Bizarre presentation of choriocarcinoma: A case report / Philippine Journal of Obstetrics and Gynecology

@#Choriocarcinoma is a malignant subtype of gestational trophoblastic disease that follows any type of pregnancy. It is characterized by rapid hematogenous spread to multiple organs, associated with high human chorionic gonadotropin levels with good response to chemotherapy. We present the case of a 31‑year‑old Filipina who initially presented with severe headaches and blurring of vision 3 years after an unremarkable term pregnancy. The transvaginal ultrasound was normal. After a series of diagnostic tests, the initial working impression was a primary brain tumor with metastases to the lungs, adrenal, kidney, and vulva. Emergency craniotomy was done due to deteriorating status secondary to an intracranial hemorrhage. The histopathology report showed choriocarcinoma. Chemotherapy using Etoposide‑Methotrexate‑Actinomycin D‑Cyclophosphamide‑Vincristine with high‑dose methotrexate and concomitant whole‑brain irradiation was then instituted with good response. This case highlights the importance of having a high index of suspicion for gestational trophoblastic neoplasia to prevent the performance of unnecessary procedures, leading to a delay in diagnosis and the institution of the appropriate treatment.

Super-sensitive bifunctional nanoprobe: Self-assembly of peptide-driven nanoparticles demonstrating tumor fluorescence imaging and therapy

The development of nanomedicine has recently achieved several breakthroughs in the field of cancer treatment; however, biocompatibility and targeted penetration of these nanomaterials remain as limitations, which lead to serious side effects and significantly narrow the scope of their application. The self-assembly of intermediate filaments with arginine-glycine-aspartate (RGD) peptide (RGD-IFP) was triggered by the hydrophobic cationic molecule 7-amino actinomycin D (7-AAD) to synthesize a bifunctional nanoparticle that could serve as a fluorescent imaging probe to visualize tumor treatment. The designed RGD-IFP peptide possessed the ability to encapsulate 7-AAD molecules through the formation of hydrogen bonds and hydrophobic interactions by a one-step method. This fluorescent nanoprobe with RGD peptide could be targeted for delivery into tumor cells and released in acidic environments such as endosomes/lysosomes, ultimately inducing cytotoxicity by arresting tumor cell cycling with inserted DNA. It is noteworthy that the RGD-IFP/7-AAD nanoprobe tail-vein injection approach demonstrated not only high tumor-targeted imaging potential, but also potent antitumor therapeutic effects in vivo. The proposed strategy may be used in peptide-driven bifunctional nanoparticles for precise imaging and cancer therapy.

A spectrum of gestational trophoblastic neoplasia

Gestational trophoblastic disease is a spectrum of diseases caused by overgrowth of chorionic villi of placenta. They range from most Benign to most Malignant. Those with local invasion or metastasis are labelled as Gestational trophoblastic Neoplasia (GTN). We have conducted a retrospective observational study of various Gestational trophoblastic neoplasias (GTN) at NRIGH for a period of 3 years, out of which, one example of each variety is being presented. All these varieties have been successfully treated and all the patients are under follow up.

Antimicrobial activity of actinomycetes and characterization of actinomycin-producing strain KRG-1 isolated from Karoo, South Africa

In the present study we reported the antimicrobial activity of actinomycetes isolated from aridic soil sample collected in Karoo, South Africa. Eighty-six actinomycete strains were isolated and purified, out of them thirty-four morphologically different strains were tested for antimicrobial activity. Among 35 isolates, 10 (28.57%) showed both antibacterial and antifungal activity. The ethyl acetate extract of strain KRG-1 showed the strongest antimicrobial activity and therefore was selected for further investigation. The almost complete nucleotide sequence of the 16S rRNA gene as well as distinctive matrix-assisted laser desorption/ionization-time-of-flight/mass spectrometry (MALDI-TOF/MS) profile of whole-cell proteins acquired for strain KRG-1 led to the identification of Streptomyces antibioticus KRG-1 (GenBank accession number: KX827270). The ethyl acetate extract of KRG-1 was fractionated by HPLC method against the most suppressed bacterium Staphylococcus aureus (Newman). LC//MS analysis led to the identification of the active peak that exhibited UV-VIS maxima at 442 nm and the ESI-HRMS spectrum showing the prominent ion clusters for [M-H2O+H]+ at m/z 635.3109 and for [M+Na]+ at m/z 1269.6148. This information could be assigned to chromopeptide lactone antibiotic - actinomycin. Our results suggest that unexplored soils could be an interesting source for exploring antibacterial secondary metabolites.

Chemotherapy outcome of patients with choriocarcinoma / Монголын Анагаах Ухаан

Background: Choriocarcinoma 15-20 new cases per year diagnosed at National Cancer Center of Mongolia. Due to insufficient necessary new drugs for choriocarcinoma patients, cancer center cannot provide the most useful treatment EMA/CO so patients were treated MAC or metothrexate, Adriamycin and cyclophosphamide. The outcomes of patients with choriocarcinoma treated with combined chemo drugs never been studied in Mongolia. Goal: To evaluate the results of combined chemotherapy in choriocarcinoma at National Cancer Center of Mongolia. Methods: Retrospective cohort review of 42 patients with choriocarcinoma who treated with MAC combination chemotherapy at NCC of Mongolia during 2004-2007. Based on MAC ppatients charts we evaluated clinical characteristics, level of HCG during treatment cycles, ultrasound changes and other lab tests. Results: We treated 42 patients with choriocarcinoma from 2004 through 2007. All patients were treated with MAC combination chemotherapy at NCC. The number of cases with choriocarcinoma is increasing in each year. 37.5% of these patients were aged between 30-34 years old, so it shows maximum incidence occurs during child bearing years. The most common clinical characteristics were 44% bleeding, 32% lower abdominal quadrant pain related to disease stages, 36% cough, and 28% fever. Out of 42 patients 35% of them had lung metastasis which was significantly different than other gynecological cancer metastasis. Conclusion: MAC combination treatment offers long-term disease-free survival and potential cure in patients with choriocarcinoma. The reported median survival in these group patients is 5 years. Importantly, 56% of patients were lived up to 5 years in remission.

Production of actinomycin-D by the mutant of a new isolate of Streptomyces sindenensis / Produção de actinomicina-D por um mutante de uma nova cepa de Streptomyces sindenensis

An actinomycin-D producing strain was isolated from soil and characterized as Streptomyces sindenensis. The culture was subjected to UV irradiation and a mutant with 400 percent higher actinomycin-D production was isolated (400 mg/l-1 as compared to 80 mg/l-1 produced by the parent). Production medium was optimized and antibiotic yield with the mutant was enhanced to 850 mg/l-1 which is 963 percent higher as compared with the parent.

Uma cepa produtora de actinomicina-D foi isolada de solo e caracterizada como Streptomyces sindenensis. A cultura foi submetida à radiação UV, e um mutante capaz de produzir 400 por cento mais actinomicina-D foi isolado (400mg/L comparado a 80mg/L produzido pela cepa parental). O meio de produção do antibiótico foi otimizado e o rendimento aumentou para 850 mg/L, ou seja, 963 por cento mais alto que a cepa parental.

Roles of HSP 70 in Actinomycin D-Induced Inhibition of Proliferation and Apoptosis in Lung Adenocarcinoma Cell / 生物化学与生物物理进展

It had been proved by many evidences that several heat shock proteins (HSPs) expression is up-regulated in tissue-derived primary lung cancer, and HSPs may play important roles in development, in resistant to drugs and in prognosis of lung cancer. However, there have not still systemic research on which HSPs,especially HSP70 can be or not thought as a new biological target in the therapy to lung cancer. In order to address the expression and roles of heat shock protein 70 (HSP70) in lung adenocarcinoma, immunoblotting was performed to detect the expression of HSP70 in tissue specimens from lung adenocarcinoma which were diagnosed unambiguously by branch fibromicroscopy and were excised. It showed that in the normal lung tissues, the expression of HSP70 was less then that in cancer tissues. After down-regulation of HSP70 protein by HSP70 anti-sense oligonucleotides in A549 cell line, MTT assay showed that the proliferation of A549 cells was inhibited remarkably after the treatment with HSP70 antisense oligonucleotides and Act D. There had significant differential in HSP70 antisense treatment group followed by Act D treatment and Act D treatment group. Results of Hoechst33258 staining revealed that HSP70 antisense oligonucleotides could promote Act D-mediated apoptosis in A549 cells with a higher percentage of apoptotic cells (26.91?3.73)% than that of Act D-treated group (16.83?3.41)% (P

Expression of Complement C3a Receptor and C5a Receptor by A(beta)(1-42) Stimulated Human Neuroblastoma Cell Line

BACKGROUND: Complementary receptors have been suggested to play causative roles in the neuroinflammatory process of Alzheimer's disease (AD). The genetic expressions of the C3a receptor (C3aR), C5a receptor (C5aR) and the protein expressions of the C3aR and C5aR were examined in the human neuroblastoma cell line, SK-N-SH, after the administration of amyloid peptide (A1-42). METHODS: SK-N-SH cells were incubated overnight with a single dose of 20 M of aggregated A (A1-42). An inhibition study was done with actinomycin D (ActD, 2.5 M) or with the administration of cycloheximide (CHX, 2.5 M) to the cell suspension. Messenger RNA expressions of C3aR and C5aR were detected by RT-PCR. The intensity of bands from 6% polyacrylamide electrophoretic gel was analyzed by a bioimage analyzer. The protein production of C3aR and C5aR in the A-treated cells was also measured by flow cytometry. NFB activation after treatment of A in the cells was detected by an electrophoretic mobility-shift assay. RESULTS: A1-42 increased the expression of C3aR and C5aR. ActD inhibited the expression of both anaphylatoxin receptors but CHX only suppressed C5aR mRNA expression. Activated NFB was demonstrated in the A-stimulated cells. CONCLUSIONS: C3aR and C5aR were constitutively expressed in the human neuroblastoma SK-N-SH cell. Expression of these anaphylatoxin receptors was upregulated after A1-42 stimulation, which as a result, may contribute to the complement-mediated neuroinflammation of AD.

Hepatic Veno-occlusive Disease after Combination Chemotherapy with Vincristine, Actinomycin-D, Cyclophosphamide: Successful Treatment with Glutathione and Vitamin E / 대한소아혈액종양학회지

Hepatic veno-occlusive disease (VOD) is characterized by the narrowing or fibrous obliteration of terminal hepatic venules and small sublobular veins. The obliteration of blood flow may lead to tender hepatomegaly, ascites, hepatocellular necrosis, and possibly encephalopathy. Hepatic VOD is a well described complication after allogeneic and autologous stem cell transplantation (SCT) for malignancy. The intergroup rhabdomyosarcoma study (IRS) group has extensively used the combination chemotherapy of vincristine, actinomycin-D, and cyclophosphamide (VAC) for the treatment of rhabdomyosarcoma and hepatic VOD was rarely reported after the administration of VAC chemotherapy. We report a case of severe hepatic VOD which occurred in a 7 year-old boy with stage III rhabdomyosarcoma after VAC chemotherapy according to IRS-IV regimen. He developed persistent thrombocytopenia, tender hepatomegaly, jaundice, weight gain due to ascites and generalized edema, and was treated successfully with N-acetylcysteine, nitrate, green tea polyphenol, glutathione and vitamin E.

Expression of Complement Regulator Genes in Abeta1-42 Stimulated Human Neuroblastoma Cell

BACKGROUND: Endogenous complement inhibitors in the brain may protect against the neuroinflammation in Alzheimer's disease. Human neuroblastoma cells were stimulated by Abeta1 - 4 2 to investigate whether the expression of various complement regulator genes is upregulated. METHODS: SK-N-SH cells were incubated overnight with a single dose of 20 microM of Abeta1-42 or 0.5 ng/ml - 5 ng/ml of TNFalpha or both. Actinomycin D (2.5 microM) or cycloheximide (2.5 microM) was also added to the cell suspension. Messenger RNA expression of decay accelerating factor (DAF), membrane cofactor protein (MCP), CD59, complement-receptor 1(CR1), C1 inhibitor (C1-INH), C4-binding protein, factor H, factor I, clusterin and S-protein was measured by RT-PCR. RESULTS: Abeta1-42 and TNFalpha upregulated the expression of C1- INH significantly but increased expression of mRNA for factor H was not statistically significant. The expression of mRNAs for DAF and MCP was at low a level after stimulation. Factor I, CD59 and clusterin were not changed in their mRNA level. The mRNAs for S-protein, C4-binding protein and CR1 were not detected. Actinomycin D suppressed mRNA levels of C1-INH and CD59 significantly. Cycloheximide also inhibited the expression of both C1-INH and CD59. CONCLUSIONS: Early upregulated expression of C1-INH in Abeta1-42 stimulated neuroblastoma cell may contribute to a host defense mechanism against complement-mediated neuronal cell damage.

Expression of Complement Regulator Genes in Abeta1-42 Stimulated Human Neuroblastoma Cell

BACKGROUND: Endogenous complement inhibitors in the brain may protect against the neuroinflammation in Alzheimer's disease. Human neuroblastoma cells were stimulated by Abeta1 - 4 2 to investigate whether the expression of various complement regulator genes is upregulated. METHODS: SK-N-SH cells were incubated overnight with a single dose of 20 microM of Abeta1-42 or 0.5 ng/ml - 5 ng/ml of TNFalpha or both. Actinomycin D (2.5 microM) or cycloheximide (2.5 microM) was also added to the cell suspension. Messenger RNA expression of decay accelerating factor (DAF), membrane cofactor protein (MCP), CD59, complement-receptor 1(CR1), C1 inhibitor (C1-INH), C4-binding protein, factor H, factor I, clusterin and S-protein was measured by RT-PCR. RESULTS: Abeta1-42 and TNFalpha upregulated the expression of C1- INH significantly but increased expression of mRNA for factor H was not statistically significant. The expression of mRNAs for DAF and MCP was at low a level after stimulation. Factor I, CD59 and clusterin were not changed in their mRNA level. The mRNAs for S-protein, C4-binding protein and CR1 were not detected. Actinomycin D suppressed mRNA levels of C1-INH and CD59 significantly. Cycloheximide also inhibited the expression of both C1-INH and CD59. CONCLUSIONS: Early upregulated expression of C1-INH in Abeta1-42 stimulated neuroblastoma cell may contribute to a host defense mechanism against complement-mediated neuronal cell damage.

Induction of Various Pro-inflammatory Mediators and Their Receptors in Human Astrocytoma Cell Line Stimulated by beta-amyloid Protein

BACKGROUND: The induction of production and production inhibition of alpha1-antichymotrypsin (ACT), IL-1 alpha, IL-1 alpha receptor and macrophage inflammatory protein-1 (MIP-1) receptor in A beta1-42 (A beta)-stimulated U373MG cell, the human astrocytoma cell line, have never been reported. METHODS: U373MG cells (1 x 10(6) cells in RPMI-1640 media) were incubated for overnight after administration of a single dose of 20 micro M of A beta or 0.5 ng/ml of TNF alpha or both. Actinomycin D (2.5 micro M) or cycloheximide (2.5 micro M) was also added to the cell suspension. Messenger RNA expression of ACT, IL-1 alpha, IL-1 alpha receptor and MIP-1 receptor was measured by RT-PCR. Western blot was done and nitrocellulose paper was stained with anti-ACT and anti-GFAP antibody. NF kappa B activation after treatment of A beta in U373MG cells was detected by electrophoretic mobility-shift assay. RESULTS: A beta and TNF alpha both increased production of ACT in a dose-dependent manner. TNF alpha enhanced A beta-induced mRNA had increases of ACT, IL-1 alpha, IL-1 alpha receptor and MIP-1 alpha receptor. Activated NF kappa B was demonstrated in the A beta, TNF alpha-stimulated U373MG cells. Actinomycin suppresses mRNA level of ACT and IL-1 alpha receptor but cycloheximide inhibits the expression of ACT, IL-1 alpha and MIP-1 alpha receptor. CONCLUSIONS: TNF alpha increases synthesis of ACT, IL-1 alpha, IL-1 alpha receptor and MIP-1 alpha receptor in A beta-stimulated astrocyte, which, as a result, may contribute to the neuroinflammation of Alzheimer's disease.

The treatment of bladder tumors by the intravesical instillation of thio-TEPA or of actinomycin D

Thio-TEPA weekly instillations of 30-60 mg. in 30-60 ml. of sterile water or saline were employed in 20 patients with bladder papilloma or various stages of bladder carcinoma. Two of 6 patients with papilloma showed complete disappearance of the tumor after an average of 8 instillations and two of six (2/6) patients with papilloma showed partial destruction of the tumor. In 10 patients with deeply infiltrating cancers practically no response was observedActinomycin D was employed in 7 patients using a weekly topical dose of 1.0 mg. in 30 ml. of sterile water or saline. In the four patients with papilloma, one showed necrotic changes without apparent decrease in size of the tumor. In no instance was disappearance of a papilloma observedAs employed in this series, topical actinomycin D instillation for bladder tumor was of no value. Topical thio-TEPA may be useful for patients who are poor surgical risks and for patients whose lesions are diffuse and not amendable to surgical attack less than a cystectomy. For solitary or few papillary tumors conventional methods of transurethral treatment are preferable. (Summary)

Adherence and experimental infection of bacteria associated with periodontal infections of young cattle in Brazil ("Cara inchada")

In vitro- and in vivo-assays were conducted, to study the possible role of streptomycin- and actinomycin-producing soil actinomycetes for the pathogenesis of "Cara inchada" in cattle (CI). Adherence of Bacteroides spp. to epithelial cells of the bovine gingiva, known to be associated with the progressive lesions of CI, was significantly increased by the addition of streptomycin, actinomycin or antibiotic culture supernatants of the soil actinomycetes. Applications of these mixtures together with Actinomyces pyogenes to the marginal gingiva of the upper premolar teeth of about 1 month old Holstein Friesian calves did not lead to progressive lesions of CI. Only one calf exhibited a slight diarrhea and a temporary retraction of the gingiva at the site of application.

Foram realizados ensaios in vitro e in vivo para estudar o possível envolvimento de actinomicetos do solo como produtores de estreptomicina e actinomicina na pathogênese da periodontite da ,,cara inchada" dos bovinos (CI). A aderência de Bacteroides spp. às células epitheliais da gengiva marginal de bezerros, dos quais se sabe estarem associados às lesões progressivas da CI, aumentou significantivamente através a adição de estreptomicina, actinomicina ou de antibióticos produzidos pelo cultivo de actinomicetos do solo. Aplicações de Bacteroides spp. e Actinomyces pyogenes, junto com os antibióticos, na gengiva dos dentes premolares maxilares de bezerros da raça holandês preto-branco, de cerca de 1 mês de idade, não provocaram lesões progressivas da CI. Somente um bezerro mostrou leve diarréia e retração temporária da gengiva no local da aplicação.

Simultaneous Three Color Detection of Surface Antigen (My 7), Intracellular Antigen (c-myc), and DNA Content using Single Laser Flow Cytometry / 대한산부인과학회잡지

Flow cytometry, a useful tool for measuring DNA content and cell differentiation as expressed by cell surface markers, is utilized to measure multiple antigens, especially surface antigen, intracellular oncoprotein, and DNA content, simultaneously. For this simultaneous detection, several methods off ixation and permeabilization have been used with limited values. In this study, 20 ng/ml of lysolecithin in 1% paraformaldehyde solution was utilized for fixation and permeabilization of cultured promyelocytic leukemic cells(HL 60). The cells were first stained with phycoerythrin (PE)-conjugated monoclonal antibody to the cell surface My 7 antigen and then were fixed and permeabilized with 20 ng/ml of lysolecithin in 1% partormaldehyde solution. After incubation, the fixed and permeabilized cells were stained with monoclonal antibody to intracellular c-myc antigen, which were followed by fluorescein isothiocyanate (FITC)-conjugated secondary antibody. The c-myc stained cells were finally stained for DNA content with 7-amino-actinomycin D(7-AAD). This procedure permits excellent staining for intracellular oncoproteins and preservation of surface antigens with relatively low cofficients of variation (CV) for the G0G1 peak of the DNA histograms and suggests that the sequential staining procedure of surface antigen, intracellular antigen, and DNA content will be extended for the study of correlations with cellular differentiation, expression of oncoproteins, and cell cycle analysis in the cells which are obtained from human malignant diseases using a 488 nm single laser flow cytometry.

Effects of actinomycin D and cycloheximide on gonadotropin- or 17α., 20β-dihydroxy-4- pregnen-3-one-induced in vitro maturation in oocytes of the catfish, Clarias batrachus.

The effect of inhibitors in the oocyte maturation of Clarias batrachus, was investigated in vitro using actinomycin D and cycloheximide. Full-grown immature oocytes incubated with salmon gonadotropin (SG-G100) and 17α, 20ß-dihydroxy-4-pregnen-3-one at the concentration of 1 μg/ml induced 86·0 ± 1·2% and 91·3 ± 2·4% of germinal vesicle breakdown, respectively. When the oocytes were incubated with SG-G100 (1 μg/ml) + different concentrations of actinomycin D or cycloheximide, a significant drop in the frequency of germinal vesicle breakdown was observed. Thus, gonadotropin-induced maturation was inhibited by both transcriptional and translational inhibitors. When the oocytes were incubated with 17α, 20ß-dihydroxy-4-pregnen-3-one (1μg/ml) + different concentrations of cycloheximide, a significant inhibition of germinal vesicle breakdown was recorded. However, the maturation was not inhibited when the oocytes were incubated in the presence of 17α, 20ß-dihydroxy-4-pregnen-3-one (1 μg/ml) and different concentrations of actinomycin D. This suggests that mRNA synthesis is not obligatory for 17α, 20β- dihydroxy-4-pregnen-3-one induced oocyte maturation. Based on the time course experiment, it was observed that the inhibition of maturation in cycloheximide treated oocytes extends up to 12 h after which the effect becomes slowly subdued.

Synthesis of actinomycin-insensitive RNA during the first postirradiation mitotic cycle, in the synchronously mitotic plasmodia of Physarum polycephalum.

A sucrose density gradient analysis of 3H-uridine pulse-labelled RNA from the first postirradiation mitotic cycle of Physarum polycephalum shows that all the density classes of RNA synthesized during this period are resistant to the peptide-antibiotic, actinomycin D. In fact, the synthesis is found to be greater in the presence of the drug. The heterogenously sedimenting synthetic activity here may represent a single species of RNA and its precursors or more than one kind of RNA. Further characterization of this RNA is meaningful in view of the actinomycin insensitivity of the postirradiation mitotic cycle itself to this antibiotic.

The protective effect of heat shock gene expression against hydrogen peroxide一induced pulmonary endothelial cells injury / 中国病理生理杂志

To ascertain whether heat shock gene expression could protect pulmonaryendothelial cell from hydrogen peroxide(H2O2)一indueed injury,the protective effect of HSPgene expression induced by pretreatment of bovine pulmonary endothelial eells(BPAECs)by heat shock (42 ℃, 2h)against lethal dose(lmmol?L(-1),45min) of H2O2一induced cyt-otoxieity was observed in vitro.It was found that BPAECs heat一shocked prior to exposureto H2O2(Immol?L(-1) 45min)showed significant decrease in H2O2一mediated incrementof LDH rdlease and TBARS production and had an obvious alleviation of H2O2一induccddecreased activities of catalase and superoxide dismutase. Further study showed thatcycloheximide, a protein synthesis inhibitor and Actinomycin D,a mRNA transcriptioninhibitor blocked the expression of HSP 70 and HSP 70 mRNA respectively.Both agentsprevented the cytoprotective effect of heat shock pretreatment against H2O2一mediatedBPAECs injury. The results suggested that HSP70 gene selectively translated after heat shockwas invoived in enhancement of eellular antioxidant mechanism and protected BPAECsagainst H2O2一induced injury

INHIBITORY EFFECTS OF ACTINOMYCIN 23-21 ON TRANSPLANTED TUMORS OF HUMAN NASOPHARYNGEAL CARCINOMATOUS CELLS AND GASTRIC CARCINOMATOUS CELLS IN NUDE MICE / 中国药理学通报

Actinomycin 23-21 ( ACT 23-21 ) is an anticancer antibiotic of Actinmycines. This antibiotic was produced from soil Streptomyces flaveolus which was isolated and obtained from soil samples in Fuzhou, China.The effects of ACT 23-21 were observed on using 2 transplanted models of human nasophryangeal carcinomatous cells ( CNE-2Z ) and human gastric carcinomatous cells ( MGc-803 ) in nude mice. At ACT 23-21 50?g/kg, the inhibition rate for transplanted tumors of CNE-2Z and MGc-803 were 58.4% (P

Structural and mode of action studies on bio-active molecules.

The technique of nuclear Overhauser effect difference spectroscopy allows the determination, from 1H nuclear magnetic resonance spectra, of those protons in a structure which are near in space to a selected, irradiated proton. The experiment is extremely powerful in the determination of structure in solution, and is sufficiently precise often to give stereochemical detail. The method was used in determination of the structures of the antibiotics of the teicoplanin complex (members of the vancomycin group), and the principles are briefly illustrated. Additionally, nuclear magnetic resonance pulse sequences can be used to edit 13C spectra (separate the spectrum into four spectra, containing C, CH, CH2, and CH3 carbons), and this technique also aided the structure elucidation of the teicoplanin complex. Finally, it is emphasised that nuclear Overhauser effect difference spectroscopy can be used to determine the molecular details of drug binding sites, and an example is given.