Bovine Serum Albumin Binding and Drug Delivery Studies with PVA-Ferrofluid

This paper describes a single-step method for the biomimetic synthesis of stably suspended magnetite nanoparticles in poly(vinyl alcohol) termed ferrofluids. The challenge is to synthesize water based stable magnetic colloids with a control over the particle size and morphology for biomedical applications. The polymer possibly plays a dual role of a surfactant and a functionalizing agent. Transmission electron microscopy, infrared spectroscopy and vibrating sample magnetometry were used to investigate the properties of the synthesized ferrofluids. It has a strong affinity towards the tryptophan residues in bovine serum albumin protein as determined from the fluorescence emission studies. For in vivo applications this could indirectly mean a resistance to immune response and thus ensure long-term circulation. The ability of the synthesized ferrofluid to bind a che-motherapeutic drug ceftriaxone and its ionic release was observed. The polymer hydroxyl group allows drug-binding and the magnetic property allows targeting to specific sites. Magnetic hybrid fluids with combined advantages of magnetism and polymer open up new perspectives for applications.     

Cytologic features of granulosa cell tumors in fluids and fine needle aspiration specimens

OBJECTIVE: To describe the cytologic features of granulosa cell tumors in fluids and fine needle aspiration specimens, with histologic confirmation. STUDY DESIGN: Histologically confirmed granulosa cell tumors, 6 adult type and 1 juvenile type, were identified. All patients had local recurrences or metastases. Eleven specimens from 7 patients, including cytologic samples, cell blocks and histology, were reviewed. Inhibin immunostaining was performed on cell blocks to aid identification of this group of tumors in the cytologic and histologic samples. RESULTS: The patients were 22-72 years old. Sites included ovary and peritoneum; there were pelvic recurrences and metastatic lesions in the spleen, liver, perirectum and cervical lymph node. Cytologic features of adult granulosa cell tumors included 3-dimensional clusters, resettes loose monolayers and individual cells. Other features were Call-Exner bodies, vacuolated cytoplasm, exuberant capillaries associated with papillarylike fronds, a second population of elongated theca cells, and prominent or rare nuclear grooves. In juvenile granulosa cell tumor the features observed were monolayers, loosely cohesive sheets, single cells, occasional larger pleomorphic cells with nuclear clefting and nuclear protrusions, vacuolated cytoplasm, finely granular chromatin and frequent mitoses. The overall cytologic and histologic correlation was good. Inhibin was focally positive in one peritoneal fluid, correlating with the focal pattern of staining seen on histology. CONCLUSION: A definitive cytologic diagnosis of granulosa cell tumor can be made based on the above criteria. Aggressive tumors are discohesive and show pleomorphism and nuclear protrusions. Inhibin stain may be helpful in identifying granulosa cell tumors in cell block specimens.     

Reclassification of "atypical" diagnoses in endoscopic retrograde cholangiopancreaticography-guided biliary brushings

OBJECTIVE: To evaluate the usefulness of reclassifying "atypical" diagnoses in reporting biliary cytology using strict morphologic criteria. STUDY DESIGN: Cytologic specimens from 139 patients (direct, alcohol-fixed smears or cytocentrifuge preparations) were evaluated. Diagnoses were benign (70), atypical (36) and malignant (33). Using strict criteria--major (nuclear contour, chromatin pattern) and minor (polarity, cell types, nuclear size, nuclear grooves, nucleoli, mitosis, nuclear/cytoplasmic [N/C] ratio)--atypical cases were reevaluated and reclassified. Follow-up (F/U) was available on all cases. RESULTS: Atypical cases, (36) were reclassified as malignant (26), atypical favor benign (2)/reactive (3) and atypical, not otherwise specified (NOS) (5). Cases reclassified as malignant showed irregular nuclear contours, chromatin irregularities and rare mitosis. Nuclear enlargement, nucleoli and cellularity varied widely in all groups. N/C ratio was increased in most reclassified malignant cases. All 26 malignant reclassifications correlated with F/U of malignancy. Benign and reactive cases (5) were negative for malignancy on F/U (4), and in 1 case a metastatic carcinoma involving the biliary tree was found. In the 5 atypical (NOS) cases, F/U showed malignancy (3) and pancreatitis (2). Cytocentrifuge preparations made in our laboratory were of superior quality when compared to other methods of cell preparation. CONCLUSION: Irregularities in nuclear membrane and abnormal chromatin pattern were the most consistently useful features correlating with malignancy. The sensitivity and specificity of biliary brush cytology can be enhanced by using strict cytomorphologic criteria and proper collection and fixation, all of which decrease atypical diagnoses.     

Accumulation of peribronchial mast cells in a mouse model of ovalbumin allergen induced chronic airway inflammation: modulation by immunostimulatory DNA sequences

Few peribronchial mast cells are noted either in the lungs of naive mice or in the lungs of OVA-sensitized mice challenged acutely with OVA by inhalation. In this study, we demonstrate that OVA-sensitized mice exposed to repetitive OVA inhalation for 1-6 mo have a significant accumulation of peribronchial mast cells. This accumulation of peribronchial mast cells is associated with increased expression of the Th2 cell-derived mast cell growth factors, including IL-4 and IL-9, but not with the non-Th2 cell-derived mast cell growth factor, stem cell factor. Pretreating mice with immunostimulatory sequences (ISS) of DNA containing a CpG motif significantly inhibited the accumulation of peribronchial mast cells and the expression of IL-4 and IL-9. To determine whether mast cells express Toll-like receptor-9 (TLR-9; the receptor for ISS), TLR-9 expression by mouse bone marrow-derived mast cells (MBMMCs) was assessed by RT-PCR. MBMMCs strongly expressed TLR-9 and bound rhodamine-labeled ISS. However, incubation of MBMMCs with ISS in vitro neither inhibited MBMMC proliferation nor inhibited Ag/IgE-mediated MBMMC degranulation, but they did induce IL-6. Overall these studies demonstrate that mice exposed to repetitive OVA challenge, but not acute OVA challenge, have an accumulation of peribronchial mast cells and express increased levels of mast cell growth factors in the lung. Although mast cells express TLR-9, ISS does not directly inhibit mast cell proliferation in vitro, suggesting that ISS inhibits accumulation of peribronchial mast cells in vivo by indirect mechanism(s), which include inhibiting the lung expression of Th2 cell-derived mast cell growth factors.     

Race and the Culture of Anthropology

The number of panels on "multiculturalism" and "cultural studies" at the AAA's annual meetings has increased significantly. Many anthropologists believe that the discipline has been in the vanguard of debates on racism and multiculturalism, that it stands for precisely those issues raised in the "culture wars": the equal valuation of all cultures. Yet this is not the case.
Multiculturalism and cultural studies have emerged as counterdisciplinary formations which radically foreground race and racial identity precisely because anthropology cannot do so.     

Oscillating behavior of carbohydrate granule formation and dinitrogen fixation in the cyanobacterium Cyanothece sp. strain ATCC 51142.

It has been shown that some aerobic, unicellular, diazotrophic cyanobacteria temporally separate photosynthetic O2 evolution and oxygen-sensitive N2 fixation. Cyanothece sp. ATCC strain 51142 is an aerobic, unicellular, diazotrophic cyanobacterium that fixes N2 during discrete periods of its cell cycle. When the bacteria are maintained under diurnal light-dark cycles, N2 fixation occurs in the dark. Similar cycling is observed in continuous light, implicating a circadian rhythm. Under N2-fixing conditions, large inclusion granules form between the thylakoid membranes. Maximum granulation, as observed by electron microscopy, occurs before the onset of N2 fixation, and the granules decrease in number during the period of N2 fixation. The granules can be purified from cell homogenates by differential centrifugation. Biochemical analyses of the granules indicate that these structures are primarily carbohydrate, with some protein. Further analyses of the carbohydrate have shown that it is a glucose polymer with some characteristics of glycogen. It is proposed that N2 fixation is driven by energy and reducing power stored in these inclusion granules. Cyanothece sp. strain ATCC 51142 represents an excellent experimental organism for the study of the protective mechanisms of nitrogenase, metabolic events in cyanobacteria under normal and stress conditions, the partitioning of resources between growth and storage, and biological rhythms.     

New records of Rotifera from India

Fifteen species of monogonont Rotifera are recorded from India for the first time. These are Lecane acanthinula (Hauer), L. aspasia Myers, L. monostyla (Daday), L. ruttneri (Hauer), L. simonneae Segers, Lepadella costatoides Segers, L. cf. favorita Klement, L. minuta (Montet), L. triba Myers, Notommata pachyura (Gosse), N. saccigera Ehrenberg, Sinantherina semibullata (Thorpe), Trichocerca chattoni (De Beauchamp), T. kostei Segers and Taphrocampa selenura (Gosse). Taxonomic and/or zoogeographic notes are added, when appropriate.     

Degradation of Alpha-, Beta-, and Gamma-Hexachlorocyclohexane by a Soil Bacterium under Aerobic Conditions

A Pseudomonas sp., isolated from sugarcane rhizosphere soil, readily metabolized not only alpha and gamma isomers of hexachlorocyclohexane, but also the thermodynamically more stable beta isomer, under aerobic conditions. Bacterial degradation of the three isomers led to the accumulation of a transitory metabolite and eventual release of covalently linked chlorine as chloride in stoichiometric amounts.     

Epizootiology of Plasmodium hermani in Florida: chronicity of experimental infections in domestic turkeys and northern bobwhites

A pen-reared northern bobwhite and a domestic turkey were infected with a strain of Plasmodium hermani obtained originally from a wild turkey in southern Florida. Blood films from these 2 birds were positive microscopically for 188 and 370 days postinfection (PI), respectively. Culicine mosquitoes (Culex nigripalpus and C. salinarius) were blood fed on the bobwhite and the turkey at different times during the infection and used to transmit the malaria to other bobwhites and turkeys up to days 298 and 473 PI, respectively. It was concluded that in nature, P. hermani could remain in a chronic phase in avian hosts for a year, or longer, allowing survival of the parasite between seasons of mosquito transmission.