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There is little information available on the susceptibility of reptilian saccule hair cells to ototoxin-induced sensory damage. In this study, we report morphological evidence of hair cell recovery and regeneration after damage induced by gentamicin in the saccule of a lizard. We perform morphological analysis using scanning electron microscopy and confocal laser scanning microscopy with actin and calbindin as markers for hair cells and tubulin as a marker for supporting cells. The data were consistent: gentamicin induced damage in the hair cells, and the damage increased with increasing duration of treatment. Initially, the saccule appeared unhealthy. Subsequently, the sensory hair cells became compromised, with fused stereovilli, followed by widespread loss of hair cell bundles from the hair cells. Finally, numerous hair cells were lost. Morphologically, the saccule appeared normal 28days after gentamicin treatment. Using a mitogenic marker, we tested whether or not there is hair cell regeneration following administration of gentamicin. We found evidence of bromodeoxyuridine incorporation first in supporting cell nuclei and subsequently in hair cell nuclei. This indicates that a process of sensory epithelium repair and hair cell regeneration occurred, in both extrastriolar and striolar regions, and that the recovery was due to both the proliferation of supporting cells and, as seems likely, self-repair of hair cell bundles.

Autochthonous transmission of the Chagas disease parasite, Trypanosoma cruzi, was detected in a patient in rural New Orleans, Louisiana. The patient had positive test results from 2 serologic tests and hemoculture. Fifty-six percent of 18 Triatoma sanguisuga collected from the house of the patient were positive for T. cruzi by PCR.

West Nile virus (WNV) was first detected in Louisiana during August of 2001. An outbreak of 204 human cases of neuro-invasive disease (NID) and 25 deaths occurred in 2002. In the 2 years following, lower numbers of human cases were identified (101 NID cases in 2003 and 84 in 2004) but intense localized foci were observed. The incidence of NID has been particularly high in the elderly (65 years and older). The distribution of West Nile cases has consisted of sporadic cases with a few very intense foci. Annually, human cases have occurred from June through December, with a peak number of new cases in August. As compared with other WNV serosurveys conducted in the United States, it appears that the WNV seroprevalence in Louisiana is not elevated.

SEM and CLSM studies were performed on the membranous labyrinth of Lampetra planeri, a threatened species of brook lamprey, spanning from the 1st to the 4th year of ammocoetes larval stages and on the adults. In all the examined stages, the entire membranous labyrinth does not show any morphologic differences, but only a progressive increase in size. SEM and CLSM observations show that the ciliated chamber is lined with numerous unsensorial multiciliated cells. In the early stages, the ciliary bundles were approximately 15 microm long, while in the late stages they reached 30 microm. In the crista sensory area, we observed two populations of hair cells. "Type II" cells are peculiar for this species and show both long stereocilia decreasing in length and a long kinocilium (10-12 microm). Two other types of ciliary bundles have been found on the sensory hair cells of the Macula communis: the first one has both kinocilium and stereocilia about 4-5 microm long; the second shows a long kinocilium (7-10 microm in length) and short stereocilia bundles with a gradual increase in length. In the early stages of development, the three macular areas show few and sparsely distributed hair cells. In the late developmental stages, hair cells become more numerous and densely populated.

The membranous labyrinth of lizard Podarcis sicula contains calcite and aragonite crystals. Saccule, utricle and lagena contain calcite crystals while aragonite crystals are present only in the saccule where they are very abundant. We have recently demonstrated the presence of calbindin D-28K in the organic matrix of lizard P. sicula otoconia. In order to define its localization, since calbindin modulates cellular Ca2+ level, otoconia from utricle and lagena were collected separately from those from saccule and then otoconial proteins were extracted. Immunoblot assay on proteins extracted from the otoconia and confocal laser scanning microscope analyses of otoconia using monoclonal anti-calbindin D-28K antibodies indicated that calbindin D-28K is a protein typical of aragonite crystals.

The aim of this study was to evaluate the influence of three variables--protease inhibitors, stavudine, and the length of combined therapy--on body habitus changes, metabolic effects and bone mineral density in HIV patients treated with highly active antiretroviral therapy (HAART). The onset of possible cardiovascular involvement was considered. Forty HIV patients (29 men and 11 women, mean age 39.13 +/- 7.82 years, range 28-61 years) treated with HAART for 12-43 months were evaluated for fat, lean, bone tissues, immunohematological and cardiovascular alterations. The differences in fat/lean tissues and bone mineral density were evaluated at dual-energy X-ray absorptiometry (DEXA). Serum lipids and the CD4/CD8 T-cell counts were recorded. ECGs were taken every 6 months; color Doppler echocardiography and color Doppler ultrasounds of the carotid vessels were performed in close chronological sequence with the second DEXA. Statistical analyses included: Student's t-test, Wilcoxon test, and single-multiple regression analysis. Thirteen patients presented with fat loss, 7 fat accumulation, and 20 a combined form of both. The changes in the single body districts showed that the decrease in the limb fat is to be attributed to protease inhibitors, while none of the three variables was responsible for the decrease in the upper limb fat. The trunk weight increase was not significant. The decrease in the lean mass of the upper limbs is to be attributed to protease inhibitors, while none of the three variables was responsible for the increase in the lean mass of the upper and lower limbs. The decrease in bone mineral density was not significant. No treatment-related cardiovascular lesions were observed. In HIV patients treated with HAART for 12-43 months, the decrease in lower limb fat was due to protease inhibitors. Neither osteopenia nor cardiovascular diseases were observed during follow-up.

In 2002, 329 cases of West Nile illness were reported in Louisiana, including 204 cases of West Nile meningoencephalitis and 125 cases of West Nile fever. Clinical presentation of meningoencephalitis or of West Nile fever was confirmed serologically. There were 24 deaths. Age group distribution showed predominance among persons aged 45 years or older. The epidemic curve, based on date of diagnosis, showed numerous foci progressing in successive waves. The first cases occurred in mid-June. A peak was reached by the first week of August, after which the epidemic progressively subsided.

The factors controlling otoconia growth are not well known but it seems that the type of proteins contained in the otoconia regulates the initiation and/or the subsequent rates of crystal growth determining the morphology and the size of the final crystal. In order to clarify the mechanism of otoconia formation and their turnover, major proteins contained in the otoconia from the maculae of the saccule, utricle and lagena of inner ear of lizard Podarcis sicula were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Coomassie staining of SDS-PAGE resulted in a major broad band of 15 kDa and four other bands of 21, 28, 45 and 97 kDa. The proteins of 15, 21, 28 and 45 kDa were separated by high-pressure liquid chromatography on a C-4-reverse-phase column and the incubation of blots with monoclonal anti-Calbindin D28K antibodies indicated that the band of 28 kDa was Calbindin D28K, a calcium-binding protein.

We studied hair cell regeneration in the crista ampullaris of the lizard Podarcis sicula both in untreated animals and at early and late time intervals following a single high dose of gentamicin. The study was carried out using the S-phase marker 5-bromo-2'-deoxyuridine. Our ultrastructural and immunofluorescence studies showed that both apoptosis and hair cell regeneration happen in the lizard crista ampullaris in untreated animals, and that regenerative processes are greatly accelerated after treatment with the aminoglycoside antibiotic gentamicin. Our observations indicate that hair cell regeneration is strongly implicated in the repair of damaged sensory epithelium, and that new hair cells appear likely to arise from supporting cells.

The authors studied the otoliths of the Nototheniid Trematomus bernacchii with scanning electron microscopy and X-ray diffraction analysis. Results obtained reveal that three otoliths are present: a large sagitta, a lapillus and a fragile asteriscus. Their sensorial faces appear finely decorated as shown by scanning electron microscopy (SEM). The sagitta and the lapillus are aragonitic while the asteriscus is vateritic, as demonstrated by X-ray diffraction.

In order to clarify the occurrence, distribution and possible role of apoptosis during inner ear development, the ultrastructural aspects (by TEM) (at 9-19 incubation day and 1 day after hatching) and the distribution of the apoptotic phenomenon (by the TdT-mediated dUTP nick end-labeling technique), were studied in the crista ampullaris of chick embryo at 5-19 days of incubation to hatching and of postnatal 1-day old chick. We found, in the sensorial epithelium, dark supporting cells in chick embryos and mainly dark hair cells in postnatal chicks, both with ultrastructural features consistent with those of apoptosis. The presence of apoptotic phenomena was confirmed by the TUNEL technique. According to our findings, it is hypothesized that apoptosis in the inner ear may be involved: 1) at first, in macroscopic remodelling of the membranous labyrinth in early developmental stages, 2) later, in the correct differentiation of the hair and of the supporting cells, leading to characteristic cellular pattern formation and 3) finally, in physiological cell turnover of the postnatal chicken sensorial epithelium of the crista.

Background: Follicular lesions represent a gray area of interpretation in fine needle aspiration biopsy (FNAB) of the thyroid, with as much as 25% inconclusive reports. We identified "predominantly follicular lesions" (PFLs) as the cytologic category most apt to take advantage of planimetric analysis to reach a more definitive diagnosis., Study Design: Sixty-eight cases of FNAB were diagnosed as PFL among the 1,296 FNABs submitted to our institution between January 1994 and June 1995. These cases underwent planimetric analysis with a Leica semiautomatic image analyzer. A smear from a colloid nodule was used as a reference slide. Nuclear areas, perimeters, form factors and maximum diameters were evaluated. Cases in which nuclear areas and maximum nuclear diameters values were found to be > or = 30% higher than the corresponding values found in the reference slide were reported to the clinician as suspicious for malignancy ("flagged" by the computer). These cases required closer follow-up with repeat FNAB within a month, ultrasound and nuclear imaging studies. Nineteen of these cases underwent surgical resection., Results: Histologic reports diagnosed 9 cases of follicular carcinomas, 4 cases of follicular adenomas and 6 cases of nodular hyperplasia. When nuclear areas, perimeters and maximum diameters were all utilized, all the malignant lesions were reported correctly by the computer analysis as flagged, and all the benign lesions were reported as "not flagged." The sensitivity and specificity were 100%, and statistically significant correlations were proven., Conclusion: Although the above data provide strong evidence for the value of planimetric analysis in differentiating between follicular lesions, we cannot reach definitive conclusions on the basis of such a limited number of cases. However, the results stimulated our current efforts in applying planimetry along with the evaluation of other biologic markers to a larger set of cases.

Purpose of Investigation: The purpose of this study was to evaluate treatment by cold-knife-conization in women carriers of cervical intraepithelial neoplasia (CIN)., Methods: The histologic findings of pre-clinical neoplasia of the cervix after conization were compared to the previous findings of cytology, colposcopy and punch-biopsy in 110 women examined between 1985 and 1995. The chi square test (chi2) was used for the statistical analysis., Results and Conclusions: A close correlation is clinically important where complementary roles of these three methods are used to identify lesions suitable for local ablative therapy. The Pap test alone is no longer sufficient for the screening of the pre-cancerous lesion of the cervix and colposcopy is compulsory each time the smear is inadequate or altered. Conization permitted us to single out 13 (11.8%) cases of carcinoma. After cold-knife conization we had six (5.4%) recurrences within two years and two (1.8%) within three years. Our data show that conservative therapy by conization in women with CIN reduces the risk of invasive cancer of the cervix but careful follow-up of these patients is essential.

The purpose of our study was to examine the concordance among colposcopy, cytology, and histology in the diagnoses of intraepithelial lesions of the uterine cervix. We compared the results of Pap tests, biopsies, and colposcopy in 190 patients, who had histologically proven CIN and/or HPV infection, using histology as "the gold standard". The chi 2 (chi square) test was used for the statistics analysis. The sensitivity of cytology for the detection of CIN was 70%, and was lower for LGL (low grade lesions) than for HGL (high grade lesions): 61.2% versus 88.5%, respectively (p < 0.0001). We obtained a high rate of false negative smears (30%), with a relatively high rate of inadequate samples (59.6%). The sensitivity of colposcopy was 92%. Our results suggest that the Pap test alone is no longer sufficient for the screening of precancerous lesions of the cervix, and colposcopy is compulsory each time the smear is inadequate or altered.

According to the modern definition of biocompatibility, a biocompatible material need not be inert but be bioactive. A benign reactivity implies that the reactivity has to be appropriate for the intended use. Chitosan, a non-acetylated or partially deacetylated chitin (a linear homopolymer of beta (1-4)-linked N-acetylglucosamine) has been proposed as a biomaterial because of its apparent satisfactory biocompatibility. The present investigation demonstrates that chitosan has an in vitro stimulatory effect on both macrophage nitric oxide (NO) production and chemotaxis. The macrophage NO secretion is attributed to the N-acetylglucosamine unit of the chitosan molecule rather than to the glucosamine residue (28 and 15 microM NO respectively). Moreover, the immune stimulatory effect of chitosan was very specific since other glycosaminoglycans, such as N-acetyl-D-mannosamine and N-acetyl-D-galactosamine, had no effects on NO production (5 and 8 respectively). In vivo experiments strengthen this hypothesis. Transmission electron microscopy analysis identifies the presence of many leucocytes in the specimens after 14 d post-implantation, showing poor healing processes (i.e. fibroblast proliferation and collagen deposition) that characterize the tissue repair at this time in our animal model.

An immunocytochemical study was carried out with the aim to localize carbonic anhydrase isozymes (CA I and CA II) in the chick membranous labyrinth. CA I and CA II were localized in the same cells and, during the early developmental stages, were diffusely present in the labyrinthine epithelium. At later stages, the sensorial epithelium of the maculae acusticae, crista ampullaris and papilla basilaris, as well as labyrinthine dark cells and the epithelium of the endolymphatic sac strongly stained by the immunocytochemical procedure. In 1-day and 1-week old chicks, CA was present in the same sites as at advanced embryonal stages. In order to detect mRNA for carbonic anhydrase II, in situ hybridization was also used. Strong hybridization signals were observed in the sensorial epithelium of the saccule, utricle and crista ampullaris, in the tegmentum vasculosum, the endolymphatic sac, the erythrocytes and the choroid plexus in embryos older than 10 days. This positivity persisted until the day after hatching. The authors discuss the significance of labyrinthine CA and, based on in situ hybridization results, suggest that melanocytes do not provide labyrinthine dark cells with enzyme protein.

An unusual case of Primary Carcinoma of the vagina was recently observed. The patient was treated surgically in 1981 for squamous cervical carcinoma in situ (CIN 3); eight years later the same patient was treated for squamous carcinoma of the vagina that involved the upper, median and lower tract. She was treated with radical colpectomy and VBP chemotherapy for three courses. The pathology, natural history and treatment are discussed.

The otoconia of Amphibia, especially of the frog Rana esculenta, were studied by X-ray diffraction and scanning electron microscopy (SEM). The SEM studies showed that the membranous labyrinth of Amphibia contains two populations of crystals, which can easily be distinguished by their forms. The X-ray diffraction data indicated that these two populations consist of calcite and aragonite; the endolymphatic sac, the saccule and the lagena contain aragonite, whereas calcite is only found in the otolithic membrane of the utricle. The genetic and functional significance of the existence of two crystalline forms of calcium carbonate in the membranous labyrinth are discussed.

The otoliths of embryos and young animals of the lizard Podarcis s. sicula were studied by X-ray diffraction and scanning electron microscopy. Two types of crystal that give different X-ray diffraction patterns were found in the membranous labyrinth of Podarcis. The crystals consist of calcite or aragonite and are easily distinguished by scanning electron microscopy because of their different morphology. The two calcium carbonate crystal forms are not mixed at random but are present in the embryo from the very beginning in specific sites. The endolymphatic sac contains aragonite crystals while the saccule contains calcite crystals adjacent to the wall, in addition to a preponderance of aragonite crystals. The utricle and lagena contain only calcite crystals. The presence of two crystal forms of calcium carbonate in the membranous labyrinth are discussed in terms of differing genetic and functional significance.

Selected aspects pertaining to the cause and pathogenesis of diskospondylitis were investigated in a kennel of 45 Airedale Terriers. Diskospondylitis was detected via spinal radiography in 17 male and 14 female dogs. Bacteria isolated from the coat, vagina, and urine of affected Airedales were not statistically different from those isolated from clinically normal Airedales. Serologic evidence of Brucella canis infection was not detected. There was no difference in response to thyrotropin stimulation tests between affected and clinically normal dogs. Necropsy findings in affected dogs included hypercellular renal glomeruli and pulmonary arterial thrombi.