Detection of novel skeletogenesis target genes by comprehensive analysis of a Runx2(-/-) mouse model

Runx2 is an essential factor for skeletogenesis and heterozygous loss causes cleidocranial dysplasia in humans and a corresponding phenotype in the mouse. Homozygous Runx2-deficient mice lack hypertrophic cartilage and bone. We compared the expression profiles of E14.5 wildtype and Runx2(-/-) murine embryonal humeri to identify new transcripts potentially involved in cartilage and bone development. Seventy-one differentially expressed genes were identified by two independent oligonucleotide-microarray hybridizations and quantitative RT-PCR experiments. Gene Ontology analysis demonstrated an enrichment of the differentially regulated genes in annotations to terms such as extracellular, skeletal development, and ossification. In situ hybridization on E15.5 limb sections was performed for all 71 differentially regulated genes. For 54 genes conclusive in situ hybridization results were obtained and all of them showed skeletal expression. Co-expression with Runx2 was demonstrated for 44 genes. While 41 of the 71 differentially expressed genes have a known role in bone and cartilage, we identified 21 known genes that have not yet been implicated in skeletal development and 9 entirely new transcripts. Expression in the developing skeleton was demonstrated for 21 of these genes.

[Stüve-Wiedemann syndrome in two siblings: focusing on a male patient with the longest actual survival rate]

BACKGROUND

We report on two siblings with Stüve-Wiedemann syndrome (SWS). The older patient, a 16-year-old boy, is -- as to our knowledge -- the longest-term survivor of this syndrome worldwide. The younger sister with the same clinical and radiographic findings died at the age of 10 months.

DEFINITION

Characteristic clinical symptoms are: muscular hypotonia, camptodactyly; respiratory insufficiency, swallowing difficulties; reduced sweating with heat intolerance, episodes of hyperthermia. Typical radiographic findings are: progressive bone bowing, unusual bone fractures, abnormal trabecular pattern, middle face hypoplasia.

GENETICS

The SWS is identical with the Schwartz-Jampel syndrome (SJS) type 2, which is gene-located on chromosome 1. So far further genetic details of the SWS can be expected in the near future. The genetic transmission is autosomal recessive. In inbred high risk populations the occurrence of the SWS is increased.

THERAPY

For the present only symptomatic therapy is available: extended intensive care during infancy, supportive pediatric orthopedics later on.

Application of mouse monoclonal antibodies for identification of antigen regions of human thyroid peroxidase in adolescents with Graves' disease and non-toxic multinodular goiter by flow cytometry

Thyroid peroxidase (TPO) is the major thyroid autoantigen recognized by serum autoantibodies from patients with Graves' disease (GD) or Hashimoto's thyroiditis directed to two immunodominant conformational regions termed A and B. The epitopes of human TPO have been defined using a panel of mouse monoclonal antibodies (mAbs). The aim of this study was to estimate the expression of chosen surface antigen regions of TPO (1, 18, 30, 64 epitopes) on thyroid cells in 15 patients with non-toxic multinodular goiter (NTMG) and 15 patients with GD. The thyrocytes were identified by indirect method: in the first stage we added mouse monoclonal autoantibodies specific for TPO regions and in the second stage we conjugated this complex with rabbit anti-mouse antibodies IgG (Fab')(2) with FITC. All investigations were performed by flow cytometry using Coulter EPICS XL apparatus. The percentages of thyrocytes with expression of epitopes 1, 18, 30, 64 TPO were measured in relation to the respective anti-TPO concentrations: 50-1600 microg/ml. The analysis of epitopes located in immunodominant regions (IDR) of TPO revealed higher percentages of thyrocytes in cases with GD in comparison to NTNG. The most predominant difference was observed for mAb 64 epitope (48 vs 7%, p < 0.019; 39 vs 5%, p < 0.017) at the concentration of 100-200 microg/ml mAbs. The expression of 18 epitope on thyrocytes was also statistically higher in Graves' patients than in the NTMG (14 vs 6%, p < 0.025) at concentration of 400 microg/ml mAbs. However, this expression was much less pronounced. In all the cases, the percentages of thyrocytes with epitopes 1 and 30 were in low detection (8-15% of positive cells). In conclusion, our findings suggest that the elevated expression of TPO epitopes 18 and 64 in young patients with thyroid autoimmune diseases increase stimulation and activation of thyroid cells during inflammatory reaction within the thyroid gland. In addition, predominant expression of 64 TPO epitope that recognizes B domain in GD patients could be a useful marker of the immune process in the thyroid gland.

Influence of esterification and modification of A-ring in a group of lupane acids on their cytotoxicity

The aim of this work was to find an optimal ester group for preparation of lupane derivatives connecting high cytotoxicity with good chemical and pharmacological properties. Activities of methyl-, pivaloyloxymethyl- (Pom-), and acetoxymethyl- (Acm-) esters were compared with the activity of free acids. Although the methyl- and Pom-esters were generally less active than free acids, some Acm-esters had cytotoxicity similar to or even better than the starting compounds. Cytotoxic activity was measured in five cancer cell lines.

Correlation of cytotoxic activity of betulinines and their hydroxy analogues

This research is based on intention to prepare and test 3beta-hydroxy and 3beta,28-dihydroxy analogues of new pro-apoptotic derivatives (betulinines) using selective hydrolysis procedure and strategic protective groups. The evaluation of cytotoxicity of prepared compounds on several tumor cell lines using an MTT test was our interest. It was found that hydrolysis of acetates in betulinines afforded compounds with higher cytotoxicity in case of 18-lupene-21-ones (e.g., ethyl 3beta-hydroxy-21-oxolup-18-en-28-oate), whereas hydrolysis of the 18-lupene-21,22-diones gave less active derivatives.

Efficacy of the fully human monoclonal antibody MOR102 (#5) against intercellular adhesion molecule 1 in the psoriasis-severe combined immunodeficient mouse model

BACKGROUND

Psoriasis is considered as a chronic immune-mediated disease characterized by inflammation and proliferation of the epidermis.

OBJECTIVES

Targeting intercellular adhesion molecule 1 (ICAM-1) is an attractive therapeutic option as this molecule is critically involved in leucocyte adhesion and extravasation as well as in lymphocyte activation.

METHODS

We have selected the fully human monoclonal antibody MOR102 (#5) against ICAM-1 from the Human Combinatorial Antibody Library (HuCAL). This antibody, as human IgG4 [corrected] was tested for its ability to interfere with lymphocyte activation and adhesion in vitro as well as for its antipsoriatic efficacy in vivo using the psoriasis-severe combined immunodeficient (SCID) mouse model.

RESULTS

The antibody demonstrated efficient inhibition of lymphocyte adhesion to ICAM-1 in vitro, with an IC(50) of approximately 0.4 microg mL(-1) (3 nmol L(-1)). In addition, MOR102 (#5) reduced lymphocyte proliferation in mixed lymphocyte cultures by approximately 50%. The in vivo efficacy of MOR102 (#5) was tested on grafts derived from lesional skin of patients with chronic plaque-stage psoriasis transplanted on to SCID mice. Intraperitoneal injection of 10 mg kg(-1) of MOR102 (#5) antibody every alternate day over a period of 4 weeks resulted in reconstitution of orthokeratotic differentiation and a significant (P < 0.05) reduction in epidermal thickness as well as marked reduction in the inflammatory infiltrate. Therapeutic activity may be related to the targeting of ICAM-1 on keratinocytes and thus preventing efficient activation of local T cells.

CONCLUSIONS

Based on the efficacy of the fully human monoclonal antibody MOR102 (#5) shown in vitro as well as in vivo in the psoriasis-SCID mouse model, initiation of clinical studies is indicated.

Intrinsic constraint of unlinked total elbow replacements--the ulnotrochlear joint

BACKGROUND

Many unlinked total elbow replacement designs with radically differing articular geometries exist, suggesting that there is no consensus regarding an optimal design. A feature inherent to the articular design is the intrinsic constraint afforded to the joint by the implant. Our aim was to compare the intrinsic constraints of unlinked implants with that of the normal ulnotrochlear joint.

METHODS

We tested twelve cadaveric ulnotrochlear joints with a custom-made multiple-axis materials testing machine. With compressive loads ranging from 10 to 100 N, the joints were moved in either valgus or varus directions at 90 degrees of flexion. The ulnotrochlear components from a single example of five medium-sized unlinked elbow replacements (Ewald, Kudo, Pritchard ERS, Sorbie-Questor, and Souter-Strathclyde) were also tested. The recorded measurements included the torques and forces, angular displacement, and axial displacement of the humerus relative to the ulna.

RESULTS

In general, the peak torque and the constraint ratio significantly increased with increasing compressive load for the implants as well as for the normal elbow. In valgus displacement, the Souter-Strathclyde implant had the highest and the Sorbie-Questor had the smallest peak torque and the Souter-Strathclyde had the highest and the Ewald had the smallest constraint ratio. In varus displacement, the Kudo had the highest and the Ewald had the smallest peak torque and constraint ratio.

CONCLUSIONS

The constraint ratio is a characteristic that is useful for describing elbow joint behavior and for comparing the behavior of implants with that of the human elbow. Of the unlinked implants tested, the Souter-Strathclyde and Kudo prostheses most closely approximated the behavior of the human elbow joint. Implants that resemble the human elbow in appearance do not replicate normal behavior consistently, whereas other implants that do not resemble the human elbow closely do not deviate markedly from human behavior. Thus, much basic information about elbow form and function is needed to improve the performance of total elbow prostheses.

Improving the safety of laparoscopic cholecystectomy: the routine use of preoperative magnetic resonance cholangiography

BACKGROUND

The aim of this study was to determine the value of routinely performed preoperative magnetic resonance cholangiography (MRC) in detecting common bile duct (CBD) stones in patients stated to undergo elective laparoscopic cholecystectomy. In addition, we used MRC to investigate possible variants of the cystic duct.

METHODS

Magnetic resonance cholangiography was performed preoperatively in 773 patients (311 male and 462 female; median age 55 years, range 16-91) who had no clinical signs of cholestasis prior to undergoing elective laparoscopic cholecystectomy. In cases where the MRC was positive for CBD stones, endoscopic retrograde cholangiopancreatiography (ERCP) was then performed. A total of 532 patients were available for continuous postoperatively follow-up (median 54 months, range 36-85). In 462 patients (247 female, and 215 male), MR images were also reviewed for variants of the cystic duct.

RESULTS

In 705 patients (91%), MRC was negative for CBD stones. In 64 patients (9%) MRC was positive. Of these patients, 47 (6%) had CBD stones on ERCP. In 12 patients (2%), MRC was false positive. In five cases (0.6%), ERCP had an inconclusive result postoperative follow-up (532 patients, or 69%) revealed evidence of CBD stones in three patients (10.4%) despite a preoperative negative MRC result. Anatomical variants in the course of the cystic duct and its confluence with the common bile duct were found in 27 of 462 patients (6%).

CONCLUSIONS

Magnetic resonance cholangiography proved to be a reliable screening technique in the preoperative evaluation of patients with silent CBD stones. Imaging of the course of the cystic duct is possible in a high percentage of cases. Therefore, MRC can be recommended as a screening technique before laparoscopic cholecystectomy.

Tobacco attributable deaths in South Africa

BACKGROUND

In mid 1998, a question "Was the deceased a smoker five years ago?" was introduced on the newly revised South African death notification form.

DESIGN

A total of 16,230 new death notification forms from 1998 have been coded, and comparison of the prevalence of smoking among those who died of different causes was used to estimate, by case-control comparisons, tobacco attributed mortality in South Africa. Cases comprised deaths from causes known (from other studies) to be causally associated with smoking, and controls comprised deaths from medical conditions expected to be unrelated to smoking. Those who died from external causes, and from diseases strongly related to alcohol consumption, were excluded.

SUBJECTS

Reports were available from 5340 deceased adults (age 25+), whose smoking status was given by a family member.

RESULTS

Significantly increased risks were found for deaths from tuberculosis (odds ratio (OR) 1.61, 95% confidence interval (CI) 1.23 to 2.11), chronic obstructive pulmonary disease (COPD) (OR 2.5, 95% CI 1.9 to 3.4), lung cancer (OR 4.8, 95% CI 2.9 to 8.0), other upper aerodigestive cancer (OR 3.0, 95% CI 1.9 to 4.9) and ischaemic heart disease (OR 1.7, 95% CI 1.2 to 2.3).

CONCLUSION

If smokers had the same death rate as non-smokers, 58% of lung cancer deaths, 37% of COPD deaths, 20% of tuberculosis deaths, and 23% of vascular deaths would have been avoided. About 8% of all adult deaths in South Africa (more than 20 000 deaths a year) were caused by smoking.

The role of the therapeutic team in shaping eating habits and lifestyle in children with dietary calcium deficiency

PURPOSE

Assessment of the effect of low-calcium diet on bone mineral content in children and adolescents.

MATERIAL AND METHODS

The study involved 89 children (49 girls and 40 boys) aged 5-18 years, in whom diseases affecting bony metabolism had been excluded. Children with a history of dietary calcium content below 500 mg/day were recruited. The study group was divided according to age: group I, age 5-9 years (children before puberty); group II, age 9-15 years (early puberty); group III, 15-18 years (late puberty). Dual energy X-ray absorptiometry (DEXA) was used for densitometric measurements. Bone mineral density (BMD) was assessed in the whole skeleton (total BMD), in vertebrae L2-L4 (spine BMD) in g/cm2 and as Z-score. Concentrations of Ca, Ca2, P, activity of alkaline phosphatase (AP) and its bony isoenzyme were determined in the serum.

RESULTS

Total bone mass below 5th percentile (according to the norm for age and gender) was found in 56.98% of the children involved in the study. A significant reduction was noted in the spine mineral mass in boys (p < 0.01) as compared to girls (0.731 +/- 0.17 g/cm2 and 0.835 +/- 0.19 g/cm2, respectively). The lowest mean Z-score (-1.850) was observed in group III as compared to group I (-1.194) (p < 0.01) and group II (-1.201) (p < 0.05). There were statistically significantly positive correlations between total and spine BMD and BMI. The correlation coefficient was r = 0.56 and r = 0.41 (p < 0.001), respectively.

CONCLUSIONS

In the majority of the children (c. 60%), a reduction in bone mineral content was found. The lowest Z-score (-1.850) was revealed in the oldest children, which may disturb the process of reaching the optimum level of the peak bone mass.

[Infrared pupilometry measured by digital photography]

BACKGROUND

Pupil size is mainly controlled by the action of parasympathetic and sympathetic nerves. Measurement of pupil size and reaction to light are important in both experimental and clinical settings.

METHODS AND RESULTS

We have established infrared pupilometry using a commercially available digital camera and a calculation with standard computer software. Volunteers were habituated in a dark room for five minutes before pupil evaluation. Pupil measurement was repeated three times and the diameter was calculated according to the following formula: D(mm)=30/S(pix)*D(pix), where D(pix) and D(mm) represent the pupil size in pixels and millimetres, respectively, and S(pix) was the length in pixels of a 30 mm standard. Our method was validated by the measurement of the diameter of calibration circles printed on a white sheet of paper. Deviation from the actual size was less than 3%. We also compared the results of pupil size obtained by our method, with the results of the pupilometer Pupillscan II measurement. The relative difference between the two methods was always less than 5%. The applicability of the method was illustrated by measurement of the pharmacodynamic effect of the single dose of tramadol (100 mg p.o.) in seven volunteers, compared with control placebo-treated volunteers.

CONCLUSIONS

The proposed method is precise and sensitive enough to be used for pupil size determination.

Synthesis of A-seco derivatives of betulinic acid with cytotoxic activity

In this study, the relationships between the chemical structure and cytotoxic activity of betulinic acid (1) derivatives were investigated. Eight lupane derivatives (1-8), one of them new (6), five diosphenols (9-13), four of them new (10-13), two new norderivatives (14 and 15), five seco derivatives (16-20), four of them new (16, 17, 19, and 20), and three new seco-anhydrides (21-23) were synthesized from 1, and their activities were compared with the activities of known compounds. The effects of substitution on the A-ring and esterification of the carboxyl group in position 28 on cytotoxicity were of special interest. Significant cytotoxic activity against the T-lymphoblastic leukemia cell line CEM was found in diosphenols 9 and 13 (TCS(50) 4 and 5 micromol/L) and seco-anhydrides 22 and 23 (TCS(50) 7 and 6 micromol/L). All compounds were also tested on cancer cell lines HT 29, K562, K562 Tax, and PC-3, and these confirmed activity of diosphenols 9, 10, and 11 and anhydride 22. Diosphenols, as the most promising group of derivatives, were further tested on four more lines (A 549, DU 145, MCF 7, SK-Mel2).

Acceptability and utilisation of voluntary HIV testing and nevirapine to reduce mother-to-child transmission of HIV-1 integrated into routine clinical care

OBJECTIVES

Use of nevirapine for prevention of mother-to-child transmission (PMTCT) of HIV-1 has been routine clinical care at Coronation Women and Children's Hospital since April 2000. We assessed the effect of regular audit and targeted interventions on the utilisation of the PMTCT programme.

METHODS

Review of antenatal cards and hospital records of women discharged following delivery, in three time periods between October 2000 and February 2002. Following the initial audit an intervention was implemented to eliminate weaknesses in our PMTCT service. Following the second audit the hospital became a pilot site for the Gauteng PMTCT programme.

RESULTS

In the initial audit 53.2% of women (159/299) were tested for HIV and received their results, while 56% (14/25) of identified HIV-infected women, and 16% (4/25) of their infants, received nevirapine. By the third audit 74.3% of women (266/358) received their results, and 86% (43/50) of HIV-positive women and 74% (37/50) of newborns were documented to have received nevirapine. In all three audits over 90% of women initiating antenatal care at the hospital were tested for HIV, while women who initiated care at district community clinics were less likely to receive testing.

CONCLUSIONS

Ongoing audit has been important for targeting obstacles to detection of HIV-infected women and documented nevirapine uptake by women and infants. Rates of HIV testing and nevirapine use have increased significantly. Voluntary counselling and testing for HIV and use of nevirapine are acceptable to pregnant women in our setting. Roll-out of the pilot programme to district community clinics is essential for further improvement.

Short- and long-term reproducibility of autonomic measures in supine and standing positions

Autonomic nervous tests and heart rate variability (HRV) have been used to assess cardiac autonomic function and to evaluate long-term prognosis. The aim of this study was to evaluate the short- and long-term reproducibility of HRV parameters and autonomic nervous tests according to body position (supine or standing). The study group consisted of 26 healthy subjects. Autonomic nervous tests and HRV were performed twice during the day and the results were averaged. The protocol was then repeated 3 days after each examination and also after 6 and 24 months. Autonomic nervous tests included deep breathing, Valsalva manoeuvre and isometric muscle exercise (handgrip), as well as blood pressure and heart rate in response to standing. ECG recordings were taken for 10 min during spontaneous breathing for HRV analysis. We found that the reproducibility of some parameters of the autonomic nervous test were independent of body position [E/I ratio (heart rate response to deep breathing)], whereas other parameters were dependent on body position (Valsalva manoeuvre and blood pressure response to sustained handgrip). In addition, within-day measurements of those parameters varied from non-reproducible (Valsalva ratio, handgrip and blood pressure response to standing) to moderately reproducible [E/I ratio and 30/15 ratio (heart rate response to standing)]. Among the HRV parameters, we found that total power (TP), low (LF)- and high (HF)-frequency were reproducible not only for measurements made within the same day, but also during short- and long-term observations, and only the LF/HF ratio was dependent on body position. We conclude that only a few autonomic nervous tests are reproducible in the short- and long-term. Because HRV parameters obtained during spontaneous respiration showed high reproducibility for measurements made within the same day as well as in the short- and long-term, they should be used instead of autonomic nervous tests when long-term observations are carried out in a healthy population.

[Controversies in the diagnosis of growth hormone deficiency]

Evaluation of the GH secretion using pharmacological GH stimulation tests remains controversial in the diagnosis. The authors present diagnostic problems in recognizing growth hormone deficiency on the basis of literature.