Precision Medicine in Castration-Resistant Prostate Cancer: Advances, Challenges, and the Landscape of PARPi Therapy-A Narrative Review

After recent approvals, poly-adenosine diphosphate [ADP]-ribose polymerase inhibitors (PARPis) have emerged as a frontline treatment for metastatic castration-resistant prostate cancer (mCRPC). Unlike their restricted use in breast or ovarian cancers, where approval is limited to those with BRCA1/2 alterations, PARPis in mCRPC are applied across a broader spectrum of genetic aberrations. Key findings from the phase III PROPEL trial suggest that PARPis' accessibility may broaden, even without mandatory testing. An increasing body of evidence underscores the importance of distinct alterations in homologous recombination repair (HRR) genes, revealing unique sensitivities to PARPis. Nonetheless, despite the initial effectiveness of PARPis in treating BRCA-mutated tumors, resistance to therapy is frequently encountered. This review aims to discuss patient stratification based on biomarkers and genetic signatures, offering insights into the nuances of first-line PARPis' efficacy in the intricate landscape of mCRPC.

Two New Modifications of the InterCriteria Analysis

In the present work two modifications of the InterCriteria Analysis are proposed in order to extend its theoretical foundation. The results obtained from the application of these methods over real data (from patients with prostate carcinoma) have been analyzed to determine the reliability of the calculated consonance and dissonance. The similarity scores obtained by the modified versions of the InterCriteria Analysis are close to those given by the classical InterCriteria Analysis, as well as to the values of the correlation coefficients between the considered criteria. This shows the reliability of the proposed modification with respect to determining the consonance and dissonance between criteria in different problems.

Depressive disorders and quality of life in patients with acute coronary syndrome in real clinical practice

Background

The prevalence of depressive disorders has become more significant in recent years.

Objective

To study the prevalence of depressive disorders using Zung Anxiety Rating Scale (ZARS) in patients with acute coronary syndrome (ACS) in the daily work of the Regional Vascular Center (RVC) in various gender and social subgroups and to compare their severity with the life quality level.

Materials and methods

The survey included 116 (57 female and 59 male) patients, admitted to RVC with ACS from March to November 2020 (Group I), and 49 patients without ACS, comparable with demographic parameters (Group II). Patients were interviewed with the use of ZARS and the life quality assessment questionnaire (SF-36). Statistical data processing was carried out using Statistica v.13.3, Mann–Whitney U-test, Pearson's chi-squared test, Spearman's rank correlation coefficient. P values <0.05 were considered statistically significant.

Results

In Group I the score on ZARS was higher or equal to 50 (depression) in 18% of cases: 15% female and 3% male patients (p<0.05). The average score on ZARS was notably higher in women than in men (p<0.05). In Group II depression was detected in 27% of cases, without gender differences. A negative correlation was established for the indicators of ZARS and SF-36: in Group I r=−0.62, p<0.05, in Group II r=−0.76, p<0.05. In Group I indicators of health physical component (SF-36) among women were: physical functioning 50, role functioning 34, general health 51, in men: 80, 58 and 63 respectively (p<0.05). In Group II these indicators significantly differed only in physical functioning: 60 female and 72 male. In Group I depression was observed in 2% of working and in 30% of non-working patients (p<0.05); in Group II: 0% and 34% respectively. In Groups I and II depression was found in 10% and 5% among married, in 31% and 43% among unmarried patients (p<0.05). In Group I depression was detected in 31% among patients with diabetes, in 12% - without diabetes (p<0.05). The other analyzed diseases did not have a significant effect on the depression score.

Conclusions

The presence of ACS did not effect on the severity of depressive disorders in comparison with patients with other cardiac pathology, but among women with ACS their severity and prevalence was significantly higher. The severity of depressive disorders was inversely associated with life quality. Among patients with ACS, the health physical component according to SF-36 was significantly lower in women than in men; without ACS - no gender differences. Lack of work and marriage negatively affected on the prevalence of depression among all examined patients. Patients with ACS and diabetes had more elevated level of depression; the presence of depressive disorders was in close relationship with the health physical component among women (according to SF-36). It is necessary to develop and implement specialized rehabilitation programs for this subgroup of patients.

Funding Acknowledgement

Type of funding sources: None.

Stone composition of renal stone formers from different global regions

OBJECTIVE

To study urinary stone composition patterns in different populations around the world.

MATERIALS AND METHODS

Data were collected by reviewing charts of 1204 adult patients of 10 countries with renal or ureteral stones (> 18 years) in whom a stone analysis was done and available. Any method of stone analysis was accepted, but the methodology had to be registered.

RESULTS

In total, we observed 710 (59%) patients with calcium oxalate, 31 (1%) with calcium phosphate, 161 (13%) with mixed calcium oxalate/calcium phosphate, 15 (1%) with carbapatite, 110 (9%) with uric acid, 7 (< 1%) with urate (ammonium or sodium), 100 (9%) with mixed with uric acid/ calcium oxalate, 56 (5%) with struvite and 14 (1%) with cystine stones. Calciumcontaining stones were the most common in all countries ranging from 43 to 91%. Oxalate stones were more common than phosphate or mixed phosphate/oxalate stones in most countries except Egypt and India. The rate of uric acid containing stones ranged from 4 to 34%, being higher in Egypt, India, Pakistan, Iraq, Poland and Bulgaria. Struvite stones occurred in less than 5% in all countries except India (23%) and Pakistan (16%). Cystine stones occurred in 1% of cases.

CONCLUSIONS

The frequency of different types of urinary stones varies from country to country. Calcium-containing stones are prevalent in all countries. The frequency of uric acid containing stones seems to depend mainly on climatic factors, being higher in countries with desert or tropical climates. Dietary patterns can also lead to an increase in the frequency of uric acid containing stones in association with high obesity rates. Struvite stones are decreasing in most countries due to improved health conditions.

Obesity rates in renal stone formers from various countries

OBJECTIVE

To collect evidence on the rate of obesity in renal stone formers (RSFs) living in different climatic areas and consuming different diets.

MATERIALS AND METHODS

Data of adult renal stone formers were retrospectively collected by members of U-merge from 13 participant centers in Argentina, Brazil, Bulgaria (2), China, India, Iraq (2), Italy (2), Nigeria, Pakistan and Poland. The following data were collected: age, gender, weight, height, stone analysis and procedure of stone removal.

RESULTS

In total, 1689 renal stone formers (1032 males, 657 females) from 10 countries were considered. Average age was 48 (±14) years, male to female ratio was 1.57 (M/F 1032/657), the average body mass index (BMI) was 26.5 (±4.8) kg/m2. The obesity rates of RSFs in different countries were significantly different from each other. The highest rates were observed in Pakistan (50%), Iraq (32%), and Brazil (32%), while the lowest rates were observed in China (2%), Nigeria (3%) and Italy (10%). Intermediate rates were observed in Argentina (17%), Bulgaria (17%), India (15%) and Poland (22%). The age-adjusted obesity rate of RSFs was higher than the age-adjusted obesity rate in the general population in Brazil, India, and Pakistan, whereas it was lower in Argentina, Bulgaria, China, Italy, and Nigeria, and similar in Iraq and Poland.

CONCLUSIONS

The age-adjusted obesity rate of RSFs was not higher than the age-adjusted obesity rate of the general population in most countries. The relationship between obesity and the risk of kidney stone formation should be reconsidered by further studies carried out in different populations.

Cones, needles and wood: Micraspis (Micraspidaceae, Micraspidales fam. et ord. nov.) speciation segregates by host plant tissues

Micraspis acicola was described more than 50 years ago to accommodate a phacidium-like fungus that caused a foliar disease of Picea mariana. After its publication, two more species were added, M. strobilina and M. tetraspora, all of them growing on Pinaceae in the Northern Hemisphere, but each species occupying a unique type of host tissue (needles, cones or wood). Micraspis is considered to be a member of class Leotiomycetes, but was originally placed in Phacidiaceae (Phacidiales), later transferred to Helotiaceae (Helotiales) and recently returned to Phacidiales but in a different family (Tympanidaceae). The genus remains poorly sampled, and hence poorly understood both taxonomically and ecologically. Here, we use morphology, cultures and sequences to provide insights into its systematic position in Leotiomycetes and its ecology. Our results show that the genus should not be included in Tympanidaceae or Phacidiaceae, and support the erection of a new family and order with a unique combination of morphological features supported by molecular data.

Extended cavity quantum cascade laser with cavity resonator integrated grating filter

We report on an extended cavity quantum cascade laser based on a cavity resonator integrated grating filter (CRIGF) that acts as both cavity end-reflector and spectral selector. Stable, mode-hop free, single-mode emission around 2150 cm^-1 is obtained over large injection current ranges (more than 50 mA) with a typical threshold around 290 mA. A digital frequency tuning over more than 65 cm^-1 is obtained by changing the periodicity of the CRIGF ending the extended cavity.

[THE LEVEL OF PROTECTION FROM OXIDATIVE STRESS AND THREE-YEAR DYNAMICS OF STRUCTURAL AND FUNCTIONAL CHANGES OF THE MYOCARDIUM IN CHRONIC ISCHEMIC HEART DISEASE IN MEN]

Aim - to assess the nature and three-year dynamics of structural and functional changes in the cardiovascular system in relation to the levels of enzymatic and non-enzymatic antioxidants in chronic coronary heart disease in men. The study included 246 men aged 48 to 65 years (mean age 58 years (53,0; 63,0)) with stable form of ischemic heart disease - angina FC II-III CHF I-III FC (NYHA), observed during 2012-2015. To assess the level of oxidative stress in all patients by ELISA was determined by lipid peroxide, total antioxidant status (CCA) and levels of non-enzymatic antioxidant bilirubin (BR). Patients were divided into 2 groups according to the level of serum BR: the main group - 146 patients with the level of BR< 8.0 µmol/l; the control group-100 patients with the level of BR ≥8.0 µmol/l. Assessment of the structural and functional state of the myocardium included ECG, XM ECG, EchoCG, VEM test. A decrease in the level of protection against oxidative stress (OS) in men with stable CHD in the form of a significant increase in the level of lipid peroxides and a decrease in the OAS index was found. In the study group OxyStat, total cholesterol and LDL cholesterol were significantly higher (p<0.01)., and ImAnOx - significantly lower than in the control group (p<0.01). A high degree of direct relationship between the level of blood BR and the indicator of AOC is established. Three-year dynamic observation showed a close relationship between the processes of cardiovascular system remodeling and OS components. The high level of OS in men with stable ischemic heart disease is accompanied by adverse changes in the geometry of the left ventricle (eccentric non-dilatated hypertrophy, an increase in the number of segments with hypokinesis), which leads to the progression of chronic heart failure with the risk of ischemic and arrhythmic reactions to physical activity.

Mid-infrared cavity resonator integrated grating filters

Cavity Resonator Grating Filters (CRIGFs) working in the Mid-Infrared are reported, with narrow-band resonant reflectivity peaks around 2200 cm^-1 (4.6 µm). They are fabricated in the GaAs/AlGaAs material system that can potentially cover the whole [1-12] µm spectral range. TE-polarized peak reflectivity is 30% with a 4 cm^-1 full width at half maximum.

2 × 1D crossed strongly modulated gratings for polarization independent tunable narrowband transmission filters

We design a narrowband polarization independent transmission guided mode resonance filter whose center wavelength is tunable with respect to the angle of incidence. The device is composed of two identical structures assembled back to back. Each half structure is a dielectric multilayer stack in which a grating is engraved. This so-called 2×1D crossed gratings component has already been demonstrated for reflection filtering [Opt. Lett.36, 1662 (2011)OPLEDP0146-959210.1364/OL.36.001662; Opt. Lett.39, 6038 (2014)OPLEDP0146-959210.1364/OL.39.006038]. The functioning in transmission requires the use of a high index material for the grating bumps. For the design, we resort to a clustering global optimization algorithm, used for the first time to our knowledge for grating structures. We demonstrated two filters with a quality factor of about 4000, tunable over more than 15 nm when the angle of incidence varies over a range of 4°, and with a transmittivity at resonance greater than 95% whatever the incident polarization.

Electromagnetic modeling of large subwavelength-patterned highly resonant structures

The rigorous modeling of large (hundreds of wavelengths) optical resonant components patterned at a subwavelength scale remains a major issue, especially when long range interactions cannot be neglected. In this Letter, we compare the performances of the discrete dipole approximation approach to that of the Fourier modal, the finite element and the finite difference time domain methods, for simulating the spectral behavior of a cavity resonator integrated grating filter (CRIGF). When the component is invariant along one axis (two-dimensional configuration), the four techniques yield similar results, despite the modeling difficulty of such a structure. We also demonstrate, for the first time to the best of our knowledge, the rigorous modeling of a three-dimensional CRIGF.

Polymorphisms in androgen metabolism genes AR, CYP1B1, CYP19, and SRD5A2and prostate cancer risk and aggressiveness in Bulgarian patients

BACKGROUND/AIM

The aim of our study was to elucidate the role of polymorphisms in AR, CYP1B1, CYP19, and SRD5A2 genes for prostate cancer (PC) development in Bulgarian patients.

MATERIALS AND METHODS

We genotyped 246 PC patients and 261 controls (155 with benign prostate hyperplasia and 107 healthy population controls) using direct sequencing, PCR-RFLP, SSCP, and fragment analysis.

RESULTS

The allele and genotype frequencies of most of the studied variants did not differ significantly between cases and controls. Increased frequencies of the C/C genotype and C allele of rs1056837 in CYP1B1, and genotype 7/8 of the (TTTA)n repeat polymorphism in CYP19, were observed in patients in comparison with controls.The 8/9 and the 7/12 genotypes of (TTTA)n in CYP19 showed suggestive evidence for association with decreased prostate cancer risk and the risk for aggressive disease, respectively. The haplotype analysis revealed 2 CYP1B1 haplotypes associated with PC risk reduction.

CONCLUSION

Some CYP1B1 haplotypes and genotypes of the CYP19 (TTTA)n repeat appeared to be associated with disease risk or aggressiveness in Bulgarian PC patients. In contrast, the SRD5A2 polymorphisms (V89L and (TA)n repeat), the CAG repeat in AR, and the Arg264Cys variant in CYP19A1 are most likely not implicated in prostate carcinogenesis.

Laparoscopic varicocelectomy in the management of chronic scrotal pain

Background and Objectives:

To evaluate the usefulness of laparoscopic varicocelectomy in the management of chronic scrotal pain.

Methods:

Between 2009 and 2011, 48 patients in total were treated with laparoscopic varicocelectomy for dull scrotal pain that worsened with physical activity and was attributed to varicoceles. All patients were followed up at 3 and 6 months and biannually thereafter with a physical examination, visual analog scale score, and ultrasonographic scan in selected cases.

Results:

The mean age was 38.2 years (range, 23–54 years). The mean follow-up period was 19.6 months (range, 6–26 months). Bilateral varicoceles were present in 7 patients (14.6%), and a unilateral varicocele was present in 41 (85.4%). The varicocele was grade 3 in 27 patients (56.3%), grade 2 in 20 (41.6%), and grade 1 in 1 (2.1%). The mean preoperative visual analog scale score was 4.8 on a scale from 0 to 10. The mean postoperative visual analog scale score at 3 months was 0.8. After the procedure, 42 patients (87.5%) had a significant improvement in the visual analog scale score (P < .001); 5 (10.4%) had symptom improvement, although it was not statistically significant; and 1 (2.1%) remained unchanged. During follow-up, we observed 5 recurrences (10.4%) whereas de novo hydrocele formation was identified in 4 individuals (8.3%).

Conclusion:

Laparoscopic varicocelectomy is efficient in the treatment of symptomatic varicoceles with a low complication rate. However, careful patient selection is necessary because it appears that individuals presenting with sharp, radiating testicular pain and/or a low-grade varicocele are less likely to benefit from this procedure.

Design of metallic nanoparticle gratings for filtering properties in the visible spectrum

Plasmonic resonances in metallic nanoparticles are exploited to create efficient optical filtering functions. A finite element method is used to model metallic nanoparticle gratings. The accuracy of this method is shown by comparing numerical results with measurements on a two-dimensional grating of gold nanocylinders with an elliptic cross section. A parametric analysis is then performed in order to design efficient filters with polarization dependent properties together with high transparency over the visible range. The behavior of nanoparticle gratings is also modeled using the Maxwell-Garnett homogenization theory and analyzed by comparison with the diffraction of a single nanoparticle. The proposed structures are intended to be included in optical systems that could find innovative applications.

Transmission properties of slanted annular aperture arrays. Giant energy deviation over sub-wavelength distance

This paper is devoted to the study of the transmission properties of Slanted Annular Aperture Arrays made in perfectly conducting metal. More precisely, we consider the transmission based on the excitation of the cutoff-less guided mode, namely the TEM mode. We numerically and analytically demonstrate some intrinsic properties of the structure showing a transmission coefficient of at least 50% of an unpolarized incident beam independently of the illumination configuration (angle and plane of incidence). The central symmetry exhibited by the structure is analytically exploited to demonstrate the existence of a polarization state for which all the incident energy is transmitted through the sub-wavelength apertures when the eigenmode is excited, whatever are the illumination and the geometrical parameters. For this state of polarization, the laminar flow of the energy through the structure can exhibit giant deviation over very small distances. An example of energy flow deviation of 220° per wavelength is presented for illustration. The results presented in this paper could be considered as an important contribution to the understanding of the enhanced transmission phenomenon based on the excitation of guided modes.

Waveguide mode in the box with an extraordinary flat dispersion curve

The extraordinary flattening of the dispersion curve of the so-called cavity resonator integrated guided-mode resonance filters (CRIGFs) is analyzed and explained as due to the intramode coupling imposed by the external Bragg resonators. CRIGFs are composed of a grating coupler (guided-mode resonance filter, GMRF) put between two distributed Bragg reflectors (DBRs). They form a cavity box in which the excited guided mode is confined. This confinement provides resonances with small spectral width (smaller than 1 nm for optical wavelengths) and extraordinary wide angular acceptance (several degrees). At a first glance, one may think that similar performances could be obtained while putting the GMRF and the DBR one above the other, forming a so-called "doubly periodic" grating, as in this configuration also the DBR confines the mode. Yet, the angular acceptance of CRIGFs is an order of magnitude greater than in classical gratings, even with complex pattern. The aim of the present paper is to identify the phenomenon responsible for the extraordinary large angular acceptance of CRIGFs. We numerically calculate, for the first time to the best of our knowledge, the dispersion curve of the mode excited in the CRIGF. The dispersion curve shows a flat part, where the resonance wavelength is quasi-independent of the angle of incidence, and the flattening grows with the width of the Bragg reflector. We develop an approximate coupled four-wave model, which predicts the extraordinary flattening as a consequence of an additional coupling of the waveguide modes of the GMRF provided by the Bragg grating, that does not exist in the "doubly periodic" gratings.

Combinations of serum prostate-specific antigen and plasma expression levels of let-7c, miR-30c, miR-141, and miR-375 as potential better diagnostic biomarkers for prostate cancer

In the current study, expression levels of let-7c, miR-30c, miR-141, and miR-375 in plasma from 59 prostate cancer (PC) patients with different clinicopathological characteristics and two groups of controls: 16 benign prostatic hyperplasia (BPH) samples and 11 young asymptomatic men (YAM) were analyzed to evaluate their diagnostic and prognostic value in comparison to prostate-specific antigen (PSA). miR-375 was significantly downregulated in 83.5% of patients compared to BPH controls and showed stronger diagnostic accuracy (area under the curve [AUC]=0.809, 95% CI: 0.697-0.922, p=0.00016) compared with PSA (AUC=0.710, 95% CI: 0.559-0.861, p=0.013). Expression levels of let-7c showed potential to distinguish PC patients from BPH controls with AUC=0.757, but the result did not reach significance. Better discriminating performance was observed when combinations of studied biomarkers were used. Sensitivity of 86.8% and specificity of 81.8% were reached when all biomarkers were combined (AUC=0.877) and YAM were used as calibrators. None of the studied microRNAs (miRNAs) showed correlation with clinicopathological characteristics. PSA levels were significantly correlated with the Gleason score, tumor stage, and lymph node metastasis with Spearman correlation coefficients: 0.612, 0.576, and 0.458. In conclusion, the combination of the studied circulating plasma miRNAs and serum PSA has the potential to be used as a noninvasive diagnostic biomarker for PC screening outperforming the PSA testing alone.

Cavitation on deterministically nanostructured surfaces in contact with an aqueous phase: a small-angle neutron scattering study

The structure of deterministically nanopatterned surfaces created using a combination of electron beam lithography and reactive ion etching was evaluated using small-angle neutron scattering (SANS). Samples exhibit 2D neutron scattering patterns that confirm the presence of ordered nanoscale cavities consistent with the targeted morphologies as well as with SEM data analysis. Comparison of SANS intensities obtained from samples in air and in contact with an aqueous phase (pure deuterium oxide, D2O, or a contrast matched mixture of D2O + H2O) reveals formation of stable gaseous nanobubbles trapped inside the cavities. The relative volume of nanobubbles depends strongly on the hydrophobicity of the cavity walls. In the case of hydrophobic surfaces, nanobubbles occupy up to 87% of the total cavity volume. The results demonstrate the high degree of sensitivity of SANS measurements for detecting and characterizing nano- and mesoscale bubbles with the volume fraction as low as ∼10(-6).

Evaluation of the clinical value of the newly identified urine biomarker HIST1H4K for diagnosis and prognosis of prostate cancer in Bulgarian patients

PURPOSE

Searching for diagnostic and prognostic biomarkers for prostate cancer (PC) is main public health priority. DNA methylation in body fluids is a stable, easily detectable and promising PC biomarker. The major advantages of urine-based assays are their noninvasive nature and the ability to monitor PC with heterogeneous foci. The aim of this study was to determine the diagnostic value of the recently identified candidate PC biomarker HIST1H4K.

METHODS

We investigated DNA methylation of HIST1H4K in urine samples from 57 PC patients, 29 controls with benign prostatic hyperplasia (BPH) and 50 young asymptomatic men (YAM) by MethyLight real-time PCR.

RESULTS

The frequency of HIST1H4K promoter hypermethylation significantly discriminated PC patients from YAM (AUC =0.763; 95% CI 0.672-0.839; p<0.0001), but did not show any statistical difference between PC patients and BPH controls (AUC=0.513, 95% CI 0.402-0.622; p=0.8255). HIST1H4K could not outperform the prostatic specific antigen (PSA) in our sample (AUC=0.785; 95% CI 0.679-0.870; p<0.0001). Methylation of HIST1H4K showed significant correlation with aging (r=0.5418; p<0.0001), but with no other clinicopathological characteristics.

CONCLUSION

The results suggest that the promoter hypermethylation of HIST1H4K is rather due to aging than related to prostate carcinogenesis. To elucidate this observation analysis of larger samples is needed.

Whispering gallery modes and other cavity modes for perfect backscattering and blazing

We demonstrate the possibility to obtain perfect blazing both in Littrow and off-Littrow mountings using diffractive systems consisting of a plane metallic substrate and dielectric structures that can support cavity modes. The resonances are located at a relatively large distance between the metal and the dielectric structure, a condition that prevents the resonance increase of absorption. The high efficiency can be obtained in transverse electric or transverse magnetic polarization and at high incident angles. When cylindrical rods with circular cross-sections are used, the so-called whispering gallery modes can be used to provide the resonances, necessary for the blazing.

[Solifenacin in treatment of the overactive bladder syndrome--diagnosis, clinical management and results]

The overactive bladder syndrome (OAB) is a pathological condition that affects millions of people round the world. Its incidence increases with ageing. The main therapeutic option for OAB nowadays is anti-muscarinic drug therapy.

AIM

To define and implement the diagnostic criteria, clinical guidelines in our country and to evaluate the results of Solifenacin therapy in patients with OAB.

MATERIAL AND METHODS

Along a three years period (2006-2009) 163 OAB patients were analyzed followed and treated. In our group of patients 106 (65.2%) are females and 57 (34.8%)--males. The diagnosis is based mainly on the complaints of the patient, evaluated thoroughly with a detail anamnesis and questionnaires. Urodynamic studies were performed In some of the patients. The efficacy of Solifenacin therapy has been validated with the same methods used in SUNRISE and VENUS studies.

RESULTS AND DISCUSSION

The mean age of female patients in our group is 63.8 years, and 65.6 years for males. The most commonly observed symptoms of OAB are urgency--88.3% and frequency--92%. Urge-incontinence is observed in 48.8% of the cases. Therapy with Solifenacin 5 and 10 mg has alleviated urgency in 82% and urge-incontinence in 88.9%. Mean number of pads used for 24 hours has decreased from 2.6 to 0.4 after therapy.

CONCLUSION

Urgency is the main mandatory symptom for the diagnosis OAB. Therapy with Solifenacin 5 and 10 mg guarantees very good clinical results, and high degree of compliance of the patients.

Malignant melanoma of glans penis and prepuce treated with organ-preserving surgical procedure

The authors present a case of malignant melanoma of glans penis and prepuce. An organ-preserving operative procedure using buccal mucosa was performed with subsequent inguino-femoral modified lymphadenectomy. There was no disease progression during the follow-up period of twelve months.

Total absorption of unpolarized light by crossed gratings

We present both experimental and numerical data showing the absorption of unpolarized, normally incident light by a gold crossed grating having a shallow sinusoidal profile. We show furthermore that the total absorption of unpolarized light can be achieved for an angle of incidence of 30 degrees with a crossed grating having its period adjusted appropriately from the normal incidence case to preserve the plasmonic resonance responsible for the enhanced absorptance. We contrast the process for achieving high absorptance in the principal plane of incidence aligned with the grooves of one of the gratings, with that for the principal plane at 45 degrees to each grating.

Association of platelet function in hypertensive patients with left ventricular hypertrophy, transient myocardial ischemia, and coronary artery disease

The aim of the study was to evaluate how platelet aggregation relates to left ventricular hypertrophy, presence of transient myocardial ischemia and coronary atherosclerosis in essential hypertensive patients. For that purpose platelet aggregation, symptom-limited treadmill-test, echocardiography and coronary angiography were performed in 65 male patients with uncomplicated essential hypertension. Aggregation was monitored both by a turbidometric method and by a method based on real-time estimation of mean aggregate size. Platelet function was also studied in 18 male normotensive subjects. Hypertensive patients with transient myocardial ischemia were characterized by increased platelet sensitivity to adenosine diphosphate, thromboxane A2 mimetic-U46619, serotonin, platelet activating factor and by increased spontaneous aggregability of platelets compared with normotensive subjects and to patients without myocardial ischemia. Platelet aggregation induced by low doses of agonists positively correlated with the degree of left ventricular hypertrophy. This study provides evidence that platelets play an important role in myocardial ischemia. Besides, it was found that platelet activity positively correlated with the degree of left ventricular hypertrophy. This may provide an additional link between left ventricular hypertrophy and coronary heart disease in hypertensive patients.

Case of duplication of the urethra in an adult male, presenting with symptoms of bladder outlet obstruction

Duplication of the urethra is a rare congenital anomaly, usually found in children and adolescents. The authors present a rare case of urethral duplication, presenting in a 58-yr-old man, with symptoms of bladder outlet obstruction.

[Amyloidosis of the urinary tract--case report and review of the literature]

Amyloidosis is a systemic disease which affects a variety of body organs and systems, and is characterized with the deposition of hyalin, eosinophilic, protein-like material in the tissues. Primary amyloidosis of the urinary tract is an extremely rare localization and every published case report represents interest. The authors present a rare case of primary localized amyloidosis of the bladder, which mimics itself as a neoplastic formation and imposes significant diagnostic and therapeutic difficulties. The correct therapeutic approach and the exact histopathologic diagnosis has enabled us to preserve the bladder of the patient and to achieve optimal therapeutic results.

Low polarization dependent diffraction grating for wavelength demultimlexing

A low polarization dependent, high diffraction efficiency grating for wavelength demultiplexer is proposed, manufactured by standard crystallographic etching of Si surface. Light is incident and diffracted inside the wafer, which is covered with reflecting metal. Optimized groove form results in a flat spectral response for TE and TM polarizations.

Maxwell equations in Fourier space: fast-converging formulation for diffraction by arbitrary shaped, periodic, anisotropic media

We establish the most general differential equations that are satisfied by the Fourier components of the electromagnetic field diffracted by an arbitrary periodic anisotropic medium. The equations are derived by use of the recently published fast-Fourier-factorization (FFF) method, which ensures fast convergence of the Fourier series of the field. The diffraction by classic isotropic gratings arises as a particular case of the derived equations; the case of anisotropic classic gratings was published elsewhere. The equations can be resolved either through classic differential theory or through the modal method for particular groove profiles. The new equations improve both methods in the same way. Crossed gratings, among which are grids and two-dimensional arbitrarily shaped periodic surfaces, appear as particular cases of the theory, as do three-dimensional photonic crystals. The method can be extended to nonperiodic media through the use of a Fourier transform.

Photorefractive beam-fanning effect and self-pulsations in coated LiNbO3 slabs

We investigate the dynamical behavior of optical Fabry-Perot resonators consisting of LiNbO3 slabs (x and c cut) that are coated with different (absorbing or lossless) dielectric multilayers deposited on both sides of the slabs. Bistable switching is observed experimentally. The buildup of beam fanning with time leads to destructive interference for a portion of the incident beam, inducing a change in absorption and heating, hence to switching off. As a result, self-pulsations appear whose frequency depends strongly on the input light intensity, the spot size, and the focusing. Switching and self-pulsations are not observed in the case of lossless coatings or for bare LiNbO3 slabs, although strong photorefractive beam fanning is still present. We also study the influence of the incident-beam characteristics (width and focusing) on the beam-fanning process and the pulsating behavior.

Corrugated waveguides as resonance optical filters--advantages and limitations

The role of the excitation of guided waves propagating in a corrugated dielectric waveguide is discussed in view of the resonance anomalies in reflectivity. Narrow-wavelength filtering properties that are due to these sharp anomalies have been a topic of interest for some time, but a proper understanding of device performances requires an analysis of tolerances with respect to the incident-beam collimation and to waveguide losses. Such an analysis is proposed in this paper, and the conclusion is that the incident-beam divergence plays a critical role in reducing the maximum reflectivity for narrow-band filters.

Almost perfect blazing by photonic crystal rod gratings

A periodic array of dielectric rods or holes, known as two-dimensional photonic crystal, is shown to have blazing properties similar to those of classical diffraction gratings. Several different optogeometric configurations are shown numerically to exhibit an almost perfect blazing in the -1st reflected order with a plateaulike spectral dependence in nonpolarized light.

Grating theory: new equations in Fourier space leading to fast converging results for TM polarization

Using theorems of Fourier factorization, a recent paper [J. Opt. Soc. Am. A 13, 1870 (1996)] has shown that the truncated Fourier series of products of discontinuous functions that were used in the differential theory of gratings during the past 30 years are not converging everywhere in TM polarization. They turn out to be converging everywhere only at the limit of infinitely low modulated gratings. We derive new truncated equations and implement them numerically. The computed efficiencies turn out to converge about as fast as in the TE-polarization case with respect to the number of Fourier harmonics used to represent the field. The fast convergence is observed on both metallic and dielectric gratings with sinusoidal, triangular, and lamellar profiles as well as with cylindrical and rectangular rods, and examples are shown on gratings with 100% modulation. The new formulation opens a new wide range of applications of the method, concerning not only gratings used in TM polarization but also conical diffraction, crossed gratings, three-dimensional problems, nonperiodic objects, rough surfaces, photonic band gaps, nonlinear optics, etc. The formulation also concerns the TE polarization case for a grating ruled on a magnetic material as well as gratings ruled on anisotropic materials. The method developed is applicable to any theory that requires the Fourier analysis of continuous products of discontinuous periodic functions; we propose to call it the fast Fourier factorization method.

Differential method applied for photonic crystals

The classic differential method is applied for modeling the diffraction of light from two-dimensional photonic crystals that consist of dielectric cylindrical objects. Special attention is paid to mutual interpenetration of consecutive layers. Two algorithms for dealing with a stack of repetitive layers are discussed, namely, the eigenvalue technique and the S-matrix algorithm. Their advantages and limitations are analyzed, and times required for their implementation are compared.

Differential theory for diffraction gratings: a new formulation for TM polarization with rapid convergence

A new formulation of the differential method in TM polarization, based on correct representation of truncated Fourier series of products of discontinuous functions, is proposed. Although the derived equations are more complicated than in the classical formulation, the convergence rate with respect to the truncation parameter (with the number of diffraction orders taken into account) is much faster for arbitrary grating profiles, approaching the convergence rate in TE polarization. Numerical examples are presented for dielectric and metallic sinusoidal gratings with a 100% modulation ratio.

Inhibition of induced and spontaneous platelet aggregation by destabilase from medicinal leech

Destabilase, endo-epsilon-(gamma-Glu)-Lys isopeptidase from the medicinal leech, inhibits arterial thrombus formation in rats. Inhibition of platelet aggregation was supposed to be one of the main mechanisms of this phenomenon. To elucidate this question highly purified destabilase preparations were used. Aggregation was monitored both by a turbidometric method and by a method based on real-time estimation of mean aggregate size. Spontaneous aggregation of human platelets was completely blocked by destabilase. At 5 microM ADP maximal inhibition was 63%. Aggregation induced by PAF (100 nM) and collagen (0.1 mg/ml) was inhibited in the presence of destabilase by 50 and 65%, respectively. This enzyme does not activate adenylate cyclase but inhibits it. We suggest that destabilase interacts with high-affinity binding sites on the platelet plasma membrane, thus providing an anti-aggregating effect. This idea coincides with the data that destabilase primary structure has high homology with some adhesive proteins.