Correction to "Design and Synthesis of Ketenimine Sulfonamide Conjugates through Multicomponent Reactions; A Combined Cytotoxic Analysis and Computational Exploration"

[This corrects the article DOI: 10.1021/acsomega.3c05816.].

Stimuli-Responsive and Multifunctional Nanogels in Drug Delivery

Nanogels represent promising drug delivery systems in the biomedical field, designed to overcome challenges associated with standard treatment approaches. Stimuli-responsive nanogels, often referred to as intelligent materials, have garnered significant attention for their potential to enhance control over properties such as drug release and targeting. Furthermore, researchers have recently explored the application of nanogels in diverse sectors beyond biomedicine including sensing materials, catalysts, or adsorbents for environmental applications. However, to fully harness their potential as practical delivery systems, further research is required to better understand their pharmacokinetic behaviour, interactions between nanogels and bio distributions, as well as toxicities. One promising future application of stimuli-responsive multifunctional nanogels is their use as delivery agents in cancer treatment, offering an alternative to overcome the challenges with conventional approaches. This review discusses various synthetic methods employed in developing nanogels as efficient carriers for drug delivery in cancer treatment. The investigations explore, the key aspects of nanogels, including their multifunctionality and stimuli-responsive properties, as well as associated toxicity concerns. The discussions presented herein aim to provide the readers a comprehensive understanding of the potential of nanogels as smart drug delivery systems in the context of cancer therapy.

Block Copolymer Encapsulation of Disarib, an Inhibitor of BCL2 for Improved Chemotherapeutic Potential

A chemical inhibitor of antiapoptotic protein, BCL2, known as Disarib, suffers poor solubility in aqueous environments; thereby limiting its potential as a chemotherapeutic agent. To overcome this limitation and enhance the therapeutic efficacy of Disarib, we have employed the encapsulation of this small molecule inhibitor within P123 copolymer matrix. Micelles were synthesized using a thin-film hydration technique, and a comprehensive analysis was undertaken to evaluate the resulting micelle properties, including morphology, particle size, intermolecular interactions, encapsulation efficiency, and in vitro release characteristics. This assessment utilized various physicochemical techniques including UV spectroscopy, FTIR spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS). Disarib-loaded P123 micelle formulation denoted as P123D exhibited a well-defined particle size of approximately 29.2 nm spherical core-shell morphology. Our investigations revealed a notable encapsulation efficiency of 75%, and we observed a biphasic release pattern for the encapsulated Disarib. Furthermore, our cytotoxicity assessment of P123D micelles against mouse breast adenocarcinoma, mouse lymphoma, and human leukemic cell lines showed 40-45% increase in cytotoxicity compared with the administration of Disarib alone in the breast adenocarcinoma cell line. Enhancement in the cytotoxicity of P123D was found to be higher or limited; however, it is important to observe that the encapsulation method significantly enhanced the aqueous solubility of Disarib as it has the best solubility in dimethyl sulfoxide (DMSO) in the unencapsulated state.

Design and Synthesis of Ketenimine Sulfonamide Conjugates through Multicomponent Reactions; A Combined Cytotoxic Analysis and Computational Exploration

Multicomponent reactions involving zwitterion generated from dimethyl acetylenedicarboxylate, aryl sulfonamide, and isocyanide to generate sulfonamide-conjugated ketenimines is reported. The synthetic strategy adopted is highly atom economical and stereoselective. Ketenimine sulfonamide analogues are key intermediates for further synthetic conversions to generate a combinatorial library of compounds. Furthermore, sulfonamide compounds are known to possess a broad spectrum of biological applications. All the novel molecules synthesized exhibit the potential to target the nonhomologous DNA end-joining (NHEJ) pathway with cytotoxic ability. Computational studies compliment the in vitro biological assays of the 8 small-molecule inhibitors. DNA double-strand breaks (DSBs) are considered as the most lethal among different DNA damages. NHEJ repairs about 70% of the DSBs generated in cells within mammals. The DNA-dependent protein kinase catalytic subunit is one of the PI3 kinases associated with NHEJ. Compounds DK01-DK08 were investigated for their ability to induce cancer cell death by treating with two leukemic cell lines where NHEJ is high. Results showed that bromoaryl (DK04)- and nitroaryl (DK05)-conjugated molecules showed excellent biological activity, having IC50 values of ∼2 μM in Nalm6 cell lines.

Aptamers: Features, Synthesis and Applications

Aptamers have become a topic of interest among the researchers and scientists since they not only possess all of the benefits of antibodies but also possess special qualities including heat stability, low cost, and limitless uses⋅ Here we give a review about the features, applications, and challenges of aptamers and also how they are beneficial over the antibodies for biomedical applications. Their unique features make aptamers a prominent tool in therapeutics, diagnostics, biosensors and targeted drug delivery. In conclusion, aptamers represent exciting materials for a variety of applications and can be modified to improve their properties and to extend their applications in biomedical field.

P14.69 Evaluation of electric field intensity delivered by Tumor-Treating Fields therapy to PET-defined metabolic volumes in recurrent glioblastomas

BACKGROUND

Tumor-Treating Fields (TTFields) therapy is a clinical treatment option for patients with newly-diagnosed and recurrent glioblastomas. Electric field intensities (EFIs) delivered to the tumor mass may affect treatment responses. In this study, we used the patients’ neuroimaging data to create realistic head models and evaluate: (i) the magnitude of EFIs delivered to the tumor mass; (ii) factors affecting the EFI values; and (iii) factors affecting treatment responses as assessed by amino acid PET.

MATERIAL AND METHODS

Fourteen recurrent glioblastomas in 9 patients were evaluated with α-[11C]-methyl-L-tryptophan (AMT)-PET before and up to 3 months after TTFields therapy (mean follow-up: 2.3 months). Individual MRI and CT scans were used to create patient-specific realistic head models and simulate TTFields delivery to the tumors. For each direction of treatment (antero-posterior, left-right), two 9-disk transducer arrays were simulated using disks placed according to the patients’ NovoTAL System™ based treatment plan. To generate TTFields, an alternating voltage difference (200V peak-to-peak, 200 kHz) was imposed on the outer surfaces of the disks. The simulations were performed using the Sim4Life V3.0 (ZMT-Zurich) quasi-electrostatic solver. The field intensities were normalized to simulate 2A peak-to-peak current supplied by the device. 3D EFI maps were created and fused with the pre- and post-TTFields PET images to measure EFIs delivered to the PET-defined metabolic tumor volume. Interval changes of static AMT uptake and kinetic PET variables were also evaluated.

RESULTS

The mean EFI delivered to the tumors varied between 1.34–2.43 V/cm (mean: 1.86 V/cm). Fronto-parietal tumors received higher mean EFI than temporal lobe tumors (p=0.05). Most tumors showed decreasing (n=9) or stable (n=4) AMT uptake on follow-up PET imaging after TTFields therapy. Higher EFIs delivered to the tumors (r=-0.56, p=0.04) and concomitant bevacizumab treatment (n=7, p=0.01) were associated with a greater PET response. On tracer kinetic analysis, the AMT uptake responses correlated with transport rate changes (p=0.04).

CONCLUSION

TTFields treatment of recurrent glioblastomas delivers variable EFIs to the metabolic tumor volume. Treatment responses on PET are driven by decreased amino acid transport rates, whose magnitude is associated with higher EFIs delivered to the tumor mass and also with concomitant antiangiogenic treatment in those with combined therapy. (The cost of the PET scans was supported by a grant from NovoCure Ltd., Haifa, Israel)

P14.57 Association of tryptophan metabolism and depression in patients with primary brain tumors

BACKGROUND

Patients with brain tumor have an increased risk for depressive disorder, whose underlying pathomechanism may involve dysregulated tryptophan/kynurenine metabolism. In this study, we analyzed the relation of depression to cerebral and systemic tryptophan metabolism in patients with primary brain tumors.

MATERIAL AND METHODS

Thirty-four patients with newly-diagnosed (n=19) or recurrent (n=15) primary brain tumors (25 gliomas, 8 meningiomas, 1 dysembryoplastic neuroepithelial tumor) underwent pre-treatment alpha-[11C]methyl-L-tryptophan (AMT)-PET and completed the Beck Depression Inventory-II (BDI-II) questionnaire. MRI and AMT-PET images were co-registered, and AMT K values (estimate of unidirectional tryptophan uptake, related to tryptophan metabolism) were measured in contralateral non-tumoral cortical and subcortical regions and correlated with BDI-II total and subscale (cognitive, affective, and somatic) scores. In a subset of 28 patients, plasma tryptophan metabolite levels were also measured and correlated with BDI-II scores.

RESULTS

In the whole group (n=34), 35% of the patients (n=12) had BDI-II scores indicating depression, while only a minority of them (n=5) were treated with selective serotonin reuptake inhibitors (SSRI). No difference was observed in AMT K values between gliomas vs. non-gliomas or between newly-diagnosed vs. recurrent tumors. Frontal cortical and thalamic AMT K values positively correlated with BDI-II total and somatic subscale scores (r=0.49, p=0.004 and r=0.53, p=0.001, respectively), and these correlations became stronger when patients with SSRI treatment were excluded. Levels of plasma tryptophan and its metabolites were not different between gliomas vs. non-gliomas, newly-diagnosed vs. recurrent tumor nor depressed vs. non-depressed patients. SSRI treatment showed no effect on plasma tryptophan metabolite levels. No correlation was found between depression and plasma tryptophan and its metabolite levels.

CONCLUSION

While plasma levels of tryptophan metabolites are not associated with depressive symptoms, higher tryptophan metabolism in the frontal cortex and thalamus, measured by PET, may serve as an imaging biomarker of brain tumor-associated depression and supports the role of dysregulated tryptophan/kynurenine metabolism in this condition.

P14.37 Depression in patients with primary brain tumors: Relation to clinical variables and tumor characteristics

BACKGROUND

Patients with brain tumor have an increased risk for depressive disorder, however, the association between depression and clinical or tumor-related variables remains mostly unclear. In this study, we analyzed the relation of depression to several clinical and tumor-related characteristics in patients with primary brain tumors.

MATERIAL AND METHODS

Sixty patients with newly-diagnosed (n=34) or recurrent (n=26) primary brain tumors (50 gliomas, 10 meningiomas) underwent testing with the Beck Depression Inventory-II (BDI-II). Relation of BDI-II scores to clinical and tumor-related characteristics, including age, Karnofsky Performance Status (KPS) scores, presence of antiepileptic, antidepressant, or steroid treatment, as well as tumor grade, lateralization, and lobar localization, were analyzed. In a subset of recurrent malignant glioma patients, the prognostic value of BDI-II scores on overall survival was also analyzed.

RESULTS

The mean total BDI-II score was 10±8 (range: 0–37); while 27% of patients (n=16) had BDI-II scores indicating at least mild depressive disorder (≥13), only a portion of them (17%) was on antidepressant treatment. No BDI-II difference was found between gliomas vs. meningiomas or newly-diagnosed vs. recurrent tumors; also, no association was found with any tumor-related characteristics. Antiepileptic or steroid therapy had no association with BDI-II scores, while higher BDI-II scores were observed in patients with ongoing antidepressant therapy (15±10 vs. 8±7, p=0.017). Higher BDI-II total and somatic subscale scores correlated with lower KPS scores (r=-0.32, p=0.014 and r=-0.31, p=0.017, respectively). In recurrent malignant glioma patients (n=18), higher depression scores were associated with shorter survival (hazard ratio: 3.7; 95% confidence interval: 1.0–13.6; p=0.048).

CONCLUSION

Depression affected more than ¼ of patients with primary brain tumors in this single-center cohort and was independent from most clinical and tumor-related characteristics, except KPS scores. Although most of these patients have mild depression that is often overlooked without targeted screening, higher BDI-II scores may predict shorter overall survival in recurrent malignant glioma patients. These data reinforce the importance of early recognition and treatment of depressive symptoms in patients with primary brain tumors.

P11.35 Fluorine-18-labeled PET radiotracers for imaging tryptophan uptake and metabolism in brain tumors

BACKGROUND

Abnormal metabolism of tryptophan via the serotonin and kynurenine pathways plays a key role in multiple disease processes including cancer. Upregulation of key enzymes of the kynurenine pathway (such as indoleamine 2,3-dioxygenase [IDO] and tryptophan 2,3-dioxygenase [TDO]) plays an important role in immune resistance in human brain tumors. IDO inhibitors have recently entered in human clinical trials, and their use can benefit from molecular imaging evaluating IDO activity. Imaging tryptophan uptake and metabolism in vivo can be achieved with tryptophan derivative PET radiotracers. Human studies with such tracers showed promise but have been confined to carbon-11-labeled compounds (such as alpha-[11C]methyl-L-tryptophan). Preclinical development of fluorine-18-labeled tryptophan-based radiotracers has surged only in recent years. We performed a systematic review of studies reporting on such tracers and summarized their biological characteristics and their potential for imaging key enzymes of the kynurenine pathway.

MATERIAL AND METHODS

A PubMed search using the key words “tryptophan” and “PET”/”positron emission tomography” was performed. English language original articles including data on the preparation and/or radiochemical or biological characteristics of fluorine-18-labeled tryptophan derivative radiotracers have been reviewed.

RESULTS

Nineteen original papers identified by the search included data on 15 unique fluorine-18-labeled tryptophan-derived radiotracers. Automated synthesis was reported for 1-(2-[18F]fluoroethyl)-L-tryptophan, the most extensively evaluated tracer among the 15. Biodistribution studies showed high uptake in the pancreas, and the L-type amino acid transporter was the dominant transport mechanism for most of the reported radiotracers. Multiple tracers showed accumulation in various tumor cell lines, including glioma cell lines, in vitro and in xenografts in vivo, with favorable tumor-to-background uptake ratios in comparison to clinically used fluorine-18-labeled radiotracers (such as glucose and non-tryptophan amino acid analogs). Five of the 15 tracers showed promise for imaging IDO activity, including a fluorine-18-labeled analog of alpha-[11C]methyl-L-tryptophan. Two of the 15 radiotracers were metabolized by TDO but showed rapid defluorination in vivo.

CONCLUSION

Most fluorine-18-labeled tryptophan derivative PET tracers share common transport mechanisms and biodistribution characteristics. Several of these radiotracers show promise for imaging IDO activity in vivo, and, therefore, could be leading candidates for testing and validation toward human tumor PET imaging applications.

Autocyclized and oxidized forms of SCR7 induce cancer cell death by inhibiting nonhomologous DNA end joining in a Ligase IV dependent manner

Nonhomologous DNA end joining (NHEJ) is the major DNA double-strand break (DSB) repair pathway in mammals. Previously, we have described a small molecule inhibitor, SCR7, which can inhibit NHEJ in a Ligase IV-dependent manner. Administration of SCR7 within the cells resulted in the accumulation of DNA breaks, cell death, and inhibition of tumor growth in mice. In the present study, we report that parental SCR7, which is unstable, can be autocyclized into a stable form. Both parental SCR7 and cyclized SCR7 possess the same molecular weight (334.09) and molecular formula (C₁₈ H₁₄ N₄ OS), whereas its oxidized form, SCR7-pyrazine, possesses a different molecular formula (C₁₈ H₁₂ N₄ OS), molecular weight (332.07), and structure. While cyclized form of SCR7 showed robust inhibition of NHEJ in vitro, both forms exhibited efficient cytotoxicity. Cyclized and oxidized forms of SCR7 inhibited DNA end joining catalyzed by Ligase IV, whereas their impact was minimal on Ligase III, Ligase I, and T4 DNA Ligase-mediated joining. Importantly, both forms inhibited V(D)J recombination, although the effect was more pronounced for SCR7-cyclized. Both forms blocked NHEJ in a Ligase IV-dependent manner leading to the accumulation of DSBs within the cells. Although cytotoxicity due to SCR7-cyclized was Ligase IV specific, the pyrazine form exhibited nonspecific cytotoxicity at higher concentrations in Ligase IV-null cells. Finally, we demonstrate that both forms can potentiate the effect of radiation. Thus, we report that cyclized and oxidized forms of SCR7 can inhibit NHEJ in a Ligase IV-dependent manner, although SCR7-pyrazine is less specific to Ligase IV inside the cell.

[Treatment of coronary three-vessel disease in patients above 75 years]

BACKGROUND

Chronic ischemic heart disease take the first place in cause of death in Germany. The proportion of patients aged 75 years or older amounts more than 80 %. Due to their growing part of population the medical care of older patients becomes increasingly important. In this investigation patients aged ≥ 75 years with coronary three-vessel disease were characterized and various treatment strategies were compared.

PATIENTS AND METHODS

This analysis was retrospective. The data of patients aged 75 years or older with three-vessel disease diagnosed by coronary angiography at the Klinikum Lippe Detmold between 2005 and 2007 were collected. Depending on the received therapy they were parted in three groups: optimal drug therapy (OMT), interventional - (PCI) and surgical revascularization (CABG). Patient characteristics as well as survival- and MACCE-rates during follow up were ascertained. Subgroup analyzes were performed for acute coronary syndrom (ACS) and stable coronary artery disease( CAD).

RESULTS

The data of 434 patients with an average age of 79 years were documented. 139 (32.0 %) were assigned to the OMT- 189 (43.6 %) to the PCI- and 106 (24.4 %) to the CABG-group. Overall there was no significant difference between the three groups regarding mortality. In the subgroup of patients wit ACS (n = 180) mortality significantly increased in the OMT-group compared to the two invasive therapies (PCI (p = 0.029), CABG (p = 0.045)). The subgroup of patients with stable CAD showed no significant differences in mortality between the three types of therapy.

CONCLUSIONS

Older patients benefit from an interventional or surgical revascularization in the context of ACS. In contrast, in elderly with stable CAD optimal medical therapy provides a reasonable alternative to invasive therapy without increase in mortality.

Pluronic copolymer encapsulated SCR7 as a potential anticancer agent

Nonhomologous end joining (NHEJ) of DNA double strand breaks (DSBs) inside cells can be selectively inhibited by 5,6-bis-(benzylideneamino)-2-mercaptopyrimidin-4-ol (SCR7) which possesses anticancer properties. The hydrophobicity of SCR7 decreases its bioavailability which is a major setback in the utilization of this compound as a therapeutic agent. In order to circumvent the drawback of SCR7, we prepared a polymer encapsulated form of SCR7. The physical interaction of SCR7 and Pluronic® copolymer is evident from different analytical techniques. The in vitro cytotoxicity of the drug formulations is established using the MTT assay.

Enhanced efficacy of pluronic copolymer micelle encapsulated SCR7 against cancer cell proliferation

5,6-Bis(benzylideneamino)-2-mercaptopyrimidin-4-ol (SCR7) is a new anti cancer molecule having capability to selectively inhibit non-homologous end joining (NHEJ), one of the DNA double strand break (DSB) repair pathways inside the cells. In spite of the promising potential as an anticancer agent, hydrophobicity of SCR7 decreases its bioavailability. Herein the entrapment of SCR7 in Pluronic copolymer is reported. The size of the aggregates was determined by transmission electron microscopy (TEM) and dynamic light scattering (DLS) which yields an average diameter of 23 nm. SCR7 encapsulated micelles (ES) were also characterized by small-angle neutron scattering (SANS). Evaluation of its biological properties by using a variety of techniques, including Trypan blue, MTT and Live-dead cell assays, reveal that encapsulated SCR7 can induce cytotoxicity in cancer cell lines, being more effective in breast cancer cell line. Encapsulated SCR7 treatment resulted in accumulation of DNA breaks within the cells, resulting in cell cycle arrest at G1 phase and activation of apoptosis. More importantly, we found ≈ 5 fold increase in cell death, when encapsulated SCR7 was used in comparison with SCR7 alone.

Synthesis of truncated analogues for studying the process of glycosyl phosphatidylinositol modification

Many eukaryotic proteins are modified with a glycosylphosphatidylinositol (GPI) anchor at their C-termini. This post-translational modification causes these proteins to be noncovalently tethered to the plasma membrane. The synthesis of truncated GPI anchor analogues is reported; these compounds were designed for use as soluble substrates for GPI transamidase (GPI-T), the enzyme that appends the GPI anchor onto proteins.

Indeterminate rapid HIV-1 test results among antenatal and postnatal mothers

The sensitivity and specificity of rapid HIV-1 tests may be altered during pregnancy and postpartum. We conducted a study to determine the prevalence and correlates of false-positive Abbott Determine and false-negative Uni-Gold rapid HIV-1 test results among antenatal and postnatal mothers attending a primary care clinic in Nairobi, Kenya. Mothers were tested for HIV-1 using Abbott Determine and non-reactive results were considered HIV-1 antibody negative. Reactive samples by Determine were re-tested by Uni-Gold. Vironostika HIV-1 and Uni-FORM II Enzyme-linked immunosorbent assays were used to confirm samples that had positive Abbott Determine and negative Uni-Gold. Among 2311 women who accepted HIV-1 testing, 1238 (54%) were tested antenatally and 1073 (46%) were tested postnatally. Of tested women, 274 (12%) women were reactive by Abbott Determine and on retesting with Uni-Gold 30 (11%) had indeterminate results. The prevalence of indeterminate results was significantly higher in antenatal women than in postnatal women (2% versus 1%, P = 0.03). In conclusion, indeterminate rapid HIV-1 test results are more common in the antenatal period and appropriate safeguards to confirm HIV-1 infection status should be implemented in antenatal programmes.

Betaine-homocysteine methyltransferase is a developmentally regulated enzyme crystallin in rhesus monkey lens

We describe herein the characterization of a major 45-kDa protein from the soluble betaH-crystallin fraction of rhesus monkey (Macaca mulatta) lens. Based on partial peptide sequence, immunoreactivity, and enzymatic activity, this protein has been identified as betaine-homocysteine S-methyltransferase (BHMT: EC 2.1.1.5), an enzyme that catalyzes the methylation of homocysteine using either betaine or thetins as methyl donors. This protein was found to be expressed abundantly in the nuclear region of the monkey lens, reaching approximately 10% of the total nuclear protein, but was barely detectable in the epithelium and cortex regions of the lens. Because the nucleus represents the early embryonic and fetal stages of lens development, we infer that BHMT expression in the lens of the eye is developmentally regulated. By virtue of its high abundance, BHMT can be considered an enzyme crystallin (psi-crystallin). This is the first enzyme crystallin to be found in primate lenses.

Topical coal tar alone and in combination with oral methotrexate in management of psoriasis : a retrospective analysis

Thirty five patients admitted with psoriasis were analysed. 16 patients received 20% crude coal tar and 19 patients received 20% crude coal tar along with methotrexate in a weekly oral schedule (15mg/wk). After 4 weeks of therapy there was total clearence in 52.6% of the patients with combination therapy, whereas only 12.5% of the patients with conventional therapy achieved this.

Existence for large times of finite amplitude elastic waves arising from small disturbances

This paper deals with strict solutions u i ( t, x 1 , x 2 , x 3 ) of a system of quasi-linear equations [Formula: see text] with u′ = ([unk] x i u k ), and i, k, r, s ranging over 1, 2, 3. For given initial conditions u i = ε f i ( x 1 , x 2 , x 3 ), [unk] t u i = ε g ( x 1 , x 2 , x 3 ) for t = 0 the life-span T (ε) is the supremum of all t > 0 to which the u i can be extended as strict solutions for all x . It is shown that lim inf ε→0 ε log T (ε) > 0 for C ikrs , f i , g i [unk] C 0 ∞ , and C ikrs = C rsik , C ikrs (0) = 0.

Lower bounds for the life-span of solutions of nonlinear wave equations in three dimensions

The paper deals with strict solutions u(x,t) = u(x(1),x(2),x(3),t) of an equation [Formula: see text] where Du is the set of four first derivatives of u. For given initial values u(x,0) = epsilonF(x), u(t)(x,0) = epsilonG(x), the life span T(epsilon) is defined as the supremum of all t to which the local solution can be extended for all x. Blowup in finite time corresponds to T(epsilon) < infinity. Examples show that this can occur for arbitrarily small epsilon. On the other hand, T(epsilon) must at least be very large for small epsilon. By assuming that a(ik),F,G [unk] C(infinity), that a(ik)(0) = 0, and that F,G have compact support, it is shown that [Formula: see text] for every N. This result had been established previously only for N < 4.

[Elimination of pain by percutaneous thermorhizolysis in patients with inoperable bronchial carcinoma (author's transl)]

The percutaneous thermorhizolysis is a relatively simple technique for interrupting root function in the paravertebral space. Pain-conducting fibers can be selectively inactivated by a thermal probe heated to controlled temperatures. In a series of 25 cases with terminal cancer pain syndrome a good to very good relief of pain was obtained in 18 cases. In 4 cases the pain relief was partial. Only in 3 cases the treatment was completely ineffective. The procedure can be applied to patients who are debilitated due to carcinoma or old age and can be repeated if necessary.

Nonexistence of global solutions of squareu = F(u) and of squarev = F'(v)v in three space dimensions

The symbol square denotes the operator partial differential(2)/ partial differential(2) - Delta in three space dimensions, and F denotes a function with F(0) = F'(0) = 0, inf F'' > 0. It is shown that u(x,t) identical with 0, if squareu = F(u(tt)) for xin R(3), t >/= 0, provided u,u(t),u(tt) for t = 0 have compact support. Similarly v(x,t) identical with 0 if squarev = F'(v(t))v(tt) for x in R(3), t >/=0, provided v,v(t) for t = 0 have compact support and satisfy integral[v(t) - F(v(t))]dx >/= 0. This shows that the global existence theorem proved by S. L. Klainerman [(1980) Commun. Pure Appl. Math. 33, in press] in more than five space dimensions is not valid for three dimensions. The theorems also imply instability at rest of certain hyperelastic materials.

Distribution and metabolic fate of adenosine nucleotides in the membrane of storage vesicles from bovine adrenal medulla

The reactions of adenosine 14C-and gamma 32P-labelled ATP with isolated membranes from catecholamine storage vesicles of the bovine adrenal medulla were studied. In presence of Mg2+ about twice as much of 32P-radioactivity combined with the membrane as 14C-adenosine compounds at 31 degrees C and also at 0 degrees C, while in the absence of Mg2+ the amounts of 14C and 32P incorporated were similar for both substances. Autoradiography of the SDS-polyacrylamide gel after electrophoresis of the 32P-ATP-treated membrane protein showed two distinct zones corresponding to protein bands. Sonication released twice as much 32P-ATP as 14C-ATP from the space within the membrane particles indicating that at least half of the ATP present in space did not contain its original terminal phosphate group. About 40--45% of the 32P-radioactivity was incorporated in the membrane lipids, whereas only small amounts of 14C-radioactivity were extracted with lipids. About 1/3 of the incorporated 14C-radioactivity was not extractable with acids. The same amount remained in the 32P-ATP treated preparation acid-stably bound after extraction of the lipids and hus must be firmly bound ATP. When the reaction of the membrane preparation with labelled ATP was performed at 0 degrees C the fractions of the acid-stably bound 32P- and 14C-radioactivity increased. About 1 nmole/mg of protein (10--15%) of the bound 32P-radioactivity was exchangeable against unlabelled ATP, while only a very small fraction (less than 0.5 nmol/mg protein) of the 14C-radioactivity was exchanged against unlabelled ATP. Preincubation of the membrane particles with ATP-Mg2+ at 0 degrees C induced 30% inhibition of the ATPase activity and abolition of the net uptake of catecholamines. Different Km values obtained from initial velocity studies of ATPase activity and the overall-incorporation of 32P-radioactivity indicated that a direct correlation between these processes did not exist. Different strong inhibitory effects exerted by ADP on the ATPase activity and net uptake of catecholamine at the one hand and the overall 32P-and 14C-incorporation at the other hand supported that view. It is concluded that small fractions of the observed 32P-and 14C-incorporation can be involved in the ATP hydrolyzing reaction.

Epidemic hepatitis B caused by commercial human immunoglobulin

An epidemic of acute hepatitis B followed the administration of human immunoglobulin to members of the staff of a mission hospital in India and their families. Jaundice developed in 123 (38%) of 325 persons inoculated. Hepatitis-B surface antigen was detected in three of the batches of immunoglobulin which were available for testing.

Blow-up of solutions of nonlinear wave equations in three space dimensions

Solutions u(x, t) of the inequality squareu >/= A|u|(p) for x epsilon R(3), t >/= 0 are considered, where square is the d'Alembertian, and A,p are constants with A > 0, 1 < p < 1 + radical2. It is shown that the support of u is compact and contained in the cone 0 </= t </= t(0) -|x - x(0)|, if the "initial data" u(x, 0), u(t)(x, 0) have their support in the ball|x - x(0)| </= t(0). In particular, "global" solutions of squareu = A|u|(p) with initial data of compact support vanish identically. On the other hand, for A > 0, p > 1 + radical2, global solutions of squareu = A|u|(p) exist, if the initial data are of compact support and "sufficiently" small.

Restrictions on the coefficients of hyperbolic systems of partial differential equations

THE PAPER DEALS WITH HYPERBOLIC HOMOGENEOUS SYSTEMS [FORMULA: see text] of partial differential equations with constant coefficients for an N-vector u(t,x(1),...,x(n)). Here, P is a matrix form of order N and degree m. In the scalar case (N = 1), every hyperbolic P is limit of strictly hyperbolic ones. This does not hold for systems as is shown here for the special case N = n = 3, m = 2. Assuming P(1,0,...,0) to be the unit matrix, we represent P by a point in R(81). The hyperbolic P form a closed set H in R(81), the strictly hyperbolic ones an open subset H(s) of H. An example is given for a P in H which is not in the closure of H(s). Moreover, it is shown that near that P the set H coincides with an algebraic manifold of codimension 4.

Immune complex glomerulonephritis associated with Klebsiella pneumoniae infection

The kidneys of three patients who died of pneumonia due to Klebsiella pneumoniae were studied at autopsy by light and immunofluoerescent microscopy. One had no clinical evidence of renal disease; two had only microscopic hematuria and mild proteinuria. Light microscopy revealed focal proliferative glomerulonephritis in all three cases. Also in all three, immunofluorescent microscopy revealed a granular deposition of capsular polysaccharide antigens of Klebsiella pneumoniae in association with immunoglobulins and complement components in the mesangium and along the glomerular basement membrane. Furthermore, the glomerular bound immunoglobulins were eluted and demonstrated to contain antibodies specific to a capsular polysaccharide antigen of Klebsiella pneumoniae isolated from each patient. These findings may illustrate that the capsular polysaccharides of Klebsiella pneumoniae are antigenic, and that the immune complex deposition in the kidney during infection with this agent can be associated with renal morphological changes. Whether or not clinical evidence of nephritis occurs may depend on the characteristics of the infection and the host factors.

Delayed singularity formation for solutions of nonlinear partial differential equations in higher dimensions

Strict solutions u of genuinely nonlinear homogeneous hyperbolic equations in two independent variables with initial data f(x) of compact support become singular after a time interval of order parallelf parallel(-1). In higher dimensions solutions initially of compact support are likely to have life expectancies of orders parallelf parallel(-2+epsilon) at least. This is proved for the special case of solutions u(x(1),..., x(n), t) of a second order equation u(tt) = Sigma(i,j)a(ij)u(xixj), where n >/= 3 and where the coefficients a(ij) are C(infinity)-functions in the first derivatives of u, forming a symmetric positive definite matrix.

[Pendular and rotatory vestibular habituation]

The present investigations demonstrate in animals (rabbits) the existence of a habituation to the vestibular pendular stimulation comparable to the rotatory habituation by constant angular acceleration. There is no mutual transfer, however, between the two habituations. This confirms that the two modes of stimulation are not equivalent. All the tests have been made by ENG recording in total darkness.