Susceptibility to form-deprivation myopia in chicks is not altered by an early experience of axial myopia.

PURPOSE: Studies in humans and primates suggest that early visual experience may influence eye growth and refractive development later in life. In this study, we asked whether experimentally-induced myopia in 1-week-old chicks influences the responsiveness to form deprivation at a later age (4 weeks old). METHODS: A group of White Leghorn chicks ("twice deprived," N = 12) were monocularly deprived of form vision with white translucent diffusers at 3 days of age for 4 days. The diffusers were then removed, and the chicks were allowed 3 weeks of normal vision to age 27 days before being deprived again for 4 days. Another group of chicks ("once deprived," N = 9) were monocularly deprived of form vision at age 27 days for 4 days. Refractive errors, corneal curvatures, and axial ocular dimensions were measured by retinoscopy, infrared videokeratometry, and A-scan ultrasonography, respectively. Measurements were performed daily during the periods of deprivation and at approximately 3-day intervals in between treatments and after the final treatment period. RESULTS: The magnitude of the form-deprivation myopia induced by 4 days of deprivation at 27 days of age was significantly smaller than that induced by the same treatment at 3 days of age (-4.1 vs. -9.8 D; paired t-test, p < 0.01). This difference in induced myopia reflects optical scaling with increasing eye size because the deprivation-induced changes in vitreous chamber depth were not significantly different for the two deprivation periods (0.37 vs. 0.35 mm, paired t-test, p = 0.65). The induction of myopia at the younger age did not affect the susceptibility to form-deprivation myopia at the older age; there was no difference in the response to form deprivation at the older age between the once-deprived and twice-deprived groups (-3.5 vs. -4.1 D; unpaired t-test, p = 0.50). There was also a significant correlation between the amount of axial elongation induced in individual eyes during the first and second periods of deprivation (r = 0.631, p < 0.05). CONCLUSIONS: The induction of form-deprivation myopia at a young age does not affect the response to form deprivation at a later age. The significant correlation between the axial elongation induced in individual eyes over the two successive periods of deprivation suggests individual differences, possibly genetic in origin, in the susceptibility to form-deprivation myopia in chicks.     

The utility of p16INK4a and Ki-67 staining on cell blocks prepared from residual thin-layer cervicovaginal material

BACKGROUND: Cell blocks can be prepared from residual thin-layer cervicovaginal (ThinPrep) material and can be used in immunohistochemical staining assays for p16INK4a and Ki-67, which are surrogate markers related to human papillomavirus infection and cell proliferation, respectively. The objectives of the current study were 1) to investigate the feasibility and the role of cell block preparations in identifying significant neoplastic and preneoplastic lesions of the uterine cervix and 2) to assess the feasibility of using p16INK4a and Ki-67 immunohistochemical staining patterns on cell blocks to identify significant preneoplastic cervical lesions. METHODS: Cervicovaginal cytology specimens from 85 patients were analyzed. Cytologic diagnoses based on ThinPrep Papanicolaou test results were as follows: squamous cell carcinoma was diagnosed in 3 specimens, high-grade squamous intraepithelial lesions (HSIL) were diagnosed in 27 specimens, low-grade squamous intraepithelial lesions (LSIL) were diagnosed in 20 specimens, and atypical squamous cells of uncertain significance (ASCUS) were diagnosed in 11 specimens. Diagnoses of negativity for intraepithelial lesions or malignancy (NILM) were made in 24 specimens. Cell block sections were stained with hematoxylin and eosin and were immunostained with antibodies against p16INK4a protein and Ki-67 antigen. RESULTS: The cytomorphologic diagnoses made using cell block preparations were as follows: SCC in 2 specimens, HSIL in 20 specimens, LSIL in 30 specimens, NILM in 32 specimens, and no diagnosis in 1 specimen. In 62 cases (73%), the diagnoses made using cell block preparations were in agreement with the ThinPrep diagnoses. Immunostaining of cell blocks for p16INK4a and Ki-67 exhibited a statistically significant association (P < 0.05) with the presence of significant lesions on either cell block or ThinPrep analysis. CONCLUSIONS: To the authors' knowledge, p16INK4a has not been analyzed previously in ThinPrep cell blocks, and the correlation between Ki-67 expression and cell block diagnoses also has not been reported previously. The current results indicate that cell blocks prepared from residual ThinPrep material represent an additional reliable diagnostic tool in the evaluation of cervical samples. Furthermore, immunohistochemical studies may be helpful in differentiating significant preneoplastic changes from other cervical lesions, such as atrophy.     

Nasu-Hakola disease: a rare entity in Italy. Critical review of the literature

Nasu-Hakola disease (NHD, polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy, PLOSL) is a recessively inherited disorder characterized by systemic bone cysts and progressive presenile dementia associated with sclerosing encephalopathy. The disease has a worldwide distribution, but most patients have been reported in Finland and in Japan; in Italy there are anecdotal reports. The combination of neuropsychiatric symptoms and bone cysts is unique to this disease, which we believe to be underestimated in Italy. The molecular defect has been identified in loss-of-function mutations in the TYROBP gene in Finnish and in Japanese patients, and in the TREM2 gene in other families of different ethnic origins. We reviewed the international literature to define better the diagnostic steps and to draw the attention of neurologists and orthopaedic specialists to the disease. The identification of new cases followed by appropriate genetic counselling, genetic analysis, and study of the territorial distribution of affected patients could be a good strategy to follow in order to improve understanding of the disease.     

Relationship between maternal methadone dosage and neonatal withdrawal

OBJECTIVE: To determine whether maternal methadone dosage affects duration and degree of neonatal narcotic withdrawal. METHODS: This was a retrospective cohort study of pregnant women with opioid addiction who delivered live-born singletons between April 1990 and April 2001. Inpatient detoxification or outpatient methadone maintenance therapy was offered. Women who had a positive drug screen or whose neonate tested positive for opioids were considered to be supplementing. We evaluated indices of neonatal withdrawal according to the maximum daily methadone dosage in the last week of pregnancy. RESULTS: Seventy women with opioid addiction were followed. Median methadone dosage was 20 mg (range 0-150 mg), and 32 infants (46%) were treated for narcotic withdrawal. Among women who received less than 20 mg per day, 20-39 mg per day, and at least 40 mg per day of methadone, treatment for withdrawal occurred in 12%, 44%, and 90% of infants, respectively (P < 0.02). Methadone dosage was also correlated with both duration of neonatal hospitalization and neonatal abstinence score (r(s) =.70 and.73 respectively, both P <.001). Neonates were more likely to experience withdrawal if their mothers were supplementing with heroin, 68% versus 35% (P =.01). Regardless of supplementation, there was a significant relationship between methadone dosage and neonatal withdrawal (P <.05). CONCLUSION: Maternal methadone dosage was associated with duration of neonatal hospitalization, neonatal abstinence score, and treatment for withdrawal. Heroin supplementation did not alter this dose-response relationship. In selected pregnancies, lowering the maternal methadone dosage was associated with both decreased incidence and severity of neonatal withdrawal.     

A phased consent policy for cord blood donation

This article focuses on ethical and policy questions concerning when consent may be sought for the collection and donation of cord blood. It reviews the advantages and disadvantages of alternative times for securing consent, challenges common objections to seeking consent during labor or after collection, and describes a phased consent process--a process that permits consent during early labor to the ex utero collection of cord blood followed by after-consent collection to donation. The phased consent policy attends to the unique characteristics of cord blood collection and donation, respects donors and their families, maximizes the number and diversity of cord blood units collected, preserves the relationship between providers and patients, and preserves public trust in cord blood and other types of tissue banking.     

Common peroneal nerve injuries: results with one-stage nerve repair and tendon transfer

The authors report their experience in the treatment of common peroneal nerve (CPN) injuries using a one-stage procedure of nerve repair and tibialis posterior tendon transfer. A series of 45 patients with traumatic injury and graft repair of the CPN is presented. From 1988 to 1991, the six patients elected for surgery had only nerve repair: five ultimately did not recover, while muscle contraction in the remaining patient was graded M1-2. Since 1991, nerve surgery in our clinic was associated with tendon transfer procedures (39 cases) which were followed by a satisfactory reinnervation rate. Nerve transection and iatrogenic injuries, torsion/dislocation of the knee, complex biosseous fractures of the leg, and gunshot wounds showed excellent to fair results in decreasing order: in nerve sections, muscle recovery scored M3 or M4+ in all the patients, and in nerve ruptures due to severe dislocation of the knee, it was M3 or M4+ in 85% of cases. The association of microsurgical nerve repair and tendon transfer has changed the course of CPN injuries.     

Effects of a saccharin and cyclamate mixture on rat embryos

Sodium saccharin (NaS) and calcium cyclamate (CaC) are artificial sweeteners widely used in food and drink. To evaluate their toxicological effects on preimplantation mammalian embryos, pregnant rats were gavaged with 1.65 mg NaS/kg bw + 3.85 mg CaC/kg bw (DI) or 6.6 mg NaS/kg bw + 15.4 mg CaC/kg bw (D2) on days 1, 2, 3 and 4 of pregnancy (positive vaginal smear = day 1). The female rats were killed on day 5 of the pregnancy (GD 5), maternal organs weighed, and the blastocysts collected, counted and evaluated for gross morphology, cell number and mitotic index. There was no alteration in maternal organ weights, but there was an increase of the cell number/embryo in the dams treated with that NaS + CaC mixtures (D1 = 37.20 +/- 7.96; D2 = 37.26 +/- 10.90) compared to control group (32.24 +/- 6.73). Embryos whose dams were exposed to NaS + CaC may have adapted for implantation into the uterus but more studies are needed to demonstrate this mechanism of action.     

Quality assurance in diagnostic radiology: practical outcomes

Over the last four years, our Health Physics Department has implemented a quality control programme focusing on the performance of the diagnostic X-ray machines in use at our hospital. The results of the tests performed (X-ray and light field alignment, tube voltage reproducibility and accuracy, ) were used to compare the 1999 and 2002 findings by means of the chi squared and Fischer statistical tests. The comparison has demonstrated that the decrease in the number of non-conformities, also emerging from a simple comparative analysis on the experimental data, was statistically significant with a p<0.05 for all of the X-ray machines examined. This finding confirms that our quality control programme had positive effects on the overall performance of the hospital diagnostic X-ray equipment, and appears to justify the resources employed for its implementation.     

Loss of inhibitor of apoptosis proteins as a determinant of polyamine analog-induced apoptosis in human melanoma cells

We have previously shown that the clinically relevant polyamine analog N1,N11-diethylnorspermine (DENSPM) causes rapid apoptosis in human melanoma SK-MEL-28 cells via a series of events that include mitochondrial release of cytochrome c and activation of the caspase cascade. Upstream to these events, DENSPM downregulates polyamine biosynthesis and potently upregulates polyamine catabolism at the level of spermidine/spermine N1-acetyltransferase (SSAT). In searching for downstream effectors that either contribute to or abrogate the apoptotic response, we observed that DENSPM treatment of SK-MEL-28 cells for 30 h led to cytosolic release of Smac/Diablo, a mitochondrial protein known to bind and inhibit the function of inhibitor of apoptosis proteins (IAPs). Subsequently, we found that DENSPM markedly lowered survivin and ML-IAP protein (but not XIAP) levels by 18 h via an apparently Smac/Diablo-independent pathway. Proteasome inhibitors fully prevented survivin and ML-IAP protein loss as well as apoptosis, suggesting that the proteasome-mediated degradation of survivin and ML-IAP is causally linked to the cellular outcome. We also observed that structural analogs of DENSPM which differentially induced SSAT and apoptosis lowered survivin and ML-IAP levels in a manner that correlated with enzyme activity. The linkage between IAPs and SSAT was more directly established by the finding that selective prevention of SSAT induction by small interfering RNA prevented survivin and ML-IAP loss as well as apoptosis during DENSPM treatment. Among the melanoma cell lines (SK-MEL-28, MALME-3M, A375 and LOX), survivin degradation correlated temporally with the onset of DENSPM induced apoptosis or growth inhibition. By contrast, ML-IAP degradation occurred only during rapid apoptosis seen in SK-MEL-28 cells. These data suggest a sequence of events whereby DENSPM induction of SSAT leads to loss of IAP proteins and a more fulminate apoptotic response. The findings implicate survivin and ML-IAP as important determinants of polyamine analog drug action in melanoma cells.     

Vesicle-bound EBV-BART13-3p miRNA in circulation distinguishes nasopharyngeal from other head and neck cancer and asymptomatic EBV-infections

Cell-free microRNA (miRNA) in biofluids released by tumors in either protein or vesicle-bound form, represent promising minimally-invasive cancer biomarkers. However, a highly abundant non-tumor background in human plasma and serum complicates the discovery and detection of tumor-selective circulating miRNAs. We performed small RNA sequencing on serum and plasma RNA from Nasopharyngeal Carcinoma (NPC) patients. Collectively, Epstein Barr virus-encoded miRNAs, more so than endogenous miRNAs, signify presence of NPC. However, RNAseq-based EBV miRNA profiles differ between NPC patients, suggesting inter-tumor heterogeneity or divergent secretory characteristics. We determined with sensitive qRT-PCR assays that EBV miRNAs BART7-3p, BART9-3p and BART13-3p are actively secreted by C666.1 NPC cells bound to extracellular vesicles (EVs) and soluble ribonucleoprotein complexes. Importantly, these miRNAs are expressed in all primary NPC tumor biopsies and readily detected in nasopharyngeal brushings from both early and late-stage NPC patients. Increased levels of BART7-3p, BART9-3p and particularly BART13-3p, distinguish NPC patient sera from healthy controls. Receiver operating characteristic curve analysis using sera from endemic NPC patients, other head and neck cancers and individuals with asymptomatic EBV-infections reveals a superior diagnostic performance of EBV miRNAs over anti-EBNA1 IgA serology and EBV-DNA load (AUC 0.87–0.96 vs 0.86 and 0.66 respectively). The high specificity of circulating EBV-BART13-3p (97%) for NPC detection is in agreement with active secretion from NPC tumor cells. We conclude EV-bound BART13-3p in circulation is a promising, NPC-selective, biomarker that should be considered as part of a screening strategy to identify NPC in endemic regions.