Physiotherapy in Head, Neck, Lung and Breast Cancer Survivors: A Systematic Review

BACKGROUND

Cancer is a medical condition where some cells of the body reproduce uncontrollably and metastasize to other parts of the body. This study attempts to review the effect of physiotherapy application on head and neck, lung and breast cancer survivors on important clinical outcomes such as pain, strength, fatigability, coordination, balance, activities of daily living (ADLs), psychosocial aspects, cognitive aspects, and quality of life (QoL) Methods: A systematic review was conducted following PRISMA guidelines. Scientific articles were retrieved from electronic databases including Cochrane, Medline, EBSCO, Science Direct, Springer and Web of Science. Studies using only experimental design measuring the effectiveness of physiotherapy methods in head and neck, lung and breast cancer patients were selected for the review. Articles from 2012 till date were selected to find a piece of evidence for the latest physiotherapy practice in the last decade.

RESULTS

19 articles out of 9343 records were selected (Head & Neck HN = 3, Lung LU = 5, Breast BR = 11) which demonstrated that there was a significant effect of various physiotherapeutic techniques on the selected outcomes among patients with head and neck, lung and breast cancer.

CONCLUSION

In this review study, we conclude that head and neck cancer patients can benefit from physiotherapy exercises and muscle awareness. However, more evidence is needed to prescribe a specific exercise regimen. It was found that a combination of fitness training along with aerobic training has the maximum gain in advanced lung cancer patients. For breast cancer patients, combined aerobic and resistance training along with stretching and relaxation is the current suggested treatment.

KEY WORDS

"Upper Body Cancer", "Physiotherapy", "head and neck cancer", "lung cancer", and "breast cancer".

The Need for Early Screening of Diabetic Peripheral Neuropathy and Diabetic Foot in MENA Region: A Review

BACKGROUND

Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes mellitus. Among all complications of DPN, diabetic foot (DF) can cause a myriad of symptoms and impact the quality of life. This study aimed to review the prevalence of DPN and DF in the Middle East and North Africa (MENA) region based on the publications available. This systematic review can be a cornerstone for further research and it summarizes the literature published on the prevalence of DPN and DF for the last two decades in the MENA region.

METHODOLOGY

The databases, PubMed, ResearchGate, Scopus, Web of Science, Science Direct, CINAHL, and Cochrane were searched using relevant keywords for the study. Full articles in English since 2000, including keywords "Prevalence", "Diabetic peripheral neuropathy", "Diabetic foot", and "MENA region" were reviewed in two phases. All authors screened the titles and abstracts of the articles individually, which was followed by a screening of full texts. A consensus was made among all the authors for the final selection of the articles based on the eligibility criteria.

RESULTS

Ten selected articles on the prevalence of DPN were reviewed in the first phase of the study, which reported varying prevalence rates among the different countries of the MENA region ranging from 9% to 61%. In the second phase, only two articles on DF prevalence were shortlisted. They reported the prevalence of DF as 4.6% and 18.1% in Jordan and Sudan, respectively.

CONCLUSION

The prevalence of DPN in the MENA region is varied within a short period of time and the reported prevalence of DF is limited. This study projects a strong need of establishing early screening strategies for DPN and DF to prevent further complications and decrease healthcare burden.

Determinants of hand function in children and adolescent with Down Syndrome-A scoping review

BACKGROUND

Down Syndrome (DS) is a genetic condition. Physical characteristics like short stature, hypotonia, small, and thick hands result in decreased grip and pinch strength and quality of fine motor tasks.

PURPOSE

The purpose of this review is to summarize the evidence of upper extremity physical characteristics and its influence on hand function in DS population.

STUDY DESIGN

A scoping review.

METHODOLOGY

A comprehensive electronic literature search was conducted through PubMed, CINAHL, Cochrane Library. The search was limited to articles written in English and published between 2010 to 2021. Additionally, books were referred for a better understanding of the hand function in DS. The Preferred Reporting Items for Systematic Review and Meta-Analysis extension for scoping reviews (PRISMA-ScR) was adopted to develop the protocol.

RESULTS

Following a detailed review of 28 articles meeting the inclusion criteria, fetuses with a diagnosis of DS are reported to have shortening of humerus on sonographic markers wherein 9% of fetuses had below 5th percentile shortening. Additionally, literature reports that during reaching there was increased trunk rotation (effect size = 0.88). DS population had 60% less grip strength, 33% less palmar pinch strength ,20% less key pinch strength and poor manual dexterity (CI = 4.5-5.5).

CONCLUSION

Findings of this review concludes that physical characteristics of the upper extremity have an influence on hand function performance in children and adolescents with DS.However, only arm length and hand span have been quantified and correlated with grip strength. Further work must focus on correlation of upper extremity anthropometry and overall hand function in children and adolscents with DS.

Dexteria app. therapy versus conventional hand therapy in stroke

Purpose

Hand impairment post-stroke is a very common and important rehabilitation goal for functional independence. Advanced therapy options such as an app. therapy provides repetitive training, which may be beneficial for improving fine motor function. This study aims to evaluate the effect of app-based therapy compared to conventional hand therapy in improving dexterity in individuals with stroke.

Methodology

In total, 39 individuals within the first year of stroke with Brunnstrom stage of hand recovery IV to VI were randomly divided into three groups. All three groups received 60 min of therapy for 21 sessions over a period of 30 days. Group A received conventional hand therapy; Group B received app. therapy, while Group C received conventional therapy along with the app. therapy. All participants were assessed on the Nine-Hole Peg Test and Jebsen–Taylor Hand Function Test at the beginning and after completion of 21 sessions of intervention. Kruskal–Wallis (H) test and Wilcoxon test were used for statistical analysis.

Results

All three groups improved on hand function post-treatment. However, Group C demonstrated significant improvement with 16%–58% increase in hand function performance on outcome measures (p < 0.05).

Findings

Findings of the present study demonstrate improvement in dexterity with the app. therapy and combination therapy, in comparison to conventional therapy alone in individuals with stroke.

Originality

This experimental study focuses the first time on a structured protocol using an enabling technology adjunct to conventional physical therapy to improve hand function in individuals with stroke, which opens up the further scope in Neurorehabilitation.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0144/

Exploring spinal muscular atrophy and its impact on functional status: Indian scenario

The present study aimed to find out the effect of disease-related impairments on functional status in individuals with spinal muscular atrophy and identify perceived barriers to undergo physiotherapy. The cross-sectional observational study was conducted on 90 participants from January to March 2018 using validated patient-reported questionnaire via electronic mail, along with Fatigue Severity Scale and ACTIVLIM. Results revealed that difficulty in sitting was due to scoliosis (36%) and muscle weakness (23%), the latter also contributing toward difficulty in standing and walking (59%). Inverse relationship exists between ACTIVLIM measures and fatigue severity scores (r = -0.338, P < 0.05), body mass index (r = -0.225, P < 0.05), age (r = -0.258, P < 0.05), and duration of illness (r = -0.257, P < 0.05). Economic constraints (27%), difficulty in traveling (17%), and lack of family support and mobility (14%) are perceived barriers to undergo physiotherapy. Functional impairments and identified barriers must be addressed as part of rehabilitation.

Enteric fever in an HIV/AIDS patient: Atypical manifestations

Bloodstream infections with Salmonella typhi, is uncommon in human immunodeficiency virus (HIV)-infected persons. The symptoms in such patients are often non-specific and have a rather insidious onset and progression. We report a patient with sepsis and lower limb gangrene due to Salmonella typhi infection in an HIV-infected patient.

Gastric bypass surgery, but not caloric restriction, decreases dipeptidyl peptidase-4 activity in obese patients with type 2 diabetes

The mechanism by which incretins and their effect on insulin secretion increase markedly following gastric bypass (GBP) surgery is not fully elucidated. We hypothesized that a decrease in the activity of dipeptidyl peptidase-4 (DPP-4), the enzyme which inactivates incretins, may explain the rise in incretin levels post-GBP. Fasting plasma DPP-4 activity was measured after 10-kg equivalent weight loss by GBP (n = 16) or by caloric restriction (CR,n = 14) in obese patients with type 2 diabetes. DPP-4 activity decreased after GBP by 11.6% (p = 0.01), but not after CR. The increased peak glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) response to oral glucose after GBP did not correlate with DPP-4 activity. The decrease in fasting plasma DPP-4 activity after GBP occurred by a mechanism independent of weight loss and did not relate to change in incretin concentrations. Whether the change in DPP-4 activity contributes to improved diabetes control after GBP remains therefore to be determined.

Virtual vs. optical colonoscopy in symptomatic gastroenterology out-patients: the case for virtual imaging followed by targeted diagnostic or therapeutic colonoscopy

AIM

To compare virtual colonoscopy with optical colonoscopy findings in symptomatic patients.

BACKGROUND

Computer tomographic colonography is an alternative to optical colonoscopy. Studies have shown that two-dimensional computer tomographic colonography does not have sufficient sensitivity. Three-dimensional computerized tomographic virtual colonoscopy compares well with optical colonoscopy for colorectal neoplasia screening in asymptomatic individuals.

METHODS

One hundred patients aged 50 and older underwent same day virtual colonoscopy and optical colonoscopy. The endoscopists were unaware of the radiologist's report until the withdrawal phase of the endoscopy when segmental unblinding occurred. The virtual colonoscopy and optical colonoscopy findings were compared by using the unblinded optical colonoscopy as the reference standard.

RESULTS

Pancolonic endoluminal virtual colonoscopy was achieved in 99 patients. Optical colonoscopy caecal intubation occurred in 91 patients. Direct comparison was possible in 90 patients. Both techniques revealed the three cancers detected. Virtual colonoscopy revealed 11 polyps > or = 6 mm diameter in nine patients. Optical colonoscopy revealed 10 polyps > or = 6 mm diameter in nine patients with a further 15-mm polyp discovered after segmental unblinding.

CONCLUSION

In symptomatic patients, three-dimensional virtual colonoscopy is equivalent to optical colonoscopy for diagnosing colon cancer and clinically significant polyps. A case can be made for three-dimensional virtual colonoscopy as a primary modality followed if necessary by same day-targeted optical colonoscopy.

Drug resistance profile of human Mycobacterium avium complex strains from India

PURPOSE

To determine minimum inhibitory concentration (MIC) of various anti-tuberculosis drugs for Mycobacterium avium complex (MAC) strains isolated from clinical samples.

METHODS

Forty-nine human isolates of MAC were tested for susceptibility to nine chemotherapeutic agents. All isolates were from Indian patients suffering from chronic pulmonary mycobacteriosis. Drug susceptibility was performed both by agar dilution and MIC method. MIC values were analysed, both visually and by enzyme-linked immunosorbent assay reader.

RESULTS

More than 40% of the MAC isolates were sensitive to ciprofloxacine (48.98%), amikacin (46.94%) and roxithromycin (42.86%) by the MIC method. In contrast, the isolates showed high degree of resistance to the first line antituberculosis drugs: only 28.6% were sensitive to rifampicine, 22.85% to isoniazid and ethambutol each and 36.7% were sensitive to streptomycin. In addition, 22.85% of the strains were sensitive to clofazimine and 34.7% to kanamycin.

CONCLUSIONS

Results of the study confirm the suitability of the rapid broth micro dilution (MIC) method as a simple yet reliable method to assay for the drug susceptibility of nontuberculosis mycobacterium.

Muscarinic M2 and M1 receptors reduce GABA release by Ca2+ channel modulation through activation of PI3K/Ca2+ -independent and PLC/Ca2+ -dependent PKC

We measured pharmacologically isolated GABAergic currents from layer II/III neurons of the rat auditory cortex using patch-clamp recording. Activation of muscarinic receptors by muscarine (1 microM) or oxotremorine (10 microM) decreased the amplitude of electrically evoked inhibitory postsynaptic currents to about one third of their control value. Neither miniature nor exogenously evoked GABAergic currents were altered by the presence of muscarinic agonists, indicating that the effect was spike-dependent and not mediated postsynaptically. The presence of the N- or P/Q-type Ca(2+) channel blockers omega-conotoxin GVIA (1 microM) or omega-AgaTx TK (200 nM) greatly blocked the muscarinic effect, suggesting that Ca(2+)-channels were target of the muscarinic modulation. The presence of the muscarinic M(2) receptor (M(2)R) antagonists methoctramine (5 muM) or AF-DX 116 (1 microM) blocked most of the muscarinic evoked inhibitory postsynaptic current (eIPSC) reduction, indicating that M(2)Rs were responsible for the effect, whereas the remaining component of the depression displayed M(1)R-like sensitivity. Tissue preincubation with the specific blockers of phosphatidyl-inositol-3-kinase (PI(3)K) wortmannin (200 nM), LY294002 (1 microM), or with the Ca(2+)-dependent PKC inhibitor Gö 6976 (200 nM) greatly impaired the muscarinic decrease of the eIPSC amplitude, whereas the remaining component was sensitive to preincubation in the phospholipase C blocker U73122 (10 microM). We conclude that acetylcholine release enhances the excitability of the auditory cortex by decreasing the release of GABA by inhibiting axonal V-dependent Ca(2+) channels, mostly through activation of presynaptic M(2)Rs/PI(3)K/Ca(2+)-independent PKC pathway and-to a smaller extent-by the activation of M(1)/PLC/Ca(2+)-dependent PKC.

A nascent HIV type 1 epidemic among injecting drug users in Kabul, Afghanistan is dominated by complex AD recombinant strain, CRF35_AD

Injecting drug use (IDU), common in global centers of heroin production, confers significant risk for HIV-1 infection. Once introduced into IDU networks, an explosive rise in HIV-1 infection typically occurs, fueled principally by needle sharing. New HIV-1 epidemics in IDUs have occurred in Russia, China, Thailand, Spain, Iran, and in other countries, and some have spread into other risk groups in their respective countries. In Afghanistan, the introduction of HIV-1 into IDU networks has begun, but a recent report of 3% HIV-1 prevalence suggests that the epidemic is still at an early stage. Here we establish, by complete genome sequencing and phylogenetic analysis of four viral strains from Afghan IDUs, that all are the same complex recombinant strain, combining HIV-1 subtypes A and D and herein termed CRF35_AD. Published partial HIV-1 sequences from an HIV-1 epidemic among IDUs in Iran, already at 23.2% HIV-1 prevalence, are either CRF35_AD or a related recombinant. Voluntary HIV-1 screening and harm reduction programs in Afghanistan, applied now, could limit the spread of HIV-1, both in IDUs and in other social networks.

Prophage Finder: a prophage loci prediction tool for prokaryotic genome sequences

Prophage loci often remain under-annotated or even unrecognized in prokaryotic genome sequencing projects. A PHP application, Prophage Finder, has been developed and implemented to predict prophage loci, based upon clusters of phage-related gene products encoded within DNA sequences. This application provides results detailing several facets of these clusters to facilitate rapid prediction and analysis of prophage sequences. Prophage Finder was tested using previously annotated prokaryotic genomic sequences with manually curated prophage loci as benchmarks. Additional analyses from Prophage Finder searches of several draft prokaryotic genome sequences are available through the Web site (http://bioinformatics.uwp.edu/~phage/DOEResults.php) to illustrate the potential of this application.

Brazil nut effect and excluded volume attraction in vibrofluidized granular mixtures

A two dimensional bi-disperse vibrofluidized granular mixture is studied in the rapid flow regime, where particle interactions occur due to instantaneous collisions. Both experiments and simulations are carried out, and these show the existence of two phenomena which have been observed only in very dense granular flows or in equilibrium systems. The Brazil nut phenomenon, which involves the rise of larger particles in a granular mixture upon vibration, has been observed in dense systems due to the percolation of small particles though the interstitial spaces between the large particles, or due to convection rolls. In the present case, where neither effect is present, it is observed that the fluidization of the smaller particles by vibration results in an exponentially decaying density profile, at heights large compared to the particle diameter, and thereby a pressure field that decreases with height. The larger particles, suspended in this decaying pressure field, experience a larger pressure at the bottom and a smaller pressure on top, and they rise to a height where the net force caused by the decreasing pressure is balanced by the weight of the particle. An attractive force between the large particles, similar to the entropic attraction effect in mixtures of colloids and polymers, is also observed in this nonequilibrium system, because when the distance between the large particles is less than the small particle diameter, the pressure between the large particles is smaller than that on the outside. Analytical results are derived for each of these effects, and these are in agreement with the experimental and simulation results.

‘Nature-inspired’ drug–protein complexes as inhibitors of Aβ aggregation

Protein–protein interactions are a regulatory mechanism for a number of physiological and pathological cellular processes. Neurodegenerative diseases, such as AD (Alzheimer's disease), are associated with the accelerated production or delayed clearance of protein aggregates. Hence, inhibition of pathologic protein–protein interactions is a very attractive mechanism for drug development. This review focuses on a novel therapeutic strategy to inhibit the de novo formation of protein aggregates. Inspired by strategies used in Nature and optimized over millions of years of evolution, we have created a bifunctional molecule [SLF (synthetic ligand for FK506-binding protein)–CR (Congo Red)] that is able to block Aβ (amyloid β) aggregation by borrowing the surface and steric bulk of a cellular chaperone.

Drug-sensitivity profile of clinical Mycobacterium tuberculosis isolates--a retrospective study from a chest-disease institute in India

Multi-drug-resistant tuberculosis (MDR-TB) is a major public-health problem, because treatment is complicated and patients remain infectious for months or years, despite receiving the best available therapy. To gain better understanding of MDR-TB, a retrospective study was initiated to determine the level of drug resistance among patients in a chest-disease institute in India. Two hundred and sixty-three isolates from treatment-failure pulmonary tuberculosis patients (20-70 years) were studied. Drug-sensitivity testing was performed by the modified-proportion method. First- and second-line drugs, along with two quinolone drugs (ofloxacin and ciprofloxacin), were tested. Patients included in this study did not improve with therapy; however, 151 isolates (57.5 %) were susceptible to all four first-line antituberculosis drugs. This study reports low resistance to fluoroquinolones among the strains present in these patients.

Velocity distribution for a two-dimensional sheared granular flow

The velocity distribution for a two-dimensional collection of disks of number density n per unit area and radius a in a channel of width L is studied. The particle-particle collisions are considered to be inelastic with a coefficient of restitution e, while the particle-wall coefficients of restitution are inelastic with a tangential and normal coefficients of restitution, e(t) and e(n), respectively. The Knudsen number, which is the ratio of the channel width and the mean free path of the particles, is varied from Kn<<1 to Kn>>1. In the limit of high Knudsen number, the distribution function for the streamwise velocity is bimodal, as predicted by theory [J. Fluid Mech. 340, 3l9 (1997)]], and the scalings of the moments of the velocity distribution with the Knudsen number are in agreement with the theory. In the low Knudsen number limit, the distribution function for the streamwise velocity is a Gaussian if the coefficient of restitution is close to 1, but assumes the form of a "composite Gaussian" if the coefficient of restitution is not close to 1. The distribution function has a complex structure in the intermediate regime, where there are three maxima in the distribution function near the wall, while the distribution function is bimodal at the center. The granular temperature is accurately predicted by kinetic theory at the center of the channel, but there is dissipation at the wall due to inelastic particle-wall collisions, which results in a significant decrease in the temperature even when the coefficient of restitution is 0.9; this finding is in agreement with previous results with bumpy wall boundary conditions and with specular reflection conditions. The slip velocity at the wall has a power law dependence on the Knudsen number, and the exponent in this power law depends on the coefficients of restitution.

Disease progression markers during asymptomatic phase of HIV-1 infected children with unimpaired CD4+ cell values: evaluation of repeat CD4+ cell evaluation vs. other immunological parameters

The availability of a marker that could predict the course of disease progression in HIV-infected individuals would be of considerable relevance during the asymptomatic stage in order to undertake timely prophylactic measures. A prospective study was undertaken in a group of 42 children suffering from thalassemia major with HIV-1 infection to assess the status of immune parameters, such as peripheral CD4+ T lymphocyte (CD4+ cell) percentage, delayed type of hypersensitivity (DTH) response to recall antigens, detection rate and levels of p24 antigen, and levels of beta-2 microglobulin and cytokines in serum. All were assessed at an interval of 2 years during the asymptomatic period, (baseline and follow-up assessments) in relation to the development of AIDS defining illness within a follow-up period of 3 years. No difference could be observed in the mean CD4+ cell percentage at baseline between those who progressed subsequently to develop AIDS within the follow-up period (progressors) and those who did not (non-progressors). However, at the point of follow-up assessment the progressor group showed significantly lower CD4+ cell percentage compared to the non-progressor group (33 +/- 4.9 vs. 22 +/- 5.6; p < 0.05), although in the progressor group there was no correlation of the baseline and follow-up CD4+ cell percentage with the duration of the AIDS-free interval. However, in the progressor group there was a strong negative correlation between the rate of decline in CD4+ cell percentage and subsequent duration of the AIDS-free interval (r = -0.859). Analysis of additional immune parameters at baseline revealed that the progressor group, despite having CD4+ cell values comparable to non-progressors, showed impaired DTH response (number and total induration of positive responses being 2.0 +/- 1.23 and 6.2 +/- 1.4 in the former group vs. 3.2 +/- 0.76 and 12.6 +/- 3.80 in the later group; p < 0.05 for both the parameters), and elevated levels (mg/l) of serum beta-2 microglobulin (2.92 +/- 0.89 vs. 1.38 +/- 0.43; p < 0.05). The serum cytokine profile at baseline in the progressor group showed a T helper type-2 (Th2) dominant pattern, i.e. elevation of interleukin-4 (IL-4) and interleukin-10 (IL-10) levels with decreased levels of interleukin-2 (IL-2) and gamma interferon (gamma-IFN) compared to the non-progressor group that showed a T helper type-1 (Th1) dominant profile, i.e., elevation of IL-1 and gamma-IFN level with decreased levels of IL-4 and IL-10 (p < 0.05 for all four cytokines). The present study points out that rate of decline rather than single point of assessment of CD4+ cell values is a more reliable predictor for disease progression in HIV-1 infected children. In addition, parameters such as DTH response, serum levels of beta-2 microglobulin and serum cytokine profile, may provide valuable predictors of subsequent fall in CD4+ cell value.

Inhibition of the in-vitro growth of Mycobacterium tuberculosis by a phytosiderophore

Non-compliance by patients and poor clinical management due to the use of incorrect regimens are the main reasons for the development of drug resistance by mycobacterial strains. New strategies for the control of multi-drug-resistant mycobacterial strains have become a necessity for proper management of tuberculosis, which, according to the WHO report (1997), is estimated to remain among the top 10 mortality-causing diseases of the twenty-first century. One of the strategies is the use of iron-sequestering agents like siderophores as active therapeutic agents in the treatment of tuberculosis. This report describes for the first time the inhibition of the growth of Mycobacterium tuberculosis H37Ra in vitro by a phytosiderophore isolated from the root washings of Tephrosia purpurea. This finding may help in the establishment of a new drug regimen which will be more effective in the treatment of tuberculosis.

Role of cytokines in immune response to pulmonary tuberculosis

Immunopathogenesis of tuberculosis needs to be explored in search of a proper vaccine as well as for adjunctive immunotherapy particularly in patients with drug resistant tuberculosis. In tuberculosis, IFN-gamma, a product of T lymphocytes, contributes to protective immunity against M. tuberculosis by activating macrophages to a more effective elimination of these organisms. Interleukin-12 and interleukin-18 are macrophage products that favor the development of Th1 type of protective immune response. Production of these cytokines may not only facilitate granuloma formation and bacillary elimination but may also cause local tissue necrosis and systemic effects such as fever and wasting, due to the release of TNF-alpha into the circulation. The production of anti-inflammatory cytokines such as IL-10, TGF-beta and IL-4 in response to M. tuberculosis may down regulate the immune response and limit tissue injury by inhibiting excessive inflammatory response. These cytokines, if produced in excess, may result in failure to control infection resulting in widely disseminated tuberculosis. It is the balance between the inflammatory and protective immune response that determines the outcome of tuberculosis infection. In that context, increased IFN-y as against reduced TNF-alpha probably suggests a better outcome. Similarly, an effective vaccine has to stimulate a precise combination of T cells and cytokines needed for the many aspects of immune response and a potent immunotherapeutic agent may require to encompass the multiple parameters to be of therapeutic relevance.

Spatiotemporal dynamics near a supercritical Turing-Hopf bifurcation in a two-dimensional reaction-diffusion system

Pattern formation in semiconductor heterostructures is studied on the basis of a spatially two-dimensional model of reaction-diffusion type. In particular, we investigate the neighborhood of a codimension-two Turing-Hopf instability by analytical methods. Amplitude equations are derived which predict the absence of mixed modes but extended ranges of bistability between homogeneous oscillatory states and hexagonal Turing patterns. Our results are confirmed by numerical simulations. The features are not confined to a neighborhood of the bifurcation point so that the conclusions of the weakly nonlinear analysis explain the observations in large portions of the parameter space at least qualitatively

Acetoxy-4-methylcoumarins confer differential protection from aflatoxin B(1)-induced micronuclei and apoptosis in lung and bone marrow cells

The ability of various acetoxy derivatives of 4-methylcoumarins to inhibit the genotoxic changes due to aflatoxin B(1) (AFB(1)) is reported here. Several 4-methylcoumarins (test compounds), such as 7,8-diacetoxy-4-methylcoumarin (DAMC), monoacetoxy-4-methylcoumarin (MAC), 5-N-acetyl-6-acetoxy-4-methylcoumarin (NAMC) and 7,8-dihydroxy-4-methylcoumarin (DHMC) were separately administered intraperitoneally (i.p.) to male wistar rats followed by AFB(1) administration i.p. or intratracheally (i.t.) (2-8 mg/kg b.wt.) and another dose of the test compound. The animals were sacrificed 26h after AFB(1) administration. From animals receiving AFB(1) i.p., bone marrow (BM) cells were isolated and stained with Mayer's haematoxylin and eosin. Micronuclei (MN) in BM were scored by light microscopy. From animals receiving AFB(1) i.t., bronchoalveolar lavage (BAL) was obtained, lung cells (LG) were isolated and stained with fluorochrome 6-diamidino-2-phenylindole (DAPI) for the analysis of MN, apoptotic bodies (AP) and cell cycle variations. Rats were separately treated with the vehicle DMSO to serve as the proper control. AFB(1) caused significant dose-dependent induction of MN in BM as well as LG. AP were observed in LG of rats receiving AFB(1) and was found to correlate with MN induction. DAMC injection caused significant decrease in AP due to AFB(1) in LG and MN in both BM and LG. The effectiveness of MAC was approximately half that of DAMC, thereby indicating that number of acetoxy groups on the coumarin molecule determine the efficacy. The fact that NAMC had no effect either on MN or AP indicate that neither acetoxy group at C-6 nor the N-acetyl group at C-5 facilitate the transfer of acetyl group to P-450 required for inhibition of AFB(1)-epoxidation. DHMC, the deacetylated product of DAMC had no normalizing effect on the induction of MN and AP. These findings confirm our earlier hypothesis that DAMC-mediated acetylation of microsomal P-450 (catalysing epoxidation of AFB(1)) through the action of microsomal transacetylase is responsible for the protective action of DAMC. The relative number and position of acetoxy groups on the coumarin nucleus determine the specificity to the transacetylase necessary for the chemopreventive action.

A convergent triflate displacement approach to (alpha-monofluoroalkyl)phosphonates

[reaction: see text] Treatment of primary alkyl triflates or iodides with the potassium salt of diethyl (alpha-fluoro-alpha-phenylsulfonylmethyl)phosphonate yields (alpha-fluoro-alpha-phenylsulfonylalkyl)phosphonates. These can be cleanly desulfonated, in a matter of minutes, with Na(Hg) in MeOH/THF/NaH(2)PO(4). This two-step procedure complements previously reported triflate displacement approaches to alpha-nonfluorinated and alpha,alpha-difluorinated phosphonates.

Chemoprevention of benzene-induced bone marrow and pulmonary genotoxicity

Our earlier studies documented the ability of 7,8-diacetoxy-4-methylcoumarin (DAMC) to cause irreversible inhibition of cytochrome P-450 linked mixed function oxidases (MFO) mediated by membrane bound DAMC: protein transacetylase. Since P-450 catalyzed oxidation of benzene is crucial to its toxic effects, the action of DAMC and related analogues were considered promising in preventing the genotoxicity due to benzene. For this purpose rats were pretreated with various acetoxy-4-methylcoumarins (test compounds), which was followed by the administration of benzene either intratracheally (IT) or intraperitoneally (IP), and sacrificed 26 h after the injection of benzene. The incidence of micronuclei (MN) in bone marrow (BM) and lung (LG) were assessed by light and fluorescent microscopy, respectively. A dose-dependent induction of MN in BM and LG cells was observed in rats administered with benzene. A significant reduction in benzene-induced MN in BM and LG was observed as a result of DAMC administration to rats; a higher dose of DAMC resulted in greater inhibition of clastogenic action of benzene as revealed by MN incidence. 7,8-dihydroxy-4-methylcoumarin (DHMC), the deacetylated product of DAMC, demonstrated relatively lesser potency to inhibit the clastogenic action of benzene. This observation is consistent with the ability of DAMC to inhibit the formation of benzene oxide as well as to scavenge the oxygen radicals formed during the course of benzene metabolism. The fact that DHMC can only scavenge the oxygen radicals and is ineffective in inhibiting benzene oxidation in vivo explains the reduced capability of dihydroxy coumarin to prevent MN due to benzene. 7-Acetoxy-4-methylcoumarin (MAC) inhibits the MN due to benzene being roughly 50% of that produced by DAMC. DAMC is also effective in normalizing the cell cycle alterations produced by benzene in BM and LG. These observations further substantiate our hypothesis that the biological effects of acetoxy coumarins are mediated by the action of membrane bound transacetylase that catalyzes the acetylation of concerned proteins. Teratogenesis Carcinog. Mutagen. 21:181-187, 2001.

alpha-fluorinated phosphonates as substrate mimics for glucose 6-phosphate dehydrogenase: the CHF stereochemistry matters

Reported is a systematic study of the "fitness" (in terms of kcat/Km) of a series of phosphonate mimics of glucose 6-phosphate (G6P) as unnatural substrates for G6P dehydrogenase from Leuconostoc mesenteroides. The four G6P analogues (9, 10, 15a, and 15b) differ only in the degree of fluorination at the "bridging" phosphonate carbon. All have been synthesized from benzyl 6-O-trifluoromethanesulfonyl-2,3,4-tri-O-benzyl beta-D-glucopyranoside (6). The phosphonates with bridging CH2 (9) and CF2 (10) groups are cleanly obtained by direct displacements with the appropriate LiX2CP(O)(OEt)2 reagents (X = H, F) in 15 min at -78 degrees C. For the (alpha-monofluoro)alkylphosphonates (15a/b), homologation of 6 is achieved via lithiodithiane-mediated triflate displacement, followed by aldehyde unmasking [CaCO3, Hg(ClO4)2, H2O]. Addition of diethyl phosphite anion produces diastereomeric, (alpha-hydroxy)phosphonates 13a/b (1.4:1 ratio) which may be readily separated by chromatography. The stereochemistry of the minor diastereomer was established as 7(S) via X-ray crystallographic structure determination of its p-bromobenzoate derivative, 16b. Treatment of the major 7(R) diastereomer with DAST produces alpha-fluorinated phosphonate 14a, in modest yield, with inversion of configuration, as established, again, by X-ray crystallography. To our knowledge, this is first example of DAST-mediated fluorination of a (nonbenzylic, nonpropargylic) secondary (alpha-hydroxy)phosphonate and thus establishes the stereochemical course of this transformation. alpha-Deprotonation/kinetic quenching of 14a provides access to the 7(R)-epimer (14b). For all four protected phosphonates (7, 8, 14a, and 14b), diethyl phosphonate ester deprotection was carried out with TMSBr, followed by global hydrogenolytic debenzylation to produce the free phosphonates, as alpha/beta anomeric mixtures. Titrations of G6P itself and the free phosphonic acids provides second pKa values of 6.5 (1, bridging-O), 5.4 (10, bridging-CF2), 6.2 (14a, bridging-CHF), and 7.6 (9, bridging-CH2). Leuconostoc mesenteroides G6PDH-mediated oxidation and Lineweaver-Burk analysis yields normalized kcat/Km values of 0.043 (14b, bridging-7(R)-CHF), 0.11 (10, bridging-CF2), 0.23 (14b, bridging-CH2), and 0.46 (14a, bridging-7(S)-CHF) relative to G6P itself, largely reflecting differences in Km. The fact that kcat/Km increases by more than an order of magnitude in going from the 7(R)-alpha-monofluoroalkyl phosphonate (worst substrate) to the 7(S)-diastereomer (best substrate) is especially notable and is discussed in the context of the known phosphate binding pocket of this enzyme as revealed by X-ray crystallography (Adams, M. J. et al. Structure 1994, 2, 1073-1087).

Aflatoxin B1-induced micronuclei and cell cycle alterations in lung and bone marrow cells and their modulation by Piper argyrophyllum extract

Aflatoxin B, (AFB1) is a clastogen that causes cellular damage by covalent modification of nucleic acids. In this investigation, male rats were injected i.p. with AFB1 (8 mg/kg b.w.) in DMSO and the same dose of AFB1 was also administered intratracheally (i.t.) to the animals separately. The animals were killed after 26 h of the carcinogen treatment, femur bone was removed, and bone marrow cells were isolated and stained with Mayer's hematoxylin and eosin. Micronuclei (Mn) were scored by using light microscopy. Bronchoalveolar lavage (BAL) was prepared from rats administered AFB1 i.t. A part of BAL was fixed with 70% ethanol, stained with the fluorochrome DAPI, and analysed for cell cycle variations; the other part of the lavage was used for making slides to record Mn with a fluorescent microscope. A significantly greater proportion of lung cells were found to enter cell cycle with extended S-phase due to AFB1 treatment. Mn were induced in polychromatic erythrocytes (PCE) as compared to normochromatic erythrocytes (NCE) in the bone marrow of AFB1-treated rats, where there was nearly a three-fold increase in the number of Mn of bone marrow cells. The administration of AFB1 resulted in a two-fold rise in the Mn in the lung cells. The effect of BSO, DEM, and PB, the modulators of AFB1 metabolism, was studied on AFB1-induced Mn formation. A significant increase in the Mn score in PCEs of BSO- and DEM-treated rats was noted, while a slight reduction in the Mn score was noted in the case of PB-treated rats. The administration of the methanol extract of the leaves of Piper argyrophyllum (taken up in DMSO) to rats for a week exhibited normalising effect on AFB1-induced Mn in bone marrow cells. These observations record the induction of Mn in lung cells due to AFB1 for the first time. We propose the utility of AFB1-induced Mn as a model for screening plant extracts as inhibitors of genotoxicity. Prevention of genotoxic changes described above by phytochemicals is being pursued in our Laboratories.

Nitric oxide dependent killing of mycobacterium tuberculosis by human mononuclear phagocytes from patients with active tuberculosis

In this study we have demonstrated that nitric oxide, the product of the arginine dependent pathway of human mononuclear phagocytes effectively kills the M.tuberculosis in-vitro. The release of reactive nitrogen intermediates was triggered by incubation with various proinflammatory cytokines namely IFN gamma,TNF-alpha and IL-1R. We have earlier shown that human mononuclear phagocytes can be induced to release nitric,oxide (NO) radicals which can kill tumour cells. In the present communication, by using colony forming assays we demonstrated that human mononuclear phagocytes can effectively kill M.tuberculosis by using a NO dependent pathway. Treatment of mononuclear phagocytes with L-arginine resulted in markedly increased killing activity whereas, by using NGMMA, an analogue of L-arginine, the cidal activity could be brought down to the basal level. These results clearly suggest that cytokines, particularly IFN-gamma, induced NO release and its reactive product with oxygen radical, peroxynitrite, could play an important role in the killing of M. tuberculosis by human mononuclear phagocytes. A significant production of interleukin-4 and interleukin-10, by the ex-vivo matured, untreated macrophages from the active tuberculosis patients indicate that regulation of cytokine network to encourage in situ/local production of nitric oxide may be useful in the management of pulmonary tuberculosis.

Sterilization of slide sheath anesthetic injection systems placed within sharps containers

The purpose of this study was to evaluate the effect that two steam autoclaves and an unsaturated chemical vapor sterilizer had on killing bacterial endospores present on commercial spore strips or applied to sterile anesthetic injection systems placed within sharps containers. Three types of sterilizers were used: a gravity steam autoclave, a high vacuum steam autoclave and an unsaturated chemical vapor sterilizer. The microbial challenge for the sterilizers were Bacillus stearothermophilus spores present on commercial spore strips or drawn into and applied onto sliding sheath anesthetic injection systems with anesthetic carpules attached. Spore-soiled items were placed into the middle of sharps containers three-quarters-filled with representative clinical waste and sterilized. If, after culturing, sterilization of all test items in a group was not achieved, additional sterilization time was applied. Spore strips were killed within a single cycle of each sterilizer. Spore-soiled injection systems and carpules could not be routinely sterilized in the gravity steam autoclave or unsaturated chemical vapor sterilizers, even after three consecutive sterilization cycles. These items, however, were sterilized by exposure to a single-treatment cycle in a high-vacuum steam autoclave. Results indicate that routine sterilization of spore contaminated anesthetic carpules or injection systems could not be accomplished in a reasonable amount of time using sterilizers commonly found in dental offices.

Blood, bone marrow and splenic lymphocyte subset profiles in Indian visceral leishmaniasis

We examined the lymphocyte subsets in peripheral blood, bone marrow and spleen of 11 patients with acute visceral leishmaniasis (VL) and 9 with chronic VL before and after 8 weeks of antileishmanial therapy. On admission, the CD4 cell count was depressed in the peripheral blood of acute and chronic VL cases as compared to the value in 10 normal control subjects. In contrast, CD4 cell counts were higher in the bone marrow in acute and chronic cases, and in splenic aspirates of chronic cases only, compared to normal values. The peripheral blood CD8 cell count, while normal in acute cases, was uniformly low in chronic cases. Counts of CD8 cells were also low in bone marrow of acute and chronic cases, as well as in splenic aspirates of chronic cases only. All these differences were significant (P < 0.05). After treatment, the CD4 cell count in the peripheral blood increased, but decreased in bone marrow and splenic aspirates. The CD8 cell count remained unaltered in the peripheral blood but increased significantly (P < 0.05) in bone marrow and spleen. The results suggest that in VL the peripheral blood picture may not reveal the actual T cell subset profile in the reticuloendothelial system. The changes in CD8 cell counts in the bone marrow and spleen seem to be independent, and are probably influenced by antileishmanial therapy.

Purification, microsequencing, and immunolocalization of p36, a new interferon-alpha-induced protein that is associated with human lupus inclusions

The trace interferon-alpha-induced protein, p36, was induced in Raji cells in association with lupus inclusions. It was solubilized in a nonionic detergent buffer, enriched by differential centrifugation and by preparative isoelectric focusing, and purified to homogeneity on two-dimensional protein gels. Failure to obtain N-terminal amino acid sequence, however, suggested a blocked alpha-amino group. Sequences of six tryptic peptides, 13-19 amino acids in length, were obtained after digestion, microbore-high performance liquid chromotography purification, and chemical sequence analysis. None of the six sequences, which represented approximately 25% of the entire protein, shared any meaningful homologies with entries in protein sequence repositories. Raji-cell p36 was shown in Western blots with antipeptide antibodies to be induced at least 400-fold and by immunofluorescence microscopy to co-localize with the endoplasmic reticulum resident protein, protein disulfide isomerase. These results show that p36 is a new interferon-alpha-induced protein that localizes in the endoplasmic reticulum, the cell region in which the lupus inclusions form, and that p36 is probably physically associated with the lupus inclusions.

Proinflammatory cytokines can significantly induce human mononuclear phagocytes to produce nitric oxide by a cell maturation-dependent process

The capacity of three proinflammatory cytokines, interferon-gamma (rhifn-gamma), tumour-necrosis factor-alpha (rHTNF-alpha) and interleukin-1 (rHIL-1), to induce release of nitric oxide (NO) from human mononuclear phagocytes were investigated. Peripheral blood monocytes were either used immediately or after culturing in vitro to develop into monocyte-derived macrophages (macrophages). Lipopolysaccharide (LPS) was used as second signal in all experiments. The three cytokines tested had significantly high enhancing influence on the production of nitric oxide by monocytes as well as by macrophages. However production was significantly higher by the monocytes matured in vitro to macrophages (P < 0.01). In our experimental system LPS had only marginal synergistic influence on production of NO2, and IFN-gamma demonstrated to be the most efficient of the three cytokines tested. Addition of L-arginine in the monocytes/macrophages culture further amplified production of NO2, whereas addition of NG-monomethylarginine abrogated this amplification. We conclude that human mononuclear phagocytes are capable of using inducible nitric oxide synthase pathway to produce nitric oxide.

Dysregulation of homeostasis of blood T-lymphocyte subpopulations persists in chronic multibacillary pulmonary tuberculosis patients refractory to treatment

DESIGN

The dysregulation of homeostasis of blood-T lymphocyte subpopulations was studied in 21 cases of chronic, multibacillary pulmonary tuberculosis refractory to treatment. The clinico-bacteriological and immunological parameters studied in these cases (Gr A) were compared with those of a group of 10 newly-diagnosed drug sensitive cases of pulmonary tuberculosis (Gr B) at the beginning of the study and after 3 months of chemotherapy for tuberculosis. The chronic cases were treated with drugs selected from a reserve line. 10 normal healthy individuals were included in this study as a control group.

RESULTS

At the beginning of the study the mean CD4/CD8 lymphocyte ratios in the refractory cases (0.69) and the newly diagnosed cases (0.81) were significantly lower than those of the normal control subjects (1.84). After 3 months of chemotherapy all but 3 of the newly-diagnosed cases showed clinical improvement, and all became sputum-negative. Their CD4/CD8 ratio recorded a rise to near normal (1.54). On the contrary, following 3 months of reserve-line regimen, only 7 of the 21 group A cases showed sputum conversion. In all of the refractory cases, irrespective of sputum conversion, the CD4/CD8 ratio remained low (1.05).

CONCLUSION

This probably indicates that due to a long-standing bacillary load in drug resistant pulmonary tuberculosis patients the dysregulation of homeostasis of blood-T lymphocytes becomes persistent. This in turn delays their clinical and immunological recovery, even when therapy is adequate.