Repeat testing for anti-HBc, HBsAg, anti-HBe, and anti-HBs may he

Repeat testing for anti-HBc, HBsAg, anti-HBe, and anti-HBs may help rule out a false-positive result, and vaccination might be in order.[8, 9] The presence of IgM anti-HBc or anti-HBe would Sirolimus molecular weight indicate recent HBV infection or prior exposure to HBV, respectively, and further follow-up to assess serum alanine aminotransferase activity and changes of serological markers may be necessary. Finally, in individuals with persistent isolated anti-HBc, serum HBV DNA to exclude chronic HBV infection and screening for HCV and HIV may also merit consideration.[8, 9] “
“The aim of the study was to assess whether pill burden is associated with self-reported adherence to current

combination antiretroviral regimens and health status in a large sample of unselected and chronically treated HIV-infected patients. An adherence and health status questionnaire was offered to all patients collecting their drugs between March and May 2010 at our clinic; both parameters were primarily evaluated using a visual analogue scale. Linear correlations were evaluated using Spearman’s correlation coefficient. Wilcoxon’s rank-sum test and the χ2 test were used to compare quantitative and qualitative PTC124 cell line variables. The generalized linear model was used in multivariable analyses.

Among 2763 subjects on treatment during the study period, 2114 (78.8% male; mean age 46.9 ± 8.84 years) were tested for adherence; 1803 (85.3%) had viral loads < 50 HIV-1 RNA copies/mL. After adjusting for age, gender, HIV risk factor, current CD4 count, pill burden and dosing interval, adherence was higher in patients with undetectable

HIV RNA (P < 0.0001) and directly associated with current CD4 count (P = 0.029). After adjusting for the same variables, health status was better in patients with undetectable viraemia (P = 0.004) and in men who have sex with men (MSM) and heterosexuals compared with injecting drug users and those with other risk factors (P < 0.0001 for MSM and P = 0.008 for heterosexuals); it was also directly associated with current CD4 count (P < 0.0001) and inversely associated with age (P < 0.0001) and pill burden (P = 0.019). In this highly adherent population, the number of daily pills was related to self-reported Phosphoglycerate kinase health status but not to self-reported adherence, whereas the dosing interval did not influence self-reported adherence or health status. “
“Linkage to care after HIV diagnosis remains underinvestigated in Europe, yet delays in linkage to care are an important obstacle to controlling the HIV epidemic. The Test and Keep in Care (TAK) project aims to determine the prevalence of HIV-positive persons who are lost or late to care and factors associated with this. Data from community-based voluntary counselling and testing that occurred in 2010–2011 were linked with data from HIV clinics using unique test numbers. Persons not registered in HIV clinics were considered lost to care (LTC).

, 2007) There is a pressing need for the identification of novel

, 2007). There is a pressing need for the identification of novel drug targets, virulence factors and development of vaccines to expand our understanding of the prevention and treatment of leishmaniasis. The enzymes of the sterol biosynthesis pathway are attractive targets for the specific treatment of leishmaniasis as the aetiological agents of the disease require endogenous ergosterol and other alkylated sterols for growth and survival (Urbina et al., 2002). The formation of squalene is the first committed step in sterol biosynthesis and a blockade at this level of the pathway learn more does not affect the production of other essential isoprenoids and the accumulated isoprenoid intermediates (farnesyl pyrophosphate

and precursors) can be readily metabolized and excreted (Gonzalez-Pacanowska et al., 1988). For

these reasons, SSN is currently under intense study as a possible target for cholesterol-lowering agents in humans (Bergstrom et al., 1995; Watson & Procopiou, 1996). Significant advances have been made in the understanding of the reaction mechanism of the vertebrate SSN (Mookhtiar et al., 1994) and recently, the crystal structure of a soluble, fully active form of the human enzyme was reported (Pandit et al., 2000). Overexpression or selection studies in Leishmania major (Cotrim et al., 1999) have shown that the expression of SSN is strongly activated in these cells in the presence BLZ945 mouse of sterol biosynthesis inhibitors. Quinuclidines inhibit the leishmanial SSN, disrupt endogenous sterol biosynthesis and cause the inhibition of the growth of the leishmanial parasite (Lorente et al., 2005; Rodrigues et al., 2005; Cammerer et al., 2007). E5700, an inhibitor of SSN, has been tested in a murine model of chagas disease and is able to provide complete protection against death and completely suppress parasitimia (Urbina et al., 2004; Rodrigues et al., 2008). Studies related to structure–function relationship may lead to a better understanding of this potential drug target. We have cloned, overexpressed the Leishmania donovani SSN gene in pET-28(a) transformed in Escherichia coli and designated

as LdSSN. This recombinant L. donovani SSN enzyme was purified and biochemically characterized. Here, we describe, for the first time, Glutamate dehydrogenase partial purification of full-length LdSSN through anion exchange chromatography followed by hydrophobic interaction chromatography and finally validated by Western blot. Biochemical properties such as pH optimum, thermal stability and the effect of denaturants on LdSSN are reported here. Farnesyl pyrophosphate (FPP) unlabelled, squalene unlabelled, 2-mercaptoethanol, NADPH, phenylmethylsulfonyl fluoride (PMSF) and Zaragozic acid A (microbial origin) were obtained from Sigma-Aldrich. Restriction enzymes used for cloning were obtained from MBI, Fermentas. Monoclonal His-antibody and Ni-NTA superflow were obtained from Qiagen. pGEM-T Easy cloning vector was purchased from Promega.

In particular, the robust paired-pulse facilitation characteristi

In particular, the robust paired-pulse facilitation characteristic of adult neurons is almost entirely lacking in newborns. To examine developmental changes in processes controlling [Ca2+]res, we measured the timecourse of [Ca2+]res decay in presynaptic terminals of Schaffer collateral to CA1 synapses in acute hippocampal slices following single and paired orthodromic stimuli in the stratum radiatum. PLX4032 in vivo Developmental changes were observed

in both the rise time and slow exponential decay components of the response to single stimuli such that this decay was larger and faster in the adult. Furthermore, we observed a greater caffeine-sensitive basal Ca2+ store, which was differentially affected when active uptake into the endoplasmic reticulum was blocked, in the presynaptic fields of the Schaffer collateral to CA1 terminals of P6 and younger mice when compared to adults. These transitions in [Ca2+]res dynamics occurred gradually over the first weeks of postnatal life and correlated with changes in short-term plasticity. “
“Several transcranial magnetic stimulation (TMS) studies have reported facilitation of the primary motor cortex (M1) during the mere observation of actions. This facilitation was shown to be highly congruent, in terms of somatotopy, with the observed action, even at the level of single muscles. With

the present study, we investigated whether this muscle-specific facilitation of the observer’s motor system reflects the degree of muscular force that is Olaparib concentration exerted in an observed action. Two separate TMS experiments are reported in which corticospinal excitability was measured in the hand area of M1 while subjects observed the lifting of objects of different weights. The type of action ‘grasping-and-lifting-the-object’ was always identical, but the grip force varied according to the object’s weight. In accordance Lck to previous findings, excitability of M1 was shown to modulate in a muscle-specific way, such that

only the cortical representation areas in M1 that control the specific muscles used in the observed lifting action became increasingly facilitated. Moreover, muscle-specific M1 facilitation was shown to modulate to the force requirements of the observed actions, such that M1 excitability was considerably higher when observing heavy object lifting compared with light object lifting. Overall, these results indicate that different levels of observed grip force are mirrored onto the observer’s motor system in a highly muscle-specific manner. The measured force-dependent modulations of corticospinal excitability in M1 are hypothesized to be functionally relevant for scaling the observed grip force in the observer’s own motor system. In turn, this mechanism may contribute, at least partly, to the observer’s ability to infer the weight of the lifted object.

Clostridium thermocellum is a Gram-positive, anaerobic, thermophi

Clostridium thermocellum is a Gram-positive, anaerobic, thermophilic, cellulolytic bacterium, capable of converting cellulosic substrates directly into soluble sugars

and fermentation products, for example, ethanol and molecular hydrogen. These qualities render C. thermocellum potentially useful for producing renewable forms of energy from plant-derived biomass, and hence interest in this bacterium has increased tremendously in recent years. Clostridium thermocellum has become a model organism for cellulose degradation by virtue of its production of the multienzyme cellulosome complex for this purpose (Lamed et al., 1983; reviewed by Bayer et al., 2004). The key feature of the cellulosome is the nonhydrolytic ‘scaffoldin’ subunit that integrates the various catalytic subunits into the complex through interactions PF-02341066 nmr between its repetitive ‘cohesin’ modules and a complementary ‘dockerin’ module borne by each of the catalytic subunits. The scaffoldin subunit

can integrate a consortium of nine different catalytic subunits per complex, but the genome encodes for >70 different dockerin-containing components, thereby producing a heterogeneous mixture of individual complexes that differ in their enzyme composition. The attachment of the cellulosome to its substrate Selleckchem LY2109761 is mediated by a carbohydrate-binding module (CBM) that comprises part of the scaffoldin subunit. In previous studies, the expression profiles of some C. thermocellum genes that encode cellulosomal enzymes and structural proteins were analyzed. It was observed that up- or downregulation of these genes was strongly dependent on the carbon sources mafosfamide present in the growth media (Dror et al., 2003a, b, 2005; Stevenson & Weimer, 2005; Gold & Martin, 2007; Raman et al., 2009). Moreover, the transcriptional start sites of some of these genes have been mapped, and putative promoter sequences were analyzed (Dror et al., 2003a, 2005). To date,

however, the mechanism(s) by which C. thermocellum senses its environment and controls the expression of the abovementioned genes is still unknown. One of the main regulatory mechanisms in bacteria is based on so-called alternative RNA polymerase (RNAP) σ factors (Lonetto et al., 1992; Helmann, 2002). In general, alternative σ factors control specialized regulons active during growth transitions, in the stationary phase, in response to stress conditions or during morphological differentiation (Helmann, 2002). Among the alternative σ factors, there is a large subfamily of the extracytoplasmic function (ECF) σ factors (Lonetto et al., 1994; Staroñet al., 2009), of which many bacteria contain multiple copies (Helmann, 2002; Paget & Helmann, 2003). The roles and mechanisms of the regulation of these various ECF σ factors are largely unknown.

5a) In the control strain, approximately 70% of hyphae contained

5a). In the control strain, approximately 70% of hyphae contained stained Spk 30 min after the initial staining (Fig. 5b and c), which increased to 90% after 60 min (Fig. 5b). In contrast, in the

aipA-overexpressing strain, approximately 35% of hyphae with stained Spk were observed 30 min after the staining (Fig. 5b and c), which only increased to 50% after 60 min (Fig. 5b). Notably, the mutant aipA-overexpressing strains showed nearly identical Spk staining as that of the control this website strain (Fig. 5b and c). Taken together, these results suggest that the endocytic recycling of FM4-64 to Spk is both defective and delayed in the aipA-overexpressing strain. However, because the aipA-overexpressing strain also displayed impaired growth, it is possible that the Spk was not present in certain hyphae,

and thus, the relative rate of endocytic recycling was not substantially delayed in this strain. To exclude this possibility, we calculated the half-time required for Spk staining with FM4-64 for each of the strains (Fig. 5d). The half-time for staining in the aipA-overexpressing strain was clearly longer than that in the control and mutant aipA-overexpressing strains, indicating that the check details aipA-overexpressing strain has defects with respect to endocytic recycling; this delay could be caused by the defect of endocytosis, that of trafficking of vesicles to Spk, or both. We also confirmed that there was no significant difference between the control and the ΔaipA strains in this analysis (data not shown). In this study, we discovered a putative

AAA ATPase, AipA, as a binding partner of AoAbp1 by YTH screening. Although the ΔaipA strain did not display growth or endocytic defects, the aipA-overexpressing strain showed impaired growth, abnormal hyphal morphology, and a deficiency in the endocytic recycling of FM4-64, whereas the mutant aipA-overexpressing strains did not. The subsequent localization and functional analyses using the aipA-overexpressing strain suggested that AipA negatively functions PDK4 in endocytic recycling at the tip region of A. oryzae. There seems to be one AipA ortholog in filamentous fungi and two in yeasts. Both Sap1p and Yta6p, S. cerevisiae AipA orthologs, are putative AAA ATPases, but their molecular function is unknown. Sap1p was found by the YTH analysis as a binding protein with Sin1p, a transcriptional repressor (Liberzon et al., 1996). Yta6p is one of 12 YTA family proteins and is localized at the cortex in mother cells, but not in daughter cells (Schnall et al., 1994; Beach & Bloom, 2001). Single disruptants of either SAP1 or YTA6 are viable and no remarkable phenotypic alteration has been reported.

cocaine self-administration) with brain region group as a repeate

cocaine self-administration) with brain region group as a repeated measure. These were followed by planned Bonferroni’s tests for multiple comparisons. Statistical significance was considered

at P < 0.05. Animals self-administered cocaine (1.5 mg/kg per injection) for five consecutive days with a daily maximum of 40 total injections (all animals self-administered the maximum each day). Injections were limited to ensure that all animals had the same intake over each self-administration session to control for total intake as a factor in the functional effects of cocaine. Because of this limit on the number of daily injections, animals quickly reached the maximum total daily intake (60 mg/kg) and could not exceed that. However, animals could control the rate of intake over the sessions buy BEZ235 (Fig. 1).

Similar to previous studies this rate increased over the 5-day Daporinad in vitro period (Mateo et al., 2005; Calipari et al., 2012; Ferris et al., 2012). One-way anova revealed a main effect of session (F4,56 = 14.93, P < 0.001). Tukey's post hoc analysis revealed an increase in rate vs. the first session on sessions two (q = 4.216, P < 0.05), three (q = 5.843, P < 0.01), four (q = 8.734, P < 0.001) and five (q = 9.673, P < 0.0001). Following cocaine self-administration, behavioral activity was assessed using automated monitors. Our a priori hypothesis was that locomotor activity in response to a novel environment would be reduced following cocaine self-administration (Koeltzow & White, 2003). Two-way anova revealed a main effect of Acesulfame Potassium cocaine self-administration on the response to a novel environment (F1,75 = 4.04, P < 0.05). In addition, there was a main effect of time (F5,75 = 73.53, P < 0.0001) as animals habituated to the activity chamber. There were no significant differences between the groups in either stereotypy or vertical activity. Bonferroni's tests for multiple comparisons were performed

to compare across treatment groups, and a reduction in locomotor activity was observed at the 15-min time point in animals that had undergone cocaine self-administration (t = 3.219, P < 0.05; Fig. 2). Alternatively, we found a significant effect of time (F17,204 = 17.64 P < 0.001), but not of treatment (F1,204 = 0.05, NS) or an interaction (F17,204 = 8.93, NS) on saline-induced locomotion, indicating that normal forward locomotion was not impaired by a prior cocaine self-administration history (Fig. 3). To determine whether other measures of locomotor behavior had changed as a consequence of cocaine self-administration and withdrawal, we assessed vertical activity and stereotypy-like behavior. Student’s t-test revealed that cocaine self-administration animals had higher vertical counts as compared with controls (t12 = 7.604, P < 0.0001; Fig. 4). In addition, cocaine self-administration animals had lower stereotypy counts as compared with controls (t12 = 3.988, P < 0.0001; Fig. 4).

Our task was similar to directed forgetting designs (Baddeley et 

Our task was similar to directed forgetting designs (Baddeley et al., 2009) when memory for ‘to-be-forgotten’ items is weaker, but regularly above chance level. The above-chance level of performance for distractor letters suggests reliable

responses (i.e. extreme below-chance performance might suggest that participants intentionally did not report distractor letters that they remembered). One may assume that participants simply knew that the distractor will be asked and thus attempted to remember it better and with it they encoded the scenes. However, our results do not indicate that participants attempted to remember the distractor-associated scenes better because scene recognition performance was at the chance level in this condition, which was similar to the case when scenes were presented Navitoclax alone. Moreover, in the dopamine replacement condition, a boosting effect was observed for the recognition of distractor-associated scenes but not for the recall of distractor letters, which indicates an intriguing dissociation between the recall of the central stimulus (letters) and the recognition of the background information (scenes).

A possible explanation may be that the short-term memory systems responsible for maintaining the letters and the neural systems responsible for the attentional boost are not equally affected by PD and dopaminergic medications, and that medicated patients with PD have less control Z VAD FMK over distracting items (e.g. Moustafa et al., 2008). The Evodiamine neuronal correlates of attentional boost and its pharmacological modulation need to be investigated using functional neuroimaging methods. Swallow et al. (2012) provided evidence

that responding to target stimuli at behaviorally relevant points of time enhanced activity in early visual cortical areas, but it is not clear how it affects memory for contextual background images. Although our current results and data from individuals with hippocampal atrophy (Szamosi et al., 2013) suggest the relevance of midbrain dopaminergic–hippocampal interactions in attentional boost (Shohamy & Wagner, 2008; Wimmer et al., 2012), this hypothesis should be directly tested. This study was supported by the National Development Agency (TÁMOP-4.2.2.A-11/1/KONV-2012-0052). Abbreviations ABT attentional boost test ANT attention network test BIS-11 Barratt Impulsiveness Scale-11 HAM-D Hamilton Depression Rating Scale HSD Honestly Significant Difference L-DOPA l-3,4-dihydroxyphenylalanine LED levodopa equivalent dose MIDI Minnesota Impulsive Disorders Interview PD Parkinson’s disease SOGS South Oaks Gambling Screen UPDRS Unified Parkinson’s Disease Rating Scale The authors (S.K., H.N., E.L.G., O.K.) declare no conflict of interest. “
“Several studies have already shown that transcranial direct current stimulation (tDCS) is a useful tool for enhancing recovery in aphasia. However, all tDCS studies have previously investigated the effects using unihemisperic stimulation.

To clone all three initiation factors under control of the BAD pr

To clone all three initiation factors under control of the BAD promoter, coding regions were amplified from the DH5α chromosome and cloned into the

NotI and XbaI sites of pKAN6. The 5′- primers contained the same ribosome-binding site and spacer to ensure the same level of protein expression. The primer sequence U0126 is as follows: 5′-GGCATGCGCGGCCGCAATAATTTTGTTTAACTTTAAGAAGAGATATACCATG plus 17 nucleotides of the gene-specific sequence (the start codon is underlined). The 3′- primers had the same sequence, except for the sequence corresponding to the coding region, namely 5′-GGATCCTCTAGATTA plus 17 nucleotides of the gene-specific sequence (the stop codon is underlined). MICs were determined as described previously (Lee et al., 1996). Western blot analysis of the CAT protein and Antidiabetic Compound Library supplier IF1 was performed as described previously (Cummings & Hershey, 1994; Kim et al., 2009). Ribosome purification and primer extension analysis were performed as described previously (Lee et al., 1996; Kim et al., 2009). To investigate the functional role played by G791 during the process of protein synthesis, we adopted a novel genetic approach using the specialized ribosome system (Lee et al., 1997, 2001). In the specialized ribosome system used in this study, the chloramphenicol acetyltransferase (CAT) reporter message is translated exclusively by plasmid (pRNA122)-derived ribosomes (pRNA122 ribosomes),

which cannot translate normal cellular messages. Thus, it is possible to measure the function of the plasmid-derived mutant ribosomes in vivo by determining the amount of CAT protein synthesized in cells that express the mutant BCKDHA ribosomes. This specialized ribosome system offers a genetic method to select for mutants that restore CAT protein synthesis ability to mutant ribosomes, because the degree of resistance to chloramphenicol (Cm) of cells is proportional to the CAT activity or the amount of CAT protein produced in the cells by the mutant ribosomes (Lee et al., 1997, 2001; Song et al., 2007;

Kim et al., 2009). We suspected the involvement of the 790 loop in interaction with ligands involved in translation because of the accessibility of the loop to solvents and the structural features of bases at positions 789–791. Consequently, we considered the possibility that a base substitution at position 791 may cause a structural perturbation in the 790 loop that prevents the 30S ribosome from interacting with ligands. To examine this possibility, we used a genetic complementation approach to identify such ligands. A genomic library was constructed in pKAN3 using Escherichia coli genomic DNA from the DH5α strain partially digested with EcoRI. This plasmid contains a replication origin from pACYC177 (Chang & Cohen, 1978) and a deletion of bla. Constructs of this vector are compatible with the pRNA122 plasmid, which is a pBR322 derivative.

The integrity of an in vitro model of BBB comprising HBMECs and

The integrity of an in vitro model of BBB comprising HBMECs and

astrocytes was studied by measuring transendothelial electrical resistance and the paracellular flux of albumin. OGD with or without reperfusion (OGD ± R) radically perturbed barrier function while concurrently enhancing uPA, tPA and NAD(P)H oxidase activities and superoxide anion release in HBMECs. Pharmacological inactivation of NAD(P)H oxidase attenuated OGD ± R-mediated BBB damage through modulation of matrix metalloproteinase-2 and tPA, but not uPA activity. Overactivation of NAD(P)H oxidase in HBMECs via cDNA electroporation of its p22-phox subunit confirmed the involvement of tPA Veliparib cost in oxidase-mediated BBB disruption. HDAC inhibitor Interestingly, blockade of uPA or uPA receptor preserved normal BBB function by neutralizing both NAD(P)H oxidase and matrix metalloproteinase-2 activities. Hence, selective targeting of uPA after ischaemic strokes may protect cerebral barrier integrity and function by concomitantly attenuating basement membrane degradation and oxidative stress. “
“In 19 healthy volunteers, we used transcranial magnetic stimulation (TMS) to probe the excitability in pathways linking the left dorsal premotor cortex and

right primary motor cortex and those linking the left and right motor cortex during the response delay and the reaction time period while subjects performed a delayed response [symbol 1 (S1) - symbol 2 (S2)] Go–NoGo reaction time task with visual cues. Conditioning TMS pulses were applied to the left premotor or left Dichloromethane dehalogenase motor cortex 8 ms before a test pulse was given to the right motor cortex at 300 or 1800 ms after S1 or 150 ms after S2. S1 coded for right-hand or left-hand movement, and S2 for release or stopping the prepared movement. Conditioning of the left premotor

cortex led to interhemispheric inhibition at 300 ms post-S1, interhemispheric facilitation at 150 ms post-S2, and shorter reaction times in the move-left condition. Conditioning of the left motor cortex led to inhibition at 1800 ms post-S1 and 150 ms post-S2, and slower reaction times for move-right conditions, and inhibition at 300 and 1800 ms post-S1 for move-left conditions. Relative motor evoked potential amplitudes following premotor conditioning at 150 ms post-S2 were significantly smaller in ‘NoGo’ than in ‘Go’ trials for move-left instructions. We conclude that the excitability in left premotor/motor right motor pathways is context-dependent and affects motor behaviour. Thus, the left premotor cortex is engaged not only in action selection but also in withholding and releasing a preselected movement generated by the right motor cortex. “
“Acoustic speech is easier to detect in noise when the talker can be seen.

The interpretation of resistance test results is complex

The interpretation of resistance test results is complex. http://www.selleckchem.com/products/ch5424802.html Although informative interpretation systems have been developed for both genotypic and phenotypic results, none is entirely accurate, and all are subject to change as new data become available. Interpretation is especially difficult with new drugs and this problem affects both genotypic and phenotypic resistance assays. Expert advice should be sought with complex or unusual resistance profiles. Sufficient information on treatment history should be provided to optimize interpretation of resistance test results in the laboratory. Viraemia should be confirmed before performing a resistance test in treated patients (IV).

However, further assessment should be undertaken promptly because of the risk of accumulation of mutations, particularly in patients taking regimens with a low genetic barrier (IIb). Resistance testing is recommended in all treated patients experiencing confirmed viraemia and changes in therapy should be guided by the results of resistance testing in these patients (Ia). For patients showing viraemia while receiving integrase inhibitors or enfuvirtide Pexidartinib research buy (T20), resistance testing should be undertaken promptly in laboratories offering the

tests (IIb). For patients experiencing viraemia while receiving CCR5 antagonists, repeat tropism testing should be performed (Ia). If the virus is confirmed as R5, the presence of resistance to CCR5 antagonists should be suspected (Ia), although testing for this is not routinely available at present. The level of viraemia at which resistance testing can be performed reliably is just above 50 copies/mL in many specialized laboratories. Resistance testing where viral load levels are less than 1000 copies/mL can provide useful information and clinicians are encouraged to discuss and agree the required viral load cut-off for testing Cyclin-dependent kinase 3 with their service providers (IV). Laboratories should review the optimal methodology for resistance testing at low viral load levels (III). Resistance testing should preferably be performed on samples taken while the patient is still on therapy (IIb). Resistance testing by routine methods is not

recommended after unstructured interruption of NNRTIs because of suboptimal sensitivity in this context (IIa), although selection of NNRTI resistance should be considered possible (IIb). Resistance test results should be interpreted in the context of the patient’s entire treatment history and the results of all tests performed in a patient should be taken into account to guide optimal treatment selection (IIb). On the basis of the viral nucleic acid sequence, HIV-1 has been subdivided into nine subtypes (A–D, F–H, J and K). It is thought that these diversified soon after HIV-1 group M was established in the human population. Subsequently, as a result of dual infection or superinfection, recombinant viruses, with genomes composed of more than one subtype, emerged.