EGFR ligands and DNA repair genes: genomic predictors of complete response after capecitabine-based chemoradiotherapy in locally advanced rectal cancer.

Epidermal growth factor receptor (EGFR) activation by radiation leads to increased cell proliferation and acts as a radioresistance mechanism. Neoadjuvant chemoradiation is the standard of care for locally advanced rectal cancer, and to date, no biomarkers of response have been found. We analyzed polymorphisms in the EGFR and its ligands, DNA repair genes and the thymidylate synthase in 84 stages II and III rectal cancer patients treated with neoadjuvant capecitabine plus radiotherapy. The rs11942466 polymorphism in the amphiregulin (AREG) gene region was associated with a pathological complete response (ypCR) (odds ratio: 0.26; 95% confidence interval: 0.06-0.79; P=0.014). The rs11615 C>T polymorphism in the ERCC1 gene also correlated with the ypCR as no patients with a C/C genotype achieved ypCR; P=0.023. This is the first work to propose variants within the AREG and the ERCC1 genes as promising predictive biomarkers of ypCR in rectal cancer.

HYPONYCHIUM ABNORMALITIES Congenital Aberrant Hyponychium vs. Acquired Pterygium Inversum Unguis vs. Acquired Reversible Extended Hyponychium: a proposed classification based on origin, pathology and outcome.

BACKGROUND: Pterygium Inversum Unguis (PIU) is a wing-like extended hyponychium associated with the absence of the distal groove. Although a rare condition, it has been described with different names, confusing both the investigator and the reader. OBJECTIVE: We propose a new nomenclature based on tissue origin and pathology, to account for these conditions. 1) Congenital Aberrant Hyponychium 2) Acquired Pterygium Inversum Unguis 3) Acquired Reversible Extended Hyponychium. MAIN OBSERVATIONS: We report a case of a 19-year-old male, with epidermal pigmentation abnormalities, who had painful fingertips of both index fingers and thumbs since he was 13. He therefore let his finger nails grow very long, minimizing painful contact with the hyponychium. Removal of the aberrant hyponychium revealed glomus bodies aggregates with increased nerve fibers. Subsequently after excision of the hyponychium, his pain was resolved. SUMMARY: Congenital, transient or permanent changes in the hyponychium should be named and classified according to tissue origin to avoid nomenclature confusion.

Intergenic polymorphisms in the amphiregulin gene region as biomarkers in metastatic colorectal cancer patients treated with anti-EGFR plus irinotecan.

In the epidermal growth factor receptor (EGFR) pathway, polymorphisms in EGFR and its ligand EGF have been studied as biomarkers for anti-EGFR treatment. However, the potential pharmacogenetic role of other EGFR ligands such as amphiregulin (AREG) and epiregulin (EREG) has not been elucidated. We studied 74 KRAS and BRAF wild-type metastatic colorectal cancer patients treated with anti-EGFR plus irinotecan. Twenty-two genetic variants in EGFR, EGF, AREG and EREG genes were selected using HapMap database and literature resources. Three tagging single-nucleotide polymorphisms in the AREG gene region (rs11942466 C>A, rs13104811 A>G, and rs9996584 C>T) predicted disease control in the multivariate analyses. AREG rs11942466 C>A and rs9996584 C>T were also associated with overall survival (OS). The functional polymorphism, EGFR rs712829 G>T, was associated with progression-free and OS. Our findings support that intergenic polymorphisms in the AREG gene region might help to identify colorectal cancer patients that will benefit from irinotecan plus anti-EGFR therapy.

The beginnings of dermatopathology and dermatologic microbiology in Spain.

Crisóstomo Martínez from Valencia was a pioneering microscopist in 17th-century Europe. The first microscopic representations of skin in Spain appeared in an 18th-century work by Martín Martínez. Microbiology and histopathology progressed considerably in the late 19th century thanks to anatomists like Maestre de San Juan and surgeons like Federico Rubio Galí. The first Spanish pathologist to specialize in dermatology was Antonio Mendoza, a colleague of José Eugenio de Olavide at the Hospital San Juan de Dios in Madrid. Claudio Sala and Juan de Azúa also made significant contributions, including the description of pseudoepithelioma. Several disciples of Santiago Ramón y Cajal and Jorge FranciscoTello, such as Lorenzo Ruiz de Arcaute and Guillermo de la Rosa King, consolidated the dermatology laboratory, but the Civil War sent many into exile or deprived them of their professional status. Juan Rubió in Barcelona and Julio Rodríguez Puchol in Madrid were the immediate predecessors of today's dermatopathologists.

Nightlife, verbal and physical violence among young European holidaymakers: what are the triggers?

OBJECTIVES: There is an established relationship between nightlife, substance use and violence. This study investigated this relationship when people are on holiday, and explored the differences in experiences between physical and verbal violence. STUDY DESIGN: A survey of young tourists at seven airport departure areas in Southern European resorts. METHODS: Questionnaires from 6502 British and German tourists were analysed exploring demographics, violence (verbal and physical), substance use, and reasons for resort and venue selection. RESULTS: Over two-thirds of respondents reported being drunk on their holiday, 12.4% had been involved in arguments and 2.9% had been involved in fights. Logistic regression highlighted more violence amongst visitors to Mallorca [arguments: adjusted odds ratio (AOR) 2.7; fights: AOR 2.0] compared with those visiting Portugal, males (arguments: AOR 1.3; fights: AOR 1.7), those who had used illicit drugs (arguments: AOR 1.5; fights: AOR 2.9), those who had been in fights at home in the last 12 months (arguments: AOR 2.2; fights AOR 2.9), and those who had frequently been drunk abroad (arguments: AOR 2.4; fights: AOR 2.5). Those aged 16-19 years, visiting Italy or Crete, who were drunk for fewer than half of the days of their stay, and who chose bars because they were frequented by drunk people were more likely to report having an argument. Fights were associated with cannabis use and were negatively associated with choosing bars with a friendly atmosphere. Economic status or frequency of visiting bars had no relationship with arguments or fights. CONCLUSIONS: Understanding and addressing the variables involved in violence when holidaying abroad is critical in targeting appropriate health promotion and harm reduction measures.

Quercetin improves and protects Calu-3 airway epithelial barrier function.

Introduction: In light of the impact of airway barrier leaks in COVID-19 and the significance of vitamin D in COVID-19 outcomes, including airway barrier protection, we investigated whether the very common dietary flavonoid quercetin could also be efficacious in supporting airway barrier function. Methods: To address this question, we utilized the widely used airway epithelial cell culture model, Calu-3. Results: We observed that treating Calu-3 cell layers with quercetin increased transepithelial electrical resistance while simultaneously reducing transepithelial leaks of 14C-D-mannitol (Jm) and 14C-inulin. The effects of quercetin were concentration-dependent and exhibited a biphasic time course. These effects of quercetin occurred with changes in tight junctional protein composition as well as a partial inhibition of cell replication that resulted in decreased linear junctional density. Both of these effects potentially contribute to improved barrier function. Quercetin was equally effective in reducing the barrier compromise caused by the pro-inflammatory cytokine TNF-α, an action that seemed to derive, in part, from reducing the elevation of ERK 1/2 caused by TNF-α. Discussion: Quercetin improved Calu-3 barrier function and reduced TNF-α-induced barrier compromise, mediated in part by changes in the tight junctional complex.

Comparative studies of the sensitivities of sparse and full geometries of Total-Body PET scanners built from crystals and plastic scintillators.

BACKGROUND: Alongside the benefits of Total-Body imaging modalities, such as higher sensitivity, single-bed position, low dose imaging, etc., their final construction cost prevents worldwide utilization. The main aim of this study is to present a simulation-based comparison of the sensitivities of existing and currently developed tomographs to introduce a cost-efficient solution for constructing a Total-Body PET scanner based on plastic scintillators. METHODS: For the case of this study, eight tomographs based on the uEXPLORER configuration with different scintillator materials (BGO, LYSO), axial field-of-view (97.4 cm and 194.8 cm), and detector configurations (full and sparse) were simulated. In addition, 8 J-PET scanners with different configurations, such as various axial field-of-view (200 cm and 250 cm), different cross sections of plastic scintillator, and multiple numbers of plastic scintillator layers (2, 3, and 4), based on J-PET technology have been simulated by GATE software. Furthermore, Siemens' Biograph Vision has been simulated to compare the results with standard PET scans. Two types of simulations have been performed. The first one with a centrally located source with a diameter of 1 mm and a length of 250 cm, and the second one with the same source inside a water-filled cylindrical phantom with a diameter of 20 cm and a length of 183 cm. RESULTS: With regards to sensitivity, among all the proposed scanners, the ones constructed with BGO crystals give the best performance ([Formula: see text] 350 cps/kBq at the center). The utilization of sparse geometry or LYSO crystals significantly lowers the achievable sensitivity of such systems. The J-PET design gives a similar sensitivity to the sparse LYSO crystal-based detectors while having full detector coverage over the body. Moreover, it provides uniform sensitivity over the body with additional gain on its sides and provides the possibility for high-quality brain imaging. CONCLUSION: Taking into account not only the sensitivity but also the price of Total-Body PET tomographs, which till now was one of the main obstacles in their widespread clinical availability, the J-PET tomography system based on plastic scintillators could be a cost-efficient alternative for Total-Body PET scanners.

Efficiency determination of J-PET: first plastic scintillators-based PET scanner.

BACKGROUND: The Jagiellonian Positron Emission Tomograph is the 3-layer prototype of the first scanner based on plastic scintillators, consisting of 192 half-metre-long strips with readouts at both ends. Compared to crystal-based detectors, plastic scintillators are several times cheaper and could be considered as a more economical alternative to crystal scintillators in future PETs. JPET is also a first multi-photon PET prototype. For the development of multi-photon detection, with photon characterized by the continuous energy spectrum, it is important to estimate the efficiency of J-PET as a function of energy deposition. The aim of this work is to determine the registration efficiency of the J-PET tomograph as a function of energy deposition by incident photons and the intrinsic efficiency of the J-PET scanner in detecting photons of different incident energies. In this study, 3-hit events are investigated, where 2-hits are caused by 511 keV photons emitted in [Formula: see text] annihilations, while the third hit is caused by one of the scattered photons. The scattered photon is used to accurately measure the scattering angle and thus the energy deposition. Two hits by a primary and a scattered photon are sufficient to calculate the scattering angle of a photon, while the third hit ensures the precise labeling of the 511 keV photons. RESULTS: By comparing experimental and simulated energy distribution spectra, the registration efficiency of the J-PET scanner was determined in the energy deposition range of 70-270 keV, where it varies between 20 and 100[Formula: see text]. In addition, the intrinsic efficiency of the J-PET was also determined as a function of the energy of the incident photons. CONCLUSION: A method for determining registration efficiency as a function of energy deposition and intrinsic efficiency as a function of incident photon energy of the J-PET scanner was demonstrated. This study is crucial for evaluating the performance of the scanner based on plastic scintillators and its applications as a standard and multi-photon PET systems. The method may be also used in the calibration of Compton-cameras developed for the ion-beam therapy monitoring and simultaneous multi-radionuclide imaging in nuclear medicine.

Methotrexate consolidation treatment according to pharmacogenetics of MTHFR ameliorates event-free survival in childhood acute lymphoblastic leukaemia.

Recent advances in treatment for childhood acute lymphoblastic leukaemia (ALL) have significantly increased outcome. High-dose methotrexate (MTX) is the most commonly used regimen during the consolidation period, but the optimal dose remains to be defined. We investigated the usefulness of the MTHFR genotype to increase the MTX dosage in the consolidation phase in 141 childhood ALL patients enrolled in the ALL/SHOP-2005 protocol. We also investigated the pharmacogenetic role of polymorphisms in genes involved in MTX metabolism on therapy-related toxicity and survival. Patients with a favourable MTHFR genotype (normal enzymatic activity) treated with MTX doses of 5 g m⁻² had a significantly lower risk of suffering an event than patients with an unfavourable MTHFR genotype (reduced enzymatic activity) that were treated with the classical MTX dose of 3 g m⁻² (P=0.012). Our results indicate that analysis of the MTHFR genotype is a useful tool to optimise MTX therapy in childhood patients with ALL.

A genotype-directed phase I-IV dose-finding study of irinotecan in combination with fluorouracil/leucovorin as first-line treatment in advanced colorectal cancer.

BACKGROUND: Infusional fluorouracil/leucovorin (FU/LV) plus irinotecan (FOLFIRI) is one of the standard first-line options for patients with metastatic colorectal cancer (mCRC). Irinotecan is converted into 7-ethyl-10-hydroxycamptothecin (SN-38) by a carboxylsterase and metabolised through uridine diphosphate glucuronosyl transferase (UGT1A1). The UGT1A1*28 allele has been associated with the risk of developing severe toxicities. The present trial was designed to define the maximum tolerated dose according to UGT1A1 genotype. This report focuses on the results of tolerance to different escalated doses of FOLFIRI first-line of chemotherapy. PATIENTS AND METHODS: Patients undergoing first-line treatment for mCRC and eligible for treatment with FOLFIRI were classified according to UGT1A1 genotype. A total of 94 patients were eligible for dose escalation of irinotecan. The starting dose of biweekly irinotecan was 180 mg m(-2) for the *1/*1, 110 mg m(-2) for the *1/*28 and 90 mg m(-2) for the *28/*28 genotypes. RESULTS: The dose of irinotecan was escalated to 450 mg m(-2) in patients with the *1/*1 genotype, to 390 mg m(-2) in those with the *1/*28 genotype and to 150 mg m(-2) in those with the *28/*28 genotype. Neutropenia and diarrhoea were the most common grade 3 or 4 toxicities. CONCLUSIONS: Our results demonstrated that the recommended dose of 180 mg m(-2) for irinotecan in FOLFIRI is considerably lower than the dose that can be tolerated for patients with the UGT1A1 *1/*1 and *1/*28 genotypes. The maximum tolerable dose (MTD) in patients with a high-risk UGT1A1 *28/*28 genotype is 30% lower than the standard dose of 180 mg m(-2).

[Favorable outcome of acute respiratory failure caused by H1N1 virus infection in critical patients]. / Evolución favorable de insuficiencia respiratoria aguda por gripe A (H1N1) en pacientes críticos.

OBJECTIVE: To describe clinical features, treatment, complications, and outcomes in cases of acute respiratory distress syndrome (ARDS) caused by H1N1 virus infection treated in an anesthesia department's recovery unit. MATERIALS AND METHODS: Patients were those admitted to our recovery unit with H1N1 virus infection confirmed by reverse transcription polymerase chain reaction, nasopharyngeal swabs, and/or bronchial aspirates. RESULTS: From August to December 2009, we admitted 8 patients (mean age, 43 [range 24-46] years) to the recovery unit. Six were men, three were of Roma origin, and 50% had concomitant diseases. Mean (SD) time from symptom onset to admittance to the recovery unit was 3.25 (1.6) days. Four had received broad-spectrum antibiotics during the last month. Six had primary viral pneumonia, 1 had secondary bacterial pneumonia and 1 had exacerbated chronic obstructive pulmonary disease. Three had bacterial coinfection, and 4 developed multiple organ dysfunction syndrome and ARDS, requiring mechanical ventilation (5.75 [3.10] days) and vasopressors (4.25 [3.40] days). The mean ratio of PaO2 to the inspired oxygen fraction at admittance was 93.8 (31.0) and the mean positive end-expiratory pressure applied was 14.5 (4.2) cm H2O. Oseltamivir was administered (150 mg/12 h) with a mean delay of 3.88 (1.64) days. Additional inhaled zanamivir was administered on day 7 to a patient with a positive viral culture. Antibiotics were prescribed following the guidelines of the American Thoracic Society and Infectious Diseases Society of America for community-acquired pneumonia (50% of the cases) and healthcare-associated pneumonia (50%). Seven subjects received 1 mg x kg(-1) x day(-1) of methylprednisolone. Patients with mechanical ventilation required continuous insulin infusion (maximum daily dosage, 87 [50.3] IU) to maintain blood glucose levels between 80 and 150 mg x dL(-1). Patients under mechanical ventilation achieved a negative net fluid balance. All patients survived and were discharged from the recovery unit in 7.38 (4.83) days (range, 2-16 days) and subsequently discharged home in 13.25 (7.74) days (range, 6-27 days). All were alive 60 days after discharge. CONCLUSION: In this series of critically ill patients with H1N1 virus infection that was initially life-threatening, all responded favorably to conventional treatment and could be discharged.

[History of Actas Dermo-Sifiliográficas, part I: 1909-1959]. / Historia de Actas Dermo-Sifiliográficas (I): 1909-1959.

Actas Dermo-Sifiliográficas was born in May 1909. At first, issues appeared in step with the academic year, but publication began to follow the calendar year in 1957. Volume 18 was skipped in 1926-7 in an effort to correct confusion in the numbering of volumes and pages of earlier issues. October 1928 saw the journal grow from 6 issues per year to 9. Although the Spanish Civil War brought publication to a halt during the 1936-7 academic year, Actas Dermo-Sifiliográficas was one of the first Spanish scientific journals to recover from the conflict. The initial print run of 100 copies was increased to 700 after the war. The content evolved over time: while originally conceived to provide a strict account of sessions of the Spanish Academy of Dermatology and Venereology (AEDV) -originally known as the Spanish Academy of Dermatology and Syphilology- the journal gradually came to include review articles, case reports, a section summarizing the content of international journals, news and various other types of writing. The editorial board and the association's board of directors were one and the same for many years. According to the earliest charter, the editor-in-chief was also the president of the association and the associate editor was the association's vice-president. The subjects of articles provide a faithful portrait of how the specialty has changed. Syphilis, a main concern before the introduction of penicillin in the 1940s, was sidelined afterwards. The appearance of 20th-century pharmaceuticals such as salvarsan, sulfa drugs, thiazides, and corticosteroids were soon reflected in the number of articles describing their use. Certain original contributions by Spanish authors to international dermatology first appeared in Actas Dermo-Sifiliográficas. Examples are Azúa's description of pseudoepithelioma and Covisa and Bejarano's of chancriform pyoderma. Volume 50 (1959), which included accounts of the 50th anniversary of the association and the journal, closed with a biography of Enrique Álvarez Sainz de Aja, the only founding member still living at that time.

Multiple Perianal Ulcers Related to Use of a Hemorrhoidal Ointment With the Active Ingredients Triamcinolone Acetonide, Lidocaine, and Pentosan Polysulfate Sodium: A Series of 11 Spanish Patients. / Múltiples úlceras perianales en relación con el uso de una pomada antihemorroidal con acetónido de triamcinolona, lidocaína y pentosano polisulfato sódico como principios activos: una serie de 11 pacientes españoles.

The development of perianal ulcers related to the use of a hemorrhoidal ointment has not been reported in the literature. We describe a series of 11 patients who were treated for perianal ulcers in 10 Spanish hospitals after they used the same ointment containing the active ingredients triamcinolone acetonide, lidocaine, and pentosan polysulfate sodium. No prior or concomitant conditions suggesting an alternative cause for the condition could be identified, and after the patients stopped using the ointment, their ulcers cleared completely in 8 weeks on average. This case series shows the damage that can be caused by an over-the-counter pharmaceutical product used without medical follow-up. It also illustrates the need to ask patients with perianal ulcers about any topical agents used before the lesions appeared.

Impact of CYP2D6 polymorphisms in tamoxifen adjuvant breast cancer treatment.

The aim of this study is to evaluate the impact of CYP2D6 genotyping in predicting disease-free survival and toxicity in breast cancer patients treated with adjuvant tamoxifen. DNA from 91 patients was genotyped using the AmpliChip CYP450 GeneChip, Roche that facilitates the classification of individuals by testing 27 alleles. When patients were grouped into group 1 (*4/*4, *4/*41, *1/*5 and *2/*5) and group 2 (the remaining genotypes), a significant difference in disease-free survival (DFS) was observed between groups (P = 0.016). The mean DFS in group 1 was 95 months in contrast with 119 months in group 2. No significant relationship was found between the CYP2D6 genotype classification and severe, mild or no toxicity (P = 0.2). Nevertheless, severe, and mild toxicity was more frequent among poor metabolizer patients than in patients with a normal metabolizer pattern (18.8 and 43.8% vs. 10.7 and 36%, respectively). In breast cancer, patients treated with adjuvant tamoxifen, non-functional and severely impaired CYP2D6 variants are associated with a worse DFS and with a higher frequency of severe and mild toxicities. Larger studies of the CYP2D6 genotype-clinical outcomes association are needed to complement initial results.

3 D characterization of gold nanoparticles supported on heavy metal oxide catalysts by HAADF-STEM electron tomography.

Living on the edge: Three-dimensional reconstructions from electron tomography data recorded from Au/Ce(0.50)Tb(0.12)Zr(0.38)O(2-x) catalysts show that gold nanoparticles (see picture; yellow) are preferentially located on stepped facets and nanocrystal boundaries. An epitaxial relationship between the metal and support plays a key role in the structural stabilization of the gold nanoparticles.

Pharmacogenetic prediction of clinical outcome in advanced colorectal cancer patients receiving oxaliplatin/5-fluorouracil as first-line chemotherapy.

To determine whether molecular parameters could be partly responsible for resistance or sensitivity to oxaliplatin (OX)-based chemotherapy used as first-line treatment in advanced colorectal cancer (CRC). We studied the usefulness of the excision repair cross-complementing 1 (ERCC1), xeroderma pigmentosum group D (XPD), XRCC1 and GSTP1 polymorphisms as predictors of clinical outcome in these patients. We treated 126 CRC patients with a first-line OX/5-fluorouracil chemotherapeutic regimen. Genetic polymorphisms were determined by real-time PCR on an ABI PRISM 7000, using DNA from peripheral blood. Clinical response (CR), progression-free survival (PFS) and overall survival (OS) were evaluated according to each genotype. In the univariate analysis for CR, ERCC1-118 and XPD 751 polymorphisms were significant (P=0.02 and P=0.05, respectively). After adjustment for the most relevant clinical variables, only ERCC1-118 retained significance (P=0.008). In the univariate analysis for PFS, ERCC1-118 and XPD 751 were significant (P=0.003 and P=0.009, respectively). In the multivariant analysis, only the XPD 751 was significant for PFS (P=0.02). Finally, ERCC1-118 and XPD 751 polymorphisms were significant in the univariate analysis for OS (P=0.006 and P=0.015, respectively). Both genetic variables remained significant in the multivariate Cox survival analysis (P=0.022 and P=0.03). Our data support the hypothesis that enhanced DNA repair diminishes the benefit of platinum-based treatments.

Transcription factor-binding sites in the thymidylate synthase gene: predictors of outcome in patients with metastatic colorectal cancer treated with 5-fluorouracil and oxaliplatin?

The identification of clinical and genetic parameters to predict the outcome in advanced colorectal cancer is a key issue in the management of this disease. We ascertained whether the clinical determinants of survival defined in a large cohort of patients treated with 5-fluorouracil (5-FU) (European Organization for the Research and Treatment of Cancer, EORTC model) also apply to 109 colorectal cancer patients receiving a therapy including oxaliplatin/5-FU as their first-line treatment. Our results confirm the considerable discriminatory power of the clinical model proposed in patients treated with a combined chemotherapy regimen. With the aim of identifying additional genetic prognostic parameters, we determined whether the polymorphisms in the promoter region of the thymidylate synthase (TS) gene that modifies the number of operative binding sites of a transcription factor (USF) could predict the clinical outcome of our patients and complement the EORTC clinical model. Our results indicate that this new genetic parameter (the number of USF-binding sites) could be considered when evaluating the role of TS genotype in the efficacy of the 5-FU-based regimens. Further, confirmatory studies aimed at evaluating the effect of the number of binding sites of transcription factors for selecting 5-FU-treated patients are warranted.

[The impact of different renal function measuring methods on the dosages of meropenem, piperacillin/tazobactam and cefepime in critically ill patients]. / Impacto de distintos métodos de estimación de la función renal en la dosificación de meropenem, piperacilina/tazobactam y cefepima en pacientes críticos.

OBJECTIVE: Assesment of dosage deviations of three ss-lactam antibiotics eliminated through the kidneys (meropenem, piperacillin/tazobactam and cefepime) by comparison of two prediction formulae, Cockroft-Gault (CG) and Modification of Diet in Renal Disease (MDRD) with 24 h urinary creatinine clearance (CrCl(24h)), as a reference method. METHOD: 125 samples of 61 critically ill patients (each one with CG, MDRD y CrCl(24h) values) were classified in one of the five stages of the National Kidney Foundation (NKF) according to CrCl(24h). Dosage discrepancies for each antibiotic based on CG y MDRD were studied in reference to CrCl(24h) by percentage agreement and weighted kappa. At each of the NKF stages, daily dosage differences (Delta=DosisCG-DosisCrCl(24h); Delta=DosisMDRD-DosisCrCl(24h)) and percentage of samples with dosage discrepancies by CG and MDRD in reference to CrCl(24h) were calculated. RESULTS: There were no statistically significant differences between the two prediction formulae in respect to CrCl(24h), achieving good degrees of concordance. Deviation percentages fluctuated between 15.2% and 28% and occurred mainly by underdosing on stages 1 and 2 and by overdosing on stages 4 and 5. CONCLUSIONS: The two renal function prediction formulae can be indistinctly used to optimize the ss-lactam antibiotics dose regimen, CG being the easiest one.

Revisiting McMillan's theory of the smectic A phase.

We consider the full solution of McMillan's molecular model of the smectic A phase within the mean-field approximation, expressing the free energy (or the effective one-particle mean-field energy) of the model in terms of an infinite set of orientational and translational order parameters. The general formalism reduces to the usual McMillan theory (hereafter referred to as McMillan's approximation) when second- and higher-order harmonics in the Fourier expansion are neglected, which leads to a description of the smectic phase in terms of the leading order parameters. The effects of such a truncation on the location of the tricritical nematic-smectic A point have been previously considered by Longa (1986 J. Chem. Phys. 85 2974). A quantitative analysis to assess the relative importance of the neglected terms in the description of the smectic phase and its various transitions is reported. It is shown that McMillan's approximation underestimates both orientational and translational order, and leads to values of the transition entropies smaller than those resulting from the full expansion.