Control of DNA synthesis genes in budding yeast: involvement of the transcriptional modulator MOT1 in the expression of the DNA polymerase alpha gene. Periodic transcription during the cell cycle of the budding yeast DNA polymerase alpha gene (POL1) requires the cis-acting element 5' ACGCGT 3', which has been found in the 5' non-coding region of all the DNA synthesis genes analyzed so far. Search for trans-acting mutations affecting POL1 expression led to the isolation of the temperature-sensitive reg1033 mutant, that showed increased levels of both DNA polymerase alpha and delta gene transcripts. Cloning of the REG1033 gene demonstrated that it is essential for cell viability and required for proper expression of the POL1 gene. DNA sequence comparison established that the REG1033 gene is identical to MOT1, a gene encoding a presumptive DNA helicase which modulates transcription of several yeast genes.


Protein affinity chromatography reveals cell cycle dependent association of cellular factors with human DNA polymerase alpha. DNA polymerase alpha/primase (Pol alpha) is the key replication enzyme in eukaryotic cells. This enzyme synthesizes and elongates short RNA primers at an unwound origin of replication. Pol alpha was used as an affinity ligand to identify cellular replication factors interacting with it. Protein complexes between Pol alpha and cellular factors were analyzed by co-immunoprecipitations with monoclonal antibodies directed against Pol alpha and by protein affinity chromatography of cell extracts derived from pure G1- and S-phase cell populations on Pol alpha affinity columns. Co-immunoprecipitations resulted in the identification of a polypeptide with a molecular weight of 46 kDa. For Pol alpha affinity chromatography, the ligand was purified from insect cells infected with a recombinant baculovirus encoding the catalytic subunit (p180) of Pol alpha (Copeland and Wang, 1991). With 5 x 10(8) infected Sf9 cells, a rapid one step purification protocol was used which yielded in five hours 0.6 mg pure enzyme with a specific activity of 140,000 units/mg. The G1- and S-phase cell populations were generated by block, release and counterflow centrifugal elutriation of exponentially growing human MANCA cells. Starting with 2 x 10(9) non synchronous cells, 5 x 10(8) G1-phase cells were isolated. Chromatography of cell extracts derived from G1- or S-phase cells on Pol alpha affinity columns resulted in identifying several polypeptides in the range of 40-70 kDa. Some of these polypeptides are more abundant in eluates derived from S-phase extracts than from G1-phase extracts.


Structural and functional relationships of human DNA polymerases. A continuing theme of our laboratory has been the understanding of human DNA polymerases at the structural level. We have purified DNA polymerases delta, epsilon and alpha from human placenta. Monoclonal antibodies to these polymerases were isolated and used as tools to study their immunochemical relationships. These studies have shown that while DNA polymerases delta, epsilon and alpha are discrete proteins, they must share common structural features by virtue of the ability of several of our monoclonal antibodies to exhibit cross-reactivity. A second approach we have taken is the molecular cloning of human DNA polymerase delta and epsilon. We have cloned the DNA polymerase delta cDNA, and this has allowed us to compare its primary structure to those of human polymerase alpha and other members of this polymerase family. Multiple sequence alignments have revealed that human DNA polymerase delta is also closely related to the herpes virus family of DNA polymerases. In situ hybridization has shown that the human DNA polymerase delta gene is localized to chromosome 19 q13.3-q13.4. In order to further determine the functional regions of the DNA polymerase delta structure we are currently expressing human pol delta in E. coli and baculovirus systems. Other work in our laboratory is directed toward examining the expression of DNA polymerase delta during the cell cycle.


Expression of the catalytic subunits of pol alpha and pol delta from fission yeast Schizosaccharomyces pombe. This paper reports on expression and posttranslational modifications of the catalytic subunits of pol alpha and pol delta from fission yeast Schizosaccharomyces pombe. Okadaic acid treatment of S. pombe spheroplasts in amounts known to inhibit phosphatases 1 and 2A resulted in decreased proteolysis of both pol alpha and pol delta. Computer analysis of pol alpha and pol delta sequences confirmed the presence of consensus motifs for protein phosphorylation. Indirect immunofluorescence microscopy of S. pombe cells showed nuclear location of both proteins in wild type cells. However, whereas cells transformed with a vector expressing pol alpha produced a clear increase of the nuclear signal, no increase was detectable in cells transformed with pol delta. This observation suggests the existence of a mechanism limiting the cell concentration of pol delta in the cell. Constitutive expression of S. pombe pol delta in E. coli was possible only with vectors containing truncated forms of its gene, indicating a toxic effect of pol delta on E. coli growth.


Use of non-denaturing Southern hybridization and two dimensional agarose gels to detect putative intermediates in telomere replication in Saccharomyces cerevisiae. Telomeres are required for the complete duplication of the ends of linear chromosomes. Saccharomyces telomeres bear approximately 350 bps of C1-3A/TG1-3 sequences. Previous work using non-denaturing Southern blotting has demonstrated the cell cycle controlled appearance of single stranded TG1-3 tails on chromosomal and plasmid telomeres (Wellinger et al. submitted). Furthermore it was shown that short linear plasmids carrying an origin of replication derived from 2 microns DNA can circularize at the time of telomere replication (Wellinger et al. submitted). Here we demonstrate that those loci previously shown to acquire single stranded tails are indeed telomeres and that single stranded TG1-3 cannot be observed in non-telomeric C1-3A/TG1-3-tracts. Moreover, we demonstrate that the formation of circular DNA by short linear plasmids is not restricted to plasmids containing a 2 microns origin of replication but can also be detected for plasmids containing ARS1.


Replisome pausing in mutagenesis.

Replisome pausing in mutagenesis. E. coli cells containing a temperature-sensitive dnaE mutation, in the alpha-subunit of holoenzyme DNA polymerase III, do not survive at the restrictive temperature. Such cells may survive in the presence of the pcbA1 mutation, an allele of the gyrB gene. Such survival is dependent on an active DNA polymerase I. Evidence indicates that DNA polymerase I interacts directly in the replisome (REP.A). Despite normal survival for cells using the pcbA replication pathway after some type of DNA damage, we have noted a failure of damage-induced mutagenesis. Here we present evidence supporting a model of replisome pausing in cells dependent upon the pcbA replication pathway. The model argues that the (REP.A) complex pauses longer at the site of the lesion, allowing excision repair to occur completely. In the normal replication pathway (REP.E) bypass of the lesion occurs, fixing the mutation.


Initiation of replication in the Chinese hamster dihydrofolate reductase domain. Two-dimensional (2-D) gel analysis of replication intermediates in the Chinese hamster dihydrofolate reductase domain has suggested that nascent chains can initiate at any of a large number of sites scattered throughout a approximately 50 kb "initiation locus" (although the level of initiation detected at any given site within this region was relatively low). This result contrasts markedly with data from an in vitro strand switching assay suggesting that > 80% of initiations occur within a single 500 bp fragment lying within the initiation locus. In an effort to reconcile these two disparate views of the initiation reaction, we have questioned the validity of our 2-D gel data in several ways. We show here that: 1) the number of replication bubbles detected in the DHFR locus in the early S period is markedly increased when the cells are released from a synchronizing agent that inhibits initiation per se, rather than from aphidicolin, which is a chain elongation inhibitor; 2) initiation in the DHFR domain occurs only during the first 90 min of the S period, as would be expected of an early-firing origin; 3) a pulse of 3H-thymidine moves through the structures observed on 2-D gels with the kinetics expected of bonafide replication intermediates; and 4) preparations of replication intermediates that are subsequently analyzed on 2-D gels appear, by electron microscopy, to represent the typical theta structures and single-forked molecules expected of bidirectional origins of replication; no unusual structures (e.g., microbubbles) were seen.


A human DNA replication origin: localization and transcriptional characterization. A single-copy 13.7 kb human DNA region (L30E) located on Ch. 19 p13.3 contains an origin of DNA replication in myeloid HL-60 cells. The origin was localized, by means of quantitative PCR within approximately 3000 bp, in a highly transcribed region containing at least two closely spaced genes with the same polarity of transcription, one encoding lamin B2 and the other an unidentified protein. The origin region overlaps an undermethylated "CpG island" at the 5'-end of the second transcription unit. A binding site (CACGTG) for basic helix-loop-helix (bHLH) DNA binding proteins such as USF/MLTF or MYC-MAX was located by DNase I footprinting analysis in the promoter of the second gene. DMSO differentiation of HL-60 cells, that completely shuts off replication, also drastically reduces the transcription of L30E region. On the other hand such treatment does not modify the methylation pattern of the CpG island and does not abolish the DNase I protection of the bHLH binding site.


Structural and functional studies on phi 29 DNA polymerase. The Bacillus subtilis phage phi 29 DNA polymerase, involved in protein-primed viral DNA replication, contains several amino acid consensus sequences common to other eukaryotic-type DNA polymerases. Using site-directed mutagenesis, we have studied the functional significance of a C-terminal conserved region, represented by the Lys-X-Tyr ("K-Y") motif. Single point mutants have been constructed and the corresponding proteins have been overproduced and characterized. Measurements of the activity of the mutant proteins indicated that the invariant Lys and Tyr residues play a critical role in DNA polymerization. Interestingly, substitution of the invariant Lys either by Arg or Thr, produced enzymes with an increased or a largely reduced, respectively, capability to use a protein as primer, an intrinsic property of TP-priming DNA polymerases. On the other hand, the viral protein p6, which stimulates initiation of phi 29 DNA replication by formation of a nucleoprotein complex at both DNA replication origins, increased (about 5-fold) the insertion fidelity of phi 29 DNA polymerase during the formation of the TP-dAMP initiation complex. We propose a model in which the special strategy to maintain the integrity of the phi 29 DNA ends, by means of a "sliding-back" mechanism, could also contribute to increase the fidelity of phi 29 DNA replication.


Adenovirus DNA replication: the function of the covalently bound terminal protein. Initiation of Adenovirus DNA replication in vitro requires the presence of three viral proteins (pTP, pol, DBP) and two cellular transcription factors, NFI and Oct-1, that stimulate replication more than 100-fold. NFI assists in binding and positioning of the DNA polymerase in the origin whereas Oct-1 changes the structure of origin DNA. Optimal templates contain, in addition to origin sequences, the covalently bound viral terminal protein (TP). This terminal protein stimulates the template activity over 20 fold compared to protein-free templates. To study the way in which TP exerts its function in vitro we devised a novel method to isolate and label a short origin containing fragment in which the TP was bound in a functional form. This fragment replicated very efficiently and could be used for studying the binding of other replication proteins. Employing alpha-chymotrypsin digestion we show that for enhancement of replication in vitro only a small part of TP is required.


Identification and characterization of a complex chromosomal replication origin in Schizosaccharomyces pombe. In the budding yeast, S. cerevisiae, two-dimensional (2D) gel electrophoresis techniques permit mapping of DNA replication origins to short stretches of DNA (+/- 300 bp). In contrast, in mammalian cells and Drosophila, 2D gel techniques do not permit precise origin localization; the results have been interpreted to suggest that replication initiates in broad zones (several kbp or more). However, alternative techniques (replication timing, nascent strand polarity analysis, nascent strand size analysis) suggest that mammalian origins can be mapped to short DNA stretches, just like S. cerevisiae origins. Because the fission yeast, Schizosaccharomyces pombe, resembles higher organisms in several ways to a greater extent than does S. cerevisiae, we thought that S. pombe replication origins might prove to resemble--and thus be helpful models for--animal cell origins. An attempt to test this possibility using 2D gel techniques resulted in identification of a replication origin near the ura4 gene on chromosome III of S. pombe. The 2D gel patterns produced by this S. pombe origin indeed resemble the patterns produced by animal cell origins and show that the S. pombe origin cannot be precisely located. The data suggest an initiation zone of 3-5 kbp. Some aspects of the 2D gel patterns detected at the S. pombe origin cannot be explained by the rationale of initiation in broad zones, suggesting that future biochemical and genetic studies of this complex origin are likely to provide information useful in helping to understand the apparent conflict between the 2D gel mapping techniques and other mapping techniques at animal cell origins.


Characterization of vaccinia virus DNA replication mutants with lesions in the D5 gene. The vaccinia virus D5 gene encodes a 90 kDa early protein that is essential for viral DNA replication. In this report we map and explore the phenotypes of the temperature sensitive mutants bearing lesions in this gene: ts17, ts24, ts69 (WR strain) and ts6389 (IHD strain). Viral DNA synthesis was virtually undetectable during non-permissive infections performed with ts17, and incorporation of 3H-thymidine ceased rapidly when cultures were shifted to the non-permissive temperature in the midst of replication. The D5 protein may therefore be involved in DNA synthesis at the replication fork. The lesions of the four mutants were localized within the D5 orf by marker rescue, and the single nucleotide changes responsible for the ts phenotype of the three WR mutants were identified. Unexpectedly, the three alleles with N-terminal mutations were impaired in marker rescue when homologous recombination with small (< 2 kb), intragenic DNA fragments at 39.5 degrees C was required. This deficiency was not due to degradation of transfected DNA under non-permissive conditions. Efficient marker rescue could be restored by incubation at the permissive temperature for a brief period after transfection, suggesting a requirement for functional D5 in genome/plasmid recombination. Marker rescue under non-permissive conditions could alternatively be restored by co-transfection of unlinked but contiguous DNA sequences.


[Hereditary motor and sensory neuropathy]. The report consisted of 10 cases of hereditary motor and sensory neuropathy (HMSN). There were 7 males and 3 females. Their ages ranged from 11 to 42 (average 24.6) years, ages of onset varied from 7 to 34 (average 17.3) years. Hereditary history was showed in 4 cases. The clinical features of all 10 cases had peroneal muscular atrophy, 8 of 10 cases also had involvement of the upper limbs, 7 of 10 cases had pes arcuatus. The conduction velocity was obviously slow in 5 cases and slightly slow in the others. Oion-bulb hypertrophic neuropathy was demonstrated in sural nerve biopsies of 5 cases. Neuronal axonal degeneration were found in the remaining 5 cases. Clinical classification, clinical features and pathological characteristics were discussed.


[A study on middle cerebral artery territory infarction with transcranial Doppler sonography]. The transcranial Doppler sonographic findings of 40 patients with middle cerebral artery (MCA) territory infarction were compared with those of 40 controls. The results showed that in the group of acute phase patients there was a large reduction of MCA mean flow velocity (Vm) of the infarcted side compared with the normal hemisphere (P < 0.01) and controls (P < 0.05). At the same time the anterior cerebral artery (ACA) Vm rose on both sides (esp. on the infarcted side) in comparison with controls (P < 0.05). The posterior cerebral artery (PCA) Vm did not change significantly (P > 0.05). In the group of chronic phase patients there were changes similar to the group of acute phase patients in MCA Vm and ACA Vm, but not statistically significant. Follow-up TCD examinations were carried out in 8 cases during the acute phase of stroke. We found that the decreased MCA Vm on the infarcted side returned to normal in 4 cases, remained lower in another 2 cases within 4 weeks after onset. The increased MCA Vm on the infarcted side in 2 cases returned to normal within 2 weeks after onset. Various types of TCD findings in patients with MCA occlusion were described and analysed.


[The diagnostic value of magnetic resonance imaging on neuromuscular diseases]. The article concentrated on the study of skeletal muscles of four extremities in 12 cases of different kinds of neuromuscular diseases and 4 volunteers with MRI. The results revealed: MRI could clearly display individual muscle, muscle groups or abnormal muscles morphologically. It could also demonstrate the difference between the neurogenic and myogenic changes. In patients with progressive muscular dystrophy (PMD), the gracilis m. and sartorius m. were relatively intact. In patients with primary myopathies, the severity of MRI changes was consistent with the severity of the illness and the EMG changes. The results indicated that MRI examination was helpful in the diagnosis of neuromuscular disorders. It can define the distribution and the severity of impaired muscles. In addition, MRI could be used to select the appropriate muscles for EMG examinations or muscle biopsies. Selective muscular impairments might be the characteristics of patients with PMD.


[A study of muscle fibers typing on Duchenne muscular dystrophy]. Quantitative analysis of muscle fibers typing in 15 cases of Duchenne muscular dystrophy has been done. Mean diameter, area, variability coefficient were estimated by computer. The results show that type IIC fibers were remarkably increased and type IIB fibers was deficiency in DMD. Atrophy and hypertrophy occurred in different typing fibers. The results indicated that DMD has a prominent atrophy and hypertrophy and active regenerating process.


[A clinicopathological study of neuronal ceroid lipofuscinosis]. 4 unrelated patients with infantile type (one case), late infantile type (one case), juvenile type (two case) of neuronal ceroid-lipofuscinosis were reported. The pathological study by brain biopsy was carried out with light and electron microscopes as well as histochemical methods. Ultrastructurally, the infantile type showed deposits of lipofuscin bodies, fingerprint bodies, and the late infantile type showed a lot of curvilinear bodies and paracrystalline bodies. The ultrastructural configuration in the juvenile type is more heterogeneous and consisted of combination of lipofuscin bodies, fingerprint bodies and multilamellar structures. It was emphasized that fingerprint bodies were first discovered in infantile type, which might challenge the view that only lipofuscin bodies can be found in infantile type.


[ELISA for detection of anti-filamin antibody in sera from patient with myasthenia gravis]. The activity of anti-filamin antibody was determined in sera from 128 patients with myasthenia gravis (MG) by enzyme-linked immunosorbent assay (ELISA). The positive rate was 77.34%. No correlation was observed between anti-F-ab and nAchRab and CAEab. The antibody-absorbtion test were positive. The result demonstrated that anti-F-ab may play some role in the pathology of MG. The clinical use of ELISA for detection of anti-F-ab may help to diagnose MG.


[A case-control study of risk factors on Alzheimer's disease. Multicenter collaborative study in China]. A case control study to assess the possible risk factors associated with Alzheimer's disease (AD) among Chinese population was conducted on 126 clinical diagnosed AD patients and 252 matched by sex, age, nationality non-demand neighborhood as control. Factors significantly associated with AD cases were: family history of dementia in first degree relatives, family history of psychoses in first degree relatives, few interests and heavy negative life events during individual's life time. Neither family history of Down's syndrome, antecedent history of head trauma, nor other condition that might support immune hypotheses were significantly associated with AD cases. The data from this study support the familial/genetic hypotheses of AD and also the role of psychosocial factors in AD.


[Preliminary study of changes in plasma prostaglandin E1 in rats with experimental "schizophrenia"]. We referred to Borison's method of making the model schizophrenia. Rats were injected d-amphetamine intraperitoneally once a day so that the schizophrenia models were established within four weeks. After five weeks, rats with schizophrenia were treated with chlorpromazine. Contents of plasma prostaglandin E1(PGE1) in rats were determined before and after treatment respectively. This study demonstrated that contents of plasma PGE1 in rats receiving amphetamine for four weeks were higher than those in control animals (P < 0.05). At this time, male rats' stereotypy scores were 3.5 and female stereotypy scores 5. But contents of plasma PGE1 in rats with schizophrenia approached those in control animals with giving amphetamine once a day continuously. Contents of plasma PGE1 decreased in rats with schizophrenia receiving chlorpromazine.


[Distribution of common symptoms in 2500 schizophrenics and their comparative analysis on the background of times and culture]. In the paper, the distribution of the common symptoms in 2,500 Schizophrenics was reported, including 1,600 cases in Shanghai Mental Health Center, 500 cases in Chuan Sha County Mental Hospital, 200 cases in Nan Hui County Mental Hospital in Shanghai and 200 cases in Su County Mental Hospital in An Hui province respectively. In the 2,500 cases, apart from 1,600 cases including 500 cases discharged from 1964 to 1965, and 500 cases discharged from 1984 to 1985 in Shanghai Mental Health Center, the rest was hospitalizing during 1988 to august of 1990. Among these patients, 67 symptoms were shown in which 47 symptoms were much common. There was the most significant difference in the 22 symptoms of the 23 much more common symptoms between 1960 and 1980s (P < 0.01). According to the comparison of the various cultural background, there was the most significant difference in 15 symptoms (P < 0.01).


[Predicting the effects of haloperidol on schizophrenics by quantitative pharmaco-EEG]. In order to predict the short-term-outcome of schizophrenics under the treatment of haloperidol, changes of 15 schizophrenic subjects' EEG after 4 mg haloperidol oral intake were monitored with the method of QPEEG. The result of discriminate analysis showed that the more similar to typical EEG pattern of neuroleptics the patients showed, the better the patients responded to haloperidol treatment. Meanwhile, the haloperidol therapeutic mechanisms of brain electro-physiology and the electro-physiological characteristics of schizophrenics were also discussed.


[A study on effects of parents age, birth order and mental retardation of unknown etiology]. On this report 461 matched cases of mental retardation of unknown aetiology were analysed on the relationship between the diseases and the parents age, birth orders with conditional Logistic regression. These cases were accurately diagnosed and selected from the Epidemiologic Survey of genetic diseases of Sichuan, China. The results found that mental retardation of unknown aetiology is related to the age of parents and birth order. The paternal age is the main factor while the maternal age in not a significant effect and birth order also in not a significant effect after readjusting the other factors. Compared to paternal age group of under 25. There are significant increase of relative risks of age group 30-34 and 45 above, about 1.8 and 2.7 fold increase in univariate analysis and 1.9 and 3.3 fold increase in controlling the maternal age and birth order, a chi-square test for trend of distribution of paternal age also indicates a significant dose response relationship between increasing risk with age. The significance of result and methods of analysis were discussed.


[Frequency of sex chromatin among mental patients]. The frequency of sex chromatin of 2000 cases of mental patients are observed in this paper. The frequency of Y chromatin in male and X chromatin in female was 28.01% and 26.86% respectively, whereas only 16.97% and 17.84% respectively in the control group. The mental patient group is higher than the control group significantly (P < 0.0001). It may be influenced by some psychotropic drugs and the factor of course. Positive X chromatin in the male patients was 8 cases and karyotypes of chromosome was XXY type all. The incidence of XXY type is 0.77% and significant higher than the control group (0.18%, P < 0.01). It suggested that ratio of add one X chromosome in the male mental patients be obviously increased. The authors indicated if this examination be routinely used in clinic that would prevent misdiagnosis and would raise accuracy of diagnosis.


[Computerized tomography findings and clinical analysis of psychiatric disorder of praecox from head injury. Report of 52 cases]. This article reports and analyses 52 cases of psychiatric disorders of praecox from head injury. These patients included 39 males and 13 females. They were 13-80 years old. All of them examples by CT scan and found intracerebral hematomas or cerebral contusion. The shortest course of disease was 3 day, and the longest course was 53 day. 44 cases (84.7%) appear psychiatric disorders in first week. The most frequent psychiatric symptoms was disturbances of consciousness and dysmnesia. Disturbance of emotion, change of personality were also observed. Frequency of psychiatric disorders was same in brain traumatic of left or right lateralis. Course of disease and degree of psychiatric symptoms had nothing to do with size of hematoma and cerebral contusion, and relate to compression of ventricles of the brain. Encephalo-edema around the focus leading to regional compression of the brain was important factors for the disorder. The appearance of this disorder was early, course of disease was short, and prognosis was good.


[Immunotherapy of human retinoblastoma with RGNTF-monoclonal antibody using nude mice as model]. Retinoblastoma in nude mice as an animal model was developed by injecting cultured human retinoblastoma cell line(Rb) Y79 into the anterior chamber of eyeball. It was treated by direct injection of RGNTF-McAb into the Rb tumor. Ten out of 30 eyeballs with Rb inoculation did not develop tumor (32% inhibition) if Rb cell suspension was mixed with the RGNTF-McAb before injection; whereas in the control, all 40 but 3 eyeballs developed tumor (7%) when Rb cell suspension alone had been injected. This 32% of inhibition of Rb tumor formation by RGNTF-McAb was very significant (T > 2.58, P < 0.01). The results of immunotherapy of 46 eyeballs with Rb tumor developed 10 days after inoculation by RGNTF-McAb for 2 months revealed that the proportion of grade III-IV tumors before and after therapy reduced from 53% to 26% and that of grade I-II tumors increased from 47% to 74%. Feulgen DNA staining of tumor sections after therapy revealed that the average DNA contents in Rb cells decreased significantly (P < 0.01) from 16.2 +/- 2.6 in grade III-IV to 5.3 +/- 1.2 in grade I-II compared to that of the untreated control 18.8 +/- 3.2. Numerous white cells infiltrating the Rb tumor, hyperplasia of fibrous tissues, and no spreading and metastasis of the tumor tissue were observed in the treated eyeballs; whereas Rb tumor was spreading to the optic nerve and superior colliculus in the untreated eyeballs. Therefore, the RGNTF-McAb can not only inhibit the growth of Rb cells but also limit their spreading and metastasis.(ABSTRACT TRUNCATED AT 250 WORDS)


[Biological characteristics of tumor growth delay in human nasopharyngeal carcinoma xenograft (NPC-837) after irradiation]. Tumor growth and cell cycle of human nasopharyngeal carcinoma xenograft in nude mice (NPC-837) after irradiation were studied. After cobalt-60 irradiation of 5.0Gy, 7.5Gy, 10Gy, 15Gy and 20Gy, the tumor volume was reduced to 80, 70, 50, 35 and 10 percent of the control, respectively. However, the tumors began to grow again. The time (in days) the tumors took to reach the volume of the control was radiation dose-dependent. With 20 Gy irradiation the tumor volume was kept at 10% of the control level for as long as 20 days before regrowth occurred, but it never reached the control level up to 108 days of observation. A mean G2 cell block rate of 1.21% after irradiation was observed and a G2 cell block was marked after 7.5Gy irradiation. The results indicate that NPC-837 is a very radiosensitive and valuable model for the radiobiological research of solid tumors.


[Effects of Se-enriched malt cakes on UV benzo(a)pyrene induced unscheduled DNA synthesis of lymphocytes from high risk population of lung cancer]. Se-malt cakes containing 300 micrograms selenium were given daily to men from high risk area of lung cancer and the influence of ultraviolet light (UV) and be benzo(a)pyrene (B(a)P) induced unscheduled DNA synthesis (UDS) of peripheral lymphocytes were determined. After Se-supplementation for 6 months, the Se levels in serum, hairs and activity of GSH-px were increased by 89%, 67% and 178%, respectively. The ratio of UV-induced UDS was decreased from the mean value of 2.47 in the control to 1.61 (P < 0.05) in the Se-group. After Se-intake for one year, the Se levels were elevated by 78% in serum, 83% in hairs and 56% in GSH-px activity, while the mean value of B alpha P-induced UDS was reduced from 2.21 in the control to 1.47 (P < 0.05) in the Se-group. The results of the present study indicate a blocking effect of Se-supplementation to UV- and B alpha P-induced UDS of peripheral lymphocytes from high risk subjects for lung cancer.


[Stable and efficient expression of human interleukin-6 cDNA in mammalian cells after gene transfer]. Following reverse transcription and PCR amplification, the human interleukin-6 (IL-6) cDNA was cloned from total RNA of activated human tonsillar mononuclear cells. Southern blot showed the presence of specific band, and its DNA sequence demonstrated that the fragment was 650 bp in length, spanning the complete coding region and part of 5' and 3'-untranslated regions. The human IL-6 sequence seemed to be well conserved. One nucleotide change at 429 position was observed, but this change did not affect the amino acid composition. After inserting the cloned cDNA into retroviral vector XM-6, the recombinant was packaged in PA317 cells and the amphotropic virus titer reached 5 x 10(5) CFU/ml. Human IL-6 was expressed in mammalian cell line SP2/0 cells, after being infected by the constructed retrovirus. The G418 resistant SP2/0 cells secreted IL-6. Its supernatant was able to maintain in vitro growth of the IL-6 dependent T1165 cell line. Northern blot analysis of the transfected SP2/0 cells showed significantly elevated IL-6 message, being consistent with the result of T 1165 bioassay. The expression was stable during the 12 month period of observation. The hybridoma cells, formed after fusion of the transfected SP2/0 cells and lymphocytes, exhibited accelerated growth.


[Diagnostic significance of multinuclear giant cells in lymph node fine needle aspiration]. Enlarged lymph nodes, commonly seen in inflammatory or tumorous conditions, is often suspected as Hodgkin's disease in cytologic diagnosis. Twenty cases originally diagnosed as Hodgkin's disease by fine needle aspiration of lymph nodes are reported. Eighteen of these 20 cases were checked by histopathology. It was found that only 3 had reached the correct diagnosis. The authors believe that by thorough understanding of the origin and characteristics of various types of multinuclear giant cells, differentiation from Hodgkin's disease is possible.


[Comparative pathologic study on the peri-ulcer mucosal lesion around benign and malignant gastric ulcer]. 3441 peri-ulcerous mucosal lesions around benign and malignant gastric ulcers (1479 benign gastric ulcers, 421 cancerous degeneration of benign ulcers and 1541 ulcerative carcinomas) were studied comparatively. It was found that the ulcer of cancerous degeneration of benign ulcer was small and the epithelial regeneration at the ulcer's edge and fusion of the muscularis mucosa with the muscularis propria were very common. The cancerous tissue, extending down to the submucosa, was found at the margin but not at the base of the ulcer. Lymph node metastasis was rare. Therefore, the cancerous degeneration of ulcer was most likely an early carcinoma. These findings conform well with Hauser's criteria. Chronic atrophic gastritis intestinal metaplasia (IIb and type II), moderate and severe dysplasia were more commonly observed in cancerous degeneration of ulcers than in benign peptic ulcers or ulcerative carcinoma. These results suggest that multiple biopsies should be taken from the edge of chronic ulcers.


[Intra-arterial digital subtraction angiography (IADSA) in liver metastases]. From Dec. 1988 to Dec. 1990, fifty cases of metastatic liver tumors were examined with IADSA. The present article analysed the DSA imaging in this series and divided the DSA appearances of the tumor vessels into five types: 1. Dilatation and enlargement, 29 cases (58%); 2. Stricture and narrowing, 17 cases (34%); 3. Zigzag and tangle, 39 cases (78%); 4. Intermittence and discontinuance, 20 cases (40%); 5. Removement and encirclement, 34 cases (68%). Sometimes several types could be found in one case. There were two cases in this group without any tumor vessels. The DSA appearances of tumor stains were also divided into four types: 1. Circular, cystiform and honeycomb-like, 9 cases (18%). 2. Nodular masses, 13 cases (26%). 3. Spots and flakes, 8 cases (16%). 4. Wadding-like, 15 cases (30%). There were 5 cases without any tumor stains. In no case there was AVM or cancerous embolus in portal vein. In this series, hypervascular lesions were observed in 17 cases (34%), midvascular lesions in 25 cases (50%), and hypovascular lesions in 8 cases (16%).


[Shortcomings of esophagogastric stapling device and their correction and prevention]. From 1985 to 1991, 202 patient with cancer of the esophagus or gastric cardia were resected with esophagogastric stapling device. The shortcomings were: 1. Necessity of second stapling-5 cases, and 2. Defective performance-9.1% (19/207 times) which was due to; a. failed coupling (7 times), b. incomplete resection (6 times), c. tearing of the muscular layer (4 times), d. gastric tube stapled into the stoma (1 time), and e. fall-off of thread from the purse-string suture at the esophageal stump (1 time). The correction procedures were: 1. Repair by hand suture (6 times), 2. Repeated stapling (5 times), 3. Repair of muscle tear by silk sutures (6 times), and 4. Second resection (2 times). Prevention of these shortcomings are discussed. The authors believe the stapling device can not replace manual suturing.


[Reconstruction of trachea, carina and bronchus for tumors of the trachea, carina and lung]. This paper reports on 70 patients with tumors of the trachea, bronchus and lung treated by reconstruction of the trachea, carina and the main bronchus (21 cases) and sleeve lobectomy (49 cases). Postoperatively, 2 patients died of tracheo-innominate artery fistula and 2 developed empyema which was healed. There was no mortality in the sleeve lobectomy patients. The 3- and 5-year survival rates of the cancer patients treated by reconstruction of trachea, carina and main bronchus were 54.5%(6/11) and 33.3%(3/9), respectively. The 3- and 5-year survival rates of lung cancer patients treated by sleeve lobectomy were 46.6% (14/30) and 33.3% (7/21), respectively.


[Surgical treatment of esophageal cancer in post-subtotal gastrectomy patients]. Among the 1285 cases of esophageal cancer operated in our hospital during the interval 1985-1990, 11 had had subtotal gastrectomy earlier, with an incidence of 0.86%. Among these 11 cases, two had upper thoracic segment lesions which were resected and reconstructed by transverse and descending colon transplantation into the neck. Right postero-lateral thoracotomy, upper abdominal and left neck incisions were used. Nine patients had esophageal cancer in the middle and lower thoracic segment and 7 of them were operated by transplanting the remaining stomach with spleen and caudal portion of pancreas into the left thorax and esophago-gastrectomy with the remaining stomach. Exploratory thoracotomy only was done in the other 2 patients. No complication occurred. Billroth type II gastrectomy was found to be easier than Billroth type I to move the remaining stomach together with the spleen and pancreas up into the thorax and to anastomose supra-aortically. There was no direct cause-effect evidence between gastrectomy and the site of esophageal cancer. The purpose for gastrectomy (ulcer or cancer) and the type of gastrectomy (Billroth type I or II) were irrelevant to the subsequent development of esophageal cancer.


[Combination of radiotherapy and surgery for advanced cancer of the vulva]. From 1970-1985, seventy-six patients with advanced carcinoma of the vulva were treated. It accounted for 58.9% of all vulvar cancers seen in the same interval. According to the revised FIGO Staging System of Vulvar Cancer, 64 had Stage III, and 12 had Stage IV lesions. Fourty-eight patients had tumor extending to the distal urethra, vagina or anus. Fifty-one were treated by radiotherapy combined with radical vulvectomy and inguinal lymphadenectomy, 10 by surgery alone, 9 by radiotherapy alone and 6 by palliative radiotherapy. In 20 (55.6%) patients the tumor was reduced > or = 50% and in 4 (20%) patients the tumor completely disappeared after pre-operative radiation as shown in pathologic examination of the resected specimens. The 5-year survival rate was 46.9% for Stage III, 33.3% for Stage IV disease, with an over-all 5-year survival of 60.8% on the combined group. Surgery alone gave a 5-year survival rate of 30%. All the patients died of cancer within 5 years in the radiotherapy and palliative radiation groups. It is suggested that combined radiotherapy and surgery be preferred for advanced cancer of the vulva. Technique of encompassing the vulvar and inguinal areas needs to further studied and improved.


[Photodynamic therapy in the treatment of carcinoma of the urinary bladder and prevention of its recurrence]. Sixty-eight patients with carcinoma of the urinary bladder were treated with photodynamic therapy (PDT). The results demonstrated that the tumors of 1-2 cm in diameter had best results, the tumors of 2-4 cm in diameter should be irradiated repeatedly or with intensified energy density, whereas those above 4 cm in diameter or those that had infiltrated deep muscular layer or neck of the bladder showed poor results. In this group, the total effective rate is 91%, the 5 year cure rate is 71.1%, and the 5 year recurrence rate is only 27.9%. In addition, we used preventive photodynamic irradiation of total bladder in 14 cases with bladder carcinoma who had undergone treatment. The 2 year recurrence rate was 7.1% (1 case), demonstrating a very promising result. The mechanism of tumor destruction with PDT action, the reasons for low recurrence rate, the advantages and disadvantages of this therapy were also discussed.


[Carcinoid tumors of the thymus--a report of 7 cases]. Carcinoid tumor of the thymus is rare and often clinically misdiagnosed as thymoma. However, those two types of tumors differ from each other greatly in their origin, biological behavior, accompanying syndromes, pathological features as well as prognosis. Seven cases of this tumor are presented here, which have had surgical intervention and pathological confirmation. Two of them were accompanied with Cushing's syndrome, another one was associated with pericarditis. Resection was accomplished in 5 cases and exploratory thoracotomy in 2 cases. Among the 7 cases, the two cases receiving exploratory thoracotomy died of tumor in its late stage. One patient died of widespread bone metastases 2 years after resection. One had tumor recurrence 3 years after original tumor resection and received another surgical operation. The characteristic features of carcinoid tumors of the thymus are diagnostic difficulty, potential malignancy, frequent recurrence and extrathoracic metastasis for prolonged period postoperatively. Histopathological, electron microscopic and immunohistochemistry examinations may be required in making an accurate pathological diagnosis. Thorough surgical excision of the primary and secondary tumors is of great importance in treatment.


[Advanced prostate cancer--an analysis of 17 cases]. Prostate cancer is a disease mostly effecting aged men. The incidence rate of this disease is much lower in China than in Europe and America. However, certain data have been accumulated indicating an increasing tendency in this country in recent years. The present report also supports this view and suggest the importance of strengthening of epidemiological research in this area in future. The problem how to treat patients with advanced prostate cancer is of essential importance since most cases are diagnosed in III or IV stage of the disease. In the present study, 10 out of 26 suspected cases (38.5%) was diagnosed by needle aspiration biopsy, being 90.9% of 11 cases confirmed histopathologically. The elevation of tumor maker acid phosphatase activity was positive in 8 out of 17 cases (47.1%). In this group, 11/17 (64.7%) received bilateral orchidectomy plus estrogenic hormones. The effective rate was 81.9% (9/11). Relapse occurred in 4 out of the 9 cases (44.4%), probably due to estrogenic hormone-dependence.


Dental materials for posterior restorations. Assessment of the quality of dental restorations by the Ryge system is described. Generally, the quality of dental restorations is shown to be dependent on the technique sensitivity of the restorative material as well as the skill and experience of the dentist. Concerning biocompatibility, adverse reactions related to amalgam restorations are unlikely or scarce, due to small amounts of released mercury. Resin based restorative materials contain a large number of organic compounds and, as such, the toxic and allergenic potentials are unknown. Gold and ceramics turn out to be the most biotolerable dental materials. Based on studies on longevity, data indicate that the median age of amalgam restorations is 10-12 years, of gold castings 13-14 years and more, and of composite restorations 4 years. Data on longevity of ceramic restorations are sparse. Secondary caries appears to be the most frequent cause for replacement of the different restorations, followed by marginal degradation. Secondary caries account for more failures among the resin based restorations than among amalgam. Reviewing the literature, it appears that amalgam is the best and most economic dental material for routine posterior restorations with reasonable durability. Gold is recommended for complex restorations. Resin based composites may be limited to small restorations where cosmetics is the main aspect, as wear and recurrent caries are main problems. Ceramic restorations comprise aesthetic restorations with excellent biocompatibility, however, data on longevity and marginal adaptation are not encouraging.


Digital subtraction radiography for assessment of simulated root resorption cavities. Performance of conventional and reverse contrast modes. A previous study of the sensitivity and accuracy of a standardized radiographic technique for the disclosure of root cavities in a cadaver material indicated that it was not possible to perceive small artificial "resorption" cavities. Using the same material, the aim of the present study was to evaluate whether the use of subtraction radiography would improve the detection of root cavities. In an autopsy material of five mandibular blocks each containing two premolars, small, medium, and large cavities were drilled in the cervical, middle, and apical thirds of the proximal and oral root surfaces. Each jaw block was radiographed before (B) and after (A) cavity preparation with three different exposure times resulting in light, medium, and dark film densities. The radiographs were digitized. Digital subtraction was performed between the A- and B images of varying densities by a computer program developed for dental subtraction radiography. Conventional and reverse contrast modes of the subtraction image were assessed independently by four observers. The results showed small inter- and intraobserver differences in diagnostic accuracy for assessment of total number of root cavities. Original film density did not influence the diagnostic performance in the resulting subtraction image. Contrast mode in the subtraction image influenced diagnostic performance as the majority of observers did best with the reverse contrast mode (p < 0.05). Some of the small root cavities were disclosed by the subtraction technique, but overall accuracy was not increased compared to conventional radiography.


Exposure of dental personnel to chloroform in root-filling procedures. The exposure of dental personnel to chloroform in root-filling procedures was evaluated. Four different root filling procedures were studied. In all the procedures studied, guttapercha was used as the root-filling material and chloroform or sealers containing chloroform were used. Ten teeth in each group were root-filled. In the first group, chloroform and 5% rosin in chloroform were administered in medical cups, in the second group chloroform and Kloroperka NO was administered in medical cups. In Group three a specially designed glass tube (S-endodip) was used for administration and in the fourth group specially selected plastic tubes were used. In the last two groups the sealers were chloroform and 5% rosin in chloroform. When medical cups were used the exposure reached levels close to the accepted limit values in Sweden, indicating that only one root filling per day can be performed without the dental team being unacceptably exposed. Using either the glass tube or the specially designed plastic tube, the exposure was significantly reduced for the dentist (p < 0.005) and for the nurse (p < 0.005). The mean exposure was 19.1 mg/m3 for the dentist and 11.6 mg/m3 for the nurse in the first experimental group. The mean values in the second group were 15.4 mg/m3 and 16.6 mg/m3 respectively. In the third group, the dentist was exposed to a mean of 4.4 mg/m3 and the nurse to 6.3 mg/m3. In the fourth group, the mean exposure was 2.2 mg/m3 and 3.4 mg/m3 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


Lay and professional knowledge of methods for emergency management of avulsed teeth. Proper treatment during the first 30 minutes offers the best prognosis for traumatically avulsed teeth. This study sought to determine both lay people's and dental professionals' knowledge of and attitude to emergency procedures. A 12-question survey was administered to 5 groups: (a) parents of learner swimmers and (b) coaches of college sports teams (lay); (c) State Dental Nurses, (d) dentists and (e) dental nurse/receptionists (professional). Respondents totalled 184 (a 32, b 86, c 24, d 18, e 24) i.e. 118 lay and 66 professional. Data revealed that group b had the greatest personal experience of avulsed teeth and groups c and e the least. Public hospital accident and emergency services (A & E) were perceived by all groups as most available. 18% of lay groups could not cite an emergency service. Lay people thought first of A & E for management whereas profession groups preferred the victim's own dentist. Most professional people would replant avulsed permanent teeth and about 1/3 would replant deciduous teeth: 1/2 lay people would replant permanent teeth and 1/8 deciduous teeth. Where treatment was not straightforward lay people would seek advice before acting. Half of the lay groups would transport an avulsed tooth dry. All the professionals had had advice on management of avulsed teeth but only 1/4 of the lay groups. This study highlighted the need for educational campaigns aimed at members of the lay public likely to be involved in the emergency management of traumatically avulsed teeth.


Comparative immunohistochemical identification and relative distribution of immunocompetent cells in sections of frozen or formalin-fixed tissue from human periapical inflammatory lesions. The presence of immunocompetent cells (B, Th/i and Ts/c cells and macrophages) and the ratios of these cell populations in periapical lesions (radicular granulomas, radicular cysts and apical scars) were demonstrated immunohistochemically using paraffin and cryo-sections. Thirty-four human periapical lesions were examined for the presence of immunocompetent cells by monoclonal antibodies and the biotin-avidin-horseradish peroxidase method. The T/B cell ratio of radicular cysts was significantly higher than that of both radicular granulomas and apical scars, and the average number of Th/i cells was greater than that of Ts/c cells in the radicular granulomas. However, no significant difference was found between radicular cyst and apical scar. The number of macrophages in radicular granulomas was significantly higher than that of the other lesions. These findings suggested that periapical lesions develop as a result of both humoral and cell-mediated immunological response and indicated that the ratios of immunocompetent cells are different in the different types of periapical lesion.


Traumatic bone cyst: case report.

Traumatic bone cyst: case report. The traumatic bone cyst is a lesion whose aetiology and pathogenesis have not been conclusively established. There are several theories and names for this lesion and various forms of management have been reported in the literature. This report outlines the clinical and radiographic findings associated with a case of a traumatic bone cyst. Laboratory investigations were also carried out and their findings are reported. This case was treated jointly by the endodontic and oral surgery departments of an institution and demonstrates the need for close follow-up from both departments. In particular, the endodontic aspects of monitoring the pulp status of teeth in the region of such a bone lesion are emphasised.


Emergency dental management of a patient with von Willebrand's disease. A patient with von Willebrand's disease presenting for dental treatment requires thorough evaluation prior to the determination of a proper course of treatment. In this case report, a patient with von Willebrand's disease presented to the emergency room with dental trauma. A modified treatment plan, taking into account the severity of the patient's systemic illness and the need for medical management, yielded successful results.


An international multicenter study of blood culture practices. The International Collaborative Blood Culture Study Group. An international study was organized to review blood culture practices in 67 medical centers, most of which were teaching hospitals with a total of over 58,000 active hospital beds. The number of blood cultures per admission was generally greater than 0.5 in the USA and less than 0.5 in other countries. Criteria varied for defining a septic episode, as well as for ascribing clinical importance to isolates of coagulase-negative staphylococci; however, septicemia rates tended to be lower in centers in which clinical evaluation was included among these criteria. Staphylococci were ranked first or second among etiologic agents of septicemia in the USA, whereas Escherichia coli was most frequently ranked first among European and Asian centers. All USA centers recommended collection of two blood cultures per septic episode and all but one recommended a maximum number of blood cultures per septic episode, whereas similar recommendations were less common in Europe and Asia. Collection of more than 10 ml per blood culture was more common in the USA than in Europe or Asia. A variety of broth-based systems were used, often in combination with lysis-centrifugation for special (fungal, mycobacterial) or, on occasion, routine purposes.


Clindamycin versus phenoxymethylpenicillin in the treatment of acute orofacial infections. The efficacy of clindamycin and phenoxymethylpenicillin in the treatment of orofacial infections was compared in a randomised study in 60 patients: 30 patients received clindamycin 150 mg every 6 h for seven days, and 30 received phenoxymethylpenicillin 1 g every 12 h for seven days. Where indicated incision and drainage were carried out. All patients but one in each group responded satisfactorily to treatment. Although the clindamycin group had a shorter duration of pain, swelling and fever and more favourable laboratory findings, the differences between the groups were not statistically significant. Of the 60 microbiological specimens 23 yielded only anaerobic bacteria, 34 both anaerobic and aerobic bacteria, two aerobic bacteria only and one no growth. In the penicillin group one case of severe diarrhoea occurred, and six patients in the clindamycin group had moderate to severe gastrointestinal discomfort, including one case of Clostridium difficile associated diarrhoea. This difference was however not statistically significant. The results support the continued use of penicillin for treatment of orofacial infections, with clindamycin serving as an effective alternative.


Virulence properties of erysipelas-associated group A streptococci. Group A streptococcal isolates (n = 53) recovered from 38 erysipelas patients in 1988 and 1990 in Sweden were analysed with respect to serotype, erythrogenic toxin production and polymorphism in the emm gene region. Serotype determination showed a dominance of type T1M1 (28.6% of the strains), but T type 8 was also prevalent (14.3%). In the majority of the strains only a low production of erythrogenic toxin A was demonstrated, while both toxin B and C production were high. Polymorphism was detected in the emm gene region of T1M1 strains at a frequency of 64%. These erysipelas associated group A streptococci were more heterogenic with respect to serotype distribution and polymorphism in the emm gene region compared to previously studied group A streptococci isolated during an outbreak of serious streptococcal infections in Sweden in 1988/1989. The material included isolates from two cases of recurrence, and typing of the isolates indicated that the patients had been infected by the same serotype as in the primary infection.


Underestimation of the incidence of measles in a population of French children. Data on titres of specific antibodies against measles virus and information given by families and physicians were analysed in 133 vaccinated and 117 unvaccinated children. Only 2 of the 133 vaccinated children reported a history of measles, while 131 had detectable levels of antibodies. Measles antibodies were detected in 102 (87.2%) of the unvaccinated children, but a history of measles diagnosed clinically by a physician was reported in only 42 of them. These findings suggest that subclinical cases of measles are possible and contribute to the high circulation of the measles virus in the child population in France.


Fatal necrotizing esophagitis due to Penicillium chrysogenum in a patient with acquired immunodeficiency syndrome. Although blue-green molds of the genus Penicillium are ubiquitous in the human environment, invasive penicilliosis is uncommon and primarily encountered among immunosuppressed patients. A patient with HIV infection who died of severe necrotizing esophagitis caused by Penicillium chrysogenum is reported and the relevant English language literature on human penicilliosis is reviewed. Although infectious esophagitis is commonly associated with AIDS, Penicillium esophagitis has not been described in such patients.


Three cases of infection with Fusarium species in neutropenic patients. Three cases are reported of disseminated infection due to Fusarium species in severely neutropenic patients. The clinical findings in all patients included fever, painful disseminated nodular skin lesions and severe myalgia. The outcome was fatal despite early administration of amphotericin B. The portal of entry of the organism was probably the nasal sinus in two cases.


Emergence of resistance to erythromycin and fluoroquinolones in thermotolerant Campylobacter strains isolated from feces 1987-1991. During the period 1987 to 1991 a retrospective study was performed to determine the resistance of thermotolerant Campylobacter species isolated from feces to erythromycin and fluoroquinolones. Of the 672 strains studied, 614 (91.3%) were identified as Campylobacter jejuni and 58 (8.7%) as Campylobacter coli. During the study period the rate of resistance of Campylobacter jejuni to erythromycin remained relatively stable (0.9-3.5%), while resistance of Campylobacter coli to erythromycin emerged later (1989) with much higher rates (14.8-33%). Overall, 11.8% and 10.7% of Campylobacter jejuni strains isolated after 1987 were resistant to nalidixic acid and ciprofloxacin respectively, resistance increasing from 2.3% in 1988 to 32% in 1991. In 1991 the first strains of Campylobacter coli with resistance to these fluoroquinolones were detected (rates 29% and 26% respectively). Of the strains resistant to nalidixic acid, only 10.9% were susceptible to ciprofloxacin.


In vitro antibacterial activity of antiseptics against vaginal lactobacilli. The results of investigations carried out to evaluate the inhibitory activity in vitro of seven vaginal antiseptic douche solutions against several strains of vaginal lactobacilli isolated from asymptomatic women are reported. Some of the products examined showed marked antibacterial activity even at high dilutions and for short exposure times. The post-antibiotic effect of two of these antiseptics on vaginal lactobacilli was also evaluated. The results of these investigations suggest that uncontrolled use of antiseptic products could cause changes in the normal vaginal flora.


Comparison of the E test and a reference agar dilution method for susceptibility testing of anaerobic bacteria. The susceptibility of 146 recent clinical isolates of gram-negative and gram-positive anaerobes was determined by the E test (AB Biodisk) on both Wilkins-Chalgren and PDM ASM II (AB Biodisk) agar. Results of the E test were compared with results obtained by the NCCLS agar dilution method using Wilkins-Chalgren agar. Incubation was for 20 hours and 44 hours in the E test and for 44 hours in the NCCLS method. In general, 44 hour results were more reliable; however, NCCLS readings were made only once after 44 hours. After two days of incubation, 91% of E test results on Wilkins-Chalgren agar were within one dilution and 98% within two dilutions of the corresponding NCCLS values; on PDM agar these values were 89% and 98%, respectively. Major and very major discrepancies combined were less than 1%.


Comparative evaluation of the MB-Check system for recovery of mycobacteria from clinical specimens. The performance of the MB-Check system (Roche) in the recovery of mycobacteria from clinical specimens was compared with that of the Bactec radiometric system and conventional culture on Löwenstein-Jensen medium. A total of 1,582 clinical specimens were used for the study; 74 yielded mycobacteria. Organisms of the Mycobacterium tuberculosis and Mycobacterium avium complexes accounted for the majority of isolates. The rate of recovery of all mycobacteria with the Bactec system was 91.9%, with the MB-Check system 79.7% and on Löwenstein-Jensen medium only 54.1%. Combination of the Bactec and MB-Check systems allowed recovery of 100% of isolates. The Bactec system showed a faster detection time than the other two methods.


Application of the polymerase chain reaction in the diagnosis of pulmonary toxoplasmosis in immunocompromised patients. Bronchoalveolar lavage (BAL) fluid from 47 immunocompromised patients (26 with AIDS and 21 patients on immunosuppressive therapy) was analysed for the presence of Toxoplasma gondii DNA by means of the polymerase chain reaction (PCR). Specific target DNA derived from the B1 and P30 gene of Toxoplasma gondii was detected in BAL fluids from three patients with AIDS (6.4%). Pneumonia as the presenting feature of disseminated toxoplasmosis was confirmed by both clinical findings and by detection of Toxoplasma gondii DNA in blood obtained from two patients. The findings indicate that PCR has potential value in the detection of Toxoplasma gondii as an etiologic agent of atypical pneumonia in immunocompromised patients.


Influence on survival of p24 antigen levels in patients with AIDS or advanced AIDS related complex treated with zidovudine. In a prospective study sixty-eight patients consecutively diagnosed as having AIDS or advanced ARC who were started on zidovudine therapy were followed up for a median period of 725 days. In the 20 patients who had a baseline p24 antigen level above 20 pg/ml, there was a statistically significant trend towards reduction of the p24 antigen levels after the first month of treatment. The median time of survival of the 68 patients was 702 days and the median symptom-free period was 510 days. Treatment with zidovudine significantly reduced the p24 antigen levels. However, the life expectancy and the symptom-free period were not statistically different in the patients with p24 antigen levels always below or with levels always above two arbitrarily chosen cut-off points of 20 pg/ml and 50 pg/ml, respectively.


Activity of meropenem against imipenem-resistant bacteria and selection in vitro of carbapenem-resistant Enterobacteriaceae. The activity of meropenem against 106 imipenem-resistant (MIC > or = 8 mg/l) clinical isolates, and the frequency of resistance to meropenem and imipenem among 24 Enterobacteriaceae was determined. Both agents selected colonies on agar but 20-80% were susceptible after one subculture and 72% of the mutants reverted to susceptibility 1 to 6 months after selection. All isolates and stable mutants were inhibited by > 1 mg/l meropenem, although the MIC of imipenem was 4-16 mg/l. Three of six Xanthomonas maltophilia isolates were susceptible to meropenem (MICs 2-4 mg/l). Pseudomonas aeruginosa lacking outer membrane protein D2 were resistant to meropenem, although isolates with substantially reduced expression of this protein were susceptible. None of the imipenem-resistant gram-positive bacteria were susceptible to meropenem. There was no clear correlation between altered outer membrane protein expression and decreased susceptibility to carbapenems, and there was no apparent involvement of plasmid or chromosomal beta-lactamase.


[Incidence of tongue diseases based on epidemiologic studies (review of the literature)]. According to the literary data the prevalence of fissured tongue varies between 0.8-60.0%, that of geographic tongue between 0.1-14.3%, that of atrophy tongue between 1.3-9.0% and that of the central papillary atrophy of the tongue between 0.0-3.35%. The wide-ranging diversity concerning the epidemiological data of tongue diseases can be explained by the multiple character of sampling, diagnosis and other methods used in different types of examinations. Disregarding the extremities and considering the average prevalence data, these agree in general with the epidemiological data found in Hungary in 1990: fissured tongue 8.8% geographic tongue 3.0%, atrophic tongue 6.37% and central atrophy of the tongue 0.35% prevalence.


[Laser in contemporary dentistry].

[Laser in contemporary dentistry]. In the 30 years of laser history the oral cavity application has always played an important role. In the laboratory diagnostics the analysis of the saliva, tissues and hard dental tissues is performed by laser. In the clinical diagnostics the laser is used for examining the caries, dental matter, in orthodontics, in the surgical analysis of splanchnocranium and the teeth. The photodynamic treatment involves the diagnostic and therapeutic use of the lasers in the management of oral cavity cancers. The soft laser therapy is widely applied in diseases of the oral mucosa, parodontal and pain syndromes, temporomandibular articular diseases, dental inflammations, salivary gland diseases and in osseal healing processes. The surgical lasers are applied in the treatment of teeth, in preprosthetic surgery, salivary gland diseases, precancerous conditions, tumour surgery and in the surgery of hemophilic patients, respectively. In the 90s one cannot speak about modern oral surgery or dentistry without the application of lasers. Though in various fields the research is merely in initial phase (holography, caries-treatment, photodynamic therapy, etc.), the lasers are becoming an indispensable (treatment of precancerous conditions, hemophilic patients, diseases of the oral mucosa, etc.). The oral surgical use of lasers might bring about fundamental changes in diagnosis and treatment, becoming a new professional branch, opening up new vistas, representing "future" today. The invention of lasers in 1960 and their broad dissemination in oral surgery and dentistry since 1980 have resulted in basic changes in numerous diagnostic and therapeutic approaches. The medical use of lasers is of such an extent that it can well justifiably regarded as a new branch of science namely the laser medicine. This considerably relates to stomatology, too.


[Conditions of successful endosseous dental implantations]. The conditions of success of endosteal dental implants have been summarized on the base of the literature and own experiences. Three corresponding factors may determine the success: biocompatibility, biological seal, and the optimal force transfer. On the base of the data, the implantology is a biological way in the rehabilitation of edentulousness, if the conditions are kept in mind and are applied to the clinical practice.


[Stomatologic implications of diseases of the locomotor apparatus]. The authors describe rheumatic diseases with stomatological manifestations. There are some rheumatic diseases very frequently accompanied by oral symptoms. The author emphasize the importance of the cooperation between the rheumatologist and dentist in cases when the etiology of the stomatological changes is uncertain.


[Free-end reconstruction by dento-osseous autotransplantation]. The authors describe an endosseal autotransplantation A tooth is extracted together with its parodontium and the surrounding bone. It is implanted into a different place where the bone had been prepared. Upper left unilateral free-end saddle cases were solved by removing the tooth No 24 into the place of No 27. A bridge was constructed after 6 weeks using the 23 as abutment. The metal-ceramic bridges have been used by the patients for 3 years without complaint.


[Clinical analysis of the sodium-fluoride and sodium-monofluorophosphate content of Colgate toothpaste]. After six weeks use of Colgate toothpaste (1000 ppm MFP and 450 ppm NaF) in case of 50 individuals (25 test and 25 control persons) both the Plaque Index of Silness and Löe and the modified Sulcus Bleeding Index--"bleeding on probing" (Mühlemann and Son) mean values showed a significant decrease. According to the results of cytological testing the effect of toothpaste containing MFP and NaF proved favourable. The investigation of the ionisable plaque fluoride content produced statistically significant rise in plaque fluoride content.


[Inclusion cysts. Case report].

[Inclusion cysts. Case report]. Inclusion cysts which are developmental anomalies can be seen either along the midpalatine raphe or on the dental ridges as well as on other areas of the palate in newborns. Based on their localisation and histology these are classified into three types (Epstein's pearls, Bohn's nodules, Dental lamina cysts). These are often taken as natal or neonatal teeth. No treatment is indicated since the lesions will spontaneously disappear few weeks after birth.


[Linear model of the pathogenesis of the temporomandibular pain-dysfunction syndrome]. In the research of temporomandibular pain-dysfunction syndrome the etiological model of disease was created by a statistical system not applied until now. Of this it can be concluded that for the formation of the disease psychotic factors and oral parafunctions are responsible. Of the examination it became apparent that the cross sectional examination of the casual factors of the disease should be advisably carried out together with their correlations.


[Experience with the use of mini-plates in the surgical management of orbital frame fractures]. The authors have reported about their experiences in the surgical treatment of orbital-frame. Champy plate osteosynthesis was performed in 11 cases for the surgical treatment of orbital frame fractures, which had considerably dislocation. The method is advised in the surgical treatment of middle-face fractures.


[Mechanism of renin release and cellular action of angiotensin II]. Renin-angiotensin (RA) system plays an important role in cardiovascular homeostasis. Here, we have described the recent progress in our study of renin release as well as the cellular action of angiotensin II. (1) Microdissection of an isolated afferent artery with or without macula densa (MD) has revealed that renin release is regulated by NaCl exposure to MD. Furosemide, prostaglandins (PGE2 and PGI2) and adenosine modulate its function. (2) Angiotensin (ang) II increases cytosolic free calcium and induces the formation of inositolphosphates in vascular smooth muscle cells. Deduced protein structure of ang II receptor (AT1-R) cDNA has indicated the presumed link of AT1-R with phospholipase C. Through the cellular action, ang II has been reported to regulate gene expression.


[A case of Cushing's disease associated with a non-functioning adrenal tumor]. A 52-year-old woman was admitted to our hospital for further examination of central obesity, hypertension and hirsutism suggesting Cushing's syndrome. Hirsutism had been remarkable for two years, and muscle weakness of the lower extremities gradually developed during the past year. CT scan revealed a tumor in the left adrenal gland which was 1 cm in diameter, round, well-circumscribed, homogeneous and not enhanced. Endocrine data disclosed increased urinary 17-OHCS (11.5-16.4 mg/day) and elevated plasma ACTH (125 pg/ml) and cortisol (19 micrograms/dl) with a lack of diurnal rhythm. Administration of the single-dose dexamethasone (1mg) did not suppress plasma cortisol. However, consecutive administration of either 2mg or 8mg of dexamethasone for 2 days suppressed both plasma cortisol and urinary 17-OHCS. Administration of metyrapone raised both urinary 17-OHCS and plasma ACTH levels. Rapid ACTH test resulted in a hyperresponse of plasma cortisol. CRF injection raised plasma ACTH and cortisol. Bilateral adrenal glands were well demonstrated by 19-iodocholesterol (I-131) scintigraphy during the administration of dexamethasone. MRI with Gd-contrast revealed a microadenoma in the sella turcica. With the diagnosis of Cushing's disease, the microadenoma was removed by the transsphenoidal approach and adrenal function was normalized. However, the left adrenal tumor remained on CT scan but was not demonstrated by scintigraphy. These findings indicate that this is a very rare case of Cushing's disease which was associated with an unilateral non-functioning adrenal tumor.


[The mechanism of glucose intolerance in patients with Graves' disease]. To investigate the mechanism of glucose intolerance in patients with Graves' disease, a 2-hour oral glucose tolerance test and euglycemic glucose clamp study using Biostator were performed in patients with Graves' disease and control subjects. 80 per cent of the patients showed impaired glucose tolerance. Insulinogenic index in the patients with borderline or diabetic glucose response was lower than that in subjects with normal glucose response. Insulinogenic index was inversely correlated with sigma PG during the test. Despite normal basal plasma glucose concentrations, basal plasma insulin levels in the patients with Graves' disease were higher than in the controls. Using the euglycemic glucose clamp technique, the glucose utilization rate (M value), the metabolic clearance rate of glucose (MCRG) and the insulin sensitivity index (M/I x 100) in the patients with Graves' disease were lower than in the controls. After treatment with antithyroid drug in 3 patients, glucose tolerance completely normalized, and there was a significant increase in the M value and the MCRG and a significant decrease in the metabolic clearance rate of insulin (MCRI) compared to the values before treatment. In the patients with Graves' disease, basal serum glucagon levels were higher than in the controls, and glucagon suppression during insulin infusion was found to be decreased. From these data, it is concluded that the decrease in glucose tolerance in patients with Graves' disease can be explained by 1) the impairment of early insulin release response to rapid intestinal glucose absorption, 2) increased insulin metabolic clearance and 3) hyperglucagonemia.


[A case of insulinoma with frequent hypoglycemic attacks not showing evident hyperinsulinemia]. Confirmation of inappropriate hyperinsulinemia is an indispensable requisite for the diagnosis of insulinoma. We report here a case of insulinoma without evident hyperinsulinemia at an early stage. The patient, a 49-year-old woman, had been admitted to our hospital for the evaluation of frequent hypoglycemic attacks. At that time, plasma immunoreactive insulin (IRI) after an overnight fast ranged from 7 to 16 microU/ml. The ratio of IRI/fasting blood sugar (FBS) (Fajans index; normal range, below 0.3) was always between 0.13 and 0.28 even at hypoglycemic states. In addition, because computed tomography and arteriography of the abdomen failed to settle the diagnosis of insulinoma, the patient was discharged and followed up at our outpatient clinic for 2 years. She was admitted to our hospital at 51 years of age for the re-evaluation of hypoglycemic attacks. Laboratory examinations revealed high fasting plasma levels of IRI ranging from 20 to 29 microU/ml. Fajans index also increased to 0.47-0.89. Celiac arteriography was able to confirm the existence of insulinoma. We suggest that insulinoma should be considered in the presence of unexplained hypoglycemic attacks even when there is no evident hyperinsulinemia.


[Studies on the production rate of estradiol in the testis in male infertility--studies of the predictive values on therapeutic efficacy in patients with oligozoospermia]. It is surmised that studies on the relationship between the endocrinological milieu and therapeutic efficacy in male infertile patients are essential in elucidating the etiology of this disease and devising effective therapeutic methods. The relation between serum gonadotropin level and therapeutic efficacy has already been reported. In the present study, we investigated the basal levels of two sex steroids, i.e., testosterone and estradiol, and the estradiol:testosterone (E2/T) ratio, and also the increases in these parameters after the administration of hCG to human subjects presenting various degrees of testicular dysfunction, e.g., male infertile patients, aged males, Klinefelter's syndrome and hypogonadotropic hypogonadism. Special attention was given to the characteristics of the reserve capacity for secretion of estradiol in male infertile patients. The hCG test was performed on a total 527 subjects, including 65 normal adult males. The reserve capacity for the secretion of estradiol was investigated on the basis of the increasing rate in the serum E2/T ratio. The increasing rate in the serum E2/T ratio was statistically larger in subfertile males, oligozoospermia and azoospermia in comparison with the normal adult males. On the other hand, the aged males did not show any difference from the normal adult males, whereas the results were significantly lower in the male subjects with Klinefelter's syndrome and hypogonadotropic hypogonadism. It was considered that the increase in the serum E2/T ratio is one characteristic of the gonads of male infertile patients. The results of multiple regression analysis showed that the LH level, the pretreatment sperm concentration and the increasing rate in the serum E2/T ratio were important factors determining the increase in the sperm concentration after treatment. Accordingly, for cases of oligozoospermia characterized by an LH level of 13.7mIU/ml or less and a sperm concentration of 5 x 10(6)/ml or more, the relationship between the increasing rate in the serum E2/T ratio and therapeutic efficacy was investigated. It was found that the increasing rate in the serum E2/T ratio was significantly greater in the therapeutically ineffective cases compared with the therapeutically effective cases. On the basis of this finding, it was surmised that the percentage increase in the serum E2/T ratio is one index reflecting testicular function. In addition, for cases of oligozoospermia characterized by an LH level of 13.7mIU/ml or less, a sperm concentration of 5 x 10(6)/ml or more and the increasing rate in the serum E2/T ratio of 4.01 or less, the relationship between the degree of spermatogenesis and therapeutic efficacy was investigated.(ABSTRACT TRUNCATED AT 400 WORDS)


[A case of esophageal carcinoma with hypercalcemia caused by PTH-rP--the effect of therapy on the bone and calcium metabolism]. The changes in the bone and in calcium metabolism during cisplatin or bisphosphonate administration is reported in a 50-year-old patient with esophageal carcinoma who had humoral hypercalcemia of malignancy (HHM). Laboratory findings on admission showed that ionized calcium was 1.65mmol/L, phosphorus was 2.4mg/dl, and PTH-rP was 151pmol/L, without any evidence of bone metastasis. After admission, cisplatin and/or bisphosphonate were administrated for hypercalcemia. These administrations ameliorated serum ionized calcium, urinary pyridinoline and hydroxyproline level within a few days. Although cisplatin administration decreased the serum osteocalcin level, bisphosphonate administration kept up the level, suggesting that bisphosphonate maintained bone formation and cisplatin decreased its formation. The discrepancy may be due to the coupling with the reduction of bone resorption and/or direct toxic effect on osteoblasts during cisplatin administration, and preservation of osteoblastic activity during bisphosphonate administration. Cisplatin and bisphosphonate may have different effects on bone formation. Serum 1,25(OH)2D level was slightly decreased or unchangeable after cisplatin administration, although the level was increased after bisphosphonate administration. Direct toxic effect on 1 alpha-hydroxylase of the kidney or increase in phosphrous level may explain the change of 1,25(OH)2D after cisplatin administration. These results suggested that cisplatin and bisphosphonate have the same effect of preventing bone resorption but different effects on bone formation and/or serum 1,25(OH)2D level.


Esbiothrin-impregnated ropes as mosquito repellent. Esbiothrin [(+/-)-3-allyl-2-methyl-4-oxocylopent-2-enyl-(+)-trans- chrysanthemate] is an improved isomeric composition of allethrin series and consists essentially of esters of chrysanthemic acid and allethrolone. Jute rope was impregnated with esbiothrin and the smoke from smouldering ropes was evaluated as mosquito repellent in human dwellings and cattlesheds with open doors and windows at different dosages. Esbiothrin-impregranted (500 ppm) ropes prevented the entry of more than 95% An. culicifacles and other anophelines, 90.9-88.8% Culex quinquefasciatus and 96-95.1% total mosquitoes in open rooms of houses and cattlesheds respectively. The impact of ropes was more pronounced on the biting rate of mosquitoes. Indoors and outdoors human baits seated at a distance of about 3 m from smouldering esbiothrin ropes experienced no bite at all from An. culicifacies. An iron mesh around the rope prevents fire hazards.


Sensitivity status of Plasmodium falciparum to chloroquine, amodiaquine, quinine, mefloquine and sulfadoxine/pyrimethamine in a tribal population of District Sundargarh, Orissa. In a malaria-endemic area of Orissa, wherein chloroquine has been in use for over thirty years, 58.3% (14/24) P. falciparum cases did not respond to single dose chloroquine (10 mg base/kg) in in-vivo test. With standard dose (25 mg base/kg) 31.2% cases (10/32) showed resistance, i.e. at RI (15.6%), RII (9.4%) and RIII (6.2%) levels. Standard dose was superior in response to the single dose therapy [p < 0.05; chi 2 (df 1) = 4.11]. Out of eight isolates tested in vitro, two showed resistance to chloroquine, five to sulfadoxine/pyrimethamine (SP) but all were sensitive to amodiaquine, quinine and mefloquine. Whereas the standard dose of chloroquine would be a better option in general, in resistant cases, SP, quinine and mefloquine offer an alternative drug choice. The implications of drug resistance in a malaria-control programme and the need to revise drug policy in India are discussed.


Malaria epidemic in Baniyani village, District Farrukhabad (U.P.). Many deaths were recorded in village Baniyani of Talgram PHC of District Farrukhabad, U.P. during August to November 1991, which is the malaria transmission season in this area. Integrated measures, like one-round spraying of DDT and HCH, six-round fogging of malathion and six-time application of Baytex in mosquito breeding sites, were adopted by the Health Department of the U.P. government to avert an epidemic. Investigations carried out by the Malaria Research Centre during November and December 1991 showed low mosquito densities and larval positivity but very high incidence of malaria in the village. No malaria case was recorded by the surveillance worker of the Health Department of the state government before the outbreak of the disease. However, high slide falciparum rate (51.57), child parasite rate (40.0), infant parasite rate (66.66) and spleen rate (82.90) in the village clearly indicated hyperendemic conditions in the area and hence deaths recorded in the village during the malaria transmission period could be due to malaria only. Major factors responsible for the deaths due to malaria in the village were poor surveillance, faulty diagnosis, and low literacy and socio-economic status of the villagers.


Frequency of ABO blood groups, sickle-cell haemoglobin, G-6-PD deficiency and their relation with malaria in scheduled castes and scheduled tribes of Kheda District, Gujarat. Frequency of sickle cell in Scheduled Caste and Scheduled Tribe populations was found to be 1.5 and 14.9% respectively, whereas G-6-PD deficiency was 5.9 and 4.2% respectively. Blood group B was dominant in both the communities. A significantly lower frequency of P. falciparum malaria was observed among sicklers.


Malaria and ABO blood groups.

Malaria and ABO blood groups. Subjects from Muria gond tribal community (n = 258) as well as from Delhi (n = 100) were classified according to ABO blood groups, and were also assayed for malarial antibodies by ELISA technique. The distribution of ABO blood groups did not differ significantly in Muria gonds and Delhi subjects. Within Muria gonds the observed frequency of ABO blood groups did not differ significantly from the expected values. No significant difference was observed in the rate of seropositivity for malarial antibodies among subjects with different blood groups. Malarial parasitaemia, although observed more in individuals with blood group A, did not differ significantly as compared with other blood groups. We conclude that ABO blood groups do not show differential susceptibility to malaria.


Carpal tunnel syndrome. Risk factors and preventive strategies for the dental hygienist. Carpal tunnel syndrome (CTS) is well recognised as an occupational risk for dental hygienists. The contributing risk factors fall primarily into two categories: medical and occupational. The purposes of this paper are to examine the factors that predispose one to CTS in order to increase awareness among dental hygienists, and to offer preventive strategies that can be incorporated into daily practice.


The immune response to oral infections.

The immune response to oral infections. This article summarizes some of the important interactions between the immune system and inflammatory process, with the primary focus on the host response to infection. A subsequent brief review of the pathogenesis of periodontal disease serves to illustrate the relevance of these interactions to our understanding of disease.


Resin-Bonded bridges: 1. Development and casting design. This series of two articles will consider the developments and clinical techniques of resin-bonded bridges with the emphasis on methods for increasing success from a functional and aesthetic view point.


Update on periodontology: 2. Diagnosis in periodontology. The second in this series of articles looks at the problems of diagnosis in periodontology. This is an area that is often neglected in the routine examination of patients, but with the introduction of systems like CPITN the examination of patients with periodontal disease is becoming easier.


The diagnosis of dental caries: 3. Rationale and overview of present and possible future techniques. A number of changes have taken place recently which may influence a practitioners choice of diagnostic methods for detecting and monitoring dental caries. The first two articles described the use of current diagnostic methods at various specific sites. This third paper discusses the rationale behind the use of these techniques and provides an overview of present techniques and those which may be useful in the future.


Oral care of the HIV-infected patient.

Oral care of the HIV-infected patient. There are only a small number of specialized centres that cater for the dental care of the steadily increasing number of HIV-infected individuals. The responsibility will, therefore, be increasingly shared with the dental practitioner who should be knowledgeable on the basic oral management protocols involved in treating these individuals. This article summarizes some essentials of oral health care in HIV-infected individuals.


Hemisection: a treatment option for the vertically split tooth. As the population keeps their teeth longer the problem of tooth fracture and severe fracture of the root is becoming increasingly significant for the restorative dentist. This paper discusses hemisection, an alternative to extraction in cases of vertical root fracture in patients capable and willing to carry out proper oral hygiene measures.


Sedation in dental practice.

Sedation in dental practice. The recent publication of the Department of Health's report from the Expert Working Party on General Anaesthesia, has made recommendations on sedation in the dental practice. This article discusses the use of benzodiazepines by the general dental practitioner.


The specific plaque hypothesis and the antimicrobial treatment of periodontal disease. According to the specific plaque hypothesis a measurable amount of periodontal disease is due to the overgrowth of specific bacterial types. The author advocates the theory and discusses treatment. This includes techniques for diagnosing the predominant bacterial types, antibiotic therapy and the relevance of regular debridement.


Quality assurance: 1. Reject analysis, operator technique and the X-ray set. Number 1 of the series, which will present the 'core knowledge' on radiography, is designed to help the dentist produce the highest quality radiographs and appears in two parts. Part 1 discusses the identification of problems and how to solve those related to operator technique and the X-ray set, while part 2 will comment on problems with the image receptor, the darkroom and processing.


Resin-bonded bridges: 2. Treatment planning, clinical gases and failures. This is the second paper in the two-part series which considers the developments and clinical techniques of resin-bonded bridges with the emphasis on methods for increasing success from a functional and aesthetic view point. Part 1 focused on the development and types of resin-bonded bridge and tooth preparation. This article describes the clinical application of this type of bridge and discusses failures.


Post-endodontic pericoronitis.

Post-endodontic pericoronitis. Pericoronitis is defined as inflammation of the soft tissue around the crown of any partially erupted tooth. A case of pericoronitis with an unusual aetiology is described.


Food and oral health: 1. Dental caries.

Food and oral health: 1. Dental caries. Dental schools tend to teach only the rudiments of this subject and this does not provide a good basis for dentists to advise patients and combat the misinformation surrounding the topic. The first article in the two-part series examines nutrition as it applies to dental caries, while part two will discuss some of the general principles of nutrition in relation to oral health, periodontal disease and the oral mucosa.


Aesthetic brackets: to perfect or to reject? Orthodontists are now treating patients who are demanding high quality orthodontics which is also aesthetically pleasing. The quest for an aesthetic yet strong appliance has led to many innovative designs. This article summarizes the main advances.


Lasers in dentistry.

Lasers in dentistry. Lasers, which are constantly evolving, can be customized to meet dental requirements and could become a very useful tool for dental practitioners. The article provides an introduction to the instruments, which includes a description of how they work and discusses their applications in dentistry.


Quality assurance: 2. The image receptor, the darkroom and processing. Number 1 of the series, which presents the 'core knowledge' on radiography, is designed to help the dentist produce the highest quality radiographs and appears in two parts. Part 1 discussed the identification of problems and how to solve those related to operator technique and the X-ray set, whilst this article will comment on difficulties with the image receptor, the darkroom and processing.


Dental practitioner attendances at postgraduate courses in a dental school 1988-90. The attendance pattern of dental practitioners who resided in the West Midlands on postgraduate courses at Birmingham University Dental School was studied over a two-year period. This paper provides an insight into the trends occurring in postgraduate training in this area.


Tongue in cheek.

Tongue in cheek. Apyogenic granuloma is an innocent lesion commonly found on the gingiva, but can occur at other oral sites. A case is reported of a tongue lesion which had been present for 20 years and is unusually large.


Management of oral complications following radiotherapy. Radiotherapy for the treatment of neoplastic disease in the head and neck region results in a number of oral changes liable to cause pain and discomfort during therapy. In the longer term, it increases the patient's susceptibility to caries and periodontal disease. The aim of this paper is to outline these changes and to suggest a regime for the dental management of these patients before, during and after radiotherapy. The role of the dentist in support, advice and treatment is vital.


The use of dental amalgam--an art or a science? Dental amalgam remains the best material for filling teeth when aesthetics are of secondary importance. Over the last 20 years improvements in the composition have reduced marginal failure due to creep and corrosion, and the use of modern adhesives has lead to an early seal between the tooth and the filling. However, the proper handling by the dentists remains as the cornerstone for fillings that are going to last. This article describes the history, classification, structure and handling variables of dental amalgams. It also discusses the effects of extra elements, bonding agents and the possible hazard of mercury.


Selected issues on care and management of the ageing patient: 2. Prevention and treatment. The elderly are a vulnerable group of patients in whom even simple dental care can become invasive and require the use of a local anaesthetic. Part 1 assessed the factors which may influence the ability of the patient to receive treatment and established treatment priorities. It also described the particular problems that may arise when dealing with the elderly and indicated the adjustments of a practice which would help in the care of these patients. Part 2 will now discuss prevention and treatment.


Dental demolition.

Dental demolition. A proportion of our chairside time is spent in replacing defective restorations. However, many of the well known textbooks on restorative dentistry describe how high quality restorations should be produced, but not the techniques for removing faulty ones. This article discusses some of these techniques. It examines the removal of nonadhesive and adhesive plastic restorations, veneers, inlays, root fillings, crowns and bridges. The removal of foreign objects and posts from root canals has been described elsewhere and so will not be discussed here.


Electrosurgery in restorative dentistry: 1. Theory. Electrosurgery techniques have been used in dentistry as an aid to soft tissue management for nearly 60 years. However, it was not until the late 1960s that the principles of electrosurgery were understood and improved equipment became available. Part 1 of this two-part series covers the theory behind using this technique. Part 2 will discuss the clinical applications.


Alternatives to gold.

Alternatives to gold. Despite, or perhaps because of, its antiquity the lost wax casting process which we use in dentistry still produces the most accurate and durable restorations in our armamentarium. Although high-gold content alloys still act as the benchmark of quality, fit, and durability in the aggressive conditions of the mouth, their inherent cost, high density and low modulus have stimulated a search for alternatives. This has ranged widely through the metallurgical world and across the periodic table of the elements. As a result dental alloys for casting into inlays, crowns and bridges (with or without facings of dental porcelain) have become incredibly complex. This article will explain some of the reasons behind the developments.


Advances in fixed appliance design and use: 2. Auxiliaries, adhesives, appliance care and debonding. Many new developments in design and materials have made it easier for orthodontists to produce good results with fixed appliances in a shorter time. Orthodontic treatment has also become more comfortable and aesthetically pleasing for patients. This is the second of two papers which are intended to provide an update on fixed appliance design and use, so patients can be informed of relevant advances before they are referred to a specialist for orthodontic advice. Part 1 discussed the development in brackets and archwires. Part 2 will now cover recent advances in ligatures and elastomeric ties, intraoral auxiliaries, adhesives, products to assist oral hygiene and prevention during fixed appliance treatment, and new methods of debonding.


Glove wearing by dental surgery assistants in general practice: results of a survey. Cross-infection routines should be used by both the dentist and the dental surgery assistant (DSA), and the wearing of gloves during patient treatment is considered an integral part of such routines. Results are presented which indicate the extent to which DSAs wear gloves while assisting in patient care, and the factors influencing glove wearing are discussed.


Effective periodontal control.

Effective periodontal control. One of the major difficulties in periodontal care is that knowing the principles is of very little practical help when it comes to treating individual patients. This article discusses the identification of susceptible patients, the measurements of sites of disease and identification of active bursts of disease when the patient is on a maintenance programme that can be easily performed by the dental practitioner.


Clinical aspects of occlusion: 1. Occlusal terminology and the conformative approach. This two-part series aims to familiarize the reader with essential occlusal principles and terminology and to give some guidelines as to which cases are suitable for crown and bridgework. The first article covers occlusal terminology and the conformative approach, whilst the second will describe the reorganized approach. Both papers contain clinical cases which demonstrate how to overcome some of the occlusal problems encountered in this area.