Optimized Kalinnikov-Dinh technology for effective pre-Descemet's endothelial keratoplasty (PDEK) graft preparation and preservation.

We report an optimized Kalinnikov-Dinh technology for pre-Descemet's endothelial keratoplasty (PDEK) that involves the use of a ring fixator, base, 30G needle connected to a 5-ml syringe with a spring-loaded plunger, and storage media. Our method allows to minimize graft preparation failure and preserves the PDEK graft efficiently, by reducing complications associated with the formation of type 1 big bubbles, including bubble rupture, perforation of Descemet's membrane and endothelium, and formation of type 2 or mixed type of big bubbles, and may contribute to increasing the number of surgeons performing PDEK around the globe.

[Surgical technique of keratoplasty with simultaneous implantation of a continuous ring or ring segment into the graft]. / Khirurgicheskaya tekhnika keratoplastiki s odnomomentnoi implantatsiei tsel'nogo ili razomknutogo kol'tsa v transplantat.

The article presents the surgical technique of penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK) with femtosecond-laser assistance involving simultaneous implantation of an intracorneal continuous ring (ICCR) or an intracorneal ring segment (ICRS) into the graft. Surgical technique no. 1 - keratoplasty with simultaneous implantation of ICRS. Intrastromal circular tunnel is formed in the central zone of donor cornea using femtosecond laser. Then penetrating trepanation 8.1 mm in diameter is performed symmetrically to the formed tunnel. After preparing penetrating or lamellar recipient bed, suture fixation is placed in the corneal transplant, then the ICRS is implanted into the graft. Surgical technique no. 2 - keratoplasty with simultaneous implantation of ICCR. The donor cornea is dissected from periphery to center using femtosecond laser. Central zone remains untouched. A large diameter full-thickness trepanation is performed and the donor cornea is divided into the anterior and posterior layers. The ICCR is put on the donor cornea while holding the posterior layer with forceps. Penetrating or lamellar recipient bed is prepared, then the corneal graft is fixed with sutures. Transparent corneal graft acceptance does not guarantee high visual acuity due to post-keratoplasty astigmatism. Surgical correction of astigmatism is performed in the long term post-operatively and isn't effective enough. We proposed this new surgical technique of keratoplasty with simultaneous implantation of ICCR and ICRS into the graft as close as possible to the visual axis of the eye, which can help make the postoperative astigmatism minimal both immediately after surgery and in the long term. The study proposes a new approach to intraoperative prevention of post-keratoplasty astigmatism. The technique is simple, safe and effective. Analysis of long-term outcomes is required before recommending this method for widespread use in clinical practice.

[A new surgical approach to pre-Descemet's endothelial keratoplasty]. / Novyi khirurgicheskii podkhod k predestsemetovoi endotelial'noi keratoplastike (PDEK).

PURPOSE: The study aimed to develop new surgical methods of obtaining and preserving pre-Descemet's endothelial keratoplasty (PDEK) graft in order to reduce the loss of donor material. MATERIAL AND METHODS: The study was conducted on 30 sclerocorneal discs, which were divided into three groups. The first group consisted of 10 sclerocorneal discs to which the standard PDEK graft preparation technique was applied. The second group consisted of 10 sclerocorneal discs, where the PDEK graft preparation was done using the optimized method 1 involving the KD Ring fixator, KD Base for PDEK, KD-30G needle with 5 mL syringe connected to the spring-load plunger, a preservative solution. The third group consisted of 10 sclerocorneal discs with PDEK graft prepared using the optimized method 2, which differed from the optimized method 1 in additional use of the KD artificial chamber for PDEK. When successfully acquiring the type-1 "big bubble", the dissected PDEK graft was preserved for further use in clinical practice using our own technique. RESULTS: In the first group, formation of the type-1 «big bubble¼ was achieved only in 5 out of 10 donor corneas (50%). Bubble ruptures happened in 4 cases (40%) and type-2 «big bubble¼ occurred in 1 case (10%). In the second group (optimized method 1) the type-1 «big bubble¼ was achieved in 9 cases (90%), while in the third group (optimized method 2) the type-1 «big bubble¼ was achieved in 10 cases (100%), proving the effectiveness of our PDEK graft preparation technique. CONCLUSION: We presented a novel surgical approach for acquiring and preserving PDEK graft that minimizes almost all the difficulties that surgeons face, including bubble rupture during pneumodissection and hydrodissection, formation of type-2 and mixed type bubble, and obtaining a PDEK graft of the required size; the details of the surgical technique have been refined. The proposed technique for graft preparation and preservation can be easily implemented in eye banks and is convenient for clinical practice.

Vexitoxins: conotoxin-like venom peptides from predatory gastropods of the genus Vexillum.

Venoms of predatory marine cone snails are intensely studied because of the biomedical applications of the neuropeptides that they contain, termed conotoxins. Meanwhile some gastropod lineages have independently acquired secretory glands strikingly similar to the venom gland of cone snails, suggesting that they possess similar venoms. Here we focus on the most diversified of these clades, the genus Vexillum. Based on the analysis of a multi-species proteo-transcriptomic dataset, we show that Vexillum species indeed produce complex venoms dominated by highly diversified short cysteine-rich peptides, vexitoxins. Vexitoxins possess the same precursor organization, display overlapping cysteine frameworks and share several common post-translational modifications with conotoxins. Some vexitoxins show sequence similarity to conotoxins and adopt similar domain conformations, including a pharmacologically relevant inhibitory cysteine knot motif. The Vexillum envenomation gland (gL) is a notably more recent evolutionary novelty than the conoidean venom gland. Thus, we hypothesize lower divergence between vexitoxin genes, and their ancestral 'somatic' counterparts compared to that in conotoxins, and we find support for this hypothesis in the evolution of the vexitoxin cluster V027. We use this example to discuss how future studies on vexitoxins can inform the origin of conotoxins, and how they may help to address outstanding questions in venom evolution.

Intracorneal knot or flange depot fixation: new transscleral technique for intraocular lens fixation.

A new surgical technique of transscleral-intracorneal suture fixation of intraocular lenses with suture ends located within the transparent corneal or corneal-limbal paracentesis is reported. This new technique significantly reduces scleral and conjunctival trauma, is minimally invasive, is simple to perform, is not associated with complicated intraocular surgical maneuvers, and precludes suture knot, flange, and suture-end erosion. The internal part of the corneal stroma or corneal-limbal area serves as a secure depot for suture-end fixation with durable resistance. The technique enables visualization of the exact position of suture ends over time.

Uptake of antenatal care in high HIV-prevalence settings: Results from three population-based surveys in South Africa.

BACKGROUND: Despite substantial progress in reducing pregnancy-related preventable morbidity and mortality, these remain unacceptably high in developing countries. In 2016, the World Health Organization (WHO) revised recommendations for antenatal care (ANC) from a 4-visit model to a minimum of 8 ANC contacts to reduce perinatal mortality further and improve women's experience of care. The guidelines also recommend that the first ANC visit (ANC-1) should occur during the first trimester. OBJECTIVES: To describe the uptake of routine ANC and its associated factors in South Africa (SA) prior to the 2016 WHO recommendations, when the country recommended 4 ANC visits, to bring to light potential challenges in achieving the current recommendations. METHODS: Secondary data analyses were performed from 3 facility-based, cross-sectional national surveys, conducted to measure 6-week mother-to-child transmission of HIV and coverage of related interventions in SA. These surveys recruited mother-infant pairs attending selected public primary healthcare facilities for their infants' 6-week immunisation in 2010, 2011 -2012 and 2012 -2013. Quantitative questionnaires were used to gather sociodemographic and antenatal-to-peripartum information from Road to Health cards and maternal recall. The inclusion criteria for this secondary assessment were at least 1 ANC visit, the primary outcome being uptake of ≥4 ANC visits. A multivariable logistic regression model was used to: (i) identify maternal factors associated with ANC visits; and (ii) establish whether receiving selected ANC activities was associated with frequency or timing of ANC-1. RESULTS: Of the 9 470, 9 646 and 8 763 women who attended at least 1 ANC visit, only 47.5% (95% confidence interval (CI) 45.4 -49.6), 55.6% (95% CI 53.2 -58.0) and 56.7% (95% CI 54.3 -59.1) adhered to ≥4 ANC visits, while 36.0% (95% CI 34.5 -37.5), 43.5% (95% CI 42.0 -45.1) and 50.8% (95% CI 49.3 -52.2) attended ANC-1 early (before 20 weeks' gestation) in 2010, 2011 -2012 and 2012 -2013, respectively. Multiparity and lower socioeconomic status were significantly associated with non-adherence to the 4-visit ANC recommendation, while a later survey year, higher education, being married, >19 years old, HIV-positive, planned pregnancy and knowing how HIV is transmitted vertically were strongly related to ≥4 ANC visits. The number of women who received selected ANC activities increased significantly with survey year and ≥4 ANC visits, but was not associated with timing of ANC-1. CONCLUSIONS: Despite increases in the uptake of ≥4 ANC visits and early ANC-1 rates between 2010 and 2013, these practices remain suboptimal. Adhering to ≥4 ANC visits improved coverage of selected ANC activities, implying that strengthening efforts to increase the uptake of ANC from at least 4 to 8, could improve overall outcomes.

Parametric attosecond pulse amplification far from the ionization threshold from high order harmonic generation in He.

Parametric amplification of attosecond coherent pulses around 100 eV at the single-atom level is demonstrated for the first time by using the 3D time-dependent Schrödinger equation in high-harmonic generation processes from excited states of He+. We present the attosecond dynamics of the amplification process far from the ionization threshold and resolve the physics behind it. The amplification of a particular central photon energy requires the seed XUV pulses to be perfectly synchronized in time with the driving laser field for stimulated recombination to the He+ ground state and is only produced in a few specific laser cycles in agreement with the experimental measurements. Our simulations show that the amplified photon energy region can be controlled by varying the peak intensity of the laser field. Our results pave the way to the realization of compact attosecond pulse intense XUV lasers with broad applications.

Enhanced sensitivity and responses to viologens from a whole-cell bacterial bioreporter treated with branched polyethyleneimines.

AIMS: Evaluate the use of polyethyleneimines (PEIs) as membrane permeabilizers to improve the responses and sensitivity of a bacterial bioreporter strain to viologens. METHODS AND RESULTS: The responses from E. coli str. EBS, i.e., E. coli BW25113 carrying plasmid pSDS, when exposed to five different viologens were characterized, as were the toxicities of seven different PEIS, including two linear and five branched species. Based on these results, benzyl viologen led to the greatest responses, and 0·8-kDa branched PEI (BPEI) was the least toxic of the PEIs tested and, therefore, both were selected for the subsequent tests. The bioluminescence and relative responses from E. coli str. EBS exposed to various concentrations of 0·8 kDa BPEI identified 400 mg l-1 as the optimal concentration. Using this concentration, tests were performed with all five of the viologens. CONCLUSIONS: The responses from E. coli str. EBS to the viologens were improved, with the maximum relative bioluminescence values increasing between 5·6 and 16·5-fold. The minimum detectable levels for four of the viologens were likewise improved 2- to 4-fold. SIGNIFICANCE AND IMPACT OF STUDY: Improving bacterial membrane permeability in a controlled manner using BPEIs can improve biosensing of toxic compounds, as well as be used in biofuel and bioenergy applications where membrane permeability to a solute is important.

Development of solar concentrators for high-power solar-pumped lasers.

We have developed unique solar concentrators for solar-pumped solid-state lasers to improve both efficiency and laser output power. Natural sunlight is collected by a primary concentrator which is a 2 m×2 m Fresnel lens, and confined by a cone-shaped hybrid concentrator. Such solar power is coupled to a laser rod by a cylinder with coolant surrounding it that is called a liquid light-guide lens (LLGL). Performance of the cylindrical LLGL has been characterized analytically and experimentally. Since a 14 mm diameter LLGL generates efficient and uniform pumping along a Nd:YAG rod that is 6 mm in diameter and 100 mm in length, 120 W cw laser output is achieved with beam quality factor M2 of 137 and overall slope efficiency of 4.3%. The collection efficiency is 30.0 W/m2, which is 1.5 times larger than the previous record. The overall conversion efficiency is more than 3.2%, which can be comparable to a commercial lamp-pumped solid-state laser. The concept of the light-guide lens can be applied for concentrator photovoltaics or other solar energy optics.

Truncated Cables1 causes agenesis of the corpus callosum in mice.

Agenesis of the corpus callosum (ACC) is a congenital abnormality of the brain structure. More than 60 genes are known to be involved in corpus callosum development. However, the molecular mechanisms underlying ACC are not fully understood. Previously, we produced a novel transgenic mouse strain, TAS, carrying genes of the tetracycline-inducible expression system that are not involved in brain development, and inherited ACC was observed in the brains of all homozygous TAS mice. Although ACC was probably induced by transgene insertion mutation, the causative gene and the molecular mechanism of its pathogenesis remain unclear. Here, we first performed interphase three-color fluorescence in situ hybridization (FISH) analysis to determine the genomic insertion site. Transgenes were inserted into chromosome 18 ∼12.0 Mb from the centromere. Gene expression analysis and genomic PCR walking showed that the genomic region containing exon 4 of Cables1 was deleted by transgene insertion and the other exons of Cables1 were intact. The mutant allele was designated as Cables1(TAS). Interestingly, Cables1(TAS) mRNA consisted of exons 1-3 of Cables1 and part of the transgene that encoded a novel truncated Cables1 protein. Homozygous TAS mice exhibited mRNA expression of Cables1(TAS) in the fetal cerebrum, but not that of wild-type Cables1. To investigate whether a dominant negative effect of Cables1(TAS) or complete loss of function of Cables1 gives rise to ACC, we produced Cables1-null mutant mice. ACC was not observed in Cables1-null mutant mice, suggesting that a dominant negative effect of Cables1(TAS) impairs callosal formation. Moreover, ACC frequency in Cables1(+/TAS) mice was significantly lower than that in Cables1(-/TAS) mice, indicating that wild-type Cables1 interfered with the dominant negative effect of Cables1(TAS). This study indicated that truncated Cables1 causes ACC and wild-type Cables1 contributes to callosal formation.

120 watt continuous wave solar-pumped laser with a liquid light-guide lens and an Nd:YAG rod.

We propose a simple and efficient pumping approach for a high-power solar-pumped laser by using a liquid light-guide lens (LLGL) and a hybrid pumping cavity. A 2×2 m Fresnel lens is used as a primary concentrator to collect natural sunlight; 120 W cw laser power and a 4.3% total slope efficiency are achieved with a 6-mm diameter Nd:YAG rod within a 14-mm diameter LLGL. The corresponded collection efficiency is 30.0 W/m(2), which is 1.5 times larger than the previous record. This result is unexpectedly better than that of Cr:Nd:YAG ceramics. It is because the scattering coefficient of Cr:Nd:YAG ceramics is 0.004cm(1), which is 2 times larger than that of the Nd:YAG crystal, although both have similar saturation gains.

Molecular determinants of apoptosis induced by the cytotoxic ribonuclease onconase: evidence for cytotoxic mechanisms different from inhibition of protein synthesis.

Cytotoxic endoribonucleases (RNases) possess a potential for use in cancer therapy. However, the molecular determinants of RNase-induced cell death are not well understood. In this work, we identify such determinants of the cytotoxicity induced by onconase, an amphibian cytotoxic RNase. Onconase displayed a remarkable specificity for tRNA in vivo, leaving rRNA and mRNA apparently undamaged. Onconase-treated cells displayed apoptosis-associated cell blebbing, nuclear pyknosis and fragmentation (karyorrhexis), DNA fragmentation, and activation of caspase-3-like activity. The cytotoxic action of onconase correlated with inhibition of protein synthesis; however, we present evidence for the existence of a mechanism of onconase-induced apoptosis that is independent of inhibition of protein synthesis. The caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp(OMe) fluoromethyl ketone (zVADfmk), at concentrations that completely prevent apoptosis and caspase activation induced by ligation of the death receptor Fas, had only a partial protective effect on onconase-induced cell death. The proapoptotic activity of the p53 tumor suppressor protein and the Fas ligand/Fas/Fas-associating protein with death domain (FADD)/caspase-8 proapoptotic cascade were not required for onconase-induced apoptosis. Procaspases-9, -3, and -7 were processed in onconase-treated cells, suggesting the involvement of the mitochondrial apoptotic machinery in onconase-induced apoptosis. However, the onconase-induced activation of the caspase-9/caspase-3 cascade correlated with atypically little release of cytochrome c from mitochondria. In turn, the low levels of cytochrome c released from mitochondria correlated with a lack of detectable translocation of proapoptotic Bax from the cytosol onto mitochondria in response to onconase. This suggests the possibility of involvement of a different, potentially Bax- and cytochrome c-independent mechanism of caspase-9 activation in onconase-treated cells. As one possible mechanism, we demonstrate that procaspase-9 is released from mitochondria in onconase-treated cells. A detailed understanding of the molecular determinants of the cytotoxic action of onconase could provide means of positive or negative therapeutic modulation of the activity of this potent anticancer agent.

Ultraviolet radiation triggers the ribotoxic stress response in mammalian cells.

The ribotoxic stress response, which is conserved between prokaryotes and eukaryotes, is a cellular reaction to cytotoxic interference with the function of the 3'-end of the large (23 S/28 S) ribosomal RNA. The 3'-end of the large rRNA is directly involved in the three sequential steps of translational elongation: the aminoacyl-tRNA binding, the peptidyl transfer, and the ribosomal translocation. In mammalian cells, the ribotoxic stress response involves activation of the stress-activated protein kinase/c-Jun NH2-terminal kinase and the p38 mitogen-activated protein kinase and transcriptional induction of immediate early genes such as c-fos and c-jun. Active ribosomes are essential mediators of the ribotoxic stress response. We demonstrate here that the transcriptional response of mammalian cells to ultraviolet radiation (UV response) displays the characteristics of a ribotoxic stress response, inasmuch as (i) the activation of stress kinases and gene expression in response to UV requires the presence of active ribosomes at the moment of irradiation; (ii) UV irradiation inhibits protein synthesis; and (iii) irradiation of cells with UV causes specific damage to the 3'-end of the 28 S rRNA. In contrast, the activation of the stress kinases by hyperosmolarity, by the DNA-cross-linking agent diepoxybutane, or by growth factors and cytokines does not depend on the presence of active ribosomes. Our results identify UV as a potential ribotoxic stressor and support the notion that some of the cellular signaling cascades in response to UV might be generated in the ribosome, possibly triggered by damage to rRNA.

Ribotoxic stress response: activation of the stress-activated protein kinase JNK1 by inhibitors of the peptidyl transferase reaction and by sequence-specific RNA damage to the alpha-sarcin/ricin loop in the 28S rRNA.

Inhibition of protein synthesis per se does not potentiate the stress-activated protein kinases (SAPKs; also known as cJun NH2-terminal kinases [JNKs]). The protein synthesis inhibitor anisomycin, however, is a potent activator of SAPKs/JNKs. The mechanism of this activation is unknown. We provide evidence that in order to activate SAPK/JNK1, anisomycin requires ribosomes that are translationally active at the time of contact with the drug, suggesting a ribosomal origin of the anisomycin-induced signaling to SAPK/JNK1. In support of this notion, we have found that aminohexose pyrimidine nucleoside antibiotics, which bind to the same region in the 28S rRNA that is the target site for anisomycin, are also potent activators of SAPK/JNK1. Binding of an antibiotic to the 28S rRNA interferes with the functioning of the molecule by altering the structural interactions of critical regions. We hypothesized, therefore, that such alterations in the 28S rRNA may act as recognition signals to activate SAPK/JNK1. To test this hypothesis, we made use of two ribotoxic enzymes, ricin A chain and alpha-sarcin, both of which catalyze sequence-specific RNA damage in the 28S rRNA. Consistent with our hypothesis, ricin A chain and alpha-sarcin were strong agonists of SAPK/JNK1 and of its activator SEK1/MKK4 and induced the expression of the immediate-early genes c-fos and c-jun. As in the case of anisomycin, ribosomes that were active at the time of exposure to ricin A chain or alpha-sarcin were able to initiate signal transduction from the damaged 28S rRNA to SAPK/JNK1 while inactive ribosomes were not.

[Everything is relative...about the Hanoi Institute of Traditional Medicine]. / Tout est relatif mais... à propos de l'Institut de Médecine Traditionnelle d'Hanoï.

At the Symposium entitled "Health, Culture, and Quality of Life" held in Hanoi in 1993, the authors of this report met the physicians in charge of the Traditional Medicine Institute of Hanoi which works with the World Health Organization for traditional medicine. After an historical overview of the foundation of this center providing research, care, and training under the auspices of the Hanoi School of Medicine, Professor Hoang Bao Chau described a practice based on revision of ancestral traditions in accordance with scientific methods, the resulting synthesis being up-to-date yet in keeping with heritage. This novel and pragmatic approach, which takes into account the complexity of man, offers an opportunity to reflect on the current status of medical practices in the world and on their adaptation to each population at a time when the experience of the Other seems almost impossible to communicate.

1H- and 31P-NMR studies of ditercalinium binding to a d(GCGC)2 and d(CCTATAGG)2 minihelices: a sequence specificity study.

The structures of the complexes formed in aqueous solution between ditercalinium, a bis-intercalating drug, and both the self-complementary tetranucleotide d(GCGC)2 and octanucleotide d(CCTATAGG)2, have been investigated by 400-MHz 1H-nmr and 162-MHz 31P-nmr. All the nonexchangeable protons, as well as the exchangeable imino protons and the phosphorus signals, have been assigned. Both oligonucleotides have been shown to adopt a right-handed B-DNA type structure. The addition of ditercalinium to the oligonucleotides lead to the formation of complexes in slow exchange at the nmr time scale with the free helices. At all drug-to-helix ratios studied, the ditercalinium was found in the bound form, whereas free and complexed oligonucleotides were in slow exchange, allowing resonance assignments through two-dimensional chemical exchange experiments. for d(GCGC)2 the strong upfield shifts induced on all aromatic protons of both the bases and the drug by complexation with ditercalinium suggest an interaction by intercalation of the two rings. However, the loss of twofold symmetry upon binding, as well as the chemical shift variation of the drug proton signals of one of the chromophores with temperature and concentration, favor a model in which the drug-nucleotide complexes have one ring of the drug intercalated and the other stacked on top of the external base pair. The intermolecular contacts between drug protons and nucleotide protons give a defined geometry for complexation that is consistent with the proposed model. In contrast, with d(CCTATAGG)2 several drug-nucleotide complexes were formed and a large increase in line broadening was observed at high drug-to-DNA ratios, precluding a detailed analysis of these complexes. However, the large upfield shift in the imino proton resonances together with the shielding of the ditercalinium ring protons favor a model with bis-intercalation of ditercalinium. This model is supported by the downfield shift of at least 4 out of 14 phosphorus signals. The results are compared with those obtained on ditercalinium binding to the homologous sequences d(CGCG)2 and d(TTCGCGAA)2, and discussed in terms of sequence specificity.

1H-NMR studies of a monointercalating drug into a d(CpGpApTpCpG)2 minihelix.

The structure of the complex formed between the 7H-pyridocarbazole monomer [[(2-piperidyl)-2,1-ethane-yl] [10-methoxy-7H-pyrido[4,3-c]carbazolium] dimethane sulfonate] and the autocomplementary hexanucleotide d(CpGpApTpCpG)2 in aqueous solution is analyzed by 270- and 400-MHz 1H-nmr. The large upfield shifts observed for both the drug and the self-complementary hexanucleotide protons provide evidence for intercalated complexes. The observation of intermolecular nuclear Overhauser effects between drug and the hexanucleotide protons gives a privileged orientation of the drug in the intercalation site with the quaternarizing ethyl piperidine chain protruding in the major groove. Moreover, the data suggest an intercalation based on the neighbor exclusion site principle in the three alternating sequences.

Bisintercalation of ditercalinium into a d(CpGpApTpCpG)2 minihelix: a 1H- and 31P-NMR study.

The structure of the complex formed in aqueous solution between ditercalinium, a bisintercalating drug, and the self-complementary hexanucleotide d(CpGpApTpCpG)2 is investigated by 400-MHz 1H-nmr and 162-MHz 31P-nmr. Whatever the drug to helix ratio, ditercalinium occurred in the bound form, whereas free and complexed hexanucleotide are in slow exchange. This allows unambiguous resonance assignment through two-dimensional chemical exchange experiments. The strong upfield shifts measured on most aromatic protons on both drug and bases as well as on DNA imino protons are consistent with bisintercalation of the dimer. Nuclear Overhauser effects observed between drug and nucleotide protons give a defined geometry for complexation, and suggest a DNA conformational change upon drug binding.

Independent transcriptional regulation of a single VL30 element by epidermal growth factor and activators of protein kinase C.

A single VL30 element present in the RVL-3 cell line was transcriptionally induced by both epidermal growth factor (EGF) and the protein kinase C (pkC) activators 12-O-tetradecanoylphorbol-13-acetate (TPA) and sn-1,2-dioctanoylglycerol within 5 min of stimulation. Following TPA-induced depletion of protein kinase C activity, EGF stimulation of VL30 transcription and accumulation was unaffected while TPA effects were inhibited, implying that EGF and TPA act by separable pathways.

Processing of complex heteroduplexes in Escherichia coli and Cos-1 monkey cells.

Upon transformation into Escherichia coli or Cos-1 monkey cells, heteroduplex DNA made of two sequences containing many nucleotide mismatches yields a wide array of different molecules, some with a patchwork structure. Thus, complex heteroduplexes can be processed to generate many genetic variants.