Adsorption of aqueous metal ions on oxygen and nitrogen functionalized nanoporous activated carbons

In this study, the adsorption characteristics of two series of oxygen and nitrogen functionalized activated carbons were investigated. These series were a low nitrogen content (approximately 1 wt % daf) carbon series derived from coconut shell and a high nitrogen content (approximately 8 wt % daf) carbon series derived from polyacrylonitrile. In both series, the oxygen contents were varied over the range approximately 2-22 wt % daf. The porous structures of the functionalized activated carbons were characterized using N(2) (77 K) and CO(2) (273 K) adsorption. Only minor changes in the porous structure were observed in both series. This allowed the effect of changes in functional group concentrations on metal ion adsorption to be studied without major influences due to differences in porous structure characteristics. The surface group characteristics were examined by Fourier transform infrared (FTIR) spectroscopy, acid/base titrations, and measurement of the point of zero charge (pH(PZC)). The adsorption of aqueous metal ion species, M(2+)(aq), on acidic oxygen functional group sites mainly involves an ion exchange mechanism. The ratios of protons displaced to the amount of M(2+)(aq) metal species adsorbed have a linear relationship for the carbons with pH(PZC) < or = 4.15. Hydrolysis of metal species in solution may affect the adsorption of metal ion species and displacement of protons. In the case of basic carbons, both protons and metal ions are adsorbed on the carbons. The complex nature of competitive adsorption between the proton and metal ion species and the amphoteric character of carbon surfaces are discussed in relation to the mechanism of adsorption.

Hydrogen Adsorption on Functionalized Nanoporous Activated Carbons

There is considerable interest in hydrogen adsorption on carbon nanotubes and porous carbons as a method of storage for transport and related energy applications. This investigation has involved a systematic investigation of the role of functional groups and porous structure characteristics in determining the hydrogen adsorption characteristics of porous carbons. Suites of carbons were prepared with a wide range of nitrogen and oxygen contents and types of functional groups to investigate their effect on hydrogen adsorption. The porous structures of the carbons were characterized by nitrogen (77 K) and carbon dioxide (273 K) adsorption methods. Hydrogen adsorption isotherms were studied at 77 K and pressure up to 100 kPa. All the isotherms were Type I in the IUPAC classification scheme. Hydrogen isobars indicated that the adsorption of hydrogen is very temperature dependent with little or no hydrogen adsorption above 195 K. The isosteric enthalpies of adsorption at zero surface coverage were obtained using a virial equation, while the values at various surface coverages were obtained from the van't Hoff isochore. The values were in the range 3.9-5.2 kJ mol(-1) for the carbons studied. The thermodynamics of the adsorption process are discussed in relation to temperature limitations for hydrogen storage applications. The maximum amounts of hydrogen adsorbed correlated with the micropore volume obtained from extrapolation of the Dubinin-Radushkevich equation for carbon dioxide adsorption. Functional groups have a small detrimental effect on hydrogen adsorption, and this is related to decreased adsorbate-adsorbent and increased adsorbate-adsorbate interactions.

Reactions of nitrogen and oxygen surface groups in nanoporous carbons under inert and reducing atmospheres

The reactions of surface functional groups have an important role in controlling conversion of char nitrogen to NOx during coal combustion. This study involved an investigation of the thermal stability and reactions of nitrogen surface functional groups in nanoporous carbons. Four suites of carbons, which were used as models for coal chars, were prepared with a wide range of nitrogen and oxygen contents and types of functional groups. The porous structures of the carbons were characterized by gas adsorption methods while chemical analysis, X-ray photoelectron spectroscopy, and X-ray near edge structure spectroscopy were used to characterize the surface functional groups. Temperature programmed desorption and temperature programmed reduction methods were used to study the reactivity of the surface functional groups during heat treatment under inert and reducing conditions. Heat treatment studies show that the order of stability of the functional groups is quaternary nitrogen > pyridinic > pyrrolic > pyridine N-oxide. Pyridine N-oxide surface groups desorb NO and form N2 via surface reactions at low temperature. Pyrrolic and pyridinic functional groups decompose and react with surface species to give NH3, HCN, and N2 as desorption products, but most pyrrolic groups are preferentially converted to pyridinic and quaternary nitrogen. The main desorption product is N2. Approximately 15-40 wt % of the original nitrogen was retained in the carbons mainly as quaternary nitrogen after heat treatment to 1673 K. The results are discussed in terms of decomposition ranges for surface functional groups and reaction mechanisms of surface species.

Crystallization of a 14-3-3 protein

Crystals of the tau (tau) isoform of the 14-3-3 family of proteins were grown and shown to belong to the orthorhombic space group P2(1)2(1)2(1) with cell dimensions a = 70.29, b = 79.3, c = 101.00 A. The crystals were needle-like in morphology and less than 10 micro m in two dimensions. Diffraction data were collected using synchrotron radiation sources from flash-cooled crystals. Native data extended to a resolution of 2.6 A and mercury and platinum derivatives diffracted to 3.4 and 3.9 A, respectively. The structure has been solved recently. Here the protein crystallization procedures, the characterization of the crystals and the correlation between crystal habit and diffraction quality are reported.

H1 and H7 influenza haemagglutinin structures extend a structural classification of haemagglutinin subtypes

Comparing the structures of H3, H5 and H9 subtype haemagglutinins, we deduced a structural basis for including all 15 influenza subtypes in four clades. H3, H5 and H9 represent three of these clades; we now report the structure of an H7 HA as a representative of the fourth clade. We confirm the structure of the turn at the N-terminus of the conserved central alpha-helix of HA2, and the combination of ionisable residues near the "fusion peptide" as clade-specific features. We compare the structures of three H1 HAs with H5 HA in the same clade, to refine our previous classification and we confirm the division of the clades into two groups of two. We also show the roles of carbohydrate side chains in the esterase-fusion domain boundaries in the formation of clade-specific structural markers.

Competitive adsorption of aqueous metal ions on an oxidized nanoporous activated carbon

Competitive adsorption is the usual situation in real applications, and it is of critical importance in determining the overall performance of an adsorbent. In this study, the competitive adsorption characteristics of all the combinations of binary mixtures of aqueous metal ion species Ca2+(aq), Cd2+(aq), Pb2+(aq), and Hg2+(aq) on a functionalized activated carbon were investigated. The porous structure of the functionalized active carbon was characterized using N2 (77 K) and CO2 (273 K) adsorption. The surface group characteristics were examined by temperature-programmed desorption, Fourier transform infrared spectroscopy, Raman spectroscopy, acid/base titrations, and measurement of the point of zero charge (pHpzc). The adsorption of aqueous metal ion species, M2+(aq), on acidic oxygen functional group sites mainly involves an ion exchange mechanism. The ratios of protons displaced to the amount of M2+(aq) metal species adsorbed have a linear relationship for both single-ion and binary mixtures of these species. Hydrolysis of metal species in solution may affect the adsorption, and this is the case for adsorption of Hg2+(aq) and Pb2+(aq). Competitive adsorption decreases the amounts of individual metal ions adsorbed, but the maximum amounts adsorbed still follow the order Hg2+(aq) > Pb2+(aq) > Cd2+(aq) > Ca2+(aq) obtained for single metal ion adsorption. The adsorption isotherms for single metal ion species were used to develop a model for competitive adsorption in binary mixtures, involving exchange of ions in solution with surface proton sites and adsorbed metal ions, with the species having different accessibilities to the porous structure. The model was validated against the experimental data.

The Structure and Receptor Binding Properties of the 1918 Influenza Hemagglutinin

The 1918 influenza pandemic resulted in about 20 million deaths. This enormous impact, coupled with renewed interest in emerging infections, makes characterization of the virus involved a priority. Receptor binding, the initial event in virus infection, is a major determinant of virus transmissibility that, for influenza viruses, is mediated by the hemagglutinin (HA) membrane glycoprotein. We have determined the crystal structures of the HA from the 1918 virus and two closely related HAs in complex with receptor analogs. They explain how the 1918 HA, while retaining receptor binding site amino acids characteristic of an avian precursor HA, is able to bind human receptors and how, as a consequence, the virus was able to spread in the human population.

Kindling-induced overexpression of Homer 1A and its functional implications for epileptogenesis

Despite an extensive research on the molecular basis of epilepsy, the essential players in the epileptogenic process leading to epilepsy are not known. Gene expression analysis is one strategy to enhance our understanding of the genes contributing to the functional neuronal changes underlying epileptogenesis. In the present study, we used the novel MPSS (massively parallel signature sequencing) method for analysis of gene expression in the rat kindling model of temporal lobe epilepsy. Kindling by repeated electrical stimulation of the amygdala resulted in the differential expression of 264 genes in the hippocampus compared to sham controls. The most strongly induced gene was Homer 1A, an immediate early gene involved in the modulation of glutamate receptor function. The overexpression of Homer 1A in the hippocampus of kindled rats was confirmed by RT-PCR. In order to evaluate the functional implications of Homer 1A overexpression for kindling, we used transgenic mice that permanently overexpress Homer 1A. Immunohistochemical characterization of these mice showed a marked Homer 1A overexpression in glutamatergic neurons of the hippocampus. Kindling of Homer 1A overexpressing mice resulted in a retardation of seizure generalization compared to wild-type controls. The data demonstrate that kindling-induced epileptogenesis leads to a striking overexpression of Homer 1A in the hippocampus, which may represent an intrinsic antiepileptogenic and anticonvulsant mechanism in the course of epileptogenesis that counteracts progression of the disease.

[Apoptosis of CD4(+) T cells during experimental autoimmune neuritis in Wistar rats]

The present study describes apoptosis of T cells in the sciatic nerve in Wistar rats with experimental autoimmune neuritis(EAN). Morphological characterizations of apoptosis were found at the 18th day from onset, peaked at the 22nd day by immunocytochemical analysis. In situ end labeling(ISEL) techniques confirmed the presence of DNA fragmentation in CD4(+) T cells. It is suggested that apoptosis is an important clearance mechanism of infiltrated T cells in the peripheral nervous system(PNS) in EAN.

Multidrug-resistance-associated protein MGr1-Ag is identical to the human 37-kDa laminin receptor precursor

We report the isolation and functional characterization of the gene encoding MGr1-Ag, a multidrug-resistance-associated protein. A lambdagt11 cDNA library derived from colorectal carcinoma SW480 cells was screened with monoclonal antibody MGr1. DNA homology analysis of 22 positive clones (designated R1-R22) suggested human 37-kDa laminin receptor precursor (37LRP, R7/R9/R15/R16/R19/R20) and a novel gene (R22) as candidate genes encoding MGr1-Ag. Western blot analysis showed that anti-R20 serum reacted with a unique protein band that was consistent with MGr1-Ag, while anti-R22 serum could not react with MGr1-Ag. The coding gene for MGr1-Ag was amplified using reverse transcription-PCR. Sequence analysis revealed that the MGr1-Ag and 37LRP genes shared the same coding sequence. An in vitro drug sensitivity assay indicated that down-regulation of 37LRP by an antisense technique could significantly enhance the cytotoxicity of anticancer drugs to gastric cancer cells. Thus we draw the conclusion that MGr1-Ag is identical to 37LRP.

Structure and dynamics of 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase

Folates are essential for life. Unlike mammals, most microorganisms must synthesize folates de novo. 6-Hydroxymethyl-7,8-dihydropterin pyrophosphokinase (HPPK) catalyzes pyrophosphoryl transfer from ATP to 6-hydroxymethyl-7,8-dihydropterin (HP), the first reaction in folate pathway, and therefore, is an ideal target for developing novel antimicrobial agents. Because of its small size and high thermal stability, E. coli HPPK is also an excellent model enzyme for studying the mechanisms of enzymatic pyrophosphoryl transfer. We have determined the crystal structures of HPPK in the unligated form and in complex with HP, two Mg2+ ions, and AMPCPP (an ATP analog that inhibits the enzymatic reaction). Comparison of the two crystal structures reveals dramatic conformational changes of three flexible loops and many side chains and possible roles of the active site residues.

Adjuvant-induced arthritis: IL-1 beta, IL-6 and TNF-alpha are up-regulated in the spinal cord

Adjuvant-induced arthritis (AIA) is a widely used animal model of human rheumatoid arthritis (RA). We have previously shown that increased neuropeptide expression is observed in the spinal cord of AIA rats. To study the potential role of cytokines in the spinal cord of AIA, we wanted to determine whether there are changes of glial and cytokine expression (IL-1 beta, IL-6, TNF-alpha and IFN-gamma) in the spinal cord of AIA rats. Our data indicated that macroglia and MHC class II immunostaining were enhanced, astrocytes expressing GFAP were increased in number and immunostaining intensity. Using in situ hybridization and immunohistochemical methods, both mRNA and protein levels of IL-1 beta, IL-6 and TNF-alpha were significantly increased in the spinal cord of arthritic rats. Increased cytokine expression was presented in the reactive astrocytes and microglia.

Construction and selection of the natural immune Fab antibody phage display library from patients with colorectal cancer

AIM: To construct the natural immune Fab antibody phage display libraries of colorectal cancer and to select antibodies related with colorectal cancer.

METHODS: Extract total RNA from tissue of local cancer metastasis lymph nodes of patients with colorectal cancer. RT-PCR was used to amplify the heavy chain Fd and light chain κ and the amplification products were inserted successively into the vector pComb3 to construct the human libraries of Fab antibodies. They were then panned by phage display technology. By means of Dot immunoblotting and ELISA, the libraries were identified and the Fab phage antibodies binding with antigens of colorectal cancer were selected.

RESULTS: The amplified fragments of Fd and κ gained by RT-PCR were about 650 bp. Fd and κ PCR products were subsequently inserted into the vector pComb3, resulting in a recombination rate of 40% and the volume of Fab phage display library reached 1.48 × 10⁶. The libraries were enriched about 120-fold by 3 cycles of adsorption-elution-multiplication (panning). Dot immunoblotting showed Fab expressions on the phage libraries and ELISA showed 5 clones of Fab phage anti bodies which had binding activities with antigens of colorectal cancer.

CONCLUSION: The natural immune Fab antibody phage display libraries of colorectal cancer were constructed. They could be used to select the relative antibodies of colorectal cancer.

[Studies on liver cancer induced by non-necrotizing dose of diethylnitrosamine in rats]

OBJECTIVE

To provide an appropriate animal model of liver cancer and sensitive indicator for carcinogen risk assessment.

METHODS

The developmental processes of liver cancers in rats initiated by non-necrotizing dose of diethylnitrosamine and promoted by phenobarbital were studied.

RESULTS

Most of the preneoplastic lesions and liver cancers were made up of eosinophilic cells. The placental glutathione S-transferase (P-GST) staining could allow a lot of positive single cells, foci and nodules to be seen. But the lesions showed by HE staining expressed higher proliferating cell nuclear antigen (PCNA) than those showed by P-GST staining expressed, indicating a greater possibility for these lesions to persist and develop further. The cellular morphologic analysis demonstrated that the ratio of nuclear radii to cytoplasm radii decreased in the cell in PCNA positive expressing nodules. In addition, the nodules showed by P-GST expressed higher PCNA than those the foci expressed, indicating an increased possibility to develop further in the nodules.

CONCLUSION

PCNA expression may be used as a relatively ideal marker for predicting the potential development of precancerous lesions in the experimental model of rat liver cancer induction.

Unusual conformational changes in 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase as revealed by X-ray crystallography and NMR

The crystal structure of Escherichia coli 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase (HPPK) in complex with MgADP has been determined at 1.5-A resolution with a crystallographic R factor of 0.191. The solution structure of HPPK in complex with Mg(2+) and beta,gamma-methyleneadenosine 5'-triphosphate (MgAMPPCP) has been determined using a simulated annealing protocol with 3,523 experimental NMR restraints. The root mean square deviation of the ensemble of 20 refined conformers that represent the solution structure from the mean coordinate set derived from them is 0.74 +/- 0.26 A for all backbone atoms and 0.49 +/- 0.22 A when residues Pro(14), Pro(44)-Gln(50), and Arg(84)-Pro(91) are excluded. Binding of MgADP causes significant changes in the conformation and dynamical property of three loops of HPPK that are involved in catalysis. A dramatic, unusual conformational change is that loop 3 moves away from the active center significantly with some residues moving by >17 A. The binding of MgADP also stabilizes loop 1 and loop 3 but makes loop 2 more mobile. Very similar conformational and dynamical changes are observed in the NMR solution structure of HPPK.MgAMPPCP. The conformational and dynamical changes may play important roles in both substrate binding and product release in the catalytic cycle.

[Bcl-2, p53 expression and Epstein-Barr virus infection in primary nasopharyngeal carcinoma]

OBJECTIVE

To observe bcl-2, p53 gene expression and Epstein-Barr virus (EBV) infection and their relationship with clinicopathologic factors in primary nasopharyngeal carcinoma (NPC).

METHOD

p53, bcl-2 proteins were assayed with immunohistochemical technique and EBV were assayed with polymerase chain reaction in 54 cases of NPC and 13 cases of chronic inflammation of nasopharyngeal epithelium (CINE).

RESULT

The expression of p53, bcl-2 proteins and EBV were found respectively in 1(7.7%), 3(23.1%) and 1(7.7%) of 13 CINEs, which were significantly lower than those in 54 NPCs with respectively 41(75.9%), 48(88.9%) and 47(87%) (P < 0.01). In 39 cases of 54(72.2%) NPCs, we could find simultaneous p53, bcl-2 expression and EBV infection, furthermore, p53 and bcl-2 expression were significantly positively correlated with each other (r = 0.78, P < 0.01). p53 gene expression was significantly correlated with cervical lymph node metastasis of NPCs (P < 0.01). The expression of p53 in stage II, III, IV (92.9%, 78.9% and 100% respectively) were significantly higher than that in stage I (38.5%) (P < 0.01).

CONCLUSION

The expression of p53, bcl-2 gene and EBV infection are the useful factors in the diagnosis of NPC, the overexpression of p53 is related with the stage and cervical lymph node metastasis of NPC, all the three play important roles in the pathogenesis of nasopharyngeal carcinoma.

Emergency contraception with Multiload Cu-375 SL IUD: a multicenter clinical trial

The objectives of the present study were to evaluate the efficacy and side effects and the benefits and limitations of inserting Multiload intrauterine device (IUD) for emergency contraception. A total of 1013 women requesting emergency contraception was recruited, among whom 843 were parous women and 170 nulliparous women. Multiload Cu-375 SL IUD was inserted within 120 h after unprotected intercourse. A urine test for pregnancy was performed before IUD insertion to rule out pregnancy. Participants were followed-up until 1 week after the expected day of the next menstruation. Pregnancy test or ultrasound scanning were performed if menstruation did not return. Efficacy of preventing unplanned pregnancy was calculated. Efficacy and side effects were compared between the parous and nulliparous groups. The results showed that there were two pregnancies, one in each group. The pregnancy rate was 0.2 per 100 women. The efficacy rate of preventing unwanted pregnancy in the parous group was 98.1% and in the nulliparous group 92.4%. The difference was not significant. Removal of IUD because of pain and bleeding was 2.5% in parous women, but was more in the nulliparous group (10.6%). After the return of menstruation, 95.7% of parous women and 80% of nulliparous women maintained the IUD for contraception. There were two complete expulsions and three partial expulsions of the IUD, but there was no significant changes in menstruation and bleeding pattern, nor was infection or trauma observed. It was concluded that IUD insertion is a safe and effective method for emergency contraception for both parous and nulliparous women. One of the advantages of using an IUD is its long-term contraceptive effect, if the women prefer to continue its use.

[Study of delayed encephalopathy after acute carbon monoxide poisoning by clinical characteristic, CT and MRI features]

OBJECTIVE

To explore the diagnosis value of CT and MRI in delayed encephalopathy after acute carbon monoxide poisoning (DEACMP).

METHODS

The clinical, CT and MRI data of 20 patients with DEACMP were analysed.

RESULTS

The main clinical manifestations of the disease were intellectual disturbances and personality disorders. CT scan in DEACMP showed that some characteristic changes (such as diffuse low density) was observed within bilateral cerebral white matter, prominently within bilateral or unilateral globus pallidus or basal ganglia areas. The MRI showed that brain lesions in DEACMP were bilateral symmetric punctate, spotty or confluent foci within periventricular white matter and centrum semioval, which showed high signal intensity in T2-weighted and low signal intensity in T1-weighted. The chronic ischemia changes were found in the globus pallidus or basal ganglia areas. Cerebral cortex lesions were observed occasionally.

CONCLUSIONS

The diagnosis of DEACMP mainly depends on case history, clinical features and neuroradiological presence. MRI is more valuable in the diagnosis and the differential diagnosis than CT.

Agonist-independent activation of metabotropic glutamate receptors by the intracellular protein Homer

G-protein-coupled receptors (GPCRs) transduce signals from extracellular transmitters to the inside of the cell by activating G proteins. Mutation and overexpression of these receptors have revealed that they can reach their active state even in the absence of agonist, as a result of a natural shift in the equilibrium between their inactive and active conformations. Such agonist-independent (constitutive) activity has been observed for the glutamate GPCRs (the metabotropic glutamate receptors mGluR1a and mGluR5) when they are overexpressed in heterologous cells. Here we show that in neurons, the constitutive activity of these receptors is controlled by Homer proteins, which bind directly to the receptors' carboxy-terminal intracellular domains. Disruption of this interaction by mutagenesis or antisense strategies, or expression of endogenous Homer1a (H1a), induces constitutive activity in mGluR1a or mGluR5. Our results show that these glutamate GPCRs can be directly activated by intracellular proteins as well as by agonists.

[An experimental study of effects of injection of pingyangmycin on activities of enzyme of endothelial cells]

OBJECTIVE

The objective of this study is to investigate the mechanism of acute trauma of endothelium after injection of Pingyangmycin.

METHODS

A total of 42 adult Wistar rats were divided randomly into experimental groups (24), positive control groups (12) and normal control group (6), and the rats in the experimental or the positive control groups were injected with Pingyangmycin or sodium morrhuate into the mesenteric veins respectively, and then the enzyme activity of hepatic endothelial cells and hepatocytes was examined histochemically 0.5, 1, 2, 4, 8 and 24 hours after injection.

RESULTS

After injection, the activity of 5'-nucleinase(5'-N) in hepatic endothelial cells and that of lactic dehydrogenase (LDH) and succinodehydrogenase (SDH) in hepatocytes decreased gradually, but that injected Pingyangmycin was less than that injected sodium morrhuate.

CONCLUSION

The trauma caused by Pingyangmycin is less than that caused by sodium morrhuate, but the reaction of trauma caused by both is nonspecific.

[A study of survival motor neuron and neuronal apoptosis inhibitory protein gene in spinal muscular atrophy]

OBJECTIVE

To study the absence of survival motor neuron(SMN) gene exon 7,8 and neuronal apoptosis inhibitory protein(NAIP) gene exon 5,6 in Chinese patients with type I - IV spinal muscular atrophy (SMA) and to confirm the relationship between the deletions of SMN, NAIP and SMA phenotype.

METHODS

PCR and PCR-enzyme methods were used to detect the deletions of NAIP gene exon 5,6 and SMN gene exon 7,8 in 45 SMA (I - IV) patients and 30 healthy relatives of the patients and 30 normal controls.

RESULTS

Deletions of exon 7 and 8 of the telomeric SMN gene were 4/4, 2/3, 1/8 and 0/30 in type I, II, III and IV SMA patients, respectively. One patient with type II lacked the exon 7 but retained exon 8. No deletions was found in the relatives and controls(0/60). No deletions of exon 5 and 6 of the NAIP gene was detected in all the patients, healthy relatives and controls.

CONCLUSIONS

Deletions of SMN gene exon 7 and 8 exa mined by PCR-enzyme digestion could be recommended as an accurate gene diagnostic method for SMA with type I and II. However, the method was not as useful in type III as in I and II for making a diagnosis of SMA. Type IV SMA, a heterogeneous disease with phenotypical similarities to type I - III SMA, may be caused by deletion of other genes. The frequency of NAIP deletion was lower in Chinese SMA patients.

[A clinical evaluation on reconstruction in extended partial laryngectomy for transglottic cancer]

OBJECTIVE

Transglottic cancer has been a definite indication for total laryngectomy in decades, compromising function of the larynx. The purpose of this study is to present a new radical surgery of extended partial laryngectomy and reconstruction to restore the essential function of larynx.

METHODS

Forty-one cases of transglottic cancer were treated by extended vertical laryngectomy (26/41), extended frontolateral laryngectomy (5/41) and subtotal laryngectomy (10/41); the defects of larynx were reconstructed by rotary door myocutaneous flap in twenty-seven cases, by sternohyoideus flap in seven cases, by osteomuscular flap in five cases and by sternocleidomastoid flap in two cases.

RESULTS

The 3 and 5 year survival rates were 85.7% (30/35) and 74.1% (20/27) respectively, those for stage III were 84.6% (22/26) and 76.2% (16/21), for stage IV were 3/4 and 1/2 respectively. All cases resumed acceptable voice, 92.7% (38/41) and enjoyed satisfactory phonation. The over-all decannulation rate was 87.8% (36/41), those with rotary door myocutaneous flap was 96.3% (26/27), with sternohyoideus flap was 5/7, with osteomuscular flap was 4/5 and with sternocleidomastoid flap was 1/2. All patients had normal swallow function.

CONCLUSION

Extended partial laryngectomy is a kind of radical operation in selected cases of transglottic cancer. The method of reconstruction with rotary door myocutaneous flap can improve curative effect and the essential functions of the larynx.