Discrete vector solitons in two-dimensional nonlinear waveguide arrays: solutions, stability, and dynamics.

We identify and investigate bimodal (vector) solitons in models of square-lattice arrays of nonlinear optical waveguides. These vector self-localized states are, in fact, self-induced channels in a nonlinear photonic-crystal matrix. Such two-dimensional discrete vector solitons are possible in waveguide arrays in which each element carries two light beams that are either orthogonally polarized or have different carrier wavelengths. Estimates of the physical parameters necessary to support such soliton solutions in waveguide arrays are given. Using Newton relaxation methods, we obtain stationary vector-soliton solutions, and examine their stability through the computation of linearized eigenvalues for small perturbations. Our results may also be applicable to other systems such as two-component Bose-Einstein condensates trapped in a two-dimensional optical lattice.

The detection of endocervical gland involvement by high grade squamous intraepithelial lesions in smears prepared from endocervical brush specimens.

The cytologic features of squamous cell carcinoma in situ with endocervical gland involvement have been described in cervical smears. We evaluated the presence of two types of cellular fragments in 43 cervical smears of high grade squamous intraepithelial lesions (HGSIL) to assess their ability to predict glandular involvement by HGSIL in subsequent cone biopsies. An endocervical brush was used to obtain all endocervical specimens. Of 16 cases without glandular involvement, fragments were present in 13 smears. Of 27 cases with glandular involvement, fragments were absent in 11 smears. No statistical association was identified between the presence of abnormal cellular fragments on cervical smears of HGSIL and endocervical gland involvement on cone biopsies.

Expression of estrogen and progesterone receptors in cytologic specimens using various fixatives.

Estrogen and progesterone receptor reactivity may be useful in identifying possible primary sites of metastatic disease or directing therapy in tumors of the female genital tract, including breast, ovary, and endometrium. Various methods have been described for the immunocytochemical evaluation of estrogen receptor (ER) and progesterone receptor (PR) status of cytologic specimens but our results have been variable. We evaluated the effectiveness of various fixatives [cytospin collection fluid, Shandon, Pittsburgh, PA (SH); ethanol (ETH); and formalin (FOR)] for fixation of smears (SM) and cell block (CB) material. The percentage and intensity of tumor nuclei of SM, CB, and tissue sections (TS) stained for ER and PR by the avidin-biotin-peroxidase complex technique were compared. Samples were considered ER or PR positive when > or = 20% of tumor nuclei were stained. The sensitivity of ER analysis of SMs and CBs in each fixative compared to formalin-fixed paraffin-embedded tissue sections were as follows: SM (SH) 88%, SM (ETH) 14%, CB (SH) 58%, CB (ETH) 43%, and CB (FOR) 70%. The sensitivity of PR determination on SMs and CBs was SM (SH) 71%, SM (ETH) 6.0%, CB (SH) 25%, CB (ETH) 33%, CB (FOR) 80%. These findings indicate that of the fixatives evaluated for ER analysis, SMs fixed in SH provided the best results. For PR evaluation, CBs fixed in FOR gave the best results.

Predictors of human papilloma virus in patients with keratinization.

Given the prevalence of human papilloma virus (HPV) infection, an attempt was made to determine whether certain factors such as keratinization and/or squamous atypia are associated with its development. Review of our gynecologic cytology files from 1989 yielded 1,615 specimens showing parakeratosis and/or hyperkeratosis, without cytologic evidence of HPV. Concomitant diagnoses included no atypia [keratinization only (KO)], inflammatory squamous atypia (ISA), and squamous atypia (SA). Morphologic follow-up including repeat cytology or biopsy was available for 916 cases, 92 (10.0%) of which possessed changes of HPV. For any case with both cytologic and biopsy evidence of HPV, only the biopsy result was tabulated. HPV on follow-up examination was detected in 52 (6.7%) of the 764 cases with KO; in 20 (20.8%) of the 96 cases with keratinization and ISA (KISA); and in 20 (35.7%) of the 56 cases with keratinization and SA (KSA). The definitive diagnosis of HPV was based on previously described features (Gupta, In: Comprehensive Cytopathology, Philadelphia: WB Saunders, 1991:133-140) including nuclear enlargement with nuclear membrane irregularities in combination with sharply demarcated paranuclear cytoplasmic clearing. Affected cells have rounded borders. Binucleated cells are not uncommon. The increasing percentage of HPV from KO to KISA to KSA is not necessarily surprising. However, mathematical analysis revealed statistically significant differences in the development of HPV in each of the 3 groups: KISA vs. KO (P < 0.001), KSA vs. KO (P < 0.001), and KSA vs. KISA (P < 0.05). Therefore, a cytologic diagnosis of keratinization with ISA or especially SA should warrant closer follow-up than that of KO.

Small cell neuroendocrine carcinoma of the endometrium.

Ten cases of endometrial small cell neuroendocrine carcinoma are described. The ages of the patients ranged from 50 to 75 years (mean, 64 years). Most of the tumors were bulky, intraluminal masses that invaded at least half of the myometrial wall. Small cells were the only malignant element in two tumors. In the other eight, there were admixed elements of adenocarcinoma (five), adenosquamous carcinoma (two), or heterologous mesodermal mixed tumor (one). Histologic examination of metastatic deposits in six cases revealed solely small cells in all but one. Immunohistochemical evidence of neuroendocrine differentiation was demonstrated in all tumors using the markers chromogranin, synaptophysin, leu-7, or neuron-specific enolase. Six of these tumors were originally interpreted as mesodermal mixed tumors with a homologous, stromal-type sarcomatous component at initial pathologic examination, but were reclassified as carcinoma. Clinical follow-up of these 10 patients and an additional seven well-documented patients reported in the literature provided strong evidence for the aggressive nature of this neoplasm. Endometrial small cell neuroendocrine carcinoma is a rare, but aggressive neoplasm that can commonly be mistaken for a homologous-type mesodermal mixed tumor.

Immunohistochemical evaluation of myeloid leukemia infiltrates (granulocytic sarcomas) in formaldehyde-fixed, paraffin-embedded tissue.

Paraffin sections of granulocytic sarcomas (GS) (n = 30) were immunohistochemically evaluated for CD3, CD15 (LeuM1), CD20 (L26), CD31, CD34, CD43, CD45, CD68 (KP1), lysozyme, myeloperoxidase (BM1), CD45RO (UCHL1), and LN5 with an avidin-biotin amplification system and a peroxidase-based color development system with DAB as a chromogen. CD45 positivity was present in all lymphomas and 24 of 25 granulocytic sarcomas. Lysozyme and CD43 labeled 26 of 29 granulocytic sarcomas, showing intense cytoplasmic staining. LN5 (membrane-staining) and CD68 (subtle cytoplasmic caplike staining) were found in 20 of 30 cases, often only focally. BM1 and CD15 mainly labeled maturing granulocytes and mostly were negative in primitive myeloid cells. Myeloid progenitor cell antigens CD31 and CD34 were seen in 7 and 12 of 30 cases, respectively. They seemed to recognize different subsets of myeloid leukemia infiltrates (16 cases positive for at least one); the use of CD31 and CD34 for defining these subsets should be evaluated further. Features suggesting a dual phenotype--T-cell and myeloid (positive for CD3, CD68, and lysozyme)--were documented in two cases. In contrast, lymphoblastic lymphomas (n = 4) were positive for CD3 and CD43 but negative for CD68, lysozyme, CD31, CD34, LN5, and myeloperoxidase. Lymphocytic lymphomas (n = 10) were positive for CD20 and CD43 but negative for all other markers. Small, round-cell tumors (n = 15) were negative for all markers. If T-cell and B-cell differentiation can be excluded with other markers, CD43+ is a sensitive marker for myeloid differentiation. Our results show that several markers are useful in the identification of myeloid leukemia infiltrates and in distinguishing them from lymphoblastic and lymphocytic lymphomas and small round-cell tumors in formaldehyde-fixed, paraffin-embedded tissue.

Evaluation of serum immunoglobulins by protein electrophoresis and rate nephelometry before and after therapeutic plasma exchange.

One hundred fourteen pre- and postplasma exchange (PE) serum protein electrophoretograms and serum IgG, IgA, and IgM levels obtained during a 4-month period from 23 patients were evaluated. The interval between PE sessions varied from once daily to approximately once monthly. Typically, post-PE patterns had decreased alpha-1, decreased alpha-2, decreased beta, and decreased gamma fractions. The average percentage decreases of the immunoglobulins subsequent to PE were as follows: IgG, 52%; IgA, 55%; and IgM, 51%. There was a high linear correlation between the pre- and post-PE concentrations of IgG and IgA, whereas correlation of pre- and post-PE IgM concentrations was much lower. All IgG, IgA, and IgM levels (100%) returned to their respective reference intervals before subsequent PE when procedures were scheduled at least 2 weeks apart. When procedures occurred 1 week apart or less, only 1 IgG level (1%) returned to its reference interval, whereas 68 IgA (73%) and 74 IgM levels (80%) returned to their respective reference intervals. During this study, a faint monoclonal band was discovered in each of two patients. One had a normal baseline serum protein electrophoretogram before initiation of PE therapy, and the gammopathy was of uncertain significance. In the other patient, a vertebral plasmacytoma was discovered. It is concluded that PE reduces IgG, IgA, and IgM by approximately the same percentages; however, reference interval levels of IgA and IgM are restored more rapidly than IgG levels. Because monoclonal proteins may be present before or may appear during PE therapy, patients should be monitored by baseline and subsequent periodic serum protein electrophoresis.