AI-Based Homology Modelling of Fatty Acid Transport Protein 1 Using AlphaFold: Structural Elucidation and Molecular Dynamics Exploration

Fatty acid transport protein 1 (FATP1) is an integral transmembrane protein that is involved in facilitating the translocation of long-chain fatty acids (LCFA) across the plasma membrane, thereby orchestrating the importation of LCFA into the cell. FATP1 also functions as an acyl-CoA ligase, catalyzing the ATP-dependent formation of fatty acyl-CoA using LCFA and VLCFA (very-long-chain fatty acids) as substrates. It is expressed in various types of tissues and is involved in the regulation of crucial signalling pathways, thus playing a vital role in numerous physiological and pathological conditions. Structural insight about FATP1 is, thus, extremely important for understanding the mechanism of action of this protein and developing efficient treatments against its anomalous expression and dysregulation, which are often associated with pathological conditions such as breast cancer. As of now, there has been no prior prediction or evaluation of the 3D configuration of the human FATP1 protein, hindering a comprehensive understanding of the distinct functional roles of its individual domains. In our pursuit to unravel the structure of the most commonly expressed isoforms of FATP1, we employed the cutting-edge ALPHAFOLD 2 model for an initial prediction of the entire protein's structure. This prediction was complemented by molecular dynamics simulations, focusing on the most promising model. We predicted the structure of FATP1 in silico and thoroughly refined and validated it using coarse and molecular dynamics in the absence of the complete crystal structure. Their relative dynamics revealed the different properties of the characteristic FATP1.

Efficiency of Invisalign First® to promote expansion movement in mixed dentition: a retrospective study and systematic review

Aim

The present study aimed: i) to retrospectively evaluate the expansion movement predicted by the Clincheck® software and the achieved expansion using Invisalign First® in children needing maxillary expansion to correct malocclusions; and ii) to critically compare these clinical results with the outcomes obtained for maxillary expansion using conventional removable and cemented expanders.

Material and Methods

The 3D digital models of the dental arches of 24 children undergoing orthodontic treatment exclusively with Invisalign First® aligners between 2018 and 2021 were sequentially selected for this study. Three digital models were analysed: pre-treatment (P0), the Clincheck®-predicted tooth positions (P1), and post-treatment (P2) models. The maxillary dental arch width and expansion efficiency were measured andcalculated. An in-depth review of the available literature on maxillary expansion was performed following PRISMA guidelines.

Results

Invisalign First® was able to achieve a total effectiveness of maxillary expansion of 62.6%, compared to the predicted movement. Similarly, the total effectiveness of mandibular expansion was 61.6%.

Conclusions

Our data shows that Invisalign First® system can increase the arch width with maxillary expansion effectiveness, providing similar results to those achieved with conventional removable appliances. However, neither Invisalign First® aligners nor conventional removable expanders are as much efficient as cemented-retained appliances.

Serum fatty acid transport protein 1 in women with and without breast cancer

Introduction and Aim: Obesity influences the serum lipid profiles leading to dysregulation of lipid metabolism in which fatty acid transporter like FATP 1 (Fatty acid transport protein 1) are recognized to play a key role in BC progression. Aim of the present study is to compare FATP1 levels in women with and without BC.   Materials and Methods:  In this case-control study, 50 BC and 50 control subjects were recruited. Serum was separated from the blood and baseline characteristics like height, weight, age and BMI were noted for all the subjects. Lipid profile and serum level of FATP1 was estimated using a commercially available kit. P<0.05 was found as statistically significant.   Results: The serum FATP1 levels in subjects with breast cancer differed significantly between the case and control. TC, TAG, HDL-C, LDL-C, and VLDL-C differed between two groups and were statistically significant. Further, serum FATP1 levels in subjects with BC were compared based on the status of the receptor showed a significant difference in TG, VLDL-C and serum FATP1.Correlating the serum FATP1 levels with baseline characteristics and lipid profiles in subjects with BC, age showed a positive correlation with serum FATP1 levels. Correlation of FATP1 with different receptor status in subjects with BC showed a positive correlation between FATP1 and VLDL in ER+/PR-/HER2+ receptor status, FATP1 and HDL-C showed a positive correlation in triple-negative BC.   Conclusion: Though extensive research on breast cancer is underway, Study reports on serum level of FATP1 in BC are scarce. Current study demonstrates the importance of serum levels of FATP1 in BC. Further study on the molecular regulation of FATP1 in BC will add to the knowledge, and findings of the study implicates for utilizing FATP1 as a biomarker in BC.

Phytochemical profiling, total flavonoid, total phenolic content and in-vitro antioxidant evaluation of Citrus maxima extract

Introduction and Aim: Citrus fruits are rich in polyphenolic compounds. The conventional medical system has utilized the fruit’s entire composition including the peel for its diverse biological functions. With this, the study aimed to assess and compare the phytochemical, in-vitro antioxidant analysis as well as polyphenol and flavonoid content of Citrus maxima juice, aqueous and ethanolic extracts of its pulp and peel.   Materials and Methods: Qualitative phytochemical screening, total phenolic content and total flavonoid content and different in-vitro antioxidant assays like total antioxidant capacity (TAC), Ferric reducing antioxidant power assay (FRAP), 2,2-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging assay were carried out to evaluate the                in-vitro antioxidant potential in the juice, aqueous and ethanolic extract of pulp and peel of C. maxima. Gas chromatography–Mass spectrometry (GC–MS) analysis was performed in the peel ethanolic extract to identify the compounds present.   Results: Preliminary phytochemical analysis revealed the presence of triterpenoids and steroids, glycosides, alkaloids, flavonoids, carbohydrates and vitamin C in all the C. maxima crude extracts. Tannins were present only in pulp of ethanol extract and in both aqueous and ethanol extracts of peel. Resins were present in the juice and ethanol extract of pulp and peel. The total phenol and total flavonoid content was comparatively higher in ethanolic extracts of peel. All the extracts showed dose-dependent free radical scavenging activity. The reducing potential of the C.maxima extractives increased with the increase in its concentration. GC-MS analysis of ethanolic peel extract identified key constituents with pharmacological effects. The ethanolic peel extract showed good antioxidant activity and free radical scavenging activity when compared to other extracts.   Conclusion: The results indicated that ethanolic peel extract of Citrus maxima revealed the highest presence of polyphenolic compounds, which are secondary plant metabolites with potential antioxidant activity.

Cardiovascular disease in an intensive care unit: patterns of an often fatal omen

Background

Care for the critically ill patient with Cardiovascular Disease (CVD) requires a unique management approach, as the theoretical critical threshold for decompensation is lower and inherent adaptive mechanisms may be compromised. We aimed to characterize the prognostic impact of CVD in patients admitted to an Intensive Care Unit (ICU).

Methods

We performed a cohort study of consecutive patients admitted to an ICU from January to December 2019. Patients were stratified as follows: (1) established CVD – presence of either atrial fibrillation, heart failure, coronary artery disease and/or peripheral artery disease; (2) at higher risk of CVD – known arterial hypertension, dyslipidemia, diabetes mellitus and/or current smoking, in the absence of established CVD; and (3) at lower risk of CVD – i.e. none of the above. The co-primary endpoints were all-cause death in ICU and death during index hospitalization.

Results

During 2019, there were 334 admissions in ICU, comprising a total of 296 patients (mean age 67±15 years, 58.1% male). Overall, 69 (23.3%) and 108 (36.5%) died in ICU and during index hospitalization, respectively. Compared to patients at lower risk of CVD, those at higher CVD risk or with established CVD had markers of more severe disease, as noted by higher risk scores (e.g., SAPS-II 35.0±20.0 vs. 43.5±22.3 vs. 52.6±20.0; p&lt;0.001), higher rates of mechanical ventilation (41.5 vs. 57.3 vs. 63.9%; p=0.020), shock during ICU stay (34.0 vs. 52.7 vs. 66.9%; p&lt;0.001) and acute kidney injury (26.4 vs. 35.5 vs. 57.9%; p&lt;0.001), respectively, as well as higher death rates in ICU (5.7 vs. 21.8 vs. 31.6%; p=0.001) and index hospitalization (9.4 vs. 37.3 vs. 46.6%; p&lt;0.001). In multivariate analysis, adjusted for age and cause of admission, established CVD independently predicted the risk of all-cause death in ICU (HR: 2.084; 95% CI: 1.136–3.823; p=0.018) and during index hospitalization (HR 1.712; CI: 1.009–2.889; p=0.046). The analysis for the group of patients at higher risk of CVD yielded similar results to the abovementioned.

Conclusion

Roughly 4 in every 5 patients admitted in ICU were at risk of or had established CVD. The presence of either of the above independently predicted a two- to three-fold higher risk of death during hospitalization. Our findings emphasize the considerable burden of CVD in ICU and underscore the importance of comprehensive management of the complex critically ill patient.

Funding Acknowledgement

Type of funding sources: None.

Chronic heart failure in intensive care unit: can we accurately predict the risk?

Background

Severity of disease scoring systems, namely the Simplified Acute Physiology Score (SAPS) and Acute Physiology and Chronic Health Evaluation (APACHE), are widely used to predict mortality in Intensive Care Units (ICU). Yet, neither score includes chronic HF in their model. We aimed to evaluate whether these scores perform well in risk prediction of death of patients previously diagnosed with heart failure (HF).

Methodology

This is a single-center retrospective cohort of patients admitted to an ICU in 2019. Those whose admission lasted &lt;24 hours were excluded from analysis. The SAPS II and APACHE II scores were calculated using data from the first 24 hours of ICU admission, imputing the worst variable obtained within this timeframe. HF was defined according to the ESC recommendations. In order to assess the performance of the scores, Receiver Operating Characteristic (ROC) Curves were used to predict the risk of death in ICU in HF compared to the non-HF population.

Results

A total of 267 patients were hospitalized in ICU for a period over 24 hours in 2019 (mean age 67±16 years; 58.8% males; 21.7% with chronic HF; 33.7% admitted for sepsis). Compared to patients without HF, those with chronic HF were older (74±13 vs. 65±16 years; p&lt;0.001) and had higher risk scores (mean SAPS II: 43.2±21.7 vs. 56.5±20.7; p&lt;0.001; mean APACHE II: 19.8±10.0 vs. 25.1±10.0; p&lt;0.001). Moreover, these patients were at higher risk of meaningful events during hospitalization (e.g. acute kidney injury: 38.0 vs. 66.1%; p&lt;0.001; shock at any time: 52.4 vs. 67.8%; p=0.036). Furthermore, patients with HF had a trend towards higher mortality rates in ICU (17.3 vs. 28.8%; p=0.051) and a significantly higher death in overall hospitalization (30.8 vs. 45.8%; p=0.032). ROC curves performed well in predicting the risk of ICU death regardless of HF (SAPS II – AUC 0.78 vs. 0.81; p=0.36; APACHE II – AUC 0.75 vs. 0.78; p=0.37).

Conclusion

Approximately 1 in every 4 patients admitted to the ICU had chronic HF. Traditional risk scoring systems (SAPS II and APACHE II) performed well regardless of HF. While these results are reassuring as far as risk stratification accuracy is concerned, HF patients remained at a higher risk for worse outcomes. Therefore, prognostic tools with a therapeutic clinical applicability are urgently needed to improve the outcome of this population.

Funding Acknowledgement

Type of funding sources: None.

Antipsychotics in first-episode psychosis: Patterns of prescription in an inpatient unit

Introduction

The treatment of first-episode psychosis patients is different from those with multiple-episode schizophrenia: the response to antipsychotics is better, the required doses are lower and the sensitivity to side-effects is higher. As such, current guidelines recommend a “start slow, go slow” strategy and an active avoidance of side-effects.

Objectives/aims

To know the patterns of antipsychotic prescription in first-episode psychosis patients of our inpatient unit.

Methods

We retrospectively reviewed the clinical data of all non-affective first-episode psychosis patients admitted to the Inpatient Unit C of Hospital de Magalhães Lemos during 2015. The antipsychotics prescribed at admission and discharge were recorded, as well as the doses.

Results

A total of 29 patients were identified. The mean age was 36.6 and 65.5% were man. At admission, all patients were medicated with second-generation antipsychotics: 62.1% with risperidone, 27.6% with olanzapine, 6.9% with paliperidone and 3.4% with aripiprazol. The mean dose of risperidone was 3.5 mg/day. By the time of discharge, 34.5% of patients were prescribed a depot antipsychotic, half of them risperidone. Among those with oral medication only, 55.5% were prescribed risperidone, 22.2% paliperidone and the remainder 22.3% other antipsychotics (aripiprazol, olanzapine or quetiapine). The mean dose of risperidone was 3.7 mg/day.

Conclusions

Second-generation antipsychotics are clearly preferred. The mean dose by the time of discharge is similar to that used in clinical trials. However, antipsychotics are initiated at doses above the minimum effective dose. On discharge, an important proportion of patients are prescribed depot antipsychotics, which are known to improve medication adherence.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Demonstration of Einstein-Podolsky-Rosen Steering Using Single-Photon Path Entanglement and Displacement-Based Detection

We demonstrate the violation of an Einstein-Podolsky-Rosen steering inequality developed for single-photon path entanglement with displacement-based detection. We use a high-rate source of heralded single-photon path-entangled states, combined with high-efficiency superconducting-based detectors, in a scheme that is free of any postselection and thus immune to the detection loophole. This result conclusively demonstrates single-photon entanglement in a one-sided device-independent scenario, and opens the way towards implementations of device-independent quantum technologies within the paradigm of path entanglement.

Isolated Psychiatric Presentation of Anti N-Methyl-D-Aspartate Receptor Encephalitis: A Case Report

Introduction

Anti N-Methyl-D-Aspartate receptor (NMDAR) encephalitis is an autoimmune disorder with a presentation that includes acute behavioral changes, psychosis, cognitive impairment and autonomic instability. In some cases, there are isolated psychiatric symptoms without neurological involvement.

Aims

To raise awareness of the disorder among psychiatrists, considering it a differential diagnosis in a first psychotic episode since a prompt diagnosis and treatment can dramatically affect the outcome.

Objectives

To summarize the latest literature about this field and to present a case report.

Methods

A brief review of the latest literature was performed on PubMed using the keywords “anti N-methyl-D-aspartate receptor encephalitis”, “anti-NMDA encephalitis”, “psychiatric symptoms”.

Results

A 20-year-old male was admitted to our inpatient unit with bizarre delusions of grandious and religious content, somatic hallucinations, sleep cycle inversion and strange behaviour. These symptoms had been present for 1 week and remitted after 10 days of treatment with risperidone. On follow-up, he developed anhedonia, apathy and blunt affect. Brain MRI showed multiple hyperintense changes in T2 and T2-FLAIR, highly suggestive of demyelinating lesions. The cerebrospinal fluid showed mild lymphocytic pleocytosis, mildly increased proteins, oligoclonal bands and anti-NMDAR antibodies of intrathecal production. He was treated with corticoids and the antipsychotic was discontinued. No neurologic symptoms were ever present.

Conclusion

This is an atypical case of anti-NMDAR encephalitis because of its isolated psychiatric presentation. Most patients develop neurological symptoms 2 to 3 weeks after onset of psychiatric symptoms. Monosymptomatic syndromes arise in less than 5% of patients.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Revealing genuine optical-path entanglement

How can one detect entanglement between multiple optical paths sharing a single photon? We address this question by proposing a scalable protocol, which only uses local measurements where single photon detection is combined with small displacement operations. The resulting entanglement witness does not require postselection, nor assumptions about the photon number in each path. Furthermore, it guarantees that entanglement lies in a subspace with at most one photon per optical path and reveals genuinely multipartite entanglement. We demonstrate its scalability and resistance to loss by performing various experiments with two and three optical paths. We anticipate applications of our results for quantum network certification.

Narrowband photon pair source for quantum networks

We demonstrate a compact photon pair source based on a periodically poled lithium niobate nonlinear crystal in a short cavity. This approach provides efficient, low-loss, mode selection that is compatible with standard telecommunication networks. Photons with a coherence time of 8.6 ns (116 MHz) are produced and their purity is demonstrated. A source brightness of 134 pairs (s. mW. MHz)(-1) is reported. The cavity parameters are chosen such that the photon pair modes emitted can be matched to telecom ultra dense wavelength division multiplexing (U-DWDM) channel spacings. The high level of purity and compatibility with standard telecom networks is of great importance for complex quantum communication networks.

Pre- and posttransplant monitoring of alloantibodies by complement-dependent cytotoxicity and luminex methodologies in liver transplantation

BACKGROUND

This study evaluated the influence of circulating anti-HLA antibodies on outcomes of 97 liver allografts from deceased donors.

METHODS

Human leukocyte antigen (HLA) antibody screening was performed by both complement-dependent cytotoxicity (CDC) and multiparameter Luminex microsphere-based assays (Luminex assay).

RESULTS

The agreements between T- and B- cell CDC and Luminex assays were 67% and 77% for pre- and posttransplant specimens, respectively. Graft dysfunction was not associated with either positive pretransplant CDC or Luminex panel-reactive antibody (PRA) values. Likewise, positive posttransplant T- or B- cell CDC PRA values were not associated with graft dysfunction. In contrast, posttransplant Luminex PRA values were significantly higher among patients with graft dysfunction compared with subjects with good outcomes (P = .017).

CONCLUSION

Posttransplant monitoring of HLA antibodies with Luminex methodology allowed identification of patients at high-risk for poor graft outcomes.

Localization and Molecular Characterization of human Breast Cancer Initiating Cells from heterogeneous population of Breast Cancer Mesenchymal Stem cells by mmunofluorescence Microscopy

Breast Cancer (BC) is a heterogeneous disease and arises from breast cancer initiating stem cell population in the tumor and these cells are resistant to cancer therapies. Thus identifying this cell type within the tumor clone is an important area of research to understand the mechanism of breast cancer development. Recently, our laboratory has isolated and characterized Human breast cancer mesenchymal stem cells (hBCMSCs) from human breast cancer and showed the heterogeneity of these cells existing in the tumor. Therefore, our present objective is to use this model system to identify, localize and define specific breast cancer initiating cells (BCICs) from the heterogeneous population of hBCMSCs cell line developed in our laboratory. Localization of specific cell types can be done by using specific cancer marker antibodies using Immunofluorescence microscopy. In this study we have used FITC labeled specific cancer antibodies i.e. p53, Rb1, Hras, Ki67, EGFR, GST, ETS1 and ATF2 to localize BCICs in this population of cells. Our results have demonstrated that few cells among many of the BC cells gave fluorescence with specific cancer antibody indicating that these cell types are BCICs that may be responsible for supporting the growth of other cell type to form tumors. The Phase Contrast Microscopy clearly showed giant cells with enlarged nucleus and scanty cytoplasm associated with many cytoplasmic granules. It also indicates that these cells are mainly responsible for supporting proliferation of surrounding cells that form a part of the BC tumor. We have further hypothesized that molecular profiling of these tumor cells will open a new avenue of molecular targeted therapies for Breast Cancer patients even at an advanced stage of disease.

Assessment of serum L-fucose in brain tumor cases

BACKGROUND

Glycosylation of altered tumor cell in relation to cellular heterogeneity in human intracranial tumors remains relatively unexposed. Serum protein-bound carbohydrate, L-Fucose is reported to be overexpressed during tumor progression by many investigators. Therefore, there is a need to determine the diagnostic, prognostic, functional significance of glycoprotein elevations in various cases of tumors.

OBJECTIVE

The objective of the present study was to evaluate the clinical utility of serum L-fucose in patients with brain tumor.

MATERIALS AND METHODS

Serum glyco-conjugate levels were estimated in 99 patients with brain tumors. Estimation of L-fucose was carried out colorimetrically by the method of Winzler using cysteine hydrochloride.

RESULTS

There was a significant increase in L-fucose level in most of the patients. In the posttreatment cases, the L-fucose levels were apparently low compared to preoperative values.

CONCLUSION

Our results showed that the rise in serum L-fucose may be used as a general marker for brain tumors in addition to other markers.

Assessment of total sialic acid and lipid-bound sialic acid in management of brain tumors

BACKGROUND

Glycoconjugate molecules expressed at the plasma membrane of mammalian cells have been reported to be associated with tumor progression. The measurement of total sialic acid (TSA) and lipid-bound sialic acid (LBSA) in the cerebrospinal fluid (CSF) is suggested to be useful for the diagnosis of brain tumors. But there are very few reports available on the serum glycoconjugate levels in patients with brain tumors.

OBJECTIVE

The objective of this study is to check the feasibility of using serum glycoconjugates such as TSA and LBSA as tumor markers in brain tumor patients.

MATERIALS AND METHODS

Colorimetric estimation of TSA using diphenylamine was done on 100 patients with intracranial tumors; follow-up study was carried out in 24 cases. The LBSA fraction was isolated from the serum of 68 brain tumor patients and evaluated using phosphotungstic acid and resorcinol; follow-up study was done on 23 patients. The various types of brain tumors included in this study were glioma, meningioma, and acoustic neurinoma as well as some other types such as medulloblastoma, secondary tumors, and craniopharyngioma.

RESULTS

There was no significant difference between the TSA and LBSA concentrations seen in pretreatment or post-treatment cases and that seen in control subjects.

DISCUSSION

TSA and LBSA do not have the ability to discriminate between benign and malignant brain tumors. TSA and LBSA appear to be tumor markers of very limited value in patients with brain tumors.

Effect of bentonite characteristics on the elemental composition of wine

Physical, chemical, and mineralogical characteristics of six bentonites were assessed and related to their elemental release to wine. Extraction essays of bentonites in wine at three pH levels were carried out. The multielemental analysis of bentonites and wines was performed by atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). Bentonite addition resulted in significantly higher concentrations of Li, Be, Na, Mg, Al, Ca, Sc, V, Mn, Fe, Co, Ni, Ga, Ge, As, Sr, Y, Zr, Nb, Mo, Cd, Sn, Sb, Ba, W, Tl, Bi, and W. In contrast, the concentrations of B, K, Cu, Zn, and Rb significantly decreased. A strong correlation between Na concentrations of treated wines and its content in bentonite exchange complex was observed. Al and Fe contents reflected bentonite extractable aluminous and ferruginous constituents, while Be, Mg, Ca, V, Mn, Ni, Ge, Zr, Nb, Mo, Sn, Sb, Tl, Pb, and U concentrations reflected the elemental composition of bentonites. Several nonconformances with OIV specifications demonstrated the need for an effective control.

[Surgery of pulmonary metastasis]

Between April 1993 and December 2007, 92 patients underwent the complete resection of pulmonary metastases, 47 mens (51.1%) and 45 womens (49.9%). 26 patients (27.2%) had solitary pulmonary metastasis, 25 (26.1%) multiple pulmonary metastasis and 41 (44.5%) patients presented bilateral pulmonary metastasis. 42 patients (45.6%) presented pulmonary metastasis recurrence, 14 patients (15.2%) a second recurrence and 6 patients (6.5%) a third pulmonary metastasis recurrence. 49 patients (53.2%) were reoperated. The mean cumulative survival after complete resection was 78.4 months (+/- 52.5 months). There were no operative mortality.

CONCLUSION

Thys work demonstrated that every attempt should be made to completely ressect all clinically detected metastases. Complete resection of pulmonary metastasis, even in recurrent disease is compatible with long-term survival.

Weak D type 2 is the most prevalent weak D type in Portugal

The weak D phenotype is the most common D variant, with a frequency of 0.2-1% in Caucasian individuals. There are several weak D types, with different frequencies in European countries, which may pose serologic problems and have the potential for alloimmunization. Samples from Portuguese individuals were tested for RhD by two or three distinct monoclonal and oligoclonal antisera, in direct agglutination tests. When discrepant results were observed, samples were tested with panels of monoclonal anti-D by LISS-indirect antiglobulin test. Cases that reacted weakly with IgM but positive with IgG anti-D were analysed by PCR-sequence-specific primers and real-time PCR. Ninety-nine samples were referred after being characterized as weak D. This genotype was recognized, with a preponderance of weak D type 2 (63.6%) over type 1 (16.2%) and 3 (14.1%). The high incidence of weak D type 2 in our population is in marked contrast to studies performed in other European populations and might be due to our sample selection criteria or ethnic variation. There are advantages in genotyping serologically depressed D samples to avoid the waste of D-negative RBC units and the use of immunoglobulin in pregnant women, who have no risk of alloimmunization.

Micro-geographical variation among male populations of the sandfly, Lutzomyia (Nyssomyia) intermedia, from an endemic area of American cutaneous leishmaniasis in the state of Rio de Janeiro, Brazil

The genetic relationships among male Lutzomyia (Nyssomyia) intermedia (Lutz & Neiva) (Diptera: Psychodidae) from three populations from the same endemic area of American cutaneous leishmaniasis (ACL) in the state of Rio de Janeiro, Brazil, were compared. The sandflies were collected in three ecologically different habitats: domestic, extra-domestic and sylvatic over a total range of 800 m. Three molecular markers were employed to assess population variation. Based on MLEE markers, it could not be concluded that the three populations do not belong to the same gene pool (F(st) = 0.005). No within-population departure from Hardy-Weinberg equilibrium was detected (P < 0.05) and they presented the same level of gene variation. The number of migrants (Nm) indicated that at least 50 individuals per generation migrated between the three habitats. RAPD-PCR markers revealed that, except for the primer five, all were polymorphic. Phenetic analysis of the genotypes showed the presence of two principal clusters corresponding to: (1) domestic plus extra-domestic and (2) sylvatic. Unique genotypes were observed in each population. The sylvatic population was the most polymorphic, showing the largest number of genotypes and low level of similarity between them. Three mtDNA gene markers were studied by SSCP analysis. The most frequent haplotype for each marker ranged in frequency from 60 to 87% and individuals with unique haplotypes varied from 1 to 5%. Interestingly, the SSCP analysis showed a low level of polymorphism within populations. The disagreement between the different molecular markers observed and the hypothesis that L. intermedia could be participating in the transmission cycle of Leishmania (Viannia) braziliensis in environments ranging from the interior of human dwellings to the forest, are discussed.

Polydnavirus replication: the EP1 segment of the parasitoid wasp Cotesia congregata is amplified within a larger precursor molecule

Polydnaviruses are unique viruses: they are essential for successful parasitism by tens of thousands of species of parasitoid wasps. These viruses are obligatorily associated with the wasps and are injected into the host during oviposition. Molecular analyses have shown that each virus sequence in the segmented polydnavirus genome is present in the wasp DNA in two forms: a circular form found in the virus particles and an integrated form found in the wasp chromosomes. Recent studies performed on polydnaviruses from braconid wasps suggested that the circular forms were excised from the chromosome. The different forms of the EP1 circle of Cotesia congregata polydnavirus during the pupal-adult development of the parasitoid wasp were analysed. Unexpectedly, an off-size fragment formerly used to diagnose the integration of the EP1 sequence into wasp genomic DNA was found to be amplified in female wasps undergoing virus replication. The EP1 sequence is amplified within a larger molecule comprising at least two virus segments. The amplified molecule is different from the EP1 chromosomally integrated form and is not encapsidated into virus particles. These findings shed light on a new step towards EP1 circle production: the amplification of virus sequences preceding individual circle excision.

Haemodynamic changes during neck pressure and suction in seated and supine positions

We sought to quantify the contribution of cardiac output (Q) and total vascular conductance (TVC) to carotid baroreflex-mediated changes in mean arterial pressure (MAP) in the upright seated and supine positions. Acute changes in carotid sinus transmural pressure were evoked using brief 5 s pulses of neck pressure and neck suction (NP/NS) via a simplified paired neck chamber that was developed to enable beat-to-beat measurements of stroke volume using pulse-doppler ultrasound. Percentage contributions of Q and TVC were achieved by calculating the predicted change in MAP during carotid baroreflex stimulation if only the individual changes in Q or TVC occurred and all other parameters remained at control values. All NP and NS stimuli from +40 to -80 Torr (+5.33 to -10.67 kPa) induced significant changes in Q and TVC in both the upright seated and supine positions (P < 0.001). Cardiopulmonary baroreceptor loading with the supine position appeared to cause a greater reliance on carotid baroreflex-mediated changes in Q. Nevertheless, in both the seated and supine positions the changes in MAP were primarily mediated by alterations in TVC (percentage contribution of TVC at the time-of-peak MAP, seated 95 +/- 13, supine 76 +/- 17 %). These data indicate that alterations in vasomotor activity are the primary means by which the carotid baroreflex regulates blood pressure during acute changes in carotid sinus transmural pressure.

Blood group antigen profile predicted by molecular biology-use of real-time polymerase chain reaction to genotype important KEL, JK,RHD, and RHCE alleles

The most clinically important blood group systems in transfusion medicine, excluding the ABO system, are the RH, Kell, and Kidd systems. Alloantibodies to antigens of these systems may be produced following blood transfusion or during pregnancy and can result in serious hemolytic transfusion reactions and hemolytic disease of the newborn. We developed rapid and robust techniques for RHD, RHCE, KEL, and JK genotyping with the use of a real-time polymerase chain reaction instrument. Two fluorescence-based methods for the detection of amplification products were used: for KEL1/KEL2, JK1/JK2, and RHE/RHe (exon 5) we used the hybridization probes protocol; for RHC/RHc the analysis was done in sequences of exon 1 for RHC and exon 2 for RHc; and for RHD, analysis was done in sequences of intron 4, exon 7, and exon 4 pseudogene using the SYBR Green I protocol. The genotyping tests were validated with samples from 85 Caucasian Portuguese and 15 Black European blood donors. Complete phenotype-genotype correlations were obtained. The potential use of the presented methods can be predicted in clinical transfusion medicine, allowing appropriate monitoring, early intervention, and improved care. When blood group genotyping techniques are necessary, this methodology is highly competitive for a routine laboratory.

Rapid genotyping of the major alleles at the Duffy (FY) blood group locus using real-time fluorescence polymerase chain reaction

The Duffy blood group system has clinical importance due to involvement in transfusion reactions and hemolytic disease of the newborn. Recently, the molecular basis of the two alleles, FY*A and FY*B (125G>A), and the mutation situated in the promoter region of the FY gene (-33T>C), have been elucidated. In order to develop an accurate, easy, and rapid genotyping method, we describe a procedure using the LightCycler. Samples from 53 Caucasian Portuguese blood donors and 7 black, healthy, European individuals were phenotyped with commercial antisera. DNA was extracted from blood samples and the relevant sequences were amplified with the same cycling conditions, using real-time polymerase chain reaction. The melting point of the FY*A allele was 63 degrees C and of the FY*B allele, 55 degrees C. The allele without mutation at the promoter region had a melting point at 64 degrees C and the FY*B silent allele at 58 degrees C. The results in Caucasian individuals were similar to those found in European and American populations. When FY genotyping techniques are necessary, the methodology described is preferable to conventional methods as it is reliable, high speed, and uses small volumes, providing a highly competitive technology for use by a routine laboratory.

Genetic risk factors in acute coronary disease

OBJECTIVE

We investigate whether each of the following: HPA-1, Factor V Leiden, prothrombin gene variant and the methylene tetrahydrofolate reductase gene (MTHFR) mutation, are risk factors for acute coronary disease in Portuguese patients.

MATERIAL AND METHODS

100 blood donors and 52 patients with an established diagnosis of myocardial infarction or unstable angina were evaluated for genetic risk factors, by determining HPA-1 genotype, Factor V Leiden, Prothrombin 20210 variant and MTHFR mutation.

RESULTS

We found a prevalence of 2.0% for Factor V Leiden, 5.0% for the Prothrombin 20210 variant and 66% for the MTHFR mutation in blood donors. These values are similar to those found in the patients (1.9, 3.8 and 58%, respectively). We found that 28/100 controls had the PI(A2) polymorphism, a frequency statistically different from that in the patients (23/52). This difference was even more pronounced in patients less than 60 years old (27/96 vs. 13/24).

CONCLUSION

Factor V Leiden, Prothrombin 20210 variant and MTHFR mutation do not seem to represent risk factors for acute coronary disease. However, the PI(A2) polymorphism could have a role in the pathogenesis of this disease. The presence of multiple genetic factors, more than single ones, could influence the development and outcome of myocardial infarction and unstable angina. Larger studies are needed in order to have a better insight into the pathophysiological mechanisms of this disease, along with its prevention and the development of new treatments.

[Parvovirus B19 infection]

In 1975, during blood screening for hepatitis B, Cossart et al. discovered the human parvovirus B19 (B19). It is a small, single strand DNA virus of the Parvoviridae family. This virus is widespread with 40-80% of adults showing evidence of infection. It is found in the respiratory secretions of viraemic patients and direct contact has been suggested as the most likely mode of transmission. Parenteral transmission is common during treatment with clotting-factor concentrates, but rarely occurs during transfusion with single donor products. Although B19 usually causes a self-limited illness, complications of infection can be severe and at times life threatening. In pregnant women, infection can lead to spontaneous abortions and hydrops fetalis and, in patients with haemolytic anaemias or in immunocompromised individuals, can induce aplastic crisis and chronic anaemias. The diagnosis can be made by indirect (testing for B19 antibodies) or direct methods (detecting B19 viremia). There are no vaccines or specific therapy currently available. Contact isolation is recommended for hospitalized patients.

The blood bank and hepatitis G

HGV can be transmitted by transfusion and is capable of inducing persistent infection. Thus far it appears to have no discernable disease association. We determined the infection rate of HGV in volunteer blood donors and patient with risk factors for viral transmission through the blood. The association between HGV infection and exposure to labile blood products could be a problem for blood banks in the future.

Identification of patients at high risk of graft loss by pre- and posttransplant monitoring of anti-HLA class I IgG antibodies by enzyme-linked immunosorbent assay

Identification of risk factors influencing graft survival may lead to the development of models to predict graft outcome. Such models may provide guidance for immunosuppressive therapy, measure posttransplantation outcome, and eventually improve graft survival in high-risk patients. A major risk factor influencing graft survival is allosensitization. However, due to the lack of standardization of lymphocytotoxicity assays, the detection of alloantibodies utilizing this current methodology may not correlate with posttransplant events. Recently, a novel standardized enzyme-linked immunosorbent assay (ELISA) for the detection of anti-HLA class I IgG antibodies was developed. To evaluate the predictive value of this diagnostic test, a retrospective analysis of 124 renal allograft recipients with an 18-month follow-up time was performed. A highly significant (P=0.01) correlation between pre-transplant ELISA panel reactive antibody (PRA) results and graft loss was observed. Patients with pre-transplant ELISA PRA of >10% had a three times higher risk of graft loss compared with patients who tested negative. No such correlation was observed with complement-dependent cytotoxicity results independent of the reduction of IgM antibodies with dithiothreitol. Similarly, a highly significant correlation of ELISA results with the occurrence of early graft dysfunction was observed. Almost all patients (88%) with a pretransplant ELISA PRA of >50% required posttransplant dialysis, compared with 45% of patients with a pretransplant ELISA PRA of 10-50% and 27% of patients with a pretransplant ELISA PRA of <10%. No such difference was observed with complement-dependent cytotoxicity %PRA values. Analysis of posttransplant specimens by ELISA demonstrated a strong correlation of assay results with graft rejection and graft dysfunction. In summary, these results suggest that detection of anti-HLA class I antibodies by ELISA identifies patients at high risk for graft loss. No other single risk factor of such magnitude has been identified so far.

Pretransplant rejection risk assessment through enzyme-linked immunosorbent assay analysis of anti-HLA class I antibodies

Soluble HLA enzyme-linked immunosorbent assays (ELISAs) for the detection of anti-HLA class I immunoglobulin G (IgG), IgG1, IgG2, IgG3, IgG4, IgM, and IgA antibodies were developed and used to analyze retrospectively the correlation between pretransplant allosensitization and posttransplant rejection episodes in renal allograft recipients. Enzyme-linked immunosorbent assay plates were coated with 46 different soluble HLA preparations representing 40 different HLA class I antigens. After incubation with a serum specimen, bound antibodies were detected with a peroxidase-conjugated antibody. Serum specimens from 85 patients were analyzed. All patients tested positive by microlymphocytotoxicity (ie, >5% panel-reactive antibody [PRA]). Approximately half (56%) of the patients had experienced one or more rejection episodes within 12 months posttransplantation. Fifty-five patients tested positive by ELISA (total IgG %PRA >10%). A strong correlation between first-year rejection and ELISA-detected anti-HLA class I IgG1 was observed (P = 0.0004). The predictive value for IgG1 and first-year rejection was 77.5%, demonstrating that ELISA results identify patients at high risk of rejecting the transplanted kidney. Anti-HLA class I total IgG detected by ELISA also correlated with first-year rejection episodes (P = 0.04). The presence of anti-HLA class I IgG2, IgG3, IgG4, or IgM was not predictive of first-year rejection episodes. Anticlass I IgA antibodies were only found in combination with anti-class I IgG1 antibodies.

Soluble HLA antigens and ELISA--a new technology for crossmatch testing

A soluble HLA ELISA for the detection of donor specific anti-HLA class I IgG antibodies was developed and compared with microlymphocytotoxicity. Donor sHLA was prepared from donor blood or purified blood lymphocytes and captured onto monoclonal antibody coated ELISA plates. After incubation of captured HLA with test serum, bound IgG antibodies were detected using a peroxidase-conjugated anti-human IgG antibody. Serum samples from patients on waiting lists to receive kidney transplants were tested by lymphocytotoxicity (AHG protocol) and/or sHLA ELISA in four different laboratories using HLA preparations from eight organ donors. Concordant crossmatch results were obtained for 854 (99%) of 864 ELISA crossmatches. In contrast, concordant results were obtained for 234 (91%) of 256 lymphocytotoxicity crossmatches. Interlaboratory reproducibility of ELISA results was 99%. In contrast, interlaboratory reproducibility of lymphocytotoxicity assay results was 78%. Endpoint titrations of serum specimens containing anti-HLA antibodies demonstrated equivalent sensitivity of ELISA and AHG lymphocytotoxicity crossmatch and similar sensitivity of ELISA and flow cytometry crossmatch. Specimens tested positive by lymphocytotoxicity without DTT treatment but negative with DTT treatment were tested negative by ELISA. Comparison of lymphocytotoxicity and ELISA crossmatch results showed an agreement of 94%. This demonstrates that detection of anti-donor HLA class I antibodies by ELISA is a reliable alternative to microlymphocytotoxicity testing.

Soluble HLA antigens and ELISA--a new technology for crossmatch testing

A soluble HLA ELISA for the detection of donor specific anti-HLA class I IgG antibodies was developed and compared with microlymphocytotoxicity. Donor sHLA was prepared from donor blood or purified blood lymphocytes and captured onto monoclonal antibody coated ELISA plates. After incubation of captured HLA with test serum, bound IgG antibodies were detected using a peroxidase-conjugated anti-human IgG antibody. Serum samples from patients on waiting lists to receive kidney transplants were tested by lymphocytotoxicity (AHG protocol) and/or sHLA ELISA in four different laboratories using HLA preparations from eight organ donors. Concordant crossmatch results were obtained for 854 (99%) of 864 ELISA crossmatches. In contrast, concordant results were obtained for 234 (91%) of 256 lymphocytotoxicity crossmatches. Interlaboratory reproducibility of ELISA results was 99%. In contrast, interlaboratory reproducibility of lymphocytotoxicity assay results was 78%. Endpoint titrations of serum specimens containing anti-HLA antibodies demonstrated equivalent sensitivity of ELISA and AHG lymphocytotoxicity crossmatch and similar sensitivity of ELISA and flow cytometry crossmatch. Specimens tested positive by lymphocytotoxicity without DTT treatment but negative with DTT treatment were tested negative by ELISA. Comparison of lymphocytotoxicity and ELISA crossmatch results showed an agreement of 94%. This demonstrates that detection of anti-donor HLA class I antibodies by ELISA is a reliable alternative to microlymphocytotoxicity testing.