Supernatant Fluid from Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration for Rapid Next-Generation Sequencing

Introduction/Objective

The aims of our study were to optimize the workflow of non-small cell carcinoma (NSCC) endobronchial ultrasound-guided bronchoscopy with transbronchial needle aspiration (EBUS-TBNA) samples to maximize tissue available for next-generation sequencing (NGS), preserve formalin-fixed paraffin-embedded (FFPE) cell blocks (CBs) for future testing, and shorten turnaround time (TAT) of NGS results. We evaluated the performance of supernatant fluid (SNF) processed from a dedicated aspirate for NGS testing.

Methods/Case Report

20 EBUS-TBNA samples positive for NSCC on rapid on-site evaluation were collected and processed using a new workflow (Figure 1). Five aspirates were collected in formalin. One additional dedicated pass was collected fresh and centrifuged. The resulting cell pellet was added to the passes in formalin for FFPE CB processing. The SNF was recentrifuged. DNA and RNA were extracted from concentrated SNF for targeted testing using the Oncomine™ Precision Assay (Thermo Scientific™, Waltham, MA). NGS results from the corresponding FFPE CBs were used as “controls” for comparison.

Results (if a Case Study enter NA)

A total of 31 mutations were detected in SNF (Table 1). The most frequently mutated genes were TP53 (35%), EGFR (23%), KRAS (13%), CTNNB1 (6%), and ERBB2 (6%). EGFR and KRAS amplification, CDKN2A deletion, and SQSTM1-NTRK3 fusion alteration were also detected. There was 100% concordance between the mutations detected in SNF and corresponding FFPE CBs with comparable variant allele frequencies. TAT of NGS results was 1 day for SNF compared to 4 – 10 days for FFPE CB.

Conclusion

In our study, we were able to demonstrate the usefulness of NGS on SNF to provide reliable, rapid molecular results. This testing strategy was successfully incorporated into the workflow for tissue handling and processing between our clinical, cytopathology, and molecular teams. Molecular results were available at the same time as the cytologic diagnosis, allowing for timely reporting of a comprehensive diagnosis. This approach is particularly useful in patients with advanced disease requiring urgent management.

A retrospective observational study of people with Type 1 diabetes with self-reported severe hypoglycaemia reveals high level of ambulance attendance but low levels of therapy change and specialist intervention

AIM

To evaluate the impact of severe hypoglycaemia on NHS resources and overall glycaemic control in adults with Type 1 diabetes.

METHODS

An observational, retrospective study of adults (aged ≥ 18 years) with Type 1 diabetes reporting one or more episodes of severe hypoglycaemia during the preceding 24 months in 10 NHS hospital diabetes centres in England and Wales. The primary outcome was healthcare resource utilization associated with severe hypoglycaemia. Secondary outcomes included demographic and clinical characteristics, diabetes control and pathway of care.

RESULTS

Some 140 episodes of severe hypoglycaemia were reported by 85 people during the 2-year observation period. Ambulances were called in 99 of 140 (71%) episodes and Accident and Emergency attendance occurred in 26 of 140 (19%) episodes, whereas 29 of 140 (21%) episode required no immediate help from healthcare providers. Participants attended a median of 5 (range 0-58) diabetes clinic consultations during the observation period; 13% (70 of 552) of all consultations were severe hypoglycaemia-related. Of the HbA1c measurements recorded closest prior to severe hypoglycaemia (n = 119), only 7 of 119 measurements were < 48 mmol/mol (< 6.5%) and mean HbA1c was 70 (sd 19) mmol/mol (8.5%, sd 1.7%). Some 119 changes to diabetes treatment were recorded during the observation period (median/person 0;, range 0-11), of which 52 of 119 changes (44%) followed severe hypoglycaemic events.

CONCLUSIONS

We observed a high level of ambulance service intervention but surprisingly low levels of hypoglycaemia follow-up, therapy change and specialist intervention in people self-reporting severe hypoglycaemia. These results suggest there may be important gaps in care pathways for people with Type 1 diabetes self-reporting severe hypoglycaemia.

Bethesda 2014: improving on a paradigm shift

The third iteration of the Bethesda System terminology manual was recently published. This update included changes in the reporting of benign endometrial cells, and guidance for special adequacy situations and for cases in which low grade squamous intraepithelial lesions are accompanied by some cells suggesting that a high grade lesion might also be present. In addition, the manual was increased in size to include more illustrations with special studies and comparisons to histology, a greatly increased reference list, and a new chapter devoted to the modern practice of risk-based management. The third edition of the Bethesda manual is meant to serve as a primary reference for the practice of gynecologic cytology designed to provide a uniform system of reporting Worldwide for clinical, teaching, and research purposes.

Cupriavidus pauculus (Ralstonia paucula) concomitant meningitis and septicemia in a neonate: first case report from India

Ralstonia paucula (formerly classified as CDC (Centre for Disease Control) group IVc-2, Wautersia paucula; recently renamed as Cupriavidus pauculus) is an environmental Gram-negative bacillus isolated from water sources and can cause serious human infections. Patients recover bacteriologically indicating low virulence. A total of 32 cases have been reported world-wide, but no isolation has ever been reported from cerebrospinal fluid or in India. The first case of R. paucula meningitis and septicemia is being reported here along with the brief summary of cases reported world-wide.

Fifteen-year trends and predictors of preparation for pregnancy in women with pre-conception Type 1 and Type 2 diabetes: a population-based cohort study

AIMS

To investigate trends in indicators of preparation for pregnancy in women with Type 1 and Type 2 diabetes and explore their predictors.

METHODS

Data on 2293 pregnancies delivered during 1996-2010 by women with Type 1 (n = 1753) and Type 2 (n = 540) diabetes were obtained from the Northern Diabetes in Pregnancy Survey. Multiple logistic regression was used to analyse the relationship between potential predictors and three indicators of inadequate pregnancy preparation: non-attendance for pre-conception care; no pre-conception folate consumption; and peri-conception HbA(1c) ≥ 53 mmol/mol (≥ 7%).

RESULTS

Overall, 40.3% of women with diabetes attended pre-conception care, 37.4% reported pre-conception folate consumption, and 28.2% had adequate peri-conception HbA1c . For all patients, pre-conception folate consumption improved over time, while peri-conception glucose control did not. Attendance for pre-conception care for women with Type 1 diabetes significantly declined. Residence in deprived areas, smoking and younger maternal age (for women aged < 35 years) were independently associated with all three indicators of inadequate preparation for pregnancy. Additional predictors of inadequate peri-conception HbA(1c) were: Type 1 diabetes (adjusted odds ratio 5.51, 95% CI 2.71-11.22), longer diabetes history (adjusted odds ratio 1.16, 95% CI 1.09-1.23 per year increase for those with < 15 years' diabetes duration), non-white ethnicity (adjusted odds ratio 3.13, 95% CI 1.23-7.97) and higher BMI (adjusted odds ratio 1.05, 95% CI 1.01-1.09 per 1-kg/m(2) increase). Non-attendance for pre-conception care was additionally associated with Type 2 diabetes (P = 0.003) and multiparity (P < 0.0001).

CONCLUSIONS

There are socio-demographic inequalities in preparation for pregnancy among women with diabetes. Women with Type 2 diabetes were less likely to attend pre-conception care. Pre-conception services need to be designed to maximize uptake in all groups.

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA): experience of an academic centre in the USA

OBJECTIVES

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has become widely accepted as an effective modality for obtaining tissue for primary diagnosis and staging. We have been using EUS-FNA since July 2001 and herein we summarize our experience over a 5-year period.

METHODS

A computer-based search for in-house EUS-FNA was performed in the pathology database from July 2001 to October 2006. To calculate the sensitivity, specificity and accuracy of EUS-FNA, the cytology diagnosis was compared with the surgical follow-up.

RESULTS

A total of 951 EUS-FNAs were performed during the study period and included 279 pancreatic solid lesions, 186 pancreatic cyst lesions, 249 lymph node aspirations, 111 gastrointestinal (GI) tract submucosal lesions, and 126 miscellaneous lesions. EUS-FNA had a very high sensitivity and accuracy for solid pancreatic lesions (94.7 and 97.7%, respectively), low sensitivity and accuracy but high specificity (47, 64.8 and 95%, respectively) for cystic lesions. Cyst fluid carcinoembryonic (CEA) levels were significantly higher in mucinous neoplasms than non-neoplastic cysts. EUS-FNA also had very high sensitivity and specificity for detecting metastatic carcinoma in lymph nodes (95 and 100%, respectively). GI submucosal spindle cell tumours were further classified with immunohistochemical stains performed either on a cell block or a core biopsy obtained via EUS guidance.

CONCLUSIONS

EUS-FNA has a very high sensitivity and accuracy for pancreatic solid lesions, but the sensitivity for cystic lesions is generally low. Cyst fluid chemical analysis for CEA is helpful, but the overlap between mucinous neoplasm and non-neoplastic cysts is significant. Recognizing GI contamination is important and immunohistochemical stains are useful for GI submucosal spindle cell lesions.

Evaluation of chemical degradation of a trivalent recombinant protein vaccine against botulinum neurotoxin by LysC peptide mapping and MALDI-TOF mass spectrometry

Vaccines utilizing recombinant protein antigens typically require an adjuvant to enhance immune response in the recipients. However, the consequences of antigen binding to adjuvant on both the short- and long-term stability of the protein remain poorly defined. In our companion paper (Vessely et al., in press, J Pharm Sci), we characterized the effects of binding to adjuvant on the conformation and thermodynamic stability of three antigen variants for botulinum vaccines: rBoNTA(H(c)), rBoNTB(H(c)), and rBoNTE(H(c)). In the current study, we evaluated the effect of binding to adjuvant (Alhydrogel, aluminum hydroxide) on chemical stability of these antigens during long-term storage in aqueous suspension. We developed methods that employ LysC peptide mapping in conjunction with MALDI-TOF mass spectrometry. Peptide maps were developed for the proteins for a vaccine formulation of rBoNTE(H(c)) as well as a trivalent rBoNT(H(c)) vaccine formulation. This method provided high sequence coverage for the proteins in part due to the implementation of a postdigestion elution fractionation method during sample preparation, and was also successfully utilized to evaluate the chemical integrity of adjuvant-bound rBoNT(H(c)) protein antigens. We found that all three of the rBoNT(H(c)) proteins were susceptible to degradation via both oxidation and deamidation. In many cases, such reactions occurred earlier with the adjuvant-bound protein formulations when compared to the proteins in control samples that were not bound to adjuvant. Additionally, some chemical modifications were found in the adjuvant-bound protein formulations but were not detected in the unbound solution controls. Our studies indicate that binding to aluminum-based adjuvants can impact the chemical stability and/or the chemical degradation pathways of protein during long-term storage in aqueous suspension. Furthermore, the methods we developed should be widely useful for assessing chemical stability of adjuvant-bound recombinant protein antigens.

Stability of a trivalent recombinant protein vaccine formulation against botulinum neurotoxin during storage in aqueous solution

The adsorption of recombinant botulinum neurotoxin (BoNT) protein-derived vaccine antigens to aluminum salt adjuvants has been previously studied for the development of a trivalent vaccine against the neurotoxins (Vessely et al., in press, J Pharm Sci). The current paper describes an investigation of the stability of recombinant BoNT antigens adsorbed to aluminum salt adjuvants during storage in aqueous solution. Both chemical and physical changes occurred during storage. Phosphate groups in the buffer exchanged with hydroxyl groups on the adjuvant surface. The resulting changes in solution pH and adjuvant surface chemistry promoted more favorable electrostatic interaction between the BoNT proteins and the surface, possibly increasing the affinity of the proteins for the surface during storage. Fluorescence and UV spectroscopy suggested changes to protein structure during storage, whereas differential scanning calorimetry showed changes to thermal processes related to protein conformation and/or surface adsorption. The consequence of the chemical and physical changes to the proteins was a decrease in the ability to desorb protein from the adjuvant surface during storage. Overall, the results of this study emphasize the utility of a thorough characterization of the interactions between protein antigens and aluminum salt adjuvants.

Does anesthetic induction for Cesarean section with a combination of ketamine and thiopentone confer any benefits over thiopentone or ketamine alone? A prospective randomized study

BACKGROUND

The aim of this study was to evaluate the benefit of a combination of thiopentone and ketamine over either of these drugs alone as an induction agent for Cesarean section.

METHODS

Randomized prospective study of 3 groups of 20 patients (Group I: thiopentone alone; Group II: ketamine alone; Group III thiopentone and ketamine combination).

RESULTS

Systolic blood pressure (BP) (as measured at baseline, after induction, at intubation, and at 5 min, 10 min, 15 min, 20 min, 25 min, 30 min): baseline BP did not differ significantly across groups. However, postinduction values were significantly higher for Group II (ketamine alone) (P>0.001), but these values normalized by 30 min postinduction. Diastolic BP (as measured at baseline, after induction, at intubation, and at 5 min, 10 min, 15 min, 20 min, 25 min, 30 min): baseline BP did not differ significantly across groups. After induction, diastolic BP increased significantly in all groups. In Group I and Group III, these values returned to baseline after 10 min, and in Group II at the 30 min postinduction stage. Heart rate (measured at the same time as BP): at rest, presented no significant difference in heart rate across groups. At induction, all groups showed a significant rise in heart rate. At intubation, Group I showed an increase in heart rate, Group II a decrease in heart rate, and Group III no change. These intergroup variations were statistically significant. Apgar scores and umbilical venous gas measurements: although there were intergroup variations, these were not statistically significant. Postoperative pain assessment (subjective) VAS scores: the VAS pain scores 3 h after surgery were significantly higher in Group I, both at rest and coughing, at 24 h after surgery the difference persisted for scores at rest, but equalized during coughing. Postoperative pain assessment (objective) time to first analgesic demand: the duration of time to demand for first analgesic was significantly longer in Group II (ketamine only). Postoperative pain assessment (objective) total consumption of analgesic: patients of Group I consumed a significantly higher amount of analgesics than the other groups. Intraoperative event recall, awareness: no patient reported any adverse events of this nature.

CONCLUSIONS

We conclude that though there were no adverse events and a significantly lower analgesic requirement, the use of ketamine alone as an induction agent in Cesarean section should be avoided, as it causes significant maternal hemodynamic changes. The addition of a reduced dose of ketamine to thiopentone in the induction cocktail confers the benefit of reducing analgesic requirement without side effects. The treatment is safe and effective for the mother and child.

Effect of pH on stability of recombinant botulinum serotype A vaccine in aqueous solution and during storage of freeze-dried formulations

The purpose of this study was to evaluate the importance of prelyophilization solution pH on the stability of botulinum neurotoxin, serotype A (rBoNTA(H(c))). This understanding is of significant importance for proteins such as rBoNTA(H(c)), a potential constituent of a multivalent vaccine product. For multivalent vaccines it may be difficult to identify a liquid formulation satisfying the stability requirements for all constituent protein antigens. Consequently, a lyophilized multivalent vaccine formulation may be a more viable alternative. Therefore evaluating the effect of prelyophilization pH (may be suboptimal) on the stability of antigens such as rBoNTA(H(c)) during lyophilization/storage becomes important. We hypothesize that when rBoNTA(H(c)) is lyophilized from a suboptimal pH, using the appropriate stabilizers can provide adequate physicochemical stability during lyophilization and long-term storage. We identified pH 5 and 8 in which the protein was stable and unstable against aggregation. Excipients were identified that could stabilize rBoNTA(H(c)) during lyophilization and storage in a stable solution of pH 5. These excipients were 7.5% (w/v) trehalose and 2.5% (w/v) trehalose with 2.5% (w/v) HES, with and without 0.01% (w/v) polysorbate 20. In support of our hypothesis, these excipients were found to provide adequate physicochemical stability to rBoNTA(H(c)) during lyophilization/storage, when freeze-dried from a prelyophilized solution of pH 8.

The 'Sartorius Switch' and its relevance for the radiologist

We report the case of a 43 year old female patient, who underwent a left groin dissection 5 years after her original diagnosis of a 3.8mm Breslow thickness malignant melanoma of her left leg, where the appearance of a post-operative computed tomography (CT) scan caused diagnostic misunderstanding. This case demonstrates the importance of providing the radiologists with accurate information regarding surgical procedures prior to imaging such that misinterpretations of this kind can be avoided. Whilst the detail of an operation may be obvious to the surgical team, one cannot expect radiologists to be aware of either standard procedural detail, or indeed new surgical developments.

Accelerated dosing frequency of a pulmonary formulation of tissue plasminogen activator is well-tolerated in mice

1. Tissue plasminogen activator (tPA) has both fibrinolytic and anti-inflammatory activity. These properties may be useful in treating inflammatory lung diseases, such as acute respiratory distress syndrome (ARDS). 2. We have previously demonstrated the feasibility of targeted pulmonary delivery of tPA. As part of our research to develop a clinically viable pulmonary formulation of tPA, we assessed the tolerability and incidence of haemorrhage associated with the administration of a pulmonary formulation of mouse tPA (pf-mtPA). 3. Intratracheal doses of nebulized pf-mtPA or sterile saline were administered with increasing frequency to male and female B6C3F1 mice. After dosing, the mice entered a recovery period, after which they were killed and their lungs were lavaged and harvested. Post-mortem gross necropsy was performed and all major organs were assessed histologically for haemorrhage. The bronchoalveolar lavage fluid was assessed for markers of lung injury. 4. Mouse tPA that was formulated to mimic a previously characterized human pf-tPA was well tolerated when given intratracheally with increasing dosing frequency. The administration of pf-mtPA did not result in any detectable haemorrhagic-related events or signs of lung injury. 5. The results of the present longitudinal study demonstrate that a maximally feasible dose of pf-mtPA (3 mg/kg) can be given frequently over a short period of time (12 h) without haemorrhagic complications. Although these data were generated in a healthy mouse model, they provide support for the continued evaluation of pf-tPA for the treatment of pulmonary diseases, such as ARDS.

Effects of solution conditions and surface chemistry on the adsorption of three recombinant botulinum neurotoxin antigens to aluminum salt adjuvants

Botulinum neurotoxin (BoNT) is a biological warfare threat. Protein antigens have been developed against the seven major BoNT serotypes for the development of a recombinant protein vaccine. This study is an evaluation of adsorption profiles for three of the recombinant protein antigens to aluminum salt adjuvants in the development of a trivalent vaccine against BoNT. Adsorption profiles were obtained over a range of protein concentrations. The results document that charge-charge interactions dominate the adsorption of antigen to adjuvant. Optimal conditions for adsorption were determined. However, potency studies and solution stability studies indicated the necessity of using aluminum hydroxide adjuvant at low pH. To improve the adsorption profiles to AlOH adjuvant, phosphate ions were introduced into the adsorption buffers. The resulting change in the adjuvant chemistry led to an improvement of adsorption of the BoNT antigens to aluminum hydroxide adjuvant while maintaining potency. Competitive adsorption profiles were also determined, and showed changes in maximum adsorption from mixed solutions compared to adsorption from individual protein solutions. The adsorption profiles for each protein varied due to differences in adsorption mechanism and affinity for the adjuvant surface. These results emphasize the importance of evaluating competitive adsorption in the development of multivalent vaccine products.

Serial ductal lavage for biomarker assessment in a phase 2 prevention study with tamoxifen

1509

Background: Effective methods of epithelial sampling to measure breast-specific biomarkers will aid the rapid evaluation of new preventive interventions. We report a proof-of-principle Phase 2 study to assess the utility of ductal lavage (DL) to measure biomarkers using tamoxifen (TAM) as the gold standard prevention agent. Methods: We enrolled women with a 5-year Gail risk >1.6 or the unaffected breast of women with breast cancer =1 cm. After entry DL, participants chose TAM or observation (OBS), and underwent repeat DL 6 months later. Samples were processed for cytology and immunohistochemistry for ER and Ki-67 labeling indices (LIs). If =1 duct showed atypia, the sample was called atypical. LI data were analyzed by duct (comparing the same duct at 2 time points) and by woman (comparing the mean of all ducts at 2 time points). Results: Of 168 women recruited, 135 (80%) underwent entry and repeat DL; 82 (49%) had sufficient cells for analysis at both time points (mean age 50 years, mean Gail 3.0). 44 chose observation and 38 chose TAM. Cytologic findings, by woman and by duct, showed significantly greater net improvement (from atypical to benign) in the TAM than in the OBS group (see table ). The repeat ER and Ki-67 LIs showed a significant reduction from entry within the TAM group (p=0.01 and 0.0001, respectively), but not in the OBS group when analysed by duct. Similarly, in analyses by woman, the ER and Ki-67 LIs decreased from entry to repeat DL within the TAM group (p=0.046 and 0.004 respectively), with minimal changes in the observation group. Between-group data are shown in the table and are similar to the within- group differences. Conclusions: Using DL, we saw the expected changes in TAM-related biomarkers, with stronger reductions in duct-to- duct comparisons than when findings were averaged across ducts in individual women. However, the 51% attrition rate of subjects from recruitment to biomarker analyses, along with the expense of DL, raises questions regarding the efficiency of this procedure in biomarker assessment over time.

[Table: see text]

No significant financial relationships to disclose.

Effect of buffer species on the thermally induced aggregation of interferon-tau

It is now becoming apparent that a common pathway of protein aggregation involves the unimolecular structural rearrangement from the native state to a slightly expanded aggregation-competent species. It is the goal of this study to understand the aggregation and the effects of buffer on the stability of IFN-tau. In this study, the thermally-induced aggregation of interferon-tau (IFN-tau) is described. By monitoring the aggregation rate in the presence of increasing amounts of sucrose, the relative change in surface area (Deltas) for conversion to the aggregation-competent state can be determined. Under conditions of pH 7 and in 20 mM buffer, the protein displays different aggregation rates depending on the nature of the buffer species. The protein aggregates mostly quickly in phosphate buffer, slower in the presence of Tris and slowest in the presence of histidine. The largest value for Deltas occurs for the histidine-containing samples, where aggregation proceeds via a slightly expanded aggregation competent state with a surface area increase of 7.6%. Furthermore, it appears that histidine binds to the native state of IFN-tau, thereby stabilizing the native state and retarding aggregation. Measurement of the second virial coefficient, B(22), for different formulations indicates that inclusion of histidine has only a small effect on repulsion between protein molecules, suggesting that colloidal stabilization is not the dominant mechanism for stabilization of IFN-tau. This study represents the first detailed biophysical study of specific buffer-induced stabilization, resulting in shifting the equilibrium towards the native state and away form the expanded aggregation-competent species.

Second virial coefficient determination of a therapeutic peptide by self-interaction chromatography

Self-interaction of macromolecules has been shown to play an important role in a number of physical processes, including crystallization, solubility, viscosity, and aggregation. Peptide self-interaction is not as well studied as for larger proteins, but should play an equally important role. The osmotic second virial coefficient, B, can be used to quantify peptide and protein self-interaction. B values are typically measured using static light scattering (SLS). Peptides, however, do not scatter enough light to allow such measurements. This study describes the first use of self-interaction chromatography (SIC) for the measurement of peptide B values because SIC does not have the molecular size limitations of SLS. In the present work, SIC was used to measure B for enfuvirtide, a 36-amino acid therapeutic peptide, as a function of salt concentration, salt type, and pH. B was found to correlate strongly with solubility and apparent molecular weight. In general, the solubility of enfuvirtide increases with pH from 6 to 10 and decreases as the salt concentration increases from 0 to 0.5M for three different salts. The effect of peptide concentration on B was also investigated and shown to have a significant effect, but only at high concentrations (>80 mg/mL).

Solution behavior of a novel type 1 interferon, interferon-τ

Interferon-tau (IFN-tau) is a novel cytokine that appears during fetal development of mammals. It is currently being investigated for treatment of viral infections and autoimmune diseases. In order to develop a commercial product, a stable formulation will need to be identified. In this study, the solution behavior of IFN-tau was studied using a variety of biophysical methods. The overall structure of IFN-tau is well defined, with the polypeptide chain folding into a four-helix bundle structure, much like other type 1 interferons. However, its solution behavior has not been characterized. The globular structure has a free energy of unfolding of approximately 4 kcal/mole at room temperature. IFN-tau was found to remain monomeric upon increasing the protein concentration, even up to 60 mg/mL. The overall structure of IFN-tau is maintained across a pH range of 2-8, but is significantly altered in the presence of nonaqueous solvents. However, IFN-tau appears to refold efficiently when diluted into an aqueous medium from a nonaqueous solution. This behavior allows the protein to be formulated in low water content formulations suitable for use in capsules.

Feasibility of tissue plasminogen activator formulated for pulmonary delivery

PURPOSE

This study was conducted to assess the feasibility of a pulmonary formulation of tissue plasminogen activator (tPA) for nebulization into the airway by measuring protein stability, biologic activity, particle size, and estimating human lung distribution.

METHODS

Formulations were derived by varying the surfactant and protein concentrations. Protein stability and recovery of each nebulized tPA formulation were assessed by ultraviolet spectroscopy. Formulations that met protein stability feasibility criteria were assessed for biologic and fibrinolytic activities. Biologic activity was determined by their ability to inhibit superoxide anion production by human neutrophils. Fibrinolytic activity was assessed by the cleavage of plasminogen to plasmin. Aerodynamic properties were assessed using a cascade impactor, and an estimation of human airway deposition was made via a human lung replica.

RESULTS

Twenty-seven tPA formulations were initially assessed, 15 of which met protein stability criteria. Subsequently, three of these formulations maintained biologic and fibrinolytic activities. These formulations exhibited particle sizes of 2.4-3.1 microm, and had respirable doses > or =65%. A formulation of 1mg mL(-1) tPA and 0.1% Tween 80 exhibited a 45% deposition in the lower airways of a human lung replica.

CONCLUSIONS

A suitable pulmonary tPA formulation was identified that, following nebulization, maintained protein stability as well as biologic and fibrinolytic activities, and resulted in an optimal respirable dose and human airway deposition. This formulation may be applicable in the treatment of lung diseases, such as acute respiratory distress syndrome by permitting targeted pulmonary delivery of a therapeutic protein to the lungs.

Noninvasive Determination of Protein Conformation in the Solid State Using Near Infrared (NIR) Spectroscopy

Fourier transform infrared (FTIR) spectroscopy is a powerful tool for monitoring structural changes in lyophilized protein formulations. However, direct measurement of IR spectra requires significant handling time and effort. The possibility of using near infrared (NIR) spectroscopy as a rapid and noninvasive alternative to FTIR is explored in this study. NIR and conventional FTIR spectra were collected for two model proteins, alpha-chymotrypsinogen A and cytochrome c, under conditions of varying stability and structural perturbation. NIR was then compared to FTIR and whereby calibration model was generated by partial least square (PLS) regression to correlate NIR data with FTIR spectra. There is a strong correlation of certain NIR bands with the amide I region of FTIR spectra. It appears that NIR can distinguish damage caused by elevated temperatures and freeze-drying stresses. The ability of sucrose to stabilize the structure of these two proteins can be detected by both methods. It appears that NIR spectroscopy has the potential to provide detailed information on the secondary structure of proteins in the solid state. However, many more examples will be needed to demonstrate fully the ability of NIR to replace FTIR as the standard tool for characterizing lyophilized protein formulations.

Perinucleolar compartment prevalence has an independent prognostic value for breast cancer

The perinucleolar compartment (PNC) is a multicomponent nuclear structure enriched with RNAs transcribed by RNA pol III and RNA binding proteins. Studies in cultured cells showed an association between PNC and transformed phenotype. To evaluate the relationship between structure and malignancy in vivo, we examined PNC prevalence (the percentage of cells containing at least one PNC) in normal and cancerous paraffin-embedded breast tissues using immunohistochemistry against a PNC-associated protein. Five hundred nuclei in the most active area of each sample were scored for PNC prevalence. The results show that PNC prevalence significantly correlates with the progression of breast cancer (by the criteria of staging). PNC prevalence in primary tumors, lymph nodes, and distant metastases shows a stepwise increase from a median of 23% in primary tumors to approximately 100% in distant metastases. In addition, univariate and multivariate (controlling for tumor size and grade) analyses show that early-stage patients with invasive ductal carcinomas containing a higher PNC prevalence have a significantly poorer prognosis. These findings link PNC prevalence with the progression of breast cancer in vivo and suggest that PNC-containing cells have metastatic advantages. These findings also show the potential of PNC prevalence as a prognostic marker for breast cancer.

Perinucleolar Compartment Prevalence Has an Independent Prognostic Value for Breast Cancer

The perinucleolar compartment (PNC) is a multicomponent nuclear structure enriched with RNAs transcribed by RNA pol III and RNA binding proteins. Studies in cultured cells showed an association between PNC and transformed phenotype. To evaluate the relationship between structure and malignancy in vivo, we examined PNC prevalence (the percentage of cells containing at least one PNC) in normal and cancerous paraffin-embedded breast tissues using immunohistochemistry against a PNC-associated protein. Five hundred nuclei in the most active area of each sample were scored for PNC prevalence. The results show that PNC prevalence significantly correlates with the progression of breast cancer (by the criteria of staging). PNC prevalence in primary tumors, lymph nodes, and distant metastases shows a stepwise increase from a median of 23% in primary tumors to ∼100% in distant metastases. In addition, univariate and multivariate (controlling for tumor size and grade) analyses show that early-stage patients with invasive ductal carcinomas containing a higher PNC prevalence have a significantly poorer prognosis. These findings link PNC prevalence with the progression of breast cancer in vivo and suggest that PNC-containing cells have metastatic advantages. These findings also show the potential of PNC prevalence as a prognostic marker for breast cancer.

Quantification of glycine crystallinity by near-infrared (NIR) spectroscopy

The object of this investigation was to use near-infrared (NIR) spectroscopy for quantification of glycine crystallinity. Glycine samples, with different degrees of crystallinity, were obtained by physically mixing different proportions of crystalline beta-glycine with amorphous glycine. NIR spectra were obtained, directly from samples in glass vials, over the wavelength range of 1100-2500 nm. A partial least squares (PLS) model was developed to correlate the NIR spectral changes with the degree of crystallinity. Using this model, a standard error of calibration (SEC) of 2.1% was obtained with an r(2) value of 0.996. Cross validation was used to test the precision of the quantitative model, resulting in a standard error of prediction (SEP) of 3.2%. These results indicate that NIR spectroscopy is well suited to the measurement of glycine crystallinity in lyophilized products. Employing the PLS model, the crystallinity of glycine in freeze-dried sucrose-glycine mixtures was evaluated. At a sucrose to glycine ratio >4, glycine crystallization during lyophilization was inhibited. Conversely, at ratios < or =0.67, glycine remained substantially crystalline. At intermediate compositions, the glycine was partially crystalline.

Infrared spectroscopic studies of protein formulations containing glycine

Glycine is extensively used as an excipient in protein formulations. However, it absorbs significant infrared (IR) radiation in the conformationally sensitive amide I region (1700-1600 cm(-1)) of proteins. Furthermore, glycine can form a number of polymorphs, as well as an amorphous phase. Each of these forms possibly exhibits a different IR absorption spectrum. Accurate subtraction of glycine signals, in order to obtain reliable amide I spectra, was found to be possible only if the protein-to-glycine ratio was >/=1:1. In those cases, the solid-state conformation of the protein could be determined. In addition, a new method for estimating the degree of crystallinity of freeze-dried glycine is described, using IR bands in the 1350-1300 cm(-1) region.

A novel method for removing residual acetone from gelatin microspheres

PURPOSE

To develop a method for removing residual acetone from gelatin microspheres.

METHODS

Free-flowing gelatin microspheres were either heated under vacuum or subjected to a stream of humidified air in a specially designed apparatus for removal of the residual acetone. To understand the removal mechanism, hygroscopic and thermal properties of the microspheres were examined.

RESULTS

Heating the gelatin microspheres under vacuum did not reduce the acetone level below 2%, but the use of humidified air under fluidizing condition reduced the residual acetone in gelatin microspheres by an additional two orders of magnitude. The rate of acetone removal was a strong function of the relative humidity (RH) of the air stream; higher RH accelerated acetone removal. Other variables influencing the acetone removal rate are the mean particle diameter and the linear velocity of the humidified air. Under high relative humidities, significant amounts of moisture were absorbed into gelatin microspheres, reducing their glass transition temperature below 25 degrees C.

CONCLUSION

The residual acetone in gelatin microspheres can be efficiently removed when exposed to air of high RH. Mechanisms of water-dependent acetone removal are proposed.

Diagnostic challenges in aspiration cytology of the salivary glands

The main goal of fine-needle aspiration (FNA) of salivary gland lesions is to assist the clinician in the management of patients who present with a mass lesion. Cytologic examination aims to determine, if a process is inflammatory and/or reactive, benign or malignant neoplasm and if possible renders a specific diagnosis. It has been argued that in the area of salivary gland tumors, surgical management relies less heavily on a specific preoperative diagnosis, because almost all neoplastic salivary gland lesions will undergo surgical excision. However, knowing beforehand if a lesion is malignant or benign, will aid in planning surgery and may prompt or postpone decisions for surgical intervention. The salivary glands are unique in their histologic complexity and morphological variability of tumors, which is reflected in the cytologic material. In addition to the overlapping morphologic patterns of salivary gland tumors, they also represent relatively rare lesions, thus making it more difficult to acquire diagnostic expertise in FNA. Other than approaching salivary gland tumors by a description of single entities in their benign and malignant categories, we favor a more practical approach to diagnosis based on the key morphologic features noted in FNAs. This article addresses differential diagnoses according to the predominant cytologic presentation with attention to the cell type and size, nature of the cytoplasm, and the smear background.

Thyroid aspiration cytology: a "cell pattern" approach to interpretation

The key to the interpretation of thyroid fine needle aspiration is largely dependent on the recognition of various morphologic patterns of epithelial cells, usually follicular cells, and background elements, such as colloid. These morphologic patterns consist of 3 parts: 1) The arrangement of cells with respect to one another, 2) The cytologic features of individual cells, and 3) The presence of background elements. The cellular arrangements generally encountered in fine needle aspiration of the thyroid include the follicular patterns (macro-/normo-follicular and micro-follicular), the papillary pattern, the syncytial pattern, the dispersed cell pattern, and the cystic pattern. This article approaches some of the differential diagnostic challenges encountered while interpreting thyroid aspiration cytology by focusing first on the overall cellular arrangement to generate a differential diagnosis and then narrowing that differential by assessing cellular features of individual cells and the presence of background elements.

Adenocarcinoma in colonic brushing cytology: High-grade dysplasia as a diagnostic pitfall

Cytologic evaluation of brushing specimens obtained from the colon may be useful in the diagnosis of neoplastic and inflammatory lesions, as previous studies have reported favorable sensitivity and specificity figures for this procedure. In this study, we report our experience with 80 colonic brushings examined over a 5-yr period. Thirty cases received an atypical or malignant cytologic diagnosis. Nineteen of 20 cases diagnosed cytologically as adenocarcinoma revealed adenocarcinoma on biopsy; one case showed only adenomatous epithelium on biopsy and subsequent resection. Cases diagnosed cytologically as "atypical" or "adenomatous" showed adenocarcinoma, adenoma, and inflammatory conditions upon biopsy. Slides from 30 atypical/malignant cases were retrospectively reviewed for a number of cytomorphologic features and were correlated with the histologic diagnosis. Cases from histologically confirmed adenocarcinoma tended to show greater degrees of altered nuclear polarity, nuclear pleomorphism, membrane irregularities, and chromatin pattern alterations than those from histologically proven adenomatous or inflammatory lesions. The most likely cause of a false-positive diagnosis in this setting is sampling of an adenoma with high-grade dysplasia which fails to meet histologic criteria for adenocarcinoma (invasion of the underlying muscularis mucosae). Thus, in the second part of the study, we examined histologic sections from surgically excised adenomas to determine the frequency with which profound nuclear atypia is at least focally present, potentially resulting in a false-positive cytology diagnosis upon brushing. Slides from 51 cases were reviewed; cytologic atypia beyond that typically observed in adenomas was not observed in 43% of cases. However, profound nuclear atypia was present in 6% of cases; cytologic evaluation of a brushing specimen from these lesions may have resulted in a false-positive diagnosis of adenocarcinoma, despite the histologic diagnosis of adenoma with severe dysplasia. The remaining cases demonstrated intermediate degrees of atypia. These findings serve to quantitate the frequency with which cytohistologic discrepancies might be expected for mass lesions of the colon.

Differences in cell cycle kinetics of candidate engrafting cells in human bone marrow and mobilized peripheral blood

Patients undergoing hematopoietic stem cell transplantation (HSCT) with mobilized peripheral blood (MPB) engraft quicker than those receiving bone marrow (BM). Our objective was to determine whether candidate engrafting cells--primitive hematopoietic progenitors (PHPs)--from MPB and BM exhibit different responses to cytokines that could explain this observation. We compared the cell cycle kinetics and ex vivo expansion of PHP-enriched cells obtained from MPB (n = 12) and BM (n = 10) by fluorescence-activated sorting of CD90+, AC133+ or CD38(dull) subsets of pre-selected CD34(+) cells. Cell cycle status, before and after 40 hours of serum-free culture with a cytokine cocktail, was assessed by multiparameter flow cytometry following incubation with Hoechst 33342 and pyronin Y. We found that 0.2% +/- 0.3% of MPB CD34(+)CD90(+) cells were in S/G(2)/M phases at hour 0, compared with 5% +/- 2.5% of those from BM (p = 0.0001), and 86.3% +/- 9.7% were in G(0), compared with 65.3% +/- 10% of those in BM (p = 0.0001). After 40 hours of culture, CD34(+)CD90(+) cells from MPB were more mitotically active than those from BM, with 29% +/- 4.9% in S/G(2)/M and 20% +/- 11.4% in G(0), compared to 19% +/- 6.5% (p = 0.001) and 39.2% +/- 22% (p = 0.027) of cells from BM. There was greater expansion of both total CD34(+) cells and the CD90(+) subset from MPB samples (p = 0.001 and 0.0001, respectively). Results from PHPs defined on the basis of AC133 expression correlated well with results obtained in CD90(+) subsets (r(2) = 0.81; p = 0.014).MPB PHPs appear to be primed for a greater acceleration in mitotic activity upon cytokine exposure. This qualitative difference may contribute to the earlier engraftment seen after HSCT using MPB grafts.

Replicative stress after allogeneic bone marrow transplantation: changes in cycling of CD34+CD90+ and CD34+CD90- hematopoietic progenitors

To further characterize hematopoietic "replicative stress" induced by bone marrow transplantation (BMT), the cell-cycle status of CD90+/- subsets of marrow CD34+ cells obtained 2 to 6 months after transplantation from 11 fully chimeric recipients was examined. Cycling profiles, derived by flow cytometry after staining with Hoechst 33342 and pyronin Y, were compared with those of 14 healthy marrow donors. Primitive CD34+CD90+ cells represented a smaller proportion of CD34+ cells in recipients (10% +/- 4% versus 19.6% +/- 5.3% in donors; P <.0001) and were more mitotically active, with the proportion of cells in S/G2/M nearly 4-fold higher than in donors (15.6% +/- 3% and 4.4% +/- 1.6%, respectively; P <.0001). By comparison, there was a modest increase in the proportion of CD34+CD90- progenitors in S/G2/M after BMT (10.9% +/- 1% vs 9.6% +/- 2% in donors; P =.04). Replicative stress after BMT is borne predominantly by cells in a diminished CD34+CD90+ population.

Cytologic differential diagnosis of papillary pattern in breast aspirates: correlation with histology

Papillary neoplasms, fibroadenoma, fibrocystic change, low-grade ductal carcinoma, and apocrine carcinoma are among "gray zone" lesions in breast cytology. They often have cellular smears with a papillary or pseudopapillary pattern. To better define cytologic criteria useful in distinguishing these entities, we correlated them with histology. Papanicolaou and giemsa stained smears from 33 aspirates and their corresponding histology were reviewed. Of these, 28 had an initial cytologic diagnosis or suspicion of papillary neoplasm, while five cases were not diagnosed cytologically as papillary but the histologic diagnosis was a papillary neoplasm. Cytologic features evaluated included cellularity, architecture, apocrine/single/columnar cells, nuclear atypia, intranuclear inclusions, calcifications, background, myoepithelial cells, and bipolar, naked nuclei. Discriminating cytologic features grouped by final histologic diagnosis were as follows: Papillary neoplasm (14 cases): Hemorrhagic/cystic background, 3-dimensional papillary clusters, columnar cells, and fibrovascular cores. Myoepithelial cells within clusters and background naked, bipolar nuclei were inconspicuous. Fibroadenoma (4 cases): Two-dimensional branching clusters often with folding, moderate myoepithelial cells in clusters, moderate to numerous background bipolar nuclei, often forming doublets in smear background, cellular stroma. Ductal carcinoma (11 cases): Papillary ductal carcinoma in situ in 5 of 11 cases, cribriform/tubular architecture in 6 of 11. Absence or paucity of myoepithelial within clusters and background bipolar nuclei was noted. Fibrocystic change (4 cases): Two-dimensional clusters, moderate myoepithelial cells within clusters, and moderate bipolar nuclei in the background. The presence and quantity of myoepithelial cells, bipolar naked nuclei in the background, and ductal cell architecture were the only consistently useful cytologic features in distinguishing breast lesions with a papillary pattern. Ann Diagn Pathol 5:34-42, 2001.