Genetic loci regulate Sarbecovirus pathogenesis: A comparison across mice and humans

Coronavirus (CoV) cause considerable morbidity and mortality in humans and other mammals, as evidenced by the emergence of Severe Acute Respiratory CoV (SARS-CoV) in 2003, Middle East Respiratory CoV (MERS-CoV) in 2012, and SARS-CoV-2 in 2019. Although poorly characterized, natural genetic variation in human and other mammals modulate virus pathogenesis, as reflected by the spectrum of clinical outcomes ranging from asymptomatic infections to lethal disease. Using multiple human epidemic and zoonotic Sarbecoviruses, coupled with murine Collaborative Cross genetic reference populations, we identify several dozen quantitative trait loci that regulate SARS-like group-2B CoV pathogenesis and replication. Under a Chr4 QTL, we deleted a candidate interferon stimulated gene, Trim14 which resulted in enhanced SARS-CoV titers and clinical disease, suggesting an antiviral role during infection. Importantly, about 60 % of the murine QTL encode susceptibility genes identified as priority candidates from human genome-wide association studies (GWAS) studies after SARS-CoV-2 infection, suggesting that similar selective forces have targeted analogous genes and pathways to regulate Sarbecovirus disease across diverse mammalian hosts. These studies provide an experimental platform in rodents to investigate the molecular-genetic mechanisms by which potential cross mammalian susceptibility loci and genes regulate type-specific and cross-SARS-like group 2B CoV replication, immunity, and pathogenesis in rodent models. Our study also provides a paradigm for identifying susceptibility loci for other highly heterogeneous and virulent viruses that sporadically emerge from zoonotic reservoirs to plague human and animal populations.

Common Mechanism of SARS-CoV and SARS-CoV-2 Pathogenesis across Species

Sarbecovirus (CoV) infections, including Severe Acute Respiratory CoV (SARS-CoV) and SARS-CoV-2, are considerable human threats. Human GWAS studies have recently identified loci associated with variation in SARS-CoV-2 susceptibility. However, genetically tractable models that reproduce human CoV disease outcomes are needed to mechanistically evaluate genetic determinants of CoV susceptibility. We used the Collaborative Cross (CC) and human GWAS datasets to elucidate host susceptibility loci that regulate CoV infections and to identify host quantitative trait loci that modulate severe CoV and pan-CoV disease outcomes including a major disease regulating loci including CCR9. CCR9 ablation resulted in enhanced titer, weight loss, respiratory dysfunction, mortality, and inflammation, providing mechanistic support in mitigating protection from severe SARS-CoV-2 pathogenesis across species. This study represents a comprehensive analysis of susceptibility loci for an entire genus of human pathogens conducted, identifies a large collection of susceptibility loci and candidate genes that regulate multiple aspects type-specific and cross-CoV pathogenesis, and also validates the paradigm of using the CC platform to identify common cross-species susceptibility loci and genes for newly emerging and pre-epidemic viruses.

Genetic regulation of immune homeostatic lung leukocyte populations influences respiratory virus induced disease in collaborative cross mice

Immune homeostasis is the state that the immune system maintains in the absence of insult. Perturbation of immune homeostasis can impact autoimmunity/allergy and adversely affect infectious responses. To date, much of the analysis of immune homeostasis has focused on systemic immunity, but it is also likely to be important in an organ specific manner. Since the lungs are a major site of environmental exposure and infection, we used the Collaborative Cross (CC) mouse genetic reference population to study the genetic regulation of the breadth of baseline immune cell populations in the lung and identify loci regulating these cells at homeostasis. We found that all 54 immune cell phenotypes measured showed strong genetic variation in cell type abundances. We identified 28 quantitative trait loci associated with variation in 24 immune cell populations or the relationship between cell populations. Further, we identified significant associations between 20 of these loci and responses to either influenza A virus (IAV) or Severe acute respiratory syndrome associated coronavirus (SARS-CoV) disease in the same strains of mice. Notably, a locus mapped for variation in Ly6C+ monocyte abundance was associated with SARS-CoV weight loss, as well as titer at days 2 and 4 post-infection. This locus is also associated with influenza-induced disease, as measured by weight loss post-infection. Our analysis highlights the strong genetic control of immune homeostasis, and the key role that immune homeostasis plays in contributing to downstream infectious responses. In particular, our analysis suggests that the abundance of a variety of lung leukocyte populations prior to infection could serve as predictors of immune responses to respiratory viruses.

Itch relief in patients with psoriasis: effectiveness of calcipotriol plus betamethasone dipropionate foam

BACKGROUND

Itch is common in psoriasis, adversely affecting health-related quality of life (HRQoL) and sleep.

OBJECTIVE

We evaluated the efficacy of topical fixed-dose combination calcipotriol 50 μg/g plus betamethasone dipropionate 0.5 mg/g cutaneous foam (Cal/BD foam) on itch, itch-related sleep loss and HRQoL vs. foam vehicle.

METHODS

We pooled data from three Phase II/III trials (NCT01536886/NCT01866163/NCT02132936) of Cal/BD foam vs. foam vehicle in adults with mild-severe psoriasis. For itch-related analyses, patients with baseline itch visual analogue scale (VAS) >40 (range 0-100) were analysed. Outcomes included the following: itch VAS reduction >40, ≥70% improvement in itch (Itch70) or itch-related sleep loss, 75% improvement in modified Psoriasis Area and Severity Index (excluding head; mPASI75) and Dermatology Life Quality Index (DLQI) scores 0/1 through 4 weeks.

RESULTS

Of 837 patients, 800 had baseline itch VAS >0 (Cal/BD foam, n = 610; foam vehicle, n = 190); 484 had baseline itch VAS >40. There was no correlation between itch VAS score and mPASI at baseline (R²  = 0.021). In patients with baseline itch VAS >40, more patients achieved itch VAS reduction >40 in the active vs. vehicle group from Day 5 onwards (Day 5: 57.5% vs. 40.2% [P < 0.05]; Week 4: 83.0% vs. 45.8% [P < 0.001]). More Cal/BD-foam-treated patients achieved Itch70 at Day 3 (34.2% vs. 22.5%; P < 0.05) through to Week 4 (79.3% vs. 38.1%; P < 0.001). In patients with baseline itch VAS >40 and sleep loss >20, improvements in itch-related sleep loss occurred at Week 1 and continued through 4 weeks. Itch-related improvements occurred before improvements in mPASI75. There were significant differences in the proportion of Cal/BD-foam- vs. foam-vehicle-treated patients with baseline DLQI >10 (n = 172 vs. n = 50) achieving DLQI ≤1 (25.0% vs. 4.0%; P = 0.001) and DLQI 0 (17.4% vs. 2.0%; P = 0.006) at Week 4.

CONCLUSION

Compared with foam vehicle, Cal/BD foam offers more rapid and effective itch relief, with associated significant improvements in sleep and DLQI.

Increasing the translation of mouse models of MERS coronavirus pathogenesis through kinetic hematological analysis

Newly emerging viral pathogens pose a constant and unpredictable threat to human and animal health. Coronaviruses (CoVs) have a penchant for sudden emergence, as evidenced by severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome CoV (MERS-CoV) and most recently, swine acute diarrhea syndrome coronavirus (SADS-CoV). Small animal models of emerging viral pathogenesis are crucial to better understand the virus and host factors driving disease progression. However, rodent models are often criticized for their limited translatability to humans. The complete blood count is the most ordered clinical test in the United States serving as the cornerstone of clinical medicine and differential diagnosis. We recently generated a mouse model for MERS-CoV pathogenesis through the humanization of the orthologous entry receptor dipeptidyl peptidase 4 (DPP4). To increase the translatability of this model, we validated and established the use of an automated veterinary hematology analyzer (VetScan HM5) at biosafety level 3 for analysis of peripheral blood. MERS-CoV lung titer peaked 2 days post infection concurrent with lymphopenia and neutrophilia in peripheral blood, two phenomena also observed in MERS-CoV infection of humans. The fluctuations in leukocyte populations measured by Vetscan HM5 were corroborated by standard flow cytometry, thus confirming the utility of this approach. Comparing a sublethal and lethal dose of MERS-CoV in mice, analysis of daily blood draws demonstrates a dose dependent modulation of leukocytes. Major leukocyte populations were modulated before weight loss was observed. Importantly, neutrophil counts on 1dpi were predictive of disease severity with a lethal dose of MERS-CoV highlighting the predictive value of hematology in this model. Taken together, the inclusion of hematological measures in mouse models of emerging viral pathogenesis increases their translatability and should elevate the preclinical evaluation of MERS-CoV therapeutics and vaccines to better mirror the complexity of the human condition.

Rapid onset of action of calcipotriol/betamethasone dipropionate cutaneous foam in psoriasis, even in patients with more severe disease

BACKGROUND

The effectiveness of topical therapies in psoriasis is dependent on, amongst other factors, patient adherence. Together with treatment effectiveness and reduction of symptoms, speed of onset and health-related quality of life (HRQoL) are important influencers of adherence.

METHODS

This pooled analysis of three Phase II/III trials evaluated the efficacy of topical fixed-dose combination calcipotriol 50 μg/g plus betamethasone dipropionate 0.5 mg/g cutaneous foam (Cal/BD foam) vs. foam vehicle at early timepoints in mild-to-severe psoriasis using clinically meaningful modified Psoriasis Area and Severity Index (mPASI) and Dermatology Life Quality Index (DLQI) targets.

RESULTS

A greater proportion of Cal/BD-foam- vs. foam-vehicle-treated patients achieved absolute mPASI targets 0 (15.1% vs. 1.0%), ≤1 (41.4% vs. 5.2%), ≤3 (78.5% vs. 29.2%) and ≤5 (90.2% vs. 62.5%) at week 4 (P < 0.001; all targets). Significant differences between Cal/BD-foam- vs. foam-vehicle-treated patients were observed as early as week 1 in those achieving mPASI ≤1 (6.8% vs. 1.5%; P < 0.01), ≤3 (40.4% vs. 22.8%; P < 0.001) and ≤5 (69.7% vs. 50.8%; P < 0.001). In patients with more severe psoriasis (baseline mPASI >10), a greater proportion of Cal/BD-foam- vs. foam-vehicle-treated patients achieved mPASI ≤1 (20.2% vs. 5.9%; P < 0.05), ≤3 (49.2% vs. 8.8%; P < 0.001) and ≤5 (63.7% vs. 26.5%; P < 0.001) at week 4. In patients with severely impaired HRQoL (baseline DLQI >10), a greater proportion of Cal/BD-foam- vs. foam-vehicle-treated patients achieved target DLQI ≤1 or 0 (week 4: DLQI ≤1, 25.0% vs. 4%; P = 0.001; DLQI 0, 17.4% vs. 2.0%; P = 0.006).

CONCLUSION

We report rapid onset of action and greater efficacy with Cal/BD foam vs. foam vehicle, even in patients with more severe psoriasis, manageable with topical treatments. This may support physician management of patient expectations and improve patient adherence, translating into overall topical treatment effectiveness.

The effect of increased classroom ventilation rate indicated by reduced CO2 concentration on the performance of schoolwork by children

The article reports on an experiment which investigated the effect of increased classroom ventilation rate on the performance of children aged 10-12 years. The experiment was executed at two different schools (two classrooms at each school) as a double-blind 2 × 2 crossover intervention where four different performance tests were used as surrogates for short-term concentration and logical thinking. Only complete pairs of test responses were included in the within-subject comparisons of performance, and data were not corrected for learning and fatigue effects. Analysis of the total sample suggested the number of correct answers was improved significantly in four of four performance test, addition (6.3%), number comparison (4.8%), grammatical reasoning (3.2%), and reading and comprehension (7.4%), when the outdoor air supply rate was increased from an average of 1.7 (1.4-2.0) to 6.6 l/s per person. The increased outdoor air supply rate did not have any significant effect on the number of errors in any of the performance tests. Results from questionnaires regarding pupil perception of the indoor environment, reported Sick Building Syndrome symptoms, and motivation suggested that the study classroom air was perceived more still and pupil were experiencing less pain in the eyes in the recirculation condition compared to the fresh air condition.

Malignant Sertoli cell tumour in a young Simmenthal bull--clinical and pathological observations

Tumours are rare in the bovine testicle. A case of malignant Sertoli cell tumour in a 29-month-old Simmenthal bull that was hospitalized with a history of severe unilateral scrotal swelling is reported. On inspection and palpation, the scrotal sac was found enlarged with fluctuant content in the right side. The right testicle was enlarged, hard and indolent. Also the right plexus pampiniformis and funiculus spermaticus were enlarged. Sonograms revealed severe changes in the right testicle with a loss of homogeneity and multiple hyperechogenic areas. After slaughter, the scrotum with testicles were removed and evaluated pathologically. On section, the right testicle contained areas of necrosis, haemorrhage, and mineralization. Histology showed Sertoli cells in tubular structures surrounded by dense fibrous stroma replacing normal testicular tissue. Both lymphatic and blood vessels were infiltrated by neoplastic cells. Immunohistochemically, the neoplastic cells stained positive for vimentin and negative for cytokeratin and S-100. Based on the pathological observations a diagnosis of right-sided malignant Sertoli cell tumour with vascular invasion and hydrocele was established.

Functional gene analysis of individual response to challenge of SIVmac239 in M. mulatta PBMC culture

It has previously been shown in macaques that individual animals exhibit varying responses to challenge with the same strain of SIV. We attempted to elucidate these differences using functional genomics and correlate them to biological response. Unfractionated PBMC from three rhesus macaques were isolated, activated, and infected with SIVmac239. Interestingly, one of the three animals used for these experiments exhibited a completely unique response to infection relative to the other two. After repeated attempts to infect the PBMC from this animal, little or no infectivity was seen across the time points considered, and corresponding to this apparent lack of infection, few genes were seen to be differentially expressed when compared to mock-infected cells. For the remaining two animals, gene expression analysis showed that while they exhibited responses for the same groups of pathways, these responses included differences specific to the individual animal at the gene level. In instances where the patterns of differential gene expression differed between these animals, the genes being differentially expressed were associated with the same categories of biological process, mainly immune response and cell signaling. At the pathway level, these animals again exhibited similar responses that could be predicted based on the experimental conditions. Even in these expected results, the degree of response and the specific genes being regulated differed greatly from animal to animal. The differences in gene expression on an individual level have the potential to be used as markers in identification of animals suitable for lentiviral infection experiments. Our results highlight the importance of individual variation in response to viral challenge.

Enhanced antiviral effect in cell culture of type 1 interferon and ribozymes targeting HCV RNA

We have recently shown that the replication of an HCV-poliovirus (PV) chimera that is dependent upon the hepatitis C virus (HCV) 5' untranslated region (UTR) can be inhibited by treatment with ribozymes targeting HCV RNA. To determine the antiviral effects of anti-HCV ribozyme treatment in combination with type 1 interferon (IFN), we analysed the replication of this HCV-PV chimera in HeLa cells treated with anti-HCV ribozyme and/or IFN-alpha2a, IFN-alpha2b, or consensus IFN. The anti-HCV ribozyme, or any of the IFNs alone have significant inhibitory effects on HCV-PV replication compared to control treatment (> or = 85%, P < 0.01). The maximal inhibition due to IFN treatment (94%, P < 0.01) was achieved with > or = 50 U/ml for either IFN-alpha2a or IFN-alpha2b compared to control treatment. A similar level of inhibition in viral replication could be achieved with a 5-fold lower dose of IFN if ribozyme targeting the HCV 5' UTR was given in combination. For consensus IFN, the dose could be reduced by > 12.5-fold if ribozyme targeting the HCV 5' UTR was given in combination. Conversely, the dose of ribozyme could be reduced 3-fold if given in combination with any of the IFN preparations. Moreover, treatment with low doses (1-25 U/mL) of IFN-alpha2a, IFN-alpha2b, or consensus IFN in combination with anti-HCV ribozyme resulted in > 98% inhibition of HCV-PV replication compared to control treatment (P < 0.01). These results demonstrate that IFN and ribozyme each have a beneficial antiviral effect that is augmented when given in combination.

New results in the theory of Fowler-Nordheim plots and the modelling of hemi-ellipsoidal emitters

This paper reports further progress in understanding the theory of emission-area extraction from Fowler-Nordheim plots, and reports some useful interim results derived by modelling field electron emission from hemi-ellipsoidal emitters. The mathematical nature of the relationship between a new approach to emission-area extraction, recently proposed, and older approaches is demonstrated. The new approach is extended to cover field dependence in emission area. Preliminary results are reported from an investigation into the effects of making erroneous assumptions about the tunnelling barrier seen by the electron and the absence of field dependence in emission area. If wrong theoretical assumptions are made, then emission area can be overpredicted by a factor of as much as 10 or 20. On the other hand, if correct theoretical assumptions are made, then the extracted emission area is close to an emission area derived directly from the model calculations. The problematical nature of the concept of emission area, when emission area is a function of field, is pointed out.

Randomised clinical trials in the Scandinavian Journal of Rheumatology

OBJECTIVE

To identify all reports of randomised clinical trials in the Journal and compare our findings with reports available in Medline.

METHODS

We handsearched the Scandinavian Journal of Rheumatology with supplements for the years 1955-1997 to identify reports of randomised clinical trials and controlled clinical trials.

RESULTS

We identified 445 trial reports. In Medline, 134 of these trials (30%) were indexed as randomised or controlled trials; an additional 50 trials (11%) were available in Medline but were indexed differently. Thus, 261 of the trials (59%) we identified were not indexed in Medline; most of these trials were published in supplements to the Journal.

CONCLUSION

Handsearching of medical journals for randomised trials can be a worthwhile effort. Clinicians and patients will become better informed about the value of different treatment options and researchers will reduce their risk of performing trials that are unnecessary.

Antitumor and antimetastatic activity of ribozymes targeting the messenger RNA of vascular endothelial growth factor receptors

Chemically stabilized hammerhead ribozymes are nuclease-resistant, RNA-based oligonucleotides that selectively bind and cleave specific target RNAs. Due to their potential for specifically inhibiting gene expression, ribozymes are being investigated for therapeutic applications as well as for the elucidation of gene function. In particular, we have investigated ribozymes that target the mRNA of the vascular endothelial growth factor (VEGF) receptors because VEGF signaling is an important mediator of tumor angiogenesis and metastasis. Here we report pharmacodynamic studies testing anti-Flt-1 (VEGFR-1) and anti-KDR (VEGFR-2) ribozymes in animal models of solid tumor growth and metastasis. Ribozymes targeting either Flt-1 or KDR significantly inhibited primary tumor growth in a highly metastatic variant of Lewis lung carcinoma. However, only treatment with the anti-Flt-1 ribozyme resulted in a statistically significant and dose-dependent inhibition of lung metastasis in this model. The anti-Flt-1 ribozyme was then tested in a xenograft model of human metastatic colorectal cancer in which significant inhibition of liver metastasis was observed. Taken together, these data represent the first demonstration that synthetic ribozymes targeting VEGF receptor mRNA reduced the growth and metastasis of solid tumors in vivo.

Inhibition of hepatitis C virus (HCV)-RNA-dependent translation and replication of a chimeric HCV poliovirus using synthetic stabilized ribozymes

Ribozymes are catalytic RNA molecules that can be designed to cleave specific RNA sequences. To investigate the potential use of synthetic stabilized ribozymes for the treatment of chronic hepatitis C virus (HCV) infection, we designed and synthesized hammerhead ribozymes targeting 15 conserved sites in the 5' untranslated region (UTR) of HCV RNA. This region forms an internal ribosome entry site that allows for efficient translation of the HCV polyprotein. The 15 synthetic ribozymes contained modified nucleotides and linkages that stabilize the molecules against nuclease degradation. All 15 ribozymes were tested for their ability to reduce expression in an HCV 5' UTR/luciferase reporter system and for their ability to inhibit replication of an HCV-poliovirus (HCV-PV) chimera. Treatment with several ribozymes resulted in significant down-regulation of HCV 5' UTR/luciferase reporter expression (range 40% to 80% inhibition, P <.05). Moreover, several ribozymes showed significant inhibition (>90%, P <.001) of chimeric HCV-PV replication. We further show that the inhibitory activity of ribozymes targeting site 195 of HCV RNA exhibits a sequence-specific dose response, requires an active catalytic ribozyme core, and is dependent on the presence of the HCV 5' UTR. Treatment with synthetic stabilized anti-HCV ribozymes has the potential to aid patients who are infected with HCV by reducing the viral burden through specific targeting and cleavage of the viral genome.

Widespread occurrence of a highly conserved RING-H2 zinc finger motif in the model plant Arabidopsis thaliana

Several novel Arabidopsis thaliana proteins containing a RING-H2 zinc finger motif were predicted after database searches. Alignment of 29 RING-H2 finger sequences shows that the motif is strikingly conserved in otherwise unrelated proteins. Only short, non-conserved polar/charged sequences distinguish these domains. The RING-H2 domain is most often present in multi-domain structures, a number of which are likely to contain a membrane-spanning region or an additional zinc finger. However, there are several small (126-200 residues) proteins consisting of an N-terminal domain, rich in aliphatic residues, and a C-terminal RING-H2 domain. Reverse-transcription PCR suggests that the RING-H2 genes are widely expressed at low levels.

Shoulder arthroplasty in recreational golfers

A retrospective review of 24 patients who had shoulder arthroplasty revealed that 23 were able to resume playing golf. The 23 patients (mean age 52.4 years, range 26.4 to 71.9 years) underwent 26 shoulder arthroplasties, 20 total shoulder arthroplasties, and 6 hemiarthroplasties. The average follow-up was 53.4 months (range 24.4 to 127.2 months). The average length of time from shoulder arthroplasty to playing an entire round of golf was 4.5 months. Eighteen patients were able to report their preoperative handicap and noted an average improvement after surgery of almost 5 strokes. Playing golf did not result in increased radiographic evidence of component loosening, and no increase occurred in lucent lines when the golfers were compared with a control group of 76 patients with osteoarthritis who had 103 shoulder arthroplasties (P < .05). Fifty members of the American Shoulder and Elbow Society were mailed a standardized questionnaire of 11 questions concerning patients who had shoulder arthroplasty and played golf. Most surgeons (91%) encouraged such patients to resume playing golf. The average length of time members of the Society recommended that patients should wait after shoulder arthroplasty before resuming golf was 4.3 months. Approximately 60% of surgeons believed that no limit should be placed on the number of golf rounds played weekly, and 91% denied an increase in complications among those who returned to playing golf after undergoing shoulder arthroplasty. Fewer than one third of the surgeons (29.5%) believed that component wear would be a problem in patients who undergo shoulder arthroplasty and play golf frequently and would recommend a hemiarthroplasty for an active golfer because of concern about future glenoid problems.

Phosphoinositide 3-kinase activity is necessary for insulin-dependent inhibition of apolipoprotein B secretion by rat hepatocytes and localizes to the endoplasmic reticulum

Insulin inhibits apolipoprotein B (apoB) secretion by primary rat hepatocytes through activation of phosphoinositide 3-kinase (PI 3-K). Current studies demonstrate that the PI 3-K inhibitor wortmannin inhibits both basal and insulin-stimulated PI 3-K activities. Wortmannin and LY 294002, two structurally distinct PI 3-K inhibitors, prevent insulin-dependent inhibition of apoB secretion in a dose-dependent manner. To link PI 3-K activation to insulin action on apoB, we investigated whether insulin induced localization of activated PI 3-K to the endoplasmic reticulum (ER), where apoB biogenesis is initiated. Insulin action results in a significant redistribution of PI 3-K to a low density microsome (LDM) fraction containing apoB protein and apoB mRNA. Insulin stimulates a significant increase in PI 3-K activity associated with insulin receptor substrate-1 as well as an increase in insulin receptor substrate-1/PI 3-K mass in LDM. Subfractionation of LDM on sucrose density gradients shows that insulin significantly increases the amount of PI 3-K present in an ER fraction containing apoB. Insulin stimulates PI 3-K activity in smooth and rough microsomes isolated from rat hepatocytes, the latter of which contain rough ER as demonstrated by electron microscopy. Studies indicate that 1) PI 3-K activity is necessary for insulin-dependent inhibition of apoB secretion by rat hepatocytes; 2) insulin action leads to the activation and localization of PI 3-K in an ER fraction containing apoB; and 3) insulin stimulates PI 3-K activity in the rough ER.

Transvaginal ultrasound, endometrial cytology sampled by Gynoscann and histology obtained by Uterine Explora Curette compared to the histology of the uterine specimen. A prospective study in pre- and postmenopausal women undergoing elective hysterectomy

BACKGROUND

The purpose of this study was to evaluate the diagnostic value of transvaginal ultrasound measurement of endometrial thickness, cytology obtained by Gynoscann, and histology of the endometrium sampled by Uterine Explora Curette compared with histology of the uterine specimen as the gold standard.

METHODS

Consecutive patients admitted for hysterectomy had transvaginal ultrasound, sampling by Gynoscann, and Uterine Explora Curette done just before surgery, after informed consent.

RESULTS

A total of 181 women entered the study. Sixteen had endometrial cancer, seven had atypical hyperplasia and nine had complex hyperplasia. A total of 168 patients had a transvaginal ultrasound done. At a cutoff limit of 4mm (endometrial thickness of 4mm or less indicating normal endometrium), the sensitivity was 90.3%, the specificity 24.8%, the positive predictive value 21.4% and the negative predictive value 91.9%. One endometrial cancer, one atypical and one complex hyperplasia were missed. The Gynoscann method showed a sensitivity of 62.5%, a specificity of 94.0%, a positive predictive value of 69.0% and a negative predictive value of 92.1%. Two cancers, three atypical and six complex hyperplasia were missed. The Uterine Explora Curette showed a sensitivity of 90.6%, a specificity of 100.0%, a positive predictive value of 100.0% and a negative predictive value of 98.0%. One endometrial cancer and two complex hyperplasia were missed.

CONCLUSION

Transvaginal ultrasound is a reliable method in excluding endometrial pathology. The Uterine Explora Curette was superior to Gynoscann in diagnosing neoplasia of the endometrium. It was found to have the same diagnostic accuracy as conventional dilatation and curettage.

[Randomized clinical trials in the Ugeskrift for Laeger 1948-1995]

The Danish Medical Journal (Ugeskrift for Laeger) was handsearched for randomised and pseudorandomised clinical trials over the years 1948-1995. We found 665 trials of which 539 (81%) were classified as randomised; the randomisation method was not stated for 422 of them (78%) and was insufficiently described in the majority of the rest. This problem became worse with time (p = 0.01). In contrast to the international literature where the increase was more gradual and occurred several years later, the number of randomised trials increased markedly around 1973. This change is associated with the introduction of courses in clinical research methodology during the previous years. Since randomisation is the most important safeguard against bias, the method should be described in detail.

Delayed primary repair of a kyrogenic spinal accessory nerve injury: a case report

The course of the accessory nerve through the posterior cervical triangle is superficial and in close juxtaposition to the posterior cervical lymph node chain. These anatomic features contribute to the common occurrence of kyrogenic injury to the accessory nerve. Unfortunately, the diagnosis of this injury often is delayed because the clinical presentation may mimic shoulder impingement or adhesive capsulitis. The authors present a case with a 15-year followup of a 48-year-old woman who underwent successful delayed primary repair of an accessory nerve injury after a lymph node biopsy. Electromyographic examination is recommended at 3 weeks after a suspected accessory nerve lesion, and if evidence of trapezial denervation is present, early surgical exploration is indicated because spontaneous recovery is rare.

A comparison of three-dimensional computed tomography scans and stereolithographic models for evaluation of craniofacial anomalies

PURPOSE

This article describes the use of stereolithographic (SL) models as an adjunct to treatment planning in patients with Apert's syndrome, scaphocephaly, brachycephaly, and turricephaly.

PATIENTS AND METHODS

Four syndrome patients had computed tomography (CT) scans done presurgically, and one of these patients was additionally scanned postoperatively. SL models and three-dimensional (3D) CT image reconstructions were produced from the CT data, and linear measurements were compared between the two modalities.

RESULTS

All cases showed mean differences between measurements with 3D-CT and SL models of -0.3 to 0.8 mm, except on the CT scans with a gantry tilt (-1.7 mm) and the brachycephalic patient in whom larger deviations were demonstrated (-9.5 mm).

CONCLUSION

The results of the study indicate that the accuracy of the SL technique is not always sufficient, necessitating additional validation studies before it can be recommended for routine clinical use.

Proximal humeral reconstruction after excision of a primary sarcoma

From 1978 to 1991, 19 patients underwent wide resection of the proximal humerus for a primary bone tumor. Reconstructions included intercalary autoclaved autograft and Neer prosthesis composites in 11 patients, intercalary allograft and Neer prosthesis composites in 4 patients, and a Neer prosthesis with methylmethacrylate in 4 patients. All patients were observed for at least 2 years or until death. The functional results and complications of the 19 procedures were evaluated. Function was rated as excellent for 17 patients and good for 2 patients. There were no failures of fixation. Local recurrence occurred in 2 patients. There were 2 cases of recurrent anterior subluxation and 1 of dislocation. Two superficial wound infections were treated successfully with local debridement and antibiotics. The authors conclude that autoclaved autograft or allograft when combined with a long-stem cemented Neer prosthesis offers an excellent composite for proximal humeral reconstruction.

Type II collagen is transiently expressed during avian cardiac valve morphogenesis

We present new evidence of the temporal and spatial expression of type II collagen in the embryonic chick heart during the very early stages of its development. In particular, we emphasize the distribution of its mRNA and protein during valve formation. Type II collagen as well as several other fibrillar collagens (types I, III, and V) are present in stage 18 endocardial cushion mesenchymal cells. At stage 23, alpha 1 (II) collagen transcripts and the cognate polypeptide colocalize in the atrioventricular valves. As development proceeds, the relative abundance of alpha 1 (II) collagen transcripts decreases during the stages studied (stages 22 to 45; day 3.5 to day 19) as assayed by RNA blotting of extracts of whole hearts. Type II collagen protein was immunologically undetectable in stage 38 (day 12) hearts, although collagens I, III, and V persisted and localize in the valve regions, in the endothelial lining of the heart, and in the epicardium. In keeping with other observations of type II collagen expression in non-chondrogenic regions of a variety of vertebrate embryos, the avian heart also exhibits transient type II collagen expression.

Myogenic cytodifferentiation of the precardiac mesoderm in the rat

The contractile cells of the primitive heart are derived from a subpopulation of the lateral plate splanchnic mesoderm. While the formation of the cardiac primordia has been studied in the avian embryo, little is known about this cell population in the mammal. To investigate the distribution and cellular differentiation of the myocardial precursors in the early mammalian embryo, we studied the sequential immunohistochemical appearance of desmin and myosin in whole mounts of rat embryos from the presomite (gestational day 9) through the 6-8 somite, straight heart tube (gestational day 10) stages of early cardiac morphogenesis. In contrast to the chicken, and previous reports in the mouse, our results show that myogenic differentiation of the muscle precursor cells of the heart begins in the presomite embryo prior to formation of the anterior intestinal portal or foregut. In addition, this cell population of the precardiac mesoderm appears as a single crescent-shaped population of cells in continuity across the midline which extends caudally during development and then fuses in the midline to form the primitive heart tube. Unlike skeletal myogenesis, desmin and myosin appear simultaneously and are codistributed throughout this initial period of heart development. These results suggest that myocardial differentiation in the rat is precocious when compared to the chicken and precedes the morphogenetic processes involved in formation of the primitive heart tube. Furthermore, this study provides the first description in the mammal of the spatial distribution of the myogenic precardiac mesoderm.

Prospective randomized comparison of two types of pressure therapy garments

A prospective randomized study was undertaken to compare compliance efficacy and cost of the elastic nylon pressure garment (Jobst Institute, Inc., Toledo, Ohio) with the cotton elastic pressure garment (Tubigrip, SePro Healthcare Inc., Montgomeryville, Penn.). Of 110 patients enrolled, 54 received Jobst pressure garments and 56 received Tubigrip pressure garments. Time spent in pressure-therapy garments was the same for both groups. Comparable clinical results were achieved with either Tubigrip or Jobst garments. A significantly greater percentage of patients were compliant with Tubigrip pressure-garment therapy than with Jobst pressure-garment therapy. The cost of the Tubigrip garments was significantly lower than that of Jobst garments. These data suggest that the use of elasticized cotton pressure garments results in significantly better patient compliance, a lower cost, and equal therapeutic efficacy when compared with the elasticized nylon pressure garments.

Transient expression of a cell surface heparan sulfate proteoglycan (syndecan) during limb development

Syndecan is an integral membrane proteoglycan that contains both heparan sulfate and chondroitin sulfate chains and that links the cytoskeleton to interstitial extracellular matrix components, including collagen and fibronectin. Immunohistochemistry with a monoclonal antibody directed to the core protein of the syndecan ectodomain has been used to analyze the distribution of this proteoglycan in the developing mouse limb bud and in high-density cultures of limb mesenchyme cells. By Day 9 of gestation when the limb buds are just apparent, syndecan is detected on cells throughout the limb region, including both ectodermal and mesenchymal components. This distribution does not change as the limb bud elongates along its proximodistal axis, except for its reduction in the apical ectodermal ridge. By Day 11, the intensity of immunofluorescence in the central core decreases relative to other regions. By Day 13 immunostaining is lost in the regions destined for chondrogenesis and myogenesis but persists in the limb ectoderm and peripheral and distal mesenchyme. In the limb mesenchyme cell cultures, syndecan is initially undetected, but is found throughout the culture by 24 hr. With further culture the antigen becomes reduced in chondrogenic foci and in association with myogenic cells. When chick limb ectoderm is placed on the high-density cultures, immunoreactivity in the mouse mesenchyme is enhanced suggesting that epithelial-mesenchymal interactions modulate syndecan expression in the limb bud. Based on analysis of 35S-labeled syndecan from the cultures, syndecan from limb mesenchyme cells contains more glycosaminoglycan chains and is larger in size than the previously described polymorphic forms of syndecan from various epithelia. The high affinity of syndecan for components of the extracellular matrix and its distribution in the early limb bud are consistent with a role in maintaining the morphologic integrity of the limb bud during the period of initiation and rapid outgrowth, and in preventing the onset of chondrogenesis.

The distribution of mesenchyme proteoglycan (PG-M) during wing bud outgrowth

This study utilizes immunofluorescence to describe the distribution of several extracellular matrix molecules in the chick embryo during the process of limb outgrowth and the formation of precartilage condensations. A large chondroitin sulfate proteoglycan (PG-M) is detected at the wing level at Hamburger and Hamilton stage 14 in and under the dorsal ectoderm, and is associated with the basement membranes around the neural tube, notochord and pronephros, but not with other basement membranes. The galactose-specific lectin, peanut agglutinin (PNA), has a similar distribution except that it also binds to the dorsal side of the neural tube. PG-M is not detected in the limb mesenchyme until after stage 17, when it is present in the distal region, as is PNA-binding material. With further development of the wing bud, PG-M is present in the subectodermal mesenchyme, the mesenchyme at the distal tip and in the prechondrogenic core. After stage 22 PNA-binding material becomes localized in the prechondrogenic core, the basement membranes under the apical ectodermal ridge, and the ventral sulcus. The distribution of these components (PG-M and PNA binding material) overlaps, but differs from that of type I collagen and fibronectin and basement membrane components, such as laminin, basement membrane heparan sulfate proteoglycan, and type IV collagen. Tenascin, on the other hand, is not detected in the limb bud until stage 25, after the appearance of cartilage matrix components such as type II collagen and cartilage proteoglycan (PG-H). These results are considered in relation to the formation of precartilage aggregates, and indicate that PNA binds to components in precartilage aggregates other than PG-M or tenascin.

[The effect of anabolic androgenic steroids on muscle strength, body weight and lean body mass in body-building men]

A review of the effects of anabolic-androgenic steroids (AAS) on muscle strength, body weight and lean body mass in body-building men is presented. In about half of the placebo-controlled studies, a significant effect on the above mentioned response variables is found. In all cases where an effect was achieved, the drug used was methandrostenolone or stanozolol. Whether this is connected with a special quality of these AAS or whether the negative results achieved with the other AAS are caused by type 2 error is not yet known. The use of AAS as ergogenic drugs must be deprecated because of their marginal effects, the risks of side effects and the unsporting, unethical aspects.

The accumulation of basement membrane components during the onset of chondrogenesis and myogenesis in the chick wing bud

The study describes the distribution of several basement membrane molecules in the embryonic chick wing bud from stages 23 to 26, during the onset of myogenesis and chondrogenesis, and then later at stage 28. Laminin is localized as early as stage 23, prior to the onset of myogenesis, in regions corresponding to the position of the future dorsal and ventral myogenic areas. Other matrix components, including fibronectin, do not differentially accumulate in these same regions. Fibronectin, basement membrane heparan sulphate proteoglycan and type IV collagen are more widespread in their distribution than laminin, and are even present between mesenchymal cells. These results suggest a role for laminin in the initial differentiation of the muscle masses and emphasize that components of basement membrane can also be associated with mesenchymal cells.

Environmental regulation of type X collagen production by cultures of limb mesenchyme, mesectoderm, and sternal chondrocytes

We have examined whether the production of hypertrophic cartilage matrix reflecting a late stage in the development of chondrocytes which participate in endochondral bone formation, is the result of cell lineage, environmental influence, or both. We have compared the ability of cultured limb mesenchyme and mesectoderm to synthesize type X collagen, a marker highly selective for hypertrophic cartilage. High density cultures of limb mesenchyme from stage 23 and 24 chick embryos contain many cells that react positively for type II collagen by immunohistochemistry, but only a few of these initiate type X collagen synthesis. When limb mesenchyme cells are cultured in or on hydrated collagen gels or in agarose (conditions previously shown to promote chondrogenesis in low density cultures), almost all initiate synthesis of both collagen types. Similarly, collagen gel cultures of limb mesenchyme from stage 17 embryos synthesize type II collagen and with some additional delay type X collagen. However, cytochalasin D treatment of subconfluent cultures on plastic substrates, another treatment known to promote chondrogenesis, induces the production of type II collagen, but not type X collagen. These results demonstrate that the appearance of type X collagen in limb cartilage is environmentally regulated. Mesectodermal cells from the maxillary process of stages 24 and 28 chick embryos were cultured in or on hydrated collagen gels. Such cells initiate synthesis of type II collagen, and eventually type X collagen. Some cells contain only type II collagen and some contain both types II and X collagen. On the other hand, cultures of mandibular processes from stage 29 embryos contain chondrocytes with both collagen types and a larger overall number of chondrogenic foci than the maxillary process cultures. Since the maxillary process does not produce cartilage in situ and the mandibular process forms Meckel's cartilage which does not hypertrophy in situ, environmental influences, probably inhibitory in nature, must regulate chondrogenesis in mesectodermal derivatives. (ABSTRACT TRUNCATED AT 250 WORDS)

Extracellular matrix mediates epithelial effects on chondrogenesis in vitro

It has been previously observed that single chick embryonic limb mesenchymal cells can differentiate into chondrocytes without cell-cell interactions when cultured in collagen or agarose gels. In the present study, limb ectoderm, but not dermis, inhibits chondrogenesis when placed on such collagen gel cultures. The inhibitory influence can be transmitted extensive distances in the gel, even when the ectoderm is placed on a porous filter. Collagen gels, preconditioned with limb ectoderms, are also inhibitory to chondrogenesis. On the other hand, chondrogenesis is less inhibited by ectoderm when the mesenchymal cells are placed in agarose. These results suggest that the antichondrogenic effect of limb ectoderm is mediated through alterations of the collagenous extracellular matrix and support the idea that the extracellular matrix must be considered as an organized, functional unit capable of regulating cell differentiation.

Histiomonocytic malignancy. A spectrum of disease in an 11-month-old infant

The initial pathologic diagnosis in an 11-month-old girl presenting with a suprarenal mass was true histiocytic lymphoma. The histiocytic nature of the cells was verified by ultrastructural, histochemical, and immunologic studies. The subsequent course featured widespread dissemination as both tumorous masses and diffuse tissue infiltrates, including extensive soft tissue, leptomeningeal, and bone marrow involvement, with a terminal histiomonocytic leukemic phase. Subsequently, this tumor was reclassified as malignant histiocytosis with atypical features, and this case exemplifies the difficulties in classifying some malignant histiomonocytic neoplasms. The overlapping clinical, pathologic, and theoretic features of true histiocytic lymphoma, malignant histiocytosis, and histiomonocytic leukemia are discussed in the context of this case.