Adenylate cyclase and guanylate cyclase activity in normal and leukemic human lymphocytes

Adenylate cyclase (AC) and guanylate cyclase (GC) activities were studied in normal B-enriched and T-enriched lymphocytes, in lymphocytes of children with acute lymphocytic leukemia (ALL), and in lymphocytes of adults with chronic lymphocytic leukemia (CLL). AC activity was greater in normal B than T lymphocytes (215 pmole/min/mg protein versus 80 pmole in the membrane-enriched fraction) and i both increased greatly after stimulation with isoproterenol and more so with prostaglandins E and F2 alpha. In leukemic lymphocytes, AC showed depressed activity (20 pmole in ALL cells and 55 pmole in CLL cells) and was less sensitive to hormonal stimulation: this loss of sensitivity occurred to a greater extent in ALL than in CLL lymphocytes. GC activity was greater in normal T than B cells (in membrane-enriched fraction: 10.2 pmole versus 5.3 pmole). It increased little with isoproterenol and prostaglandins stimulation, and much more with sodium azide and dehydroascorbic acid stimulation. GC activity was increased in both types of leukemic lymphocytes (23 pmole for ALL cells and 18 pmole for CLL cells) and was insensitive to stimulation. Possible derangement of cyclase and cyclic nucleotide regulation in leukemic cells is suggested.     

A highly sensitive immunoassay for the detection of prion‐infected material in whole human blood without the use of proteinase K

BACKGROUND: The causal association of variant Creutzfeldt‐Jakob disease (vCJD) with bovine spongiform encephalopathy has raised significant concerns for public health. Assays for vCJD infection are vital for the application of therapeutics, for the screening of organ donations, and to maintain a safe blood supply. Currently the best diagnostic tools for vCJD depend upon the detection of disease‐associated prion protein (PrP^Sc), which is distinguished from normal background PrP (PrP^C) by proteinase K (PK) digestion, which can also degrade up to 90% of the target antigen. STUDY DESIGN AND METHODS: A sandwich enzyme‐linked immunosorbent assay method was developed using unique antibodies for the detection of disease‐associated PrP in the absence of PK treatment. In combination with immunoprecipitation the assay was optimized for the detection of pathogenic PrP in large volumes of whole blood. RESULTS: Optimization of the assay allowed detection of 2 × 10⁴ LD₅₀ units/mL spiked in whole blood. Application of the assay to clinically relevant volumes enabled the detection of 750 LD₅₀ units/mL in 8 mL of whole blood. CONCLUSION: By combining the use of a unique antibody that selectively immunoprecipitates PrP^Sc with glycoform‐restrictive antibodies we have developed a rapid assay for vCJD infection that does not require any PK treatment to achieve high levels of specificity in whole human blood, the most challenging potential analyte. The sensitivity of detection of vCJD infection is greater than the equivalent of a more than 2.5 million‐fold dilution of infected brain, providing a highly sensitive immunoassay compatible with blood screening.     

Development of rapid PCR method for simultaneous identification of species, specific capsular type, and toxigenicity of Pasteurella sp. isolates

Toxigenicity, species, and type species of Pasteurella multocida isolates cannot be differentiated by morphology or standard biochemical reactions. A more rapid method is needed for P. multocida detection from clinical cases. These findings provide rapid insights into the characteristics of P. multocida isolates and suggest that this method can identify toxigenic and specific capsular type P. multocida. A PCR assay has been developed for rapid detection of P. multocida and differentiation of capsular types A and D. In this rapid method, kmt1, capA and capD, and toxA genes were amplified and a reliable multiplex PCR method for the detection of P. multocida in sheep and goats in the south of Iran was designed. Twenty isolates were obtained, which evinced characteristic morphological and cultural properties. Ten samples were identified simultaneously through the presence of the kmt1 gene as P. multocida species, the hydD–hydC gene as type A capsule, and the toxA gene as dermonecrotic toxin by mPCR, but none of them belonged to type D.     

Dermoscopic findings of a congenital smooth muscle hamartoma in an infant

Cutaneous smooth muscle hamartoma is an uncommon, benign tumor developing in the dermis as a result of disorganized hyperproliferation of arrector pili muscle fibers. We present a 1-month-old infant with a congenital smooth muscle hamartoma together with the dermoscopic findings of the case. Dermoscopy can be a helpful non-invasive tool in diagnosing congenital smooth muscle hamartoma due to its distinct findings that help to differentiate it from close mimickers like solitary mastocytoma.     

Validation of the PHQ-9 as a screening instrument for depression in diabetes patients in specialized outpatient clinics

Background  

For the treatment of depression in diabetes patients, it is important that depression is recognized at an early stage. A screening method for depression is the patient health questionnaire (PHQ-9). The aim of this study is to validate the 9-item Patient Health Questionnaire (PHQ-9) as a screening instrument for depression in diabetes patients in outpatient clinics.     

Mineral balance and whole body bone mineral content in very low-birth-weight infants

Fat and mineral metabolic balance studies were performed in 25 normal very low-birth-weight infants ( 1500 g at birth) fed either pooled pasteurized human milk supplemented with calcium, phosphorus and magnesium, or a preterm formula. Calcium, phosphorus and magnesium intake were similar in both groups and averaged 100mg/kg/day, 72 mg/kg/day and 8 mg/kg/day, respectively. Calcium and phosphorus retention was higher in the subjects fed fortified human milk than in those receiving a preterm formula (65±14 and 62±9mg/kg/day versus 55±12 and 47±7mg/kg/day respectively). The difference was only significant for phosphorus. Magnesium retention was similar in the two groups and averaged 3 mg/kg/day. Fat intake and absorption was significantly higher in the preterm formula fed group than in the one fed fortified human milk (5.5±0.4 g/kg/day and 88±4% versus 4.2±1 g/kg/day, 79±6% respectively). Assessment of the whole body bone mineral content by dual energy X-ray absorptiometry was performed at 3 and 6 months of age in another group of 25 low-birth-weight infants fed either fortified human milk or a preterm formula. Whole body bone mineral content (BMCt) was low (43.3±30.8 g of hydroxyapatite) at 3 months of age (theoretical term) compared to normal full-term newborns at birth. There was no significant influence of the diet. At 6 months of age, BMCt reached 168.6±36.6g, a value similar to that of full-term newborns, with no significant difference between the two regimen groups. The deficit in the 12 subjects who had a BMCt under 30 g at 3 months of age had been corrected at age 6 months. Premature babies fed a pooled pasteurized human milk enriched with calcium, phosphorus and magnesium favored a better retention of calcium and phosphorus. However, no significant influence of the two diets studied was observed on the gain in BMCt over the first 6 months of life.     

Cell growth in plant cultures: An interpretation of the influence of initial weight in cadmium and copper toxicity tests

An approach is presented for conducting and interpreting results of newly established plant cell culture in toxicity studies. Extended culturing produces uniform suspension and facilitates sampling. Primary (new) cultures are more representative of responses of their plant species but produce nonuniform suspension due to clumping and clumping presents unavoidable sampling difficulties. Evaluations were made of the response of plant cell suspension in primary cultures subjected to metal stress in three differente experiment. Sampling and data interpretation were examined in detail, using mathematical models. Cells were selected from callus cultures of Medicago sativa and green Mandevilla pohliana for experiments using copper and from non-green Mandevilla pohliana for an experiment using cadmium. Distributions of as many as 21 elements in soluble and cell-residue compartments were determined. The interaction of treatment with copper and element distribution was emphasized. Culture status was traced microscopically and growth measured as change in cell fresh weight. The initial weight of each culture replicate could not be held constant due to non-uniform suspension. A mathematical model that described the interactions of the initial weight, exposure time, and metal concentrations was developed to analyze the data. The model revealed stimulation of cell growth when subjected to low concentration of copper and no-growth stimulation with low or moderate concentrations of cadmium. This finding resolves some of the confusion in the literature relative to the effect of low doses of cadmium.     

Perioperative complications with the bone-anchored hearing aid.

OBJECTIVE: To discuss perioperative complications associated with the bone-anchored hearing aid (BAHA) and their management. STUDY DESIGN AND SETTING: A retrospective review of 58 patients who underwent implantation of BAHA for unilateral conductive, mixed, or sensorineural hearing losses was performed at a tertiary referral center. RESULTS: Between September 2003 and June 2005, 58 patients underwent implantation of a BAHA. There were 30 female and 28 male patients, with a mean age of 48 years (range 8-80 years). Complications occurred in 19% (11/58) of patients. Most adverse events were seen early in the series. The most common complication, partial or complete loss of the skin graft, occurred in 10% (6/58) of patients. These were managed successfully with local wound care. Five percent (3/58) of patients had skin growth over the abutment. Two of these cases were managed with office debridement, whereas 1 patient required revision under general anesthesia. There was implant extrusion in 3% (2/58) of patients, and both of these patients later underwent successful reimplantation. All patients had their implant activated 3 months after surgery. There were no perioperative or postoperative deaths. CONCLUSION: Complications related to BAHA implantation are relatively minor and usually involve partial or complete loss of the skin graft. Most complications were successfully managed in the office.