) tamoxifen can reduce local recurrence and improve survival. METHODS: Retrospectively 700 patients were analyzed. All patients were treated from 1980 to 2003 with conservative surgery plus radiotherapy at the University of Florence. No patients were treated with adjuvant chemotherapy. Tamoxifen was prescribed in 359 patients (51.3%). The crude probability of survival (or local recurrence) was estimated by using Kaplan-Meier method, and survival (or local recurrence) comparisons were carried out using Cox proportional hazard regression models. RESULTS: The univariate analysis for specific survival showed that only histological type and local recurrence were significant prognostic factors (log rank test: p=0.02 and p<0.0001, respectively). The Cox regression model by stepwise selection confirmed lobular histological type (p=0.008; HR: 3.83, 95% CI: 1.31-11.21) and local recurrence (p<0.001; HR: 9.05, 95% CI: 3.05-26.82) as independent prognostic factors for disease specific survival. For local disease free survival, multivariate analysis did not show any significant parameters. CONCLUSION: In our series tamoxifen did not seem to improve disease specific survival and local disease specific survival. The number of events in terms of death for cancer or in terms of local recurrence is too small in this group of patients. However, according to our results we suggest not to prescribe tamoxifen in patients affected by pT1a-pT1b, pN0 breast cancer.

Airborne silica levels in an urban area.

In order to evaluate the exposure levels of the general population we studied the concentrations of silica particles in the inhalable particulate fraction (PM10) in different meteorological-climate periods in an urban area of Rome. In order to determine the concentration and the granulometric spectrum of silica particles, PM10 sampled by a cascade impactor was analysed by X-ray diffractometry (XRD) and by scanning electron microscopy equipped with a thin-window system for X-ray microanalysis (SEM/EDX). Over the period September 2004-October 2005 the abundance of silica particles as evaluated by SEM/EDX ranged from 1.6 to 10.4% of the total PM10 particulate, with a weight concentration of free crystalline silica, evaluated by XRD, in the range 0.25-2.87 microg/m3. The mean diameter of silica particles ranged from 0.3 to 10.5 microm, with more than 87% of particles having a diameter of less than 2.5 microm. The correlations between SEM/EDX and XRD data seem to suggest that the airborne silica particles in the urban location studied were mainly in the form crystalline silica. A strong relationship was found between the meteorological-climate conditions and the concentration level of free crystalline silica. This result suggests that the Southern winds from the Sahara desert carry an important amount of silica particles into Mediterranean Europe.

A pilot study on the content and the release of Ni and other allergenic metals from cheap earrings available on the Italian market.

The capability of alloys used in cheap jewellery to release metal ions on contact with the skin causing allergic contact dermatitis (ACD) is generally acknowledged. To reduce the diffusion of the Ni-induced ACD the Council Directive 94/27/EC [Council Directive 94/27/EC of 30 June 1994. Official Journal L 188, 22/07/1994, 1.] limited the total Ni content in alloys and its release rate in artificial sweat. In this work, three different aspects were explored: i) the frequency of skin sensitization to Ni-containing earrings in patients before and after the introduction of the Directive's limit; ii) metal composition of alloys by X-ray analysis; iii) metal leaching in artificial sweat followed by Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICP-MS) quantification. Well-known allergenic metals, as Ni, Cr and Co, and possible emergent allergens, as Al, Ag, Au, Cd, Cu, Fe, Ir, Mn, Pb, Pd, Pt, Rh, Sn, V and Zn, were studied. Results showed that the frequency of allergy due to earrings did not decrease after the introduction of the Ni limit: in 1994 and in 2005 patients positive to Ni patch tests were 54.3% and 53.5%, respectively. The earring components analyzed were Fe-based or alloys of Cu/Zn or Fe/Cr/Ni, plated with a thin film of precious metal (Ag, Au) which, in several cases, was combined with a Ni layer beneath. Five out of 10 items were not in compliance with the Ni Directive 94/27/EC having a total Ni content >0.05%. In three cases the release of Ni concentrations was higher than the safe sensitizing limit given by the above mentioned Regulation (i.e., <0.5 microg/cm(2)/week). The release of Cu and Zn was very variable among the different pieces (Cu: 0.134-30.9 microg/cm(2)/week; Zn: 0.141-160 microg/cm(2)/week); two objects released high amounts of Fe (358 and 586 microg/cm(2)/week) and one released considerable Mn (21 microg/cm(2)/week). Lead was released from 70% of the objects, while Ag, Al, Cd, Co, Cr and Sn from ca. 30% of the items and concentrations of these elements were well below 0.5 microg/cm(2)/week. Vanadium was released by only one item whereas Au, Ir, Pd, Pt and Rh were never leached.

[The "silica" component in the PM10 of an urban site]. / La componente "silice" nel PM10 di un ambiente urbano.

BACKGROUND: In vivo and in vitro toxicological studies have shown that the aged fracturated crystalline silica, which is a component of airborne particulate, exerts an important inflammatory action on airways. The evaluation of the concentration level of airborne crystalline silica in an urban area is an important research subject in order to determine the exposure levels of the general population. OBJECTIVES: The aim was to study the seasonal trend of the quartz (the most common form of crystalline silica) concentration levels in the particulate inhalable faction (PM10) in the urban area of Rome. METHODS: PM10, sampled by a cascade impactor, was analysed by scanning electron microscopy, equipped with a thin-window system for X-ray microanalysis (SEM/EDX) for qualitative analysis. Parallely the concentration levels of quartz in the particulate were determined by X-ray diffractometry (XRD) for quantitative analysis, using the NIOSH 7500 method (NIOSH, 1994). RESULTS: From September 2004 to October 2005 the abundance of silica particles, evaluated by SEM/EDX was in the range 1.6/10.4%, with a concentration level of free crystalline silica in the range 0.25/2.87 microg/mi. The equivalent diameter of silica particles ranged from 0.3 to 10.5 mircom, moreover, more than 87% of particles showed a diameter less than 2.5 microm. CONCLUSIONS: The correlations between SEM/EDX and XRD data seem to suggest that the airborne silica particles in the urban location studied consisted mostly of crystalline silica. Moreover, the data suggest the existence of a significant contribution of silica particles due to southwest wind carrying a fine dust from the Sahara desert to Mediterranean Europe.

Multinucleation and pro-inflammatory cytokine release promoted by fibrous fluoro-edenite in lung epithelial A549 cells.

An unusual cluster of malignant mesothelioma was evidenced in Biancavilla, a Sicily village where no inhabitant had been significantly and professionally exposed to asbestos. Mineralogical and environmental studies led to the identification of a new prismatic amphibole, named fluoro-edenite. We previously reported, by using the human lung epithelial A549 cells, that prismatic fluoro-edenite was unable to induce changes that could be somehow related to cellular transformation, and this was in accordance with studies carried out in vivo. More recently, a fibrous amphibole with a composition very similar to that of prismatic fluoro-edenite, was identified in Biancavilla. This fibrous fluoro-edenite was shown to induce mesothelioma in rats. In keeping with this effect in vivo, in the present work we observed multinucleation and spreading, common features of transformed cells, as well as pro-inflammatory cytokine release in A549 cells. Such cell changes occurred without interfering with the passage of the resulting multinucleated cells through the cell cycle and without condemning cells to death. Hence, in lung epithelial cells, fibrous fluoro-edenite behaved similarly to the unrelated asbestos type crocidolite, whose connection with severe inflammation and cancer of the lung is renowned.

Nature and extent of the exposure to fibrous amphiboles in Biancavilla.

An epidemiological and environmental study in the Biancavilla area (Sicily, Italy) was recently prompted by an impressively high incidence of malignant pleural mesothelioma. Epidemiology suggested an environmental contamination by amphibole fibres rather than risks related to a specific occupational activity. The aim of this study is to describe the diffusion of fibrous amphiboles in the area and identify their source. Fibrous amphiboles were found in the products from the local quarries, which had been used for years to build houses. After sampling all around Biancavilla, three sites were detected and they were characterized by an abundant presence of mineral fibres. Fibrous amphiboles were also recovered from building materials (mortar and plasters) and airborne particulates sampled in urban sites with high dust emissions due mainly to unpaved roads. Moreover, amphibole fibres were detected in the lung tissue of a woman who died of pleural mesothelioma. The results of this study suggest that the amphibole fibre diffusion in the Biancavilla environment lasted for many years and had been maximum during the sixties and the seventies with the uncontrolled development of the local building industry. Today, the environmental situation results to be changed following both the closing of the stone quarries and the urbanization works after 2001, above all the asphalting of dusty roads. Anyway sporadic mesothelioma cases have still to be expected in the next years.

Influence of particle size and chemical composition on efficiency of clearance mechanisms: electron microscopy studies on humans.

This article compares the presence of solid particles in lung parenchyma samples collected from accident victims and in bronchoalveolar lavage fluid taken from patients diagnosed with pulmonary carcinoma. Analysis by electron microscopy showed differences in particle size between the two groups, which could be attributable both to differences in original particle size and to their solubility in the biological environment.

Malignant peritoneal mesothelioma in a 17-year-old boy with evidence of previous exposure to chrysotile and tremolite asbestos.

We describe a case of malignant peritoneal mesothelioma arising in a 17-year-old boy. The diagnosis was based on a comprehensive study including light microscopy, histochemistry, immunohistochemistry, evaluation of the clinical course, and autopsy examination. Analytical transmission electron microscopy showed a concentration of 510,000 asbestos fibers/g dry lung tissue. The fibers were represented by chrysotile (62%) and tremolite (38%) asbestos. About 40% of the total fibers were longer than 5 microns. The presence of tremolite fibers was probably due to environmental exposure to contaminated cosmetic talc. This is the first reported case of pathologically proven exposure to asbestos dust in malignant mesothelioma of childhood and adolescence.

Purification of preparative quantities of group B Streptococcus type III oligosaccharides.

Many bacterial capsular polysaccharides are regularly repeating units of oligosaccharides. Bacterial oligosaccharides have been used in neoglycoconjugate vaccines and as reagents in the study of specific antibody binding. Unfortunately, separation methods have not been adequate for the purification of preparative quantities of bacterial oligosaccharides. Here we describe a size-exclusion procedure that resulted in the resolution of group B Streptococcus type III oligosaccharides composed of 4-25 sugars.

Characterization of vaginal & rectal colonization with multiple serotypes of group B streptococci using multiple colony picks.

BACKGROUND & OBJECTIVES: There is paucity of information on vaginal and rectal colonization with multiple serotypes of group B streptococci (GBS). As part of an ongoing cohort study evaluating the natural history of vaginal and rectal colonization by GBS, the colonization with multiple serotypes was studied in 102 non-pregnant women aged 18-30 yr. METHODS: Up to ten separate colony picks of beta-haemolytic streptococci (total 1515 isolates) were selected from vaginal and rectal primary culture plates. The colonies were identified as GBS, and their capsular polysaccharides (CPS) serotypes determined using monospecific rabbit antisera for types Ia-VIII by double immunodiffusion in agarose (DID). A colony dot immunoblot (DB) assay, using monospecific rabbit antisera to purified type polysaccharides conjugated to tetanus toxoid, was developed to serotype efficiently the multiple colony picks of GBS. RESULTS: The CPS serotype distribution, examining only the 177 "a" or first colony picks from the 102 patients, was 30.5 per cent for Ia; 28.2 per cent for type III; 15.3 per cent for type II; and 13.6 per cent for type V. Only 2.8 per cent were nontypeable. Eighty of the 102 patients (78.4%) were colonized with only one serotype; 20 (19.6%) had two serotypes and two patients (2%) had three serotypes in their vaginal and/or rectal paired cultures. Overall, 91.9 per cent of the culture sites colonized with one to three CPS types (from the total number of colonies picked) were identified with a minimum of three colony picks. In 75 patients with vaginal/rectal pairs the GBS serotype concordance of only the "a" colony was 89.3 per cent and concordance decreased to 80 per cent when the serotype concordance of the total colony picks was analyzed. INTERPRETATION & CONCLUSION: In conclusion, there was a relatively high prevalence of serotype nonconcordance in this population, and 21.6 per cent of patients had multiple GBS serotypes.

Mineral particles in bronchoalveolar lavage fluid (BALF): an attempt at designing a quantitative model.

The author examined by morphology, chemical composition, and crystalline structure, approximately 2 500 mineral particles from bronchoalveolar lavage fluids obtained from 25 residents of Rome. In addition, the author obtained the same structural data for approximately 3000 inhalable particles present in the atmosphere in Rome. The author constructed a model of the concentration and granulometry of the different types of mineral particles in bronchoalveolar lavage fluids, by estimating the clearance times of the different particle classes. The author based the model on the following: (a) data relative to the inhalable particulate to which involved subjects were exposed, (b) updated knowledge about the processes of deposition and retention of the mineral particulate in the human respiratory tract, and (c) the hypothesis that the mineral particle pattern in bronchoalveolar lavage fluid reflects the pattern of particulate in lung parenchyma. Finally, the author compared the model with the particulate pattern observed in the bronchoalveolar lavage fluid samples. Despite some drastic approximations, the model satisfactorily fits the data obtained from the experimental research on mineral particulate in bronchoalveolar lavage fluid.