Rapid, high-sensitivity detection of biomolecules using dual-comb biosensing

Rapid, sensitive detection of biomolecules is important for biosensing of infectious pathogens as well as biomarkers and pollutants. For example, biosensing of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still strongly required for the fight against coronavirus disease 2019 (COVID-19) pandemic. Here, we aim to achieve the rapid and sensitive detection of SARS-CoV-2 nucleocapsid protein antigen by enhancing the performance of optical biosensing based on optical frequency combs (OFC). The virus-concentration-dependent optical spectrum shift produced by antigen-antibody interactions is transformed into a photonic radio-frequency (RF) shift by a frequency conversion between the optical and RF regions in the OFC, facilitating rapid and sensitive detection with well-established electrical frequency measurements. Furthermore, active-dummy temperature-drift compensation with a dual-comb configuration enables the very small change in the virus-concentration-dependent signal to be extracted from the large, variable background signal caused by temperature disturbance. The achieved performance of dual-comb biosensing will greatly enhance the applicability of biosensors to viruses, biomarkers, environmental hormones, and so on.

Cartilage wear patterns in severe osteoarthritis of the trapeziometacarpal joint: a quantitative analysis

OBJECTIVE

The present quantitative study aimed to assess the three-dimensional (3-D) cartilage wear patterns of the first metacarpal and trapezium in the advanced stage of osteoarthritis (OA) and compare cartilage measurements with radiographic severity.

DESIGN

Using 19 cadaveric trapeziometacarpal (TMC) joints, 3-D cartilage surface models of the first metacarpal and trapezium were created with a laser scanner, and 3-D bone surface model counterparts were similarly created after dissolving the cartilage. These two models were superimposed, and the interval distance on the articular surface as the cartilage thickness was measured. All measurements were obtained in categorized anatomic regions on the articular surface of the respective bone, and we analyzed the 3-D wear patterns on the entire cartilage surface. Furthermore, we compared measurements of cartilage thickness with radiographic OA severity according to the Eaton grading system using Pearson correlation coefficients (r).

RESULTS

In the first metacarpal, the cartilage thickness declined volarly (the mean cartilage thickness of the volar region was 0.32 ± 0.16 mm, whereas that of the dorsal region was 0.53 ± 0.18 mm). Conversely, the cartilage evenly degenerated throughout the articular surface of the trapezium. Measurements of the categorized regions where cartilage thinning was remarkable exhibited statistical correlations with radiographic staging (r = -0.48 to -0.72).

CONCLUSIONS

Our findings indicate that cartilage wear patterns differ between the first metacarpal and trapezium in the late stage of OA. There is a need for further studies on cartilage degeneration leading to symptomatic OA in the TMC joint.

Altered bone density and stress distribution patterns in long-standing cubitus varus deformity and their effect during early osteoarthritis of the elbow

OBJECTIVE

To quantify the bone density and stress distribution patterns in long-standing cubitus varus and clarify the effects of the deformity on bone density.

DESIGN

We created three-dimensional computed tomography (CT) elbow models from 21 patients with long-standing cubitus varus deformities without advanced osteoarthritis (OA) and assessed the deformity by superimposing the affected humerus onto a mirror-image of the contralateral normal. Elbows were divided into 13 regions before measuring the bone density of each region and comparing the percentage of high-density volume (%HDV) between affected and normal sides. We constructed finite element models and quantitatively analyzed stress distribution.

RESULTS

Average degrees of deformities were 20.1° of varus, 6.4° of extension, and 12.7° of internal rotation. The medial side of the affected humerus and ulna, Anteromedial trochlea (P < 0.001), Medial coronoid (P = 0.004), and Medial olecranon (P = 0.049) had significantly higher %HDVs than their normal counterparts. Conversely, %HDVs on the affected lateral side, Capitellum (P < 0.001), Anterolateral trochlea (P = 0.010), Posterolateral trochlea (P < 0.001), Lateral coronoid (P = 0.007), and Lateral olecranon (P < 0.001) were significantly lower than the normal side. The affected radial head %HDVs at Anterolateral and Posteromedial quadrants were high (P = 0.007) and low (P = 0.007), respectively. The bone density distribution coincided with stress distribution patterns revealed by finite element analysis (FEA), except in the lateral region influenced by forearm rotation.

CONCLUSIONS

Repetitive stress on the medial elbow may alter bone density distribution patterns, probably presenting from early stage of OA.

Human parvovirus B19 infection mimicking systemic lupus erythematosus

Abstract Although several recent reports have discussed the similarities between human parvovirus B19 (HPV-B19) infection and systemic lupus erythematosus (SLE), the relationship between these conditions has not been established owing to the small number of patients investigated. In 1998-1999, an outbreak of Erythema infectiosum occurred close to our hospital, enabling us to investigate the clinical, hematological, and serological findings, including serum complement and antinuclear antibodies (ANA), in 22 patients with acute HPV-B19 infection. The principal symptoms included rash (86.3%), edema (59%), arthralgia (45.4%) and fever (31.8%). Lymphadenopathy was seen in three of the 22 cases. The laboratory findings showed high incidences of leukopenia (50%), hypocomplementemia (95%), and ANA (64.7%). At the time of disease onset, patients with acute HPV-B19 infection presented with features which were similar to those of SLE. The possibility of HPV-B19 infection should therefore be considered in patients presenting with SLE-like features.

Membranoproliferative glomerulonephritis associated with hypocomplementemic urticarial vasculitis after complete remission of membranous nephropathy

A 49-year-old-man developed proteinuria in 1978. He was diagnosed as having membranous nephropathy by renal biopsy and was treated with prednisolone. The proteinuria disappeared completely and the treatment was stopped. In 1995, after complete remission, he developed nephrotic syndrome with chronic urticaria and hypocomplementemia. Renal biopsy revealed membranoproliferative glomerulonephritis (type I) and skin biopsy showed leukocytoclastic vasculitis, which was compatible with hypocomplementemic vasculitis syndrome. Steroid therapy was very effective.

[Two cases of silicosis exhibiting MPO-ANCA associated disorder]

We reported two cases of silicosis exhibiting MPO-ANCA associated disorder. Case 1 was a 69 year-old man with silicosis and chronic interstitial pneumonia. He was admitted because of fever, dry cough, left chest pain, dyspnea and body weight loss. He was diagnosed as acute exacerbation of interstitial pneumonia, pericarditis and gastrointestinal bleeding. Case 2 was a 67 year-old man with silicosis. He repeated attack of fever, hoarseness, dysphagia and headache. The cell counts of cerebrospinal fluid increased and the thickness of cerebellar tent and left dura mater was observed in the brain MRI. Therefore, he was diagnosed as pachymeningitis and neuropathy of cranial nerves. Both cases were complicated by silicosis and the laboratory findings showed high serum levels of P-ANCA, ANA and rheumatoid factor and inflammatory responses, indicating they were suspected vasculitis. The two cases were treated by steroid and immunosuppressive therapy and had good clinical response. Silicosis may affect multiple organ involvement associated with P-ANCA.

Magnetic resonance imaging of pseudotumors of the craniovertebral junction in long-term hemodialysis patients

BACKGROUND/AIMS

Pseudotumors of the craniovertebral junction (PTCVJ) are observed in long-term hemodialysis (HD) patients. There are neither criteria for diagnosis nor guidelines for screening. We attempted to determine magnetic resonance imaging (MRI) findings that could be used to detect PTCVJ, to determine the prevalence of PTCVJ, and to evaluate whether destructive spondyloarthropathy (DSA) might be a yardstick for selection of patients for MRI examination for PTCVJ.

METHODS

MRI were examined in 19 DSA patients (8 males, 11 females, age 61.4 +/- 7.3 years, HD duration 17.0 +/- 4.4 years) and in 20 sex-, age-, and HD-duration-matched non-DSA patients (9 males, 11 females, age 57.5 +/- 6.6 years, HD duration 17.7 +/- 4.9 years). We evaluated MRI characteristics of PTCVJ according those which occur due to rheumatoid arthritis.

RESULTS

PTCVJ were characterized as follows: disappearance of fat pads in the upper region (supradental PTCVJ), intensity change of the 'predental triangle' in the anterior region (predental PTCVJ), and thickening of cruciform ligaments (retrodental PTCVJ). The prevalence of PTCVJ among patients undergoing HD more than 10 years was high (26 out of 39; 66.7%). The prevalence of PTCVJ was not different between DSA and non-DSA groups.

CONCLUSION

We verified that the above MRI findings might be helpful in the detection of PTCVJ. These findings were observed frequently and independently also in patients with DSA.

Efficacy of disinfectants and heat against Escherichia coli O157:H7

The bactericidal activity of disinfectants and hot water against ten Escherichia coli O157:H7 strains, which were isolated from faeces of patients with enterohaemorrhagic E. coli infection, were evaluated and showed different DNA patterns. After exposure to 0.1% benzalkonium chloride, 0.1% chlorhexidine gluconate containing a nonionic surfactant, and 80% (v/v) ethanol, 99.99% of viable bacterial cells were killed at 20 degrees C within 15 s irrespective of the presence or absence of 0.1% albumin. On the other hand, after exposure to hot water, 99.99% of the bacterial cells were killed within 15 s at 70 degrees C. These results suggest that benzalkonium chloride, chlorhexidine gluconate containing a nonionic surfactant, ethanol, and hot water at 70 degrees C or more are effective for disinfection of E. coli O157:H7 in hospitals.

A case of aberrant pancreatic cancer in the jejunum

We report a case of aberrant pancreatic cancer of the jejunum in a 63 year-old man. The patient was admitted to our hospital with epigastric discomfort and vomiting due to obstruction of the jejunum. Laparotomy revealed a submucosal tumor on the jejunum with multiple liver metastases. Histological examination showed the tumor to be a well differentiated tubular adenocarcinoma originating from aberrant pancreatic tissues lacking islets. Only 1 case of aberrant pancreatic cancer in the jejunum has been previously reported in the literature.

[Successful treatment of acute renal failure in a patient with essential mixed cryoglobulinemia using prednisolone and cryofiltration]

We report a case of acute renal failure associated with cryoglobulinemic glomerulonephritis. The patient, a 49-year-old woman, was referred to our hospital because of acute nephritic syndrome. After admission, she developed oliguria, and hemodialysis was instituted. Renal biopsy was performed and the specimens showed moderate endocapillary proliferation, large deposits filling the capillary lumen ("intraluminal thrombi"), and a double-contoured appearance, which are typical morphologic features of cryoglobulinemic glomerulonephritis. Immunoelectrophoresis showed a monoclonal increase of IgM kappa. On the basis of these findings, we diagnosed type II essential mixed cryoglobulinemia. Cryofiltration was performed with oral administration of prednisolone. Following the start of therapy, the patient's renal function gradually improved. Because of severe hypoproteinemia, cryofiltration was discontinued after three sessions. However, renal function recovered and was maintained with prednisolone only. This case shows that acute oliguric renal failure caused by cryoglobulinemic glomerulonephritis can be reversible if immunosuppressive therapy, together with plasmapheresis in more severe cases, is instituted promptly.

[A case of Grave's disease with MPO-ANCA-associated glomerulonephritis during propylthiouracil (PTU) therapy following interstitial pneumonitis]

A 68-year-old man who developed MPO-ANCA-associated glomerulonephritis during propylthiouracil (PTU) treatment is reported. In 1986, he was diagnosed as having interstitial pneumonitis. Although he tested positive for antinuclear antibody and rheumatoid factor, he had no symptoms and was followed up without therapy. Five years later, the diagnosis of Graves's disease was made after complaints of body weight loss, diplopia and exophthalmos. Tests showed positivity for anti-thyroid stimulating hormone (TSH) receptor antibody, antithyroidperoxidase antibody and antithyroglobulin antibody. He was treated with PTU and prednisolone for four years. In November 1995, hematuria and proteinuria developed, and renal function deteriorated rapidly. A renal biopsy revealed crescentic glomerulonephritis and the serum titer of MPO-ANCA was markedly elevated. He was treated with a high dose of prednisolone and cyclophosphamide. Although the serum creatinine level gradually decreased, irreversible renal dysfunction persisted. In this patient, the presence of various autoantibodies had been recognized for several years before MPO-ANCA-associated glomerulonephritis developed. Polyclonal B-cell activation and PTU treatment may have played a role in the pathogenesis of MPO-ANCA-associated glomerulonephritis.

Classification of Rickettsia tsutsugamushi in a new genus, Orientia gen. nov., as Orientia tsutsugamushi comb. nov

Recent studies of Rickettsia tsutsugamushi have demonstrated clearly the phenotypic and genotypic differences between this microorganism and other species belonging to the genus Rickettsia. Therefore, classification of R. tsutsugamushi in a new genus, Orientia gen. nov., is proposed.

The salting-out test to identify virulent Yersinia pseudotuberculosis

A total of 54 strains including 8 serotypes of Yersinia pseudotuberculosis were examined to find out about their cell surface hydrophobicity and virulence plasmid-associated properties. All the strains which aggregated in 0.9% saline expressed the properties of calcium-dependent growth and autoagglutination. However, the hydrophilic strains did not possess virulence plasmid-associated properties. The above results suggest that the salting-out test with 0.9% saline could be an effective measure to differentiate the virulence plasmid-carrying strains of Y. pseudotuberculosis from those of plasmidless virulence.

[Activated macrophages in the peritoneal fluid of women with endometriosis: examination of the intracytoplasmic localization of endogenous peroxidase and interleukin-1]

In order to study the effect of peritoneal macrophages (M phi) on conception in patients with endometriosis, the total numbers of peritoneal M phi and the proportion of the exudate type, defined on the basis of ultracytochemical localization of endogenous peroxidase (PO) activity, were investigated in 21 patients with endometriosis, five with uterine leiomyoma, three with tubal obstruction and three with carcinomatous peritonitis. An immunocytochemical observation of interleukin-1 (IL-1) was also performed in three patients with endometriosis, one with tubal obstruction, and one male patient with cholelithiasis. The total numbers of peritoneal M phi in patients with endometriosis were significantly higher than in uterine leiomyoma (2.11 x 10(7) v.s. 0.68 x 10(7), p less than 0.025). The total numbers of peritoneal M phi in tubal obstruction (0.96 x 10(7)) were not statistically different from those in uterine leiomyoma. The peritoneal M phi were remarkably increased in number in patients with carcinomatous peritonitis. On ultracytochemical observation of endogenous PO activity, the proportion of exudate M phi to whole M phi was significantly larger in endometriosis than that in uterine leiomyoma (13.3% v.s. 3.5%, p less than 0.025). This type of M phi increased even in stage I endometriosis (p less than 0.005). These data suggest that the abdominal cavity in women with endometriosis is in the stimulated conditions which may lead to infertility. A positive reaction to anti-IL-1 antibody on the cell membrane of all M phi examined in each patient suggests that an immunocytochemical study of IL-1 in M phi is not suitable for evaluating the degree of activation of M phi.

Carbamoylation of hemoglobin in uremic patients determined by antibody specific for homocitrulline (carbamoylated epsilon-N-lysine)

Polyclonal antisera to epsilon-amino-carbamoyl-lysine (homocitrulline) on guinea pig carbamoylated low density lipoprotein were used as probes to identify homocitrulline. These antisera detect homocitrulline in the immunogen and on other carbamoylated blood proteins including those from different species. In vivo carbamoylation of intracellular hemoglobin obtained from uremic patients and carbamoyl-proteins, carbamoylated in vitro, located on erythrocyte and lymphocyte cell surface membranes were detected. Solid phase, direct and competitive ELISAs for homocitrulline were used to analyze carbamoylated blood proteins. In uremic patients carbamoylation of protein by endogenous urea-derived cyanate occurs on the epsilon-amino group of lysine residues. Identification of carbamoylated proteins from uremic patients using an immunochemical probe of site specific antibody provides a way to monitor post-translational modification of proteins due to uremia and may give further insight for understanding the pathophysiology of end stage renal disease.

[Comparison of in vitro susceptibilities of Rickettsia prowazekii, R. rickettsii, R. sibirica and R. tsutsugamushi to antimicrobial agents]

The in vitro activities of 16 antimicrobial agents against Rickettsia prowazekii (Breinl strain), R. rickettsii (Bitterroot strain), R. sibirica (ATCC No. VR151) and R. tsutsugamushi (Gilliam, Karp, Kato, Shimokoshi, Kawasaki and Kuroki strains) were determined by the cell culture method. Tetracycline, demethylchlortetracycline, doxycycline, minocycline, chloramphenicol, kitasamycin and rifampicin were generally effective (MIC, 0.005-0.78 micrograms/ml) to all strains tested. Quinolones such as norfloxacin, ciprofloxacin and ofloxacin were moderately active, but they were less active against R. tsutsugamushi than other rickettsial species. Penicillins and cephems showed low activity against most of the strains tested, but high concentrations of benzylpenicillin (MIC, 25-50 micrograms/ml) inhibited R. prowazekii, R. rickettsii and R. sibirica. These findings may be applicable for differentiation of species of genus Rickettsia.

Granulopoietic effects of colony-stimulating factor obtained from urine of patients with aplastic anemia on normal and cyclophosphamide-treated mice

Colony-stimulating factor (CSF) was partially purified from urine of patients with aplastic anemia using DEAE-cellulose and concanavalin A-Sepharose. This partially purified CSF caused significant neutrophilia in the peripheral blood of normal mice by (a) single or continual intraperitoneal injection(s) in vivo, and also revealed a specific activity of 1.4 x 10(3) U/absorbance unit (AU) at 280 nm in vitro, with less than 1 ng/AU endotoxin. In addition, this CSF induced faster recoveries of neutrophils in the peripheral blood and progenitor spleen cells of cyclophosphamide (CY)-treated mice. These findings suggest that the CSF used in this study accelerated the differentiation of the granulocytic cells and the proliferation of granulocyte colony-forming units in the spleen. These effects contributed to a rapid recovery from neutropenia in mice treated with CY.

Uterine papillary serous carcinoma with high levels of serum carcinoembryonic antigen. Response to combination chemotherapy

A case of metastatic uterine papillary carcinoma with elevated serum carcinoembryonic antigen (CEA) is reported. The patient presented with ascites and pleural effusions and with a high level of CEA (258 ng/ml) 3 months after primary surgical resection and postoperative irradiation had been performed. Her complete response, although temporary, to two kinds of combination chemotherapy was evaluated using serial estimations of the serum CEA.

Cytological characterization of NOR in the bivalent of Saccharomyces cerevisiae

We cytologically characterized the nucleolar organizer region (NOR) on the bivalent in the yeast Saccharomyces cerevisiae. We used staining with 4'-6-diamidino-2-phenylindole (DAPI), chromomycin A3, and silver nitrate and in situ hybridization technique and utilized a video-intensified microscope system with an ultra-high-sensitive video camera. The results showed that of 16 bivalents of S. cerevisiae, the longest was a recognizable nucleolar chromosome which has an annular and synaptonemal complexless NOR in its submedian portion. The NOR was comprised of 2.65 X 10(9) D DNA which corresponded to 118 copies per haploid of rDNA repeating units. This evidence is discussed in terms of the possible participation of the annular NOR in suppressing the meiotic recombination of the rDNA gene clusters.

Solubilization and characterization of rat brain alpha 2-adrenergic receptor

alpha 2-Adrenergic receptors labelled by [3H]-clonidine (alpha 2-agonist) can be solubilized from the rat brain in a form sensitive to guanine nucleotides with a zwitterionic detergent, 3-[3-(cholamidopropyl)-dimethylammonio]-1-propane sulfonate (CHAPS). About 40% of the original [3H]CLO binding sites in the membranes were solubilized with 6 mM CHAPS. Separation of the soluble [3H]CLO-bound complex was performed by the vacuum filtration method using polyethylenimine-treated GF/B filters. Solubilized [3H]CLO binding sites retained the same pharmacological characteristics of membrane-bound alpha 2-adrenergic receptors. Scatchard plots of [3H]CLO binding to solubilized alpha 2-receptors were curvilinear, indicating the existence of the two distinct binding components. Solubilized receptors were eluted as a single peak from Bio-Gel A-1.5 m column with a Stokes radius of 6.6 nm. The isoelectric point was 5.6-5.8. Regulations of the receptor binding by guanine nucleotides, monovalent cations, and sulfhydryl-reactive agents were maintained intact in the soluble state, whereas those by divalent cations were lost. The apparent retention of receptors and guanine nucleotide binding regulatory component(s) in the soluble state may allow a investigation of the regulation mechanisms of the brain alpha 2-adrenergic receptor system at the molecular level.

Initial detection of [3H]clonidine binding to solubilized rat brain alpha 2-adrenergic receptors: regulation by guanine nucleotides

Alpha 2-adrenergic receptors labeled by [3H]clonidine (alpha 2-agonist) can be solubilized from the rat brain with a zwitterionic detergent, 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate (CHAPS). CHAPS-solubilized receptors have the same characteristics of membrane-bound alpha 2-receptors in the brain, and the regulation of receptor binding by guanine nucleotides is retained in the soluble state.

[Fundamental study on tissue distribution of ceftriaxone in the field of obstetrics and gynecology]

Fundamental study on tissue distribution of ceftriaxone (Ro 13-9904, CTRX), a new cephalosporin parenteral antibiotic, was studied and the following results were obtained. CTRX had been administered by intravenous drip infusion with 1 g to 9 cases who received simple total hysterectomy. The level of CTRX in the cubital venous serum and uterine arterial serum was determined as well as the tissue concentration in the oviduct, ovary, endometrium, myometrium, cervix uteri and portio vaginalis. The level in the oviduct and portio vaginalis was generally high, although it was observed only in a few cases. The variation of the level in the myometrium was large. CTRX is expected to be clinically useful considering the fact that its half-life time is 8.5 hours, which is longer than that of existing cephalosporin antibiotics.

Isolation of Rickettsia tsutsugamushi antigenically different from Kato, Karp, and Gilliam strains from patients

Rickettsia tsutsugamushi strains from three recent patients of Tsutsugamushi disease in Niigata Prefecture were isolated primarily in mice and then in L cell cultures. By this procedure, low virulent strains to mice, as well as high virulent ones, could be isolated and cultivated serially in L cell cultures, suggesting the usefulness of L cells for isolation of this species of rickettsia. Each newly isolated strain was identified as a member of R. tsutsugamushi from the results of cross immunological tests and morphological observation. On the other hand, it was recognized that one of these rickettsiae showed immunological properties distinguishable from the prototype strains of Kato, Karp, and Gilliam by the cross complement fixation test, and also had low virulence in mice.

Microbial transformation of maridomycin III by Serratia marcescens

Two transformation products of maridomycin (MDM) III, MDM-S1 and MDM-S2 named after Serratia marcescens, were isolated by silica gel chromatography. NMR and IR analysis revealed that MDM-S1 and -S2 had no aldehyde group at C-18 on the macrolactone ring, and that the hydroxyl group at C-9 seemed to disappear. Although MDM-S1 and -S2 are less active against Gram-positive bacteria than starting MDM III they are interesting materials in view of the introduction of nitrogen into each molecule, and that the transformation products are produced by Gram-negative bacteria which are thought to be insensitive to macrolide antibiotics.

M-9337, a new antistreptolysin, produced by Streptomyces sp

A new biologically active substance, M-9337, was obtained from Streptomyces strain M-9337, a soil isolate. The producing organism was subsequently determined to be a new strain and named Streptomyces antihaemolyticus M-9337. The active substance was prepared as white yellow powder from culture broth by solvent extraction and silica gel thin-layer chromatography. It showed no antimicrobial activity and potent inhibitory activity against streptolysin, a type of hemolysin.

Congenital microangiopathic hemolytic anemia: report of a Japanese girl

A 4-year-old Japanese girl had hemolytic anemia, thrombocytopenia, distorted and fragmented red cells in the peripheral blood, and megakaryocytosis in the bone marrow from the newborn period. These features were temporarily relieved and prevented by the infusion of fresh frozen plasma from healthy donors. This would indicate a deficiency in the patient's plasma of factor(s) that inhibit platelet aggregation in the blood vessels. An attempt to demonstrate possible in vitro deficiency of the platelet aggregation-prohibiting factor in the patient's plasma was unsuccessful. Laboratory examinations ruled out red cell fragility, abnormalities of red cell enzymes, abnormal hemoglobins, or immune reaction as underlying mechanisms. Our patient, together with three other patients in the literature with similar clinical features, may constitute a clinical entity that could be called "congenital microangiopathic hemolytic anemia".

[In vitro experiment on combination effect of chromomycin A3 and amphotericin B (author's transl)]

The combination effect of chromomycin A3 and amphotericin B against HeLa cells and Bacillus subtilis ATCC 6633 by the agar plate diffusion and the serial dilution method was examined. As a result, evident synergistic effect was observed when the HeLa cell was used as the test cell.

Percutaneous transhepatic drainage: experience in 100 cases

A two-step procedure for percutaneous transhepatic drainage (PTD) of the biliary tract was attempted on 101 patients with obstructive jaundice, 29 with benign and 71 with malignant lesions, and was successful in 100. With this procedure, marked clinical improvement, with reduction in levels of serum bilirubin, SGOT, SGPT and alkaline phosphatase, was achieved after 1-2 weeks as a preoperative step or for continuous drainage in inoperable cases. In one patient 8 dys after PTD, however, a complicating large intrahepatic hematoma proved fatal. Emergency operation was necessary in three of the four patients who developed bile peritonitis due to dislocation of the catheter and in one with intra-abdominal bleeding. Our results suggest that this procedure is very useful in the diagnosis and management of certain obstructive diseases of the biliary tract.

Tendomycin, a new antitumor antibiotic isolated from Streptomyces No. 9034

A new antibiotic designated tendomycin was isolated from the culture of Streptomyces No. 9034. The antibiotic is active against Gram-positive bacteria, fungi and cultured cancer cells, and shows an inhibitory effect of EHRLICH carcinoma in mice.

Kinetic studies on enzymatic acetylation of chloramphenicol in Streptococcus faecalis

The kinetics of chloramphenicol (CP) acetylation by CP acetyltransferase from Streptococcus faecalis was studied. CP was shown to be acetylated enzymatically to its 3-O-acetyl derivative (3-AcCP) in the presence of acetyl coenzyme A, after which 3-AcCP was converted nonenzymatically to its 1-O-acetyl isomer, 1-O-acetyl CP (1-AcCP). At equilibrium, the 1-AcCP and 3-AcCP were present in a 1:4 ratio. Subsequently the diacetylated product, 1,3-O-O-diacetyl CP [1,3-(Ac)2CP], was enzymatically produced from 1-AcCP by the same enzyme. Theoretical calculation of rate constants (k1, k2, k3) for each successive reaction is as follows: (Formula: see text). This calculation gave k1 = 0.4 min-1, k2 = 0.002 min-1, and k3 = 0.016 min-1. Experimental results agreed closely with these calculated values.

Resistance mechanism of chloramphenicol in Streptococcus haemolyticus, Streptococcus pneumoniae and Streptococcus faecalis

The chloramphenicol resistance of Streptococcus haemolyticus, Streptococcus pneumoniae and Streptococcus faecalis isolated from clinical materials was proved to be due to an inactivating enzyme produced by these bacteria. The inactivated products of chloramphenicol were identified as 1-acetoxy, 3-acetoxy and 1,3-diacetoxy derivatives by thin-layer chromatography and infrared spectroscopy. The responsible enzyme was thus confirmed to be chloramphenicol acetyltransferase. The enzyme was inducible. It was partially purified by ammonium sulfate precipitation, DEAE-cellulose chromatography and gel filtration on Sephadex G-150. The enzymes obtained from S. haemolyticus, S. pneumoniae and S. faecalis have been compared with the conclusion that they are identical with respect to molecular weight (approximately 75,000-80,000), optimum pH and heat stability.