Characterization and prediction of IVF cycles generating “slow-cleaving” embryos

Purpose To characterize and predict cycles generating slowcleaving embryos in in vitro fertilization, 86 cycles were retrospectively divided into two groups (slow, n=41, and fast, n=45 according to whether the number of blastomeres per embryo on day 3 was or > than the mean of the distribution, respectively.Results Cycles generating slowcleaving embryos were treated with luteinizing hormonereleasing hormone agonist before ovarian stimulation for a shorter period (12.1±0.5 versus 15.6±1.1 days; P0.01) and had higher immaturity grade of oocyte-corona-cumulus complexes which resulted in embryos (1.6±0.1 vs 1.3±0.1; P0.05) when compared to cycles producing fastcleaving embryos. Both variables entered in a logistic regression model applied in order to predict the probability of a cycle generating slowcleaving embryos (goodness-of-fit chisquare=180.0, degrees of freedom (df)=80, P=0.4786. This model predicted correctly 86.7% (13 of 15) of cycles generating slowcleaving embryos and 83.3% (10 of 12) of cycles producing fastcleaving embryos when the estimated probability of a cycle producing slowcleaving embryos was 0.7 or 0.3, respectively.Conclusion Shorter treatment with hormone-releasing hormone agonist before ovarian stimulation and higher immaturity grade of oocyte-corona-cumulus complexes which result in embryos are predictive characteristics of in vitro fertilization cycles generating slow-cleaving embryos.     

Dental caries and periodontal disease (prevention and control methods)

There is a compelling need to apply preventive programs in both private and community practice of dentistry. This is to maintain improvements in oral health in developed and industrialized countries, and to stem increases in oral diseases in underserved and developing ones. At the outset, the terms prevention and control must be understood. The former is considered to mean a procedure or course of action that prevents the onset of disease, whereas the latter, implies reversing or stabilizing disease conditions. To be more precise, prevention will refer to the pre-pathologic or pre-clinical stage encompassing the promotive and specific protection levels--primary prevention stage. On the other hand, control will encompass early diagnosis and prompt treatment, disability limitation and rehabilitation levels-termed also collectively, as pathologic, clinical and final stages, or secondary and tertiary prevention. Community-based programs are usually structured to compliment therapeutic interventions of oral diseases, as well as prevention. In this era, and towards the next millennium, preventive and control programs are given high priorities in order to minimize the need for curative, restorative and therapeutic management of oral diseases. This review of the literature will give emphasis on established methods and programs for the prevention and control of the two most common oral diseases, dental caries and periodontal disease. The problems, background, and oral health objectives for the year 2000 as proposed by the World Health Organization (WHO) and the Federation Dentaire Internationale (FDI), as well as the recent advances in oral health relative to these diseases will be discussed. Finally, to better improve the efficacy of existing prevention and control methods, research needs and areas of concern relative to these diseases will be given consideration.     

Breast Carcinoma in Childhood and Adolescence: Case Report and Review of the Literature

Secretory breast carcinoma is a rare tumor originally described in children and adolescent women with a characteristic morphology and a controversial choice of treatment. We report an additional case of a 4-year-old girl with a breast tumor diagnosed as a secretory carcinoma without involvement of the axillary lymph nodes. The therapy consisted of simple mastectomy and low axillary dissection. She presented with a local recurrence near the surgical scar 8 months later, and a wide elliptical excision of the scar and underlying tissue was performed with subsequent radiotherapy of the surgical bed. This tumor has a relatively benign behavior and rarely metastasizes. A literature review revealed only 22 cases of breast carcinoma in childhood and adolescence. ▪     

Blood-retinal barrier breakdown investigated by real-time magnetic resonance imaging after gadolinium-diethylenetriaminepentaacetic acid injection

Recent magnetic resonance imaging (MRI) studies show that gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) entry into the vitreous space can be used as a qualitative marker of blood-retinal barrier (BRB) disruption. To determine if a more quantitative measurement of BRB breakdown could be obtained, the utility of acquiring real-time, T1-weighted proton images was studied after Gd-DTPA injection. Two days before the MRI experiment, panretinal photocoagulation was done. The mean signal intensity over selected regions-of-interest (ROI) in the vitreous and anterior chamber was followed before and after (0, 10, 20, 30, 45, and 60 min) Gd-DTPA injection (1.0 mmol/kg, intravenously). At every laser power setting used in this study (0, 200, 400, 600, and 800 mW), the change in the mean signal intensity could be approximated by a simple exponential equation. However, the time constants determined for these curves were too imprecise to be useful as correlates between laser power and BRB breakdown. The slope of the line fit to the data in the first 20 min postinjection (ie, an initial-rate analysis) was a more precise correlate between BRB breakdown and laser power. This slope represented the rate of change in mean signal intensity in the ROI as a result of the entry of Gd-DTPA, and it was called the "leakiness" parameter. The leakiness parameter reflected changes in the permeability surface area product of the BRB if the blood flow and the Gd-DTPA arterial concentration immediately after injection were approximately the same between animals.     

Morphological changes in ocular surface in dry eyes and other disorders by impression cytology

A study was conducted on 107 eyes of 70 patients with dry eye disorders and mechanical and chemical extrinsic alterations and 64 eyes of 32 control subjects in order to describe a possible specific response of the conjunctival and corneal surface. We found the presence of snakelike chromatin cells and other nuclear changes, squamous metaplasia, and inflammatory cells in the conjunctiva in all groups. A decrease in goblet cell densities was also found in all groups, except for patients with blepharoconjunctivitis. The corneal cells were slightly larger in patients with keratoconjunctivitis sicca.Correspondence to: L. Rivas     

Zum Beweiswert von Diatomeen im Knochenmark beim Ertrinkungstod

Zusammenfassung Anhand tierexperimenteller Untersuchungen wurde neuerlich der Frage nach dem qualitativen und quantitativen Übertritt von Diatomeen beim Ertrinken in den großen Kreislauf und somit auch ins Knochenmark nachgegangen. Es kam eine Versuchsanordnung zur Anwendung, die dieser komplexen Fragestellung gerecht wird. So wurden den Tieren (Kaninchen) knapp vor dem Ertränken ein Hinterlauf amputiert und die Gefäße einer Niere abgeklemmt, um auch Diatomeenwerte vor dem Ertrinken zu erhalten. Sodann erfolgte die qualitative und quantitative Untersuchung des Knochenmarks beider Hinterläufe und beider Nieren auf Diatomeen. Dabei zeigte sich in allen Fällen ein Anstieg der Diatomeenzahl in den zuvor nicht amputierten Hinterläufen. Aufgrund der Versuchsergebnisse und den bei der Untersuchung gewonnenen Erkenntnissen wird auf jene Kriterien eingegangen, deren Beachtung vorausgesetzt, der Diatomeenbefund einen wertvollen diagnostischen Hinweis für einen Ertrinkungstod liefern kann. Auf eine mögliche Asservierung der Ertrinkungsflüssigkeit im Magen wird hingewiesen.Auszugsweise vorgetragen anläßlich des Treffens der Süddeutschen Rechtsmediziner in München, Mai 1981     

Identification and characterization of a T-helper peptide from carcinoembryonic antigen.

PURPOSE: The purpose of this research was to identify promiscuous T-helper cell determinants (THd) from carcinoembryonic antigen (CEA) to be used to prime T-cell help for cancer therapy. CEA was selected because this antigen is expressed in an important variety of carcinomas. EXPERIMENTAL DESIGN: Potential promiscuous THd from CEA were predicted using available computer algorithms. Predicted peptides were synthesized and tested in binding experiments to different HLA-DR molecules. Binder peptides were then used to prime T-cell responses both in vitro and in vivo. RESULTS: Twenty 15-mer peptides from CEA were predicted to bind to different HLA-DR molecules. The promiscuous character of these peptides was demonstrated in binding experiments. Fifteen of 20 peptides tested were able to bind to HLA-DR4, but only CEA (625-639) was shown to be presented after processing of recombinant CEA. CEA (625-639) was also found to be presented by HLA-DR53. Moreover, immunization of HLA-DR4 transgenic mice with CEA (625-639) in conjunction with class I epitope OVA (257-264), induced a CTL response specific of OVA (257-264). CONCLUSIONS: CEA (625-639) might be a relevant promiscuous THd peptide for cancer therapy.     

Experimental validation tests of fast Fourier transform convolution and multigrid superposition algorithms for dose calculation in low-density media.

BACKGROUND AND PURPOSE: Modern conformal radiotherapy treatments require accurate dose calculation in any relevant clinical situation. One of these situations is the treatment of lung tumors, where irradiation has to be planned under challenging conditions for dose calculation. In this study we assess the errors in dose values predicted by fast Fourier transform convolution (FFTC) and multigrid superposition (MGS) algorithms implemented in a commercial treatment planning system (TPS). MATERIALS AND METHODS: FFTC and MGS algorithms were used in a FOCUS 3.0.0 (Computerized Medical Systems, USA) to calculate doses in treatment plans using photon beams of 6 and 25 MV nominal energy from a Saturne 43 linac (GE Medical Systems, USA). A 10x10-cm beam irradiating a mediastinum-lung and a thoracic wall-lung-thoracic wall modeled geometry was assessed. The calculated data were compared with measurements performed with radiographic films and ionization chamber. RESULTS: FFTC algorithm leads to an average deviation from ionometric dose measurements of over 10%. Discrepancies between measured and calculated beam fringe values (distance between 50 and 90% isodose lines) of up to 8 mm were observed. For MGS algorithm, all the points assessed in both geometries fulfilled the 3%-3 mm accuracy criteria and the average deviation of absolute dose was about 1%. A maximum of 3 mm deviation in the beam fringe for any depth was found and was within 2 mm beyond the buildup region. Deviations between ionometric and film measurements were within 3%. CONCLUSIONS: MGS algorithm assesses with reasonable accuracy dose distributions and absolute dose in inhomogeneous regions like the lung region. Therefore, and respecting the inhomogeneity dose calculation, the system could be used in routine clinical practice and in dose-escalation programs. This is not true in the case of FFTC algorithm which leads to errors greater than 10% in the absolute dose calculation and underestimates the beam fringe by up to 8 mm.