Day or overnight transfusion in critically ill patients: does it matter?

BACKGROUND AND OBJECTIVES: The timing of blood administration in critically ill patients is first driven by patients' needs. This study aimed to define the epidemiology and significance of overnight transfusion in critically ill patients. MATERIALS AND METHODS: This is a post hoc analysis of a prospective multicentre observational study including 874 critically ill patients receiving red blood cells, platelets, fresh frozen plasma (FFP) or cryoprecipitate. Characteristics of patients receiving blood only during the day (8 am up until 8 pm) were compared to those receiving blood only overnight (8 pm up until 8 am). Characteristics of transfusion were compared, and factors independently associated with major bleeding were analysed. RESULTS: The 287 patients transfused during the day only had similar severity and mortality to the 258 receiving blood products overnight only. Although bleeding-related admission diagnoses were similar, major bleeding was the indication for transfusion in 12% of patients transfused in daytime only versus 30% of patients transfused at night only (P < 0·001). Similar total amount of blood products were transfused at day and night (2856 versus 2927); however, patients were more likely to receive FFP and cryoprecipitate at night compared with daytime. Overnight transfusion was independently associated with increased odds of major bleeding (odds ratio, 3·16, 95% confidence interval, 2·00-5·01). CONCLUSION: Transfusion occurs evenly across day and night in ICU; nonetheless, there are differences in type of blood products administered that reflect differences in indication. Critically ill patients were more likely to receive blood for major bleeding at night irrespective of admission diagnosis.

Diagnosis and management of thrombotic thrombocytopenic purpura (TTP) in Australia: findings from the first 5 years of the Australian TTP/thrombotic microangiopathy registry.

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening thrombotic microangiopathy (TMA). In 2009, the Australian TTP/TMA registry was established to collect data on patients presenting with TTP/TMA throughout Australia. AIM: To summarise information on the diagnosis and management of patients with TTP collected in the first 5 years (2009-2014) of the Australian TTP registry. METHODS: Registry data from June 2009 to October 2014 were reviewed. RESULTS: Fifty-seven patients were identified with TTP (defined as ADAMTS13 activity <10%), accounting for 72 clinical episodes. ADAMTS13 inhibitor testing was performed in nine out of 57 patients (16%), reflecting the limited availability of accredited testing facilities. Sixty-seven out of 72 episodes were treated with therapeutic plasma exchange (PEx) using cryodepleted plasma (40% of episodes), fresh frozen plasma (36%) or a mixture (22%). Median exposure to plasma products was 55.9 L. PEx was commenced ≥2 days from stated diagnosis in 15% of episodes. Adverse reactions to PEx were common with documented allergic reactions (including life threatening) in 21% of episodes. Adjunctive immunosuppression was documented in 76% of episodes (corticosteroid 71% and rituximab 39%). Platelet transfusion was administered in 15% of episodes. CONCLUSIONS: Data from the Australian TTP/TMA registry suggest a heterogenous approach to the diagnosis and management of TTP in Australia over the assessed period. These observations highlight areas for improvement and standardisation of practice, including comprehensive diagnostic testing, more immediate access to PEx and a more uniform approach to adjunctive immunosuppression and supportive care.

Electrically excited inverse electron spin resonance in a split-ring metamaterial resonator.

Bianisotropic properties of the metamaterial built from split-ring resonators are utilized to excite electron-spin resonance in a gadolinium gallium garnet by the electric field of light. Surprisingly, the observed electron-spin resonance signal is seen as a maximum in the field-dependent transmittance, which indicates strong modifications of the metamaterial parameters in the coupled regime. In the geometry where both modes, electron-spin resonance and split-ring resonance, are active, the anticrossing regime can be observed. These effects can be explained using the classical model of two coupled oscillators and the bianisotropic properties of split-ring resonators.

Emergence and diversity of different HIV-1 subtypes in South Africa, 2000-2001.

HIV-1 is a major health problem in South Africa with an average prevalence rate of 29.1% in pregnant women and between 4.9 and 6.1 million people infected. Using env gp120 V3 serotyping and genotyping techniques 410 patient samples were investigated. Most of the samples were obtained from different clinics in the greater Cape Town area of the Western Cape Province in South Africa. These included an academic hospital, state and private clinics, an informal settlement, sex worker cohorts, and the blood transfusion services. RNA was extracted from plasma samples followed by RT-PCR and sequencing of the env gp120 V3 region. Sequence fragments were assembled using Sequencher V4.7 and subsequently codon aligned. Distance calculation, tree construction methods, and bootstrap analysis were implemented using MEGA version 4.0. Viral load measurements indicated that HIV-1 RNA levels from 74 samples were below the assay detection limit. Three hundred thirty-six samples were used for env PCR and sequencing and 320 were assigned to subtypes. The majority of the sequences were subtyped as C (n = 285, 89.0%). Other subtypes detected were subtype A (n = 10, 3.1%); subtype B (n = 22, 6.8%); one each of subtypes F1, G, U, and a CH recombinant. Whether this diversity will have major implications for HIV-1 evolution and vaccine development in this region remains undetermined.

Zidovudine with nevirapine for the prevention of HIV mother-to-child transmission reduces nevirapine resistance in mothers from the Western Cape, South Africa.

In the Western Cape province of South Africa, an intensified regimen for the prevention-of-mother-to-child-transmission-of-HIV consisting of zidovudine (AZT) from 34 weeks of pregnancy plus single dose (sd) nevirapine (NVP) during labor was instituted in 2004. The newborn baby receives a single dose of NVP and AZT for 7 days. Similar strategies in Thailand and Africa have been shown to be more effective in reducing transmission than NVP alone. The use of sd NVP only for the prevention-of-mother-to-child-transmission-of-HIV has a high risk of inducing resistance (25-69%) with an average of 35.7% by a recent meta-analysis and has been shown to adversely affect non-nucleoside reverse transcriptase inhibitor (NNRTI)-based antiretroviral therapy when initiated within 6 months. In this study the prevalence of resistance to NVP and AZT in mothers who had received the intensified regimen was measured. Specimens collected from mothers were genotyped by in-house PCR and sequencing. In specimens obtained within 60 days of delivery, acquired NVP resistance mutations were detected in 13 of 76 patients (17.1%, 95% confidence interval: 8.7-25.6%), which appears to be lower than in studies with sd NVP alone (37.5%, 95% confidence interval: 23.0-50.6%).

Comparison of 68Ga-DOTATOC PET and 111In-DTPAOC (Octreoscan) SPECT in patients with neuroendocrine tumours.

PURPOSE: Neuroendocrine tumours (NETs) can be imaged with scintigraphy using radiolabelled somatostatin analogues. The aim of our study was to compare the value of (68)Ga-DOTATOC PET and (111)In-DTPAOC SPECT (Octreoscan) in the detection of NET manifestations. METHODS: Twenty-seven NET patients were prospectively examined. (68)Ga-DOTATOC PET and (111)In-DTPAOC SPECT were performed using standard techniques. Treatment was not applied in between. Mean and maximum standardised uptake values (SUVs) were calculated for PET findings. Tumour/non-tumour ratios were calculated for SPECT findings. Findings were compared by a region-by-region analysis and verified with histopathology, CT and MRI within 21 days. RESULTS: SUVs of positive lesions on (68)Ga-DOTATOC PET ranged from 0.7 to 29.3 (mean SUV) and from 0.9 to 34.4 (maximum SUV). Tumour/non-tumour ratios on (111)In-DTPAOC SPECT ranged from 1.8 to 7.3. In imaging lung and skeletal manifestations, (68)Ga-DOTATOC PET was more efficient than (111)In-DTPAOC SPECT. All discrepant lung findings and 77.8% of discrepant osseous findings were verified as true positive PET interpretations. In regional comparison of liver and brain, (68)Ga-DOTATOC PET and (111)In-DTPAOC SPECT were identical. In lymph nodes, the pancreas and the gastro-intestinal system, different values of the two techniques were not indicated in regional analyses. In a single patient, surgical interventions were changed on the basis of (68)Ga-DOTATOC PET findings. CONCLUSION: (68)Ga-DOTATOC PET is superior to (111)In-DTPAOC SPECT in the detection of NET manifestations in the lung and skeleton and similar for the detection of NET manifestations in the liver and brain. (68)Ga-DOTATOC PET is advantageous in guiding the clinical management.

Serotyping and genotyping of HIV-1 infection in residents of Khayelitsha, Cape Town, South Africa.

It is estimated that between 5.5 and 6.1 million people are infected with HIV/acquired immunodeficiency syndrome (AIDS) in South Africa, with subtype C responsible for the majority of these infections. The Khayelitsha suburb of Cape Town has one of the highest HIV prevalence rates in South Africa. Overcrowding combined with unemployment and crime in parts of the area perpetuates high-risk sexual behavior, which increases exposure to infection by HIV. Against this background, the objective of this study was to characterize HIV-1 in residents confirmed to be seropositive. Serotyping was performed through a competitive enzyme-linked immunosorbent assay (cPEIA). Genotyping methods included RNA isolation followed by RT-PCR and sequencing of the gag p24, env gp41 immunodominant region (IDR), and env gp120 V3 genome regions of HIV-1. With the exception of a possible C/D recombinant strain, all HIV-1 strains were characterized as HIV-1 group M subtype C. One individual was shown to harbor multiple strains of HIV-1 subtype C. In Southern Africa, the focus has been to develop a subtype C candidate vaccine, as this is the major subtype found in this geographical area. Therefore, the spread of HIV-1 and its recombinant strains needs to be monitored closely.

Microbial content of commercial South African high-moisture dried fruits.

AIM: The aim was to evaluate commercially available South African high-moisture dried fruits (HMDF) for the microbial, moisture and SO2 contents, as well as aw and pH. METHODS AND RESULTS: The microbial content of commercially available HMDF was evaluated using nine different growth media. The moisture content, aw) SO2 and pH of each product were determined using standard analytical methods. It was found that the highest total aerobic counts were generated from high-moisture dried (HMD) prunes and raisins. The most frequent spoilers were members of the genus Bacillus. Fungal counts were also very high in the apricot products, exceeding the limit of 1000 CFU g(-1) as set by HMDF producers. Members of the genus Staphylococcus were found in the HMD raisins and Salmonella and thermoduric organisms were isolated from the HMD prunes. CONCLUSIONS: The microbial levels of South African HMDF were within the limits set, with the exception of apricots. SIGNIFICANCE AND IMPACT OF STUDY: The study shows the presence of Salmonella, Staphylococcus and Clostridium in South African HMDF. The presence of thermoduric organisms indicated that the current pasteurization process is not adequate and that the addition of preservatives would be an additional method to ensure safety and quality.

Molecular characteristics of human immunodeficiency virus type 1 subtype C viruses from KwaZulu-Natal, South Africa: implications for vaccine and antiretroviral control strategies.

The KwaZulu-Natal region of South Africa is experiencing an explosive outbreak of human immunodeficiency virus type 1 (HIV-1) subtype C infections. Understanding the genetic diversity of C viruses and the biological consequences of this diversity is important for the design of effective control strategies. We analyzed the protease gene, the first 935 nucleotides of reverse transcriptase, and the C2V5 envelope region of a representative set of 72 treatment-naïve patients from KwaZulu-Natal and correlated the results with amino acid signature and resistance patterns. Phylogenetic analysis revealed multiple clusters or "lineages" of HIV-1 subtype C that segregated with other C viruses from southern Africa. The same pattern was observed for both black and Indian subgroups and for retrospective specimens collected prior to 1990, indicating that multiple sublineages of HIV-1 C have been present in KwaZulu-Natal since the early stages of the epidemic. With the exception of three nonnucleoside reverse transcriptase inhibitor mutations, no primary resistance mutations were identified. Numerous accessory polymorphisms were present in the protease, but none were located at drug-binding or active sites of the enzyme. One frequent polymorphism, I93L, was located near the protease/reverse transcriptase cleavage site. In the envelope, disruption of the glycosylation motif at the beginning of V3 was associated with the presence of an extra protein kinase C phosphorylation site at codon 11. Many polymorphisms were embedded within cytotoxic T lymphocyte or overlapping cytotoxic T-lymphocyte/T-helper epitopes, as defined for subtype B. This work forms a baseline for future studies aimed at understanding the impact of genetic diversity on vaccine efficacy and on natural susceptibility to antiretroviral drugs.

Genetic analysis of the complete gag and env genes of HIV type 1 subtype C primary isolates from South Africa.

South Africa has one of the fastest growing HIV-1 epidemics, with an estimated 4.7 million people infected. To better understand the genetic diversity of this epidemic and its potential impact on vaccine development, we have cloned and sequenced the complete gag and env genes of 13 primary virus isolates. Phylogenetic analysis of our sequences and 69 complete env genes from the Los Alamos and GenBank databases revealed multiple subclusters within subtype C. The V3 loop region was relatively conserved in all our strains when compared with other subtypes, but the region immediately downstream was highly variable. No intersubtype recombinant forms were observed when comparing the gag and env sequences. Characterization of the complete gag and env genes enabled us to select specific strains for further vaccine development.

FHIT RNA and protein expression in oral squamous cell carcinomas.

BACKGROUND: To investigate the possible role of FHIT, a possible tumour suppressor gene, in oral carcinogenesis, we examined 17 oral squamous cell carcinomas (OSCCs) for genetic alterations. MATERIALS AND METHODS: Fresh tissue was obtained during surgery, snap-frozen in liquid nitrogen and stored at -70 degrees C. Nested PCR amplification to examine the integrity of FHIT mRNA was performed on the reverse transcribed complementary DNA obtained from the frozen normal and tumour tissue. Immunohistochemistry was done on formal in-fixed paraffin-embedded tissue protein from the same cases using a polyclonal antiserum against the full length Fhit. RESULTS: Twelve out 17 (71%) OSCCs showed reduced or absent Fhit protein and half of the cases with reduced Fhit protein exhibited aberrant RT-PCR products. CONCLUSION: Immunohistochemical detection of Fhit protein expression in OSCCs is the more sensitive method to determine the status of Fhit in these tumours, in agreement with previous studies of other tumour types.

Inter-subunit rotation and elastic power transmission in F0F1-ATPase.

ATP synthase (F-ATPase) produces ATP at the expense of ion-motive force or vice versa. It is composed from two motor/generators, the ATPase (F1) and the ion translocator (F0), which both are rotary steppers. They are mechanically coupled by 360 degrees rotary motion of subunits against each other. The rotor, subunits gamma(epsilon)C10-14, moves against the stator, (alphabeta)3delta(ab2). The enzyme copes with symmetry mismatch (C3 versus C10-14) between its two motors, and it operates robustly in chimeric constructs or with drastically modified subunits. We scrutinized whether an elastic power transmission accounts for these properties. We used the curvature of fluorescent actin filaments, attached to the rotating c ring, as a spring balance (flexural rigidity of 8.10(-26) N x m2) to gauge the angular profile of the output torque at F0 during ATP hydrolysis by F1. The large average output torque (56 pN nm) proved the absence of any slip. Angular variations of the torque were small, so that the output free energy of the loaded enzyme decayed almost linearly over the angular reaction coordinate. Considering the three-fold stepping and high activation barrier (>40 kJ/mol) of the driving motor (F1) itself, the rather constant output torque seen by F0 implied a soft elastic power transmission between F1 and F0. It is considered as essential, not only for the robust operation of this ubiquitous enzyme under symmetry mismatch, but also for a high turnover rate under load of the two counteracting and stepping motors/generators.

F-ATPase: forced full rotation of the rotor despite covalent cross-link with the stator.

In ATP synthase (F(O)F(1)-ATPase) ion flow through the membrane-intrinsic portion, F(O), drives the central "rotor", subunits c(10)epsilongamma, relative to the "stator" ab(2)delta(alphabeta)(3). This converts ADP and P(i) into ATP. Vice versa, ATP hydrolysis drives the rotation backwards. Covalent cross-links between rotor and stator subunits have been shown to inhibit these activities. Aiming at the rotary compliance of subunit gamma we introduced disulfide bridges between gamma (rotor) and alpha or beta (stator). We engineered cysteine residues into positions located roughly at the "top," "center," and "bottom" parts of the coiled-coil portion of gamma and suitable residues on alpha or beta. This part of gamma is located at the center of the (alphabeta)(3) domain with its C-terminal part at the top of F(1) and the bottom part close to the F(O) complex. Disulfide bridge formation under oxidizing conditions was quantitative as shown by SDS-polyacrylamide gel electrophoresis and immunoblotting. As expected both the ATPase activities and the yield of rotating subunits gamma dropped to zero when the cross-link was formed at the center (gammaL262C <--> alphaA334C) and bottom (gammaCys(87) <--> betaD380C) positions. But much to our surprise disulfide bridging impaired neither ATP hydrolysis activity nor the full rotation of gamma and the enzyme-generated torque of oxidized F(1), which had been engineered at the top position (gammaA285C <--> alphaP280C). Apparently the high torque of this rotary engine uncoiled the alpha-helix and forced amino acids at the C-terminal portion of gamma into full rotation around their dihedral (Ramachandran) angles. This conclusion was supported by molecular dynamics simulations: If gammaCys(285)-Val(286) are attached covalently to (alphabeta)(3) and gammaAla(1)-Ser(281) is forced to rotate, gammaGly(282)-Ala(284) can serve as cardan shaft.

Planning of reach-and-grasp movements: effects of validity and type of object information.

Individuals are assumed to plan reach-and-grasp movements by using two separate processes. In 1 of the processes, extrinsic (direction, distance) object information is used in planning the movement of the arm that transports the hand to the target location (transport planning); whereas in the other, intrinsic (shape) object information is used in planning the preshaping of the hand and the grasping of the target object (manipulation planning). In 2 experiments, the authors used primes to provide information to participants (N = 5, Experiment 1; N = 6, Experiment 2) about extrinsic and intrinsic object properties. The validity of the prime information was systematically varied. The primes were succeeded by a cue, which always correctly identified the location and shape of the target object. Reaction times were recorded. Four models of transport and manipulation planning were tested. The only model that was consistent with the data was 1 in which arm transport and object manipulation planning were postulated to be independent processes that operate partially in parallel. The authors suggest that the processes involved in motor planning before execution are primarily concerned with the geometric aspects of the upcoming movement but not with the temporal details of its execution.

Viscoelastic dynamics of actin filaments coupled to rotary F-ATPase: angular torque profile of the enzyme.

ATP synthase (F(O)F(1)) operates as two rotary motor/generators coupled by a common shaft. Both portions, F(1) and F(O), are rotary steppers. Their symmetries are mismatched (C(3) versus C(10-14)). We used the curvature of fluorescent actin filaments, attached to the rotating c-ring, as a spring balance (flexural rigidity of 8. 10(-26) Nm(2)) to gauge the angular profile of the output torque at F(O) during ATP hydrolysis by F(1) (see theoretical companion article (. Biophys. J. 81:1234-1244.)). The large average output torque (50 +/- 6 pN. nm) proved the absence of any slip. Variations of the torque were small, and the output free energy of the loaded enzyme decayed almost linearly over the angular reaction coordinate. Considering the threefold stepping and high activation barrier of the driving motor proper, the rather constant output torque implied a soft elastic power transmission between F(1) and F(O). It is considered as essential, not only for the robust operation of this ubiquitous enzyme under symmetry mismatch, but also for a high turnover rate of the two counteracting and stepping motor/generators.

Characterization and phylogenetic analysis of South African HIV-1 subtype C accessory genes.

To acquire new knowledge about the genetic diversity and potential impact on vaccine strategies of HIV-1 subtype C in South Africa, we have characterized the vif, vpr, and vpu genes of 15 isolates. Phylogenetic analysis of the genomic fragment encompassing these genes revealed subtype C subclusters, suggesting close relatedness with subtype C strains from other geographic locations and excluded isolation of South African strains. The putative T155 phosphorylation site in the C terminal of Vif was absent in all subtype C sequences. Variation in the predicted amino acid sequences of the three genes further showed strong correlation with other subtype C sequences.

Epstein-Barr virus strain characterisation in South African patients with nasopharyngeal carcinomas.

UNLABELLED: Epstein-Barr virus (EBV) has been implicated in various diseases, among others, nasopharyngeal carcinoma (NPC). In this study we investigated the frequency and subtype distribution of EBV in 39 NPCs. The presence of EBV was detected by using a nested PCR to amplify the Bam Hl W-fragment of the genome. Two regions were targeted for subtype analysis, namely the EBNA-2A and EBER regions. PCR was used to amplify these regions, and the EBER region was sequenced to detect subtype specificity. The results showed that EBV could be detected in 82% (31/38) of the tumours. In 15 of these, EBNA subtypes could be identified of which 14 were subtype A and one tumour had both subtypes A and B present. The EBER region was amplified in 21 samples. The majority of cases (18/21) demonstrated a mutation profile which consisted of 5 type B and one type A mutations. The consensus type is therefore type B. IN CONCLUSION: a strong association was found between EBV and NPCs in our group of patients and their "consensus" genotype was A/B based on the two genome areas investigated.