bluuebunny/crossref_metadata_2025 huggingface dataset:
Nutritional Knowledge, WASH Practices of Mothers and Their Impact on the Nutritional Status of Children Aged 6–59 Months in Cumilla District, Bangladesh
Authors: Hossain Md. Shahadoth , Akter Tasniya , Sadiq Md. Zafar As
Published: January 2024

Introduction: Child malnutrition is a pressing global public health issue, impacting both immediate health and future development. Adequate nutrition is a crucial aspect of public health, with maternal nutritional knowledge playing a vital role in ensuring optimal growth for children. Insufficient awareness about nutrition, even in households with sufficient resources, can result in poor outcomes for children.

Aim: This study aimed to explore the contemporary status of maternal nutritional knowledge, water, sanitation, and hygiene (WASH) practices and their effect on the nutritional status of children aged 6–59 months in the Cumilla district of Bangladesh.

Methods: A community-based cross-sectional study was carried out on 386 mother-child (6-59 months) pairs from 7 villages of the Cumilla district, Bangladesh. The study was designed to assess nutritional knowledge, WASH practices of mothers and nutritional status of their children using structured questionnaire and anthropometric measures. Chi square test was performed to investigate the association between maternal nutritional knowledge, WASH practices, and the nutritional status of children.

Results: The study revealed, the level of nutritional knowledge was average (72.3%) among mothers. The prevalence of stunting, underweight, wasting and overweight were 38.6%, 16.9%, 11.9%, and 7.8% respectively. A strong relationship was found between nutritional knowledge, WASH practices of mothers and child’s stunting (p<0.05) respectively. Maternal nutritional knowledge also had a strong association with underweight where female child was more prone to underweight than its male counterpart (p<0.05). There was no significant association between maternal nutritional knowledge, WASH practices and wasting (p = 0.224, p = 0.328) respectively.

Conclusion: The study revealed elevated rates of stunting and overweight in children compared to the national average, while underweight prevalence was lower and wasting prevalence was similar. Therefore, it is crucial to tackle social and cultural issues and implement effective strategies to enhance maternal nutritional knowledge and WASH practices to mitigate malnutrition in the rural areas of Bangladesh.
Prevalence of Dental Caries in Permanent Second Molars in Teenagers Using ICDAS
Authors: Rithanya M. , Mathew Mebin George
Published: January 2024

Introduction: Dental caries is a chronic disease of the tooth which is represented by demineralisation and destruction of the organic matter of the tooth. Dental caries are versatile, capable of affecting the crown portion of the tooth initially, and may affect the unprotected root surfaces later on. International Caries Detection and Assessment System (ICDAS) provides a systematic approach of reviewing the available clinical dental caries to evaluate the development of dental caries

Materials and Methods: This study is a single centered retrospective study in which the data was collected from a private dental college and hospital in Chennai, India. Patient details were collected from the hospital management system and a total of 1804 samples were collected. The data was tabulated using Excel and then statistically analysed using the latest version of SPSS software.

Results and Discussion: The prevalence of ICDAS score 3 in second molars is higher in 17 year old patients with 2.88% in maxillary right second molars, 3.33% in maxillary left second molars, 3.55% in mandibular left second molars and 3.71% in mandibular right second molars. The prevalence of dental caries in permanent second molar is 9.34%. It is seen that ICDAS score 3 is 8.71% prevalent followed by ICDAS score 5 which is 0.63%.

Conclusion: Within the limitations of the study, it was found that the prevalence of dental caries in permanent second molars is 9.34% with ICDAS score 3 being the most prevalent followed by ICDAS score 5 which is 0.63%.
Melatonin synthesis: A possible indicator of intolerance to shiftwork
Authors: Griefahn Barbara , Künemund Christa , Golka Klaus , Thier Ricarda , Degen Gisela
Published: October 2002

Hypothesis

Melatonin synthesis, which is directly controlled by the central circadian pacemaker indicates the circadian phase better than rectal temperature.

Methods

Thirty four men (16–32 years, 7 morning, 13 neither, 14 evening types) performed a constant routine (24–26‐hr bedrest, < 30 lux, 18–20°C, hourly isocaloric diet). Salivary melatonin level was determined hourly and rectal temperature was continuously recorded.

Results

The nadir of rectal temperature occurred 1.5 hr (P = 0.017), the onset of melatonin synthesis 3 hr earlier (P < 0.0001) in morning than in evening types. Morningness was not related to the quantitative but significantly to the temporal parameters, closer to those of melatonin than of rectal temperature.

Conclusions

The melatonin onset is a more reliable indicator of the diurnal type than the nadir of rectal temperature. As morningness has been associated with intolerance to shiftwork, melatonin profiling provides a suitable basis for the establishment of directed preventive measures. Am. J. Ind. Med. 42:427–436, 2002. © 2002 Wiley‐Liss, Inc.
Micelle‐bound conformation of a hairpin‐forming peptide: Combined NMR and molecular dynamics study
Authors: Dixon Ann M. , Venable Richard M. , Pastor Richard W. , Bull T. E.
Published: October 2002

A peptide fragment from a protein hairpin turn region was modified by addition of isoleucine residues to both ends to enhance binding to lipid micelles; the resulting peptide (I1‐I2‐C3‐N4‐N5‐P6‐H7‐I8‐I9) contains the core sequence I‐C‐N‐N‐P‐H from an antibody‐binding region of hemagglutinin A. Nuclear magnetic resonance (NMR) diffusion measurements indicated partial binding (43–65%) of the peptide to micelles of n‐octylglucoside and significantly stronger binding (85%) to dodecylphosphocholine (DPC) micelles. Simulated annealing and conformational analysis using nuclear Overhauser enhancement restraints revealed a type I or III hairpin turn between residues N5 and I8 of the DPC‐bound peptide. Amide exchange experiments support the possibility that a hydrogen bond forms between N5 and I8, stabilizing the turn. In contrast, no discernable structure was observed for the peptide in aqueous solution by either NMR or circular dichroism. Molecular dynamics simulations of DPC micelles and peptide–micelle complexes suggested that the peptide lies flat on the micelle surface and showed rapid rearrangement of the lipids to accommodate the bound peptide. According to a search performed using the basic local alignment search tool (BLAST), the sequences N‐P‐H‐I and N‐P‐H‐V are present as hairpin turns in eight of the nine proteins whose crystal structures were available. The addition of isoleucine residues and the use of lipid micelles to stabilize hairpin conformations equivalent to those found in proteins generates new possibilities for reproducing biologically important hairpin turns from short, linear peptides. Published 2002 Wiley Periodicals, Inc. Biopolymers 65: 284–298, 2002
Molecular cytogenetic analysis of genomic instability at the 1q12–22 chromosomal site in B‐cell non‐Hodgkin lymphoma
Authors: Itoyama Takahiro , Nanjungud Gouri , Chen Weiyi , Dyomin Vadim G. , Teruya‐Feldstein Julie , Jhanwar Suresh C. , Zelenetz Andrew D. , Chaganti R.S.K.
Published: October 2002

Abnormalities of chromosome arm 1q have frequently been reported in B‐cell non‐Hodgkin lymphoma (NHL), and correlated with poor outcome. Five genes mapped to this region (BCL9, MUC1, FCGR2B, IRTA1, and RTA2) have been shown to be deregulated by juxtaposition with the IG genes. However, abnormalities of the 1q21–22 region that are not involved in translocations with the IG genes have not been addressed. We performed a molecular cytogenetic analysis of 1q12–22 abnormalities in 24 B‐cell NHL cases. The cases analyzed were in two groups: one, composed of 18 cases with the single break in the 1q12–22 region, and another, composed of six cases with multiple breaks in the 1q12–22 region. The involvement of heterochromatin and its vicinity was observed most frequently in the single‐break cases (13 of 18 cases). In this group, the recurring partner region was 1q32, which resulted in dup(1)(q12‐21q32) or trp(1)(q12q32) in 5 cases. The 6 cases with multiple breaks showed an unexpected level of instability along with complex combinations of abnormalities, especially sequential duplication and inversion, in the 1q12–22 region. The BCL9 locus was deleted by complex aberration in 2 of 6 cases. High‐level amplification of the WI‐16757 locus was found in 2 cases. Our studies demonstrate a high level of instability of the 1q12–22 region, possibly stemming from its chromatin organization. Chromosome arm 1q is gene‐rich, and characterization of aberrations described in this study can be expected to lead to the discovery of additional functionally significant genetic changes. © 2002 Wiley‐Liss, Inc.
Frequent amplification of 8q24, 11q, 17q, and 20q‐specific genes in pancreatic cancer
Authors: Mahlamäki Eija H. , Bärlund Maarit , Tanner Minna , Gorunova Ludmila , Höglund Mattias , Karhu Ritva , Kallioniemi Anne
Published: October 2002

Genetic changes involved in the development and progression of pancreatic cancer are still partly unknown, despite the progress in recent years. In this study, comparative genomic hybridization analysis in 31 pancreatic cancer cell lines showed that chromosome arms 8q, 11q, 17q, and 20q are frequently gained in this tumor type. Copy number analysis of selected genes from these chromosome arms by fluorescence in situ hybridization showed amplification of the MYC oncogene in 54% of the cell lines, whereas CCND1 was amplified in 28%. In the 17q arm, the ERBB2 oncogene was amplified in 20% of the cell lines, TBX2 in 50%, and BIRC5 in 58%, indicating increased involvement toward the q telomere of chromosome 17. In the 20q arm, the amplification frequencies varied from 32% to 83%, with the CTSZ gene at 20q13 being most frequently affected. These results illustrate that amplification of genes from the 8q, 11q, 17q, and 20q chromosome arms is common in pancreatic cancer. © 2002 Wiley‐Liss, Inc.
Somatic von Hippel–Lindau disease gene mutation in clear‐cell renal carcinomas associated with end‐stage renal disease/acquired cystic disease of the kidney
Authors: Yoshida Minoru , Yao Masahiro , Ishikawa Isao , Kishida Takeshi , Nagashima Yoji , Kondo Kei‐ichi , Nakaigawa Noboru , Hosaka Masahiko
Published: October 2002

It has been documented that renal cell carcinomas (RCCs) occur frequently in patients treated with long‐term dialysis, especially in cases of end‐stage renal disease (ESRD)/acquired cystic disease of the kidney (ACDK). To address the molecular pathogenesis of ESRD/ACDK‐associated RCCs, we examined 14 RCCs (7 clear‐cell and 7 papillary carcinomas) in patients receiving dialysis for somatic mutations of the von Hippel–Lindau disease (VHL) gene as well as of the tyrosine kinase domain of the MET oncogene. Direct sequencing analyses revealed that three tumors exhibited VHL frameshifts (618delA, 386–395del10‐bp, and 723–724insTC). One of the VHL mutated tumors showed additional loss of heterozygosity at the VHL gene locus. Histopathologic and clinical data demonstrated that the three tumors having VHL mutations were clear‐cell RCCs occurring in ESRD with 55, 106, and 156 months of dialysis history, respectively. We did not find any tumors with mutations in the tyrosine kinase domain of the MET. These results demonstrated that the VHL tumor‐suppressor gene is also involved in a subset of clear‐cell RCCs occurring in ESRD/ACDK, as in the case of sporadic clear‐cell RCCs. However, mutations of the MET oncogene could not be found in the seven ESRD/ACDK‐associated papillary RCCs examined. © 2003 Wiley‐Liss, Inc.
Molecular genetic characterization of the EWS/CHN and RBP56/CHN fusion genes in extraskeletal myxoid chondrosarcoma
Authors: Panagopoulos Ioannis , Mertens Fredrik , Isaksson Margareth , Domanski Henryk A. , Brosjö Otte , Heim Sverre , Bjerkehagen Bodil , Sciot Raf , Dal Cin Paola , Fletcher Jonathan A. , Fletcher Christopher D. M. , Mandahl Nils
Published: October 2002

Extraskeletal myxoid chondrosarcoma (EMC) is a soft‐tissue neoplasm cytogenetically characterized by the translocations t(9;22)(q22;q11–12) or t(9;17)(q22;q11), generating EWS/CHN or RBP56/CHN fusion genes, respectively. In the present study, 18 EMCs were studied both cytogenetically and at the molecular level. Chromosomal aberrations were detected in 16 samples: 13 with involvement of 9q22 and 22q11–12, and three with rearrangements of 9q22 and 17q11. Fifteen cases had an EWS/CHN fusion transcript and three had an RBP56/CHN transcript. The most frequent EWS/CHN transcript (type 1; 10 tumors), involved fusion of EWS exon 12 with CHN exon 3, and the second most common (type 5; two cases) was fusion of EWS exon 13 with CHN exon 3. In all tumors with RBP56/CHN fusion, exon 6 of RBP56 was fused to exon 3 of CHN. By genomic XL PCR and sequence analyses, the breakpoints from 14 cases were mapped in the EWS, RBP56, and CHN genes. In CHN, 12 breakpoints were found in intron 2 and only two in intron 1. In EWS, the breaks occurred in introns 7 (one break), 12 (eight breaks), and 13 (one break), and in RBP56 in intron 6. Repetitive elements such as Alu and LINE sequences seem to have limited, if any, importance in the genesis of EWS/CHN and RBP56/CHN chimeras. Furthermore, there were no chi, chi‐like, topoisomerase II, or translin consensus sequences in the introns harboring the translocation breakpoints, nor could the number of topo I sites in EWS, RBP56, and CHN introns explain the uneven distribution of the breakpoints among EWS or CHN introns. Additional genetic events, such as nucleotide insertions, homologies at the junction, deletions, duplications, and inversions, were found to accompany the translocations, indicating that the chromosomal translocations do not require sequence‐specific recombinases or extensive homology between the recombined sequences. © 2002 Wiley‐Liss, Inc.
Cell lines in inner ear research
Authors: Rivolta Marcelo N. , Holley Matthew C.
Published: October 2002

Cell lines have provided important experimental tools that have enhanced our understanding of neural and sensory function. They are particularly valuable in inner ear research because the auditory and vestibular systems are small, complex, and encased in several layers of bone. Organotypic cultures provide an invaluable experimental resource but require repeated microdissection and culture, and remain complex in terms of cell types and states of differentiation. A number of laboratories have established cell lines that offer a range of potential applications to hearing research. This review describes the advances that have already been made with these lines and the potential applications that they offer in the future. The majority of the cell lines are immortalized with a conditionally expressed, temperature sensitive variant of the SV40 tumor antigen. We discuss the value of these cells in developmental studies. © 2002 Wiley Periodicals, Inc. J Neurobiol 53: 306–318, 2002
Towards a molecular understanding of drosophila hearing
Authors: Caldwell Jason C. , Eberl Daniel F.
Published: October 2002

The Drosophila auditory system is presented as a powerful new genetic model system for understanding the molecular aspects of development and physiology of hearing organs. The fly's ear resides in the antenna, with Johnston's organ serving as the mechanoreceptor. New approaches using electrophysiology and laser vibrometry have provided useful tools to apply to the study of mutations that disrupt hearing. The fundamental developmental processes that generate the peripheral nervous system are fairly well understood, although specific variations of these processes for chordotonal organs (CHO) and especially for Johnston's organ require more scrutiny. In contrast, even the fundamental physiologic workings of mechanosensitive systems are still poorly understood, but rapid recent progress is beginning to shed light. The identification and analysis of mutations that affect auditory function are summarized here, and prospects for the role of the Drosophila auditory system in understanding both insect and vertebrate hearing are discussed. © 2002 Wiley Periodicals, Inc. J Neurobiol 53: 172–189, 2002
Parallel and antiparallel dimers of magainin 2: their interaction with phospholipid membrane and antibacterial activity
Authors: Mukai Yasuhiro , Matsushita Yuko , Niidome Takuro , Hatekeyama Tomomitsu , Aoyagi Haruhiko
Published: October 2002

Magainin 2 (M2) forms pores by associating with several other M2 molecules in lipid membranes and shows antibacterial activity. To examine the effect of M2 dimerization on biological activity and membrane interaction, parallel and antiparallel M2 dimers were prepared from two monomeric precursors. Antibacterial and haemolytic activities were enhanced by dimerization. CD measurements showed that both dimers and monomers have an α‐helical structure in the presence of lipid vesicles. Tryptophan fluorescence shift and KI quenching studies showed that all the peptides were more deeply embedded in acidic liposomes than in neutral liposomes. Experiments on dye‐leakage activity and membrane translocation of peptides suggest that dimers and monomers form pores through lipid membranes, although the pore formation may be accompanied by membrane disturbance. Although dimerization of M2 increased the interaction activity with lipid membranes, no appreciable difference between the activities of parallel and antiparallel M2 dimers was observed. Copyright © 2002 European Peptide Society and John Wiley & Sons, Ltd.
In Vitro Pharmacodynamic Properties of Three Antifungal Agents against PreformedCandida albicansBiofilms Determined by Time-Kill Studies
Authors: Ramage Gordon , VandeWalle Kacy , Bachmann Stefano P. , Wickes Brian L. , López-Ribot José L.
Published: October 2002

We have examined the in vitro activities of fluconazole, amphotericin B, and caspofungin againstCandida albicansbiofilms by time-kill methodology. Fluconazole was ineffective against biofilms. Killing of biofilm cells was suboptimal at therapeutic concentrations of amphotericin B. Caspofungin displayed the most effective pharmacokinetic properties, with ≥99% killing at physiological concentrations.
Molecular Characterization of Integrons in Epidemiologically Unrelated Clinical Isolates of
Acinetobacter baumannii
from Italian Hospitals Reveals a Limited Diversity of Gene Cassette Arrays
Authors: Gombac Francesca , Riccio Maria Letizia , Rossolini Gian Maria , Lagatolla Cristina , Tonin Enrico , Monti-Bragadin Carlo , Lavenia Annamaria , Dolzani Lucilla
Published: October 2002

Integron carriage by 36 epidemiologically unrelated
Acinetobacter baumannii
isolates collected over an 11-year period from patients in six different Italian hospitals was investigated. Sixteen type 1 integron-positive isolates (44%) were found, 13 of which carried the same array of cassettes, i.e.,
aacC1
, orfX, orfX′, and
aadA1a.
As ribotype analysis of the isolates demonstrated a notable genetic diversity, horizontal transfer of the entire integron structure or ancient acquisition was hypothesized.
COMPUTATIONAL COMPLEXITY OF ARBITRAGE IN FRICTIONAL SECURITY MARKET
Authors: DENG XIAOTIE , LI ZHONG-FEI , WANG SHOU-YANG
Published: October 2002

We are interested in computation of arbitrage condition in financial market with friction. We consider a deterministic model with a finite number of financial assets and a finite number of possible states of nature. The future return of each asset under each possible state of nature is given in the model. We derive a negative result on computational complexity of arbitrage in the case when assets are traded in integer numbers of shares and with a maximum amount of shares that can be bought for a fixed price.
RIGID PROJECTILE MODEL DESCRIPTION OF α-NUCLEUS TOTAL REACTION CROSS SECTIONS
Authors: AHMAD I. , ABDULMOMEN M. A. , AL-KHATTABI L. A.
Published: October 2002

Working within the framework of Coulomb modified Glauber theory, we calculate α particle total reaction cross sections for 12 C , 16 O , 28 Si , 40,48 Ca , 58,60 Ni and 124 Sn at medium energies in the rigid projectile model using the parameters of the phenomenological N–α amplitude. A comparison with the available experimental data shows that, in general, the results of the present calculation are in much better agreement with the data compared to those of the optical limit calculation using the free NN total cross sections.
MEASUREMENT IN QUANTUM PHYSICS
Authors: DANOS MICHAEL , KIEU TIEN D.
Published: October 2002

The conceptual problems in quantum mechanics — related to the collapse of the wave function, the particle-wave duality, the meaning of measurement — arise from the need to ascribe particle character to the wave function. As will be shown, all these problems dissolve when working instead with quantum fields, which have both wave and particle character. Otherwise the predictions of quantum physics, including Bell's inequalities, coincide with those of the conventional treatments. The process of decoherence which governs the transfer of the results of the quantum measurement to the classical realm is also carefully discussed.
TIME-SYMMETRY AND IRREVERSIBILITY IN CHRONOTOPOLOGICAL QFT — APPLICATION TO THE CP- AND T-SYMMETRY VIOLATIONS
Authors: SYROS C.
Published: October 2002

A quantum logical alternative "Either non-measure preservation Or unitary evolution" exists in the framework of Schroedinger's theory. This explains irreversibility and allows to describe both time-symmetric and time-asymmetric processes in Hermitian quantum theory. The CPT and Noether's theorems remain valid in chronotopology. The Bohr-Einstein controversy, Wigner's conjecture and the Poincaré's non-recurrence are naturally explained. Extended numerical calculations correctly predict the CP- and T-symmetry violation coefficients |η2π0|, |ηπ±|, |ημ±|, |ηe±|, [Formula: see text] and their phase angles: arg (η)=ϕ2π0, ϕπ±, ϕμ±, ϕe± for the K0, [Formula: see text]-decays. A relationship is discovered between the mixing factor and the relevant matrix elements. The ratio "matter/antimatter" appears as temperature dependent in the Universe, antimatter decays prevailing at around T≥ 1024 Kelvin.
The alternative transcript of CD79b is overexpressed in B-CLL and inhibits signaling for apoptosis
Authors: Cragg Mark S. , Chan H. T. Claude , Fox Mathew D. , Tutt Alison , Smith Aimée , Oscier David G. , Hamblin Terry J. , Glennie Martin J.
Published: October 2002

The B-cell receptor (BCR) for antigen is composed of surface immunoglobulin (sIg), which provides antigen specificity, and a noncovalently associated signaling unit, the CD79a/b heterodimer. Defects in CD79 can influence both BCR expression and signaling and may explain why cells from certain malignancies, such as B-chronic lymphocytic leukemia (B-CLL), often express diminished and inactive BCR. Recently, an alternative transcript of CD79b (ΔCD79b) has been reported that is up-regulated in B-CLL and may explain this diminished BCR expression. Here we assess the expression of ΔCD79b in B-CLL and other lymphoid malignancies and investigate its function. High relative expression of ΔCD79b was confirmed in most cases of B-CLL and found in 6 of 6 cases of splenic lymphomas with villous lymphocytes (SLVLs) and hairy cell leukemia. In a range of Burkitt lymphoma cell lines, expression of ΔCD79b was relatively low but correlated inversely with the ability of the BCR to signal apoptosis when cross-linked by antibody (Ab). Interestingly, when Ramos-EHRB cells, which express low ΔCD79b, were transfected with this transcript, they were transformed from being sensitive to anti-Fcμ–induced apoptosis to being highly resistant. Although ΔCD79b was expressed as protein, its overexpression did not reduce the level of cell surface BCR. Finally, we showed that the inhibitory activity of ΔCD79b depended on an intact leader sequence to ensure endoplasmic reticulum (ER) trafficking and a functional signaling immunoreceptor tyrosine-based activation motif (ITAM) in its cytoplasmic tail. These results point to ΔCD79b being a powerful modulator of BCR signaling that may play an important role in normal and malignant B cells.
Enforced expression of tissue inhibitor of matrix metalloproteinase-3 affects functional capillary morphogenesis and inhibits tumor growth in a murine tumor model
Authors: Spurbeck William W. , Ng Catherine Y. C. , Strom Ted S. , Vanin Elio F. , Davidoff Andrew M.
Published: October 2002

Homeostasis of the extracellular matrix is a delicate balance between degradation and remodeling, the balance being maintained by the interaction of activated matrix metalloproteinases (MMPs) and specific tissue inhibitors of matrix metalloproteinases (TIMPs). Up-regulation of MMP activity, favoring proteolytic degradation of the basement membrane and extracellular matrix, has been linked to tumor growth and metastasis, as well as tumor-associated angiogenesis, whereas inhibition of MMP activity appears to restrict these processes. We have used retroviral-mediated gene delivery to effect sustained autocrine expression of TIMP-3 in murine neuroblastoma and melanoma tumor cells in order to further examine the ability of TIMPs to inhibit angiogenesis in vivo. Growth of both histologic types of gene-modified tumor cells in severe combined immunodeficiency (SCID) mice was significantly restricted when compared with controls. Grossly, these tumors were small and had few feeding vessels. Histologic evaluation revealed that although tumors overexpressing TIMP-3 had an increased number of CD31+endothelial cells, these endothelial cells had not formed functional tubules, as evidenced by decreased vessel continuity and minimal pericyte recruitment. This effect appears to be mediated, in part, by decreased expression of vascular endothelial (VE)–cadherin by endothelial cells in the presence of TIMP-3 as seen both in an in vitro assay and in TIMP-3–overexpressing tumors. Taken together, these results demonstrate that overexpression of TIMP-3 can inhibit angiogenesis and associated tumor growth, and that the antiangiogenic effects of TIMP-3 appear to be mediated through the inhibition of functional capillary morphogenesis.
Architecture of a Novel Binucleating SNONS Compartmental Ligand: Physico-Chemical Investigation of Its Metal Complexes
Authors: Naik Anil , Annigeri Satish , Gangadharmath Umesh , Revankar Vidyanand , Mahale Vinayak , Reddy Vijaykumar
Published: October 2002

The preparation of a novel pentadentate binucleating compartmental ligand, 2-hydroxy-5-methylisophthalaldehyde bis(p-methoxy thiobenzoylhydrazone), is described together with the corresponding chloro-bridged cobalt(II), nickel(II), copper(II) and zinc(II) complexes, which were characterized based on spectral, magnetic, thermal and electrochemical studies. Cryomagnetic investigations (77–296 K) reveal a strong antiferromagnetic spin-exchange between the copper(II) ions (J based on H = −2JS1. S2 is 305 cm−1). An electrochemical study of the copper(II) complex shows two distinct quasi-reversible redox peaks (E11/2 = −0.4 and E21/2 = −0.69 V vs saturated calomel electrode), indicating a stepwise reduction of the copper centers (CuIICuII → CuIICuI and CuIICuI → CuICuI). The EPR spectrum is typical of a “rhombic compressed local molecular environment”. The ligand and its copper and zinc complexes exhibit fluorescence at room temperature in DMF. All of the compounds under study were screened for antimicrobial action.
2,4,4,6-Tetrabromo-2,5-cyclohexadienone (TABCO) as a Versatile, Efficient, and Chemoselective Catalyst for the Acetalization and Transacetalization of Carbonyl Compounds, the Preparation of Acetonides from Epoxides and Acylals (1,1-Diacetates) from Aldehydes
Authors: Firouzabadi Habib , Iranpoor Nasser , Shaterian Hamid Reza
Published: October 2002

The efficient and chemoselective preparation of acetals and ketals from carbonyl compounds, transacetalization reactions, the conversion of epoxides to acetonides, and the preparation of acylals from aldehydes in the presence of catalytic amounts of 2,4,4,6-tetrabromo-2,5-cyclohexadienone (TABCO) are described.
Effects of Chiral Additives on Enantioselectivity for Lipase-Catalyzed Esterifications in an Organic Solvent. A Remarkable Enhancement of Its Enantioselectivity Due to Cooperative Effects of Two Kinds of Additives
Authors: Ueji Shin-ichi , Sakamoto Hideyuki , Watanabe Keiichi , Okamoto Takashi , Mori Shuichi
Published: October 2002

The enantioselectivity for the lipase-catalyzed esterifications in an organic solvent was found to be enhanced by addition of (+)- or (−)-camphor as a chiral additive. A more remarkable enhancement of its enantioselectivity was brought about by the cooperative effects of two kinds of additives: (−)-camphor and water.
Fume Pyrolysis of Nickel-Containing Silica Sol for the Preparation of a Microporous Ni/SiO2 Catalyst and a Comparison with Other Nickel-Loading Methods onto Microporous Silica
Authors: Mizushima Takanori , Nishida Kenji , Ohkita Hironobu , Kakuta Noriyoshi
Published: October 2002

A fume pyrolysis technique using a nickel-containing tetraethoxysilan solution was applied to the preparation of a microporous and highly dispersed Ni/SiO2 catalyst and compared with nickel-loading onto microporous silica by the conventional impregnation and ion-exchange methods. During impregnation, although the microporous structure remained unaltered, large Ni particles were deposited onto the external surface of the silica particles. Although the ion-exchange method resulted in a high dispersion, the process eroded the silica texture and lowered the pore volume remarkably. In contrast, the fume pyrolysis of a spray of a solution consisting of nickel-incorporated siloxane polymers, prepared through an alkoxide procedure, formed a catalyst which had very small Ni particles in micropores of silica. In spite of the same precursory solution, a simple dryness by evaporation led to pore expansion into the mesopore region and a decrease in the Ni dispersion.
Evaluation of assays of serum IgG subclasses and IgG antigen-specific antibodies in the investigation of recurrent infection
Authors: Read G F , Williams P E
Published: October 2002

Patients who have recurrent infections require laboratory investigation for possible underlying immunodeficiency. We retrospectively evaluated the usefulness of two relevant assays (serum IgG subclass concentration and levels of IgG antigen-specific antibodies to a panel of relevant carbohydrate and protein antigens) in the management of patients referred to a regional clinical immunology service over a 3-year period. Of 97 patients for whom both assays were performed, five (5·2% ) had a low result for IgG subclasses but this did not influence the management of any patient; 51 patients (53%) had a low result for antigen-specific antibodies and this influenced management in 43 cases. We conclude that knowledge of the serum IgG subclass concentrations is of dubious relevance and this calls into question whether the assay should continue to be offered. This regional service has ceased to perform the assay routinely in such patients. Our findings require confirmation by a larger multicentre study that should assess the clinical outcome of any changes in practice.
New method for faecal fat determination by mid-infrared spectroscopy, using a transmission cell: an improvement in standardization
Authors: Jakobs B S , Volmer M , Swinkels D W , Hofs M T W , Donkervoort S , Joosting M M J , Wolthers B G , de Peinder P , Voorbij H A M
Published: October 2002

Current techniques used in clinical laboratories for faecal fat determination, such as the Van de Kamer method, are not very accurate or precise. This became apparent when results obtained by different laboratories were compared, and could explain the disappointing performance of near-infrared and mid-infrared spectroscopy since the accuracy of these techniques depends upon the accuracy of the calibration used (i.e. inaccurate wet chemical analysis). In order to improve standardization, we developed and tested a new quantitative method in three laboratories, based on Fourier transform infrared (FT-IR) spectroscopy. Fatty acids were extracted from faecal samples with acidified petroleum ether-ethanol and the extracts were dried and dissolved in chloroform. An infrared spectrum of the extracts was recorded in the range 4000-650 cmx1, using an infrared transmission cell. Standard mixtures of stearic and palmitic acids (65:35) were used for calibration. Quantification was based on the absorbance band of the CH 2 group (2855 cmx1) of free fatty acids and fatty acid glycerol esters. The calibration curve showed excellent linearity. The correlation coefficient between the titrimetric Van de Kamer and FT-IR methods was 0·96 ( y=1⋅12 x 0⋅02, standard error of prediction=0⋅89 g% fat). No significant difference was found when the FT-IR results of 28 faecal samples from patients were compared between two different university hospital laboratories. The new FT-IR method, using primary standards, is simple and rapid, and provides satisfactory intra- and inter-laboratory precision for the diagnosis and monitoring of steatorrhoea.
Apo(a) isoforms do not predict risk for coronary heart disease in a Gulf Arab population
Authors: Akanji Abayomi O
Published: October 2002

It is well recognized that blood lipoprotein A [Lp(a)] levels constitute an important risk factor for atherosclerotic vascular disease. In some populations, mainly Caucasian, Lp(a) levels and coronary heart disease (CHD) risk are determined by the pattern of apolipoprotein a [apo(a)] polymorphism. It is currently unclear if these observations apply to other populations and ethnic groups. The aim of the current study is to determine to what extent known apo(a) polymorphisms associate with development of CHD in a Kuwaiti Arab population.

Serum Lp(a) levels were measured by enzyme-linked immunosorbent assay and apo(a) isoforms determined by a high-resolution sodium dodecyl sulphate/agarose gel electrophoresis with immunoblotting in two groups of Kuwaiti subjects: healthy controls ( n = 140) and subjects with CHD ( n=140). Blood lipids and anthropometric parameters were also determined in these subjects by standard methods.

Serum Lp(a) levels were greater in those with CHD than in those in the healthy group ( P<0·001). There was no consistent trend in the pattern of serum Lp(a) levels found with specific apo(a) isoforms in either group of subjects. There was, therefore, no simple relationship between the isoform pattern (and number of kringle-IV repeats) and serum Lp(a) concentration, unlike in certain other populations. Additionally, almost identical proportions of subjects in either group had singlebanded (homozygous, ~ 70%), double-banded (heterozygous, ~ 23%) and no-band (null, ~ 7%) phenotypes. The distribution of the five identified isoforms (F, S1, S2, S3 and S4) also was almost identical for both groups of subjects, whether homozygous or heterozygous, and whether classified into fast-moving (F, S1 and S2) or slow-moving (S3 and S4) isoforms.

We conclude that the frequency and pattern of distribution of apo(a) phenotypes did not differ significantly between healthy control Kuwaiti Arab subjects and those with CHD. It is thus unlikely that an individual's apo(a) phenotype can predict both serum Lp(a) level and risk for CHD, irrespective of race and/or ethnic grouping.
Micro-flowcell conductometric sweat analysis for cystic fibrosis diagnosis
Authors: Webster H Lewis , Quirante Carmelo G
Published: October 2002

This paper describes a device specifically designed to facilitate neonatal sweat testing. The components are sized appropriately for attachment to the limbs of newborns. Iontophoretic electrodes, with pilocarpine gel inserts, are latched into small holders attached by straps to the limb. The holder at the anodic site remains in place to receive and align the sensor cell, which uses a conical collecting surface to channel the sweat directly and anaerobically from the sweat ducts to the continuous flow-through conductivity cell within its body. A crib-side analysis unit incorporates an iontophoretic power supply and displays a continuous readout of sweat electrical conductivity. The average conductivity during a specific time interval and the initial sweating rate are automatically displayed. The method, which simplifies sweat tests, is currently being assessed in three neonatal clinical trials to test its ability to reduce test failures in the newborn due to insufficient sweat.
LDL subfractions in patients with myocardial infarction: effect of smoking and β-blocker treatment
Authors: Theodoraki Theodora G , Tsoukatos Demokritos C , Karabina Sonia-Athena , Rallidis Loukianos S , Papageorgakis Nikolaos H , Tselepsis Alexandros D
Published: October 2002

The aim of the present case-control study was to estimate, by density gradient ultracentrifugation, LDL heterogeneity in myocardial infarction, and to evaluate the effect of smoking and β-blocker treatment on LDL subfraction profile. Our results show that patients who survive myocardial infarction have an abundance of small, dense LDL in their plasma, compared with controls. Patients who were on β-blockers and those who smoked showed a more atherogenic LDL subfraction profile than the rest. In patients on β-blocker treatment, the proportion of LDL3 was positively correlated with triglyceride concentration and body mass index. Dense LDL predominates in patients irrespective of smoking or β-blocker treatment. The relative risk, calculated by logistic regression as the odds ratio of high LDL3, was 7·5 (95% confidence interval 2·5-22·1) and was not significantly influenced when smoking, β-blocker treatment, triglycerides or the other parameters of the study were included in the statistical model.
Near-patient test for nicotine and its metabolites in saliva to assess smoking habit
Authors: Cope Graham , Nayyar Pamela , Holder Roger , Brock Gareth , Chapple Iain
Published: October 2002

Smoking is a major risk factor for periodontal disease, causing bone and tooth loss. Effective management of many oral conditions requires accurate information about smoking. We describe a disposable, 10-min, near-patient saliva test to monitor cigarette smoking. A plastic device contains the dried reagents to measure nicotine and its metabolites by a colorimetric assay. The device can be used to give a semi-quantitative assessment of tobacco consumption by observing a colour change and comparing it to a reference chart. Alternatively, the test can be quantified by measuring the light absorbance with a colorimeter and determining the concentration of nicotine metabolites by reference to a cotinine standard. This method correlates with reported daily cigarette consumption ( r=0·62, P< 0·0001) and nicotine yield of cigarettes smoked ( r=0·35, P<0·01) and compares favourably with cotinine, as measured independently by radioimmunoassay ( r=0·57, P<0·005). The method provides a simple-to-use, inexpensive way of monitoring tobacco consumption in dental surgeries.
Capillary isotachophoretic analysis of serum lipoproteins using a carrier ampholyte as spacer ion
Authors: Inano Koichi , Tezuka Shizuo , Miida Takashi , Okada Masahiko
Published: October 2002

We have developed a novel analytical method for serum lipoproteins using a commercially available capillary electrophoresis apparatus, BioFocus 3000 (Bio-Rad Laboratories Co Ltd, USA). The analytical principle is isotachophoresis (ITP), using a carrier ampholyte, BioLyte 7/9, as a spacer ion. The method allows a much higher resolution of lipoproteins than of amino acid mixtures. Serum lipoproteins are normally separated into 13-15 peaks, including some shoulder peaks. The reproducibility of repeated analysis within a day was relatively good with the coefficient of variation within the range 0·9-1·1%. VLDL, LDL and HDL prepared by discontinuous density ultracentrifugation could be further separated by capillary ITP. This high-resolving ability of our method enabled detection of small amounts of abnormal lipoprotein species. For example, small dense LDL, which is thought to be an atherogenic lipoprotein, could be detected within the LDL group peak. Moreover, an abnormal HDL, apolipoprotein E-rich HDL, was also detected by a single analysis. These findings suggest that our capillary ITP method is a useful means for detailed analysis of lipoproteins and thus for clinical diagnosis of hyperlipoproteinaemic subjects.
Lipoprotein(a): what's in a measure?
Authors: Wieringa G
Published: October 2002

Lipoprotein(a) [Lp(a)] was first identified by Kare Berg in 1963 as an LDL variant. Subsequent studies showed it to be a family of lipoproteins whose wide density range overlaps those of low and high density lipoproteins. Although clinical interest in this particle was limited for many years, it was stimulated again in the late 1970s with the discovery that high concentrations of Lp(a) may be associated with coronary heart disease (CHD). Numerous follow-up studies confirmed that Lp(a) is an independent risk factor for CHD and that raised values are associated with the severity of CHD and with an increased risk of future cardiac events. The relative risk of myocardial infarction has been reported to be 1·75-fold higher when Lp(a) levels are raised above 300 mg/L. Clinical interest in Lp(a) has stimulated the development of commercial methods for its determination. Currently, over 15 methods are available, varying in principle, antibody specificity, standardization and method of detection. This personal view considers the impact that different methodological approaches have had on the interpretation of Lp(a) levels in clinical studies and the initiatives now being taken to standardize the measurement of this heterogeneous particle.
Appropriate design of biochemistry request cards can promote the use of protocols and reduce unnecessary investigations
Authors: Barth J H , Balen A H , Jennings A
Published: October 2002

Attempts to control laboratory workload in the past always proved to be short-lived. We designed a request card based on clinical conditions for a gynaecology out-patient clinic to help clinical staff to adhere to agreed investigation protocols. Each request card had a tick-box associated with a clinical condition. The tests performed for each condition were advertised on a poster in the clinic.

The workload was assessed for a 2-year period before and after the introduction of these cards. The numbers of all endocrine tests, except progesterone and sex hormone binding globulin, fell by 19% ( P< 0·0001) whereas the clinical cases seen remained steady at 227 per month.

This report demonstrates that agreed protocols can be implemented but that a persistent aide-mémoire is necessary.
Endocrinology of gynaecomastia
Authors: Ismail A A A , Barth J H
Published: October 2002

Gynaecomastia is the most common disorder of the male breast. It can occur at any age, and for this reason laboratory investigations may be requested by clinicians from many specialties. Gynaecomastia may occur transiently in neonates. It may also occur transiently during puberty, when it is common and generally benign. It must, however, be regarded as unusual in prepubertal children and all young and middle-aged men. Although iatrogenic and benign gynaecomastia are common in the elderly, further investigations may still be justified since breast cancer or other neoplasm must be ruled out. Biochemical investigations, when warranted, are aimed at establishing an underlying cause. Endocrine investigations might include serum oestradiol (or oestrone if available), testosterone, luteinizing hormone, sex-hormone-binding globulin, human chorionic gonadotrophin, prolactin and thyroid function tests. In this review, the source and role of oestrogens in men, the androgen-oestrogen dynamics, the causes and clinical entities of gynaecomastia, and interpretation of laboratory tests are described.
Assessment of homocysteine as a cardiovascular risk factor in clinical practice
Authors: Clarke Robert , Stansbie David
Published: October 2002

Elevated plasma total homocysteine concentrations are a marker of vitamin deficiency and a risk factor for cardiovascular disease. It is possible that vitamin supplementation with folic acid and other B vitamins, which lower plasma homocysteine concentrations, may reduce the risk of cardiovascular disease. Large-scale clinical trials are currently underway to assess the homocysteine hypothesis of cardiovascular disease. Pending the outcome of such trials, measurement of plasma homocysteine concentrations in people at high risk of cardiovascular disease may help to identify patients who could benefit from more intensive treatment of classical cardiovascular risk factors. The introduction of immunoassays for homocysteine determination has made assessment of homocysteine status accessible to most routine hospital laboratories, and this review summarizes the evidence on why and how to assess homocysteine as a risk factor for cardiovascular disease in clinical practice.
Prostate specific antigen: biology, biochemistry and available commercial assays
Authors: Ward A Milford , Catto J W F , Hamdy F C
Published: October 2002

Prostate specific antigen (PSA) is the marker of choice in the management of prostate cancer. However, PSA is not a simple molecule, existing in the serum in five isoforms and a number of molecular configurations and complexes. The elucidation of the biochemistry of PSA has increased the potential use of the marker in the diagnosis of prostate malignancy.

This review summarizes the clinical use of PSA in the management of prostate disease and the assays available in the UK. Assay calibration in relation to the World Health Organization 1st International Standard for Prostate Specific Antigen (90:10) has increased conformity between the various commercial assay kits, and the non-equimolar kits have largely been superseded or withdrawn. Special reference is made to evaluations performed on behalf of the Medical Devices Agency of the Department of Health.
Current state of screening for Down's syndrome
Authors: Holding Stephen
Published: October 2002

Down's syndrome has an incidence of about 1·3 per 1000 births. Antenatal testing for this disorder on the basis of maternal age has been common practice (increasing age is associated with increasing risk of having an affected pregnancy). Since the late 1980s it has been possible to calculate a pregnancy-specific risk using maternal age and serum marker levels, but the absence of a national screening policy in the UK has resulted in a diversity of screening practice. Screening may take place in the first or second trimester of pregnancy, using maternal age in combination with up to six serum markers, with or without ultrasound markers. Additionally, some units offer the screen only to women in specific age groups. Risk and marker levels are affected by a number of factors for which adjustments in the calculation may be made. Laboratories offering screening must also establish robust monitoring and quality management systems to ensure continued confidence in the reported result. Current diagnostic techniques require the use of invasive procedures which pose a risk to the fetus and the mother. Future screening may combine new technologies with the identification of fetal cells in maternal blood to reduce or abolish the need for these procedures.