Redefining the phenotypic spectrum of de novo heterozygous CDK13 variants: Three patients without cardiac defects

Recently, 7 patients with de novo constitutional non-synonymous mutations in the CDK13 gene were ascertained through a trio exome analysis of a large cohort of 610 patients with congenital cardiac diseases. Despite another report describing 9 additional patients, the clinical spectrum of this condition has yet to be defined. Herein, we report 3 patients with heterozygous constitutional CDK13 mutations, who were ascertained through exome analysis of children with intellectual disability and minor anomalies, who lacked cardiac anomalies. Two patients had a c.2149G > A, p.Gly717Arg mutation, and one had a c.2525A > G, p. Asn842Ser mutation. A review of the previously described patients and those described herein has enabled the following points to be clarified. First, congenital heart diseases are not an essential feature (13/19). Second, nasal features may help syndromic recognition (14/16). Third, widely spaced and peg-shaped teeth may represent a previously unappreciated diagnostic clue for this newly identified syndrome. Here, we show that p.Gly717Arg represents a hotspot in addition to p.Asn842Ser. We suggest that this CDK13-related disorder may represent a clinically recognizable syndrome.     

Double-Expressor Lymphoma Is Associated with Poor Outcomes after Allogeneic Hematopoietic Cell Transplantation

Double-expressor lymphoma (DEL) is a diffuse large B cell lymphoma that exhibits co-expression of MYC and BCL2 proteins by immunohistochemistry. Patients with double-expressor lymphoma have a poor prognosis after standard chemoimmunotherapy or after high-dose chemotherapy with autologous transplantation, but the prognostic impact of DEL after allogeneic hematopoietic cell transplantation has not been well characterized. We retrospectively analyzed 60 consecutive patients with de novo diffuse large B cell lymphoma or transformed follicular lymphoma who underwent allogeneic transplantation at our center and had available immunohistochemistry data. Thirty-seven patients (62%) had DEL. The 2-year progression-free and overall survival rates were lower in patients with DEL than in those without DEL (20% versus 78%; overall P?<.001 and 46% versus 77%; overall P?=?.016, respectively). The cumulative incidence of disease progression at 2 years was higher in patients with DEL (60% versus 13%; overall P?=?.005). The cumulative incidence of nonrelapse mortality did not differ statistically in the 2 groups. Even in patients with DEL and chemosensitive disease at transplantation, the 2-year progression-free survival rate was only 27% due to early disease progression. Multivariate analysis showed associations between DEL and increased risks of progression-free survival events (hazard ratio [HR], 4.58; 95% confidence interval [CI], 2.07-10.2; P?<.001), overall mortality (HR, 2.29; 95% CI, 1.03-5.09; P?=?.042) and disease progression (HR, 3.60; 95% CI, 1.38-9.44; P?=?.009). Patients with DEL had poor outcomes after allogeneic transplantation. Innovative strategies are needed to improve outcomes in this population.     

Hepatocyte growth factor prevents renal fibrosis and dysfunction in a mouse model of chronic renal disease.

Chronic renal disease (CRD) is generally thought to be incurable, except through renal transplantation, and the number of patients with CRD is on the increase. Glomerulosclerosis and tubulointerstitial fibrosis represent the morphological equivalent of end-stage CRD. In this study, we demonstrated the preventive effect of hepatocyte growth factor (HGF) on the progression of renal dysfunction and fibrosis, using a spontaneous mouse model for CRD (ICGN strain). The mice progressively developed glomerular sclerotic injury, tubular atrophy, and renal dysfunction until they were 17 wk of age. When recombinant HGF was injected into these mice during a 4-wk-period (from weeks 14-17 after birth), DNA synthesis of tubular epithelial cells was found to be 4.4-fold higher than in mice without HGF injection, thereby suggesting tubular parenchymal expansion promoted by HGF. Notably, HGF suppressed the expression of transforming growth factor-beta and of platelet-derived growth factor as well as myofibroblast formation in the affected kidney. Consequently, the onset of tubulointerstitial fibrosis was almost completely inhibited by HGF, while HGF attenuated the progression of glomerulosclerosis, both leading to preventing manifestation of renal dysfunction. From our results, supplement therapy with HGF may be taken into consideration as a novel option for prevention and treatment of CRD.     

No specific organ removes atrial natriuretic peptide from the human plasma

The fate of atrial natriuretic peptide (ANP) was studied by arterial and venous catheterization in ischemic heart disease patients, and arterio-venous blood sampling in healthy kidney donors at the time of transplantation. In vitro ANP degradation was examined using healthy human plasma. In ischemic heart disease, the plasma ANP concentration at the inferior vena cava was 62.6% of that at the left ventricle, and that at the superior vena cava was 82.8%. Arterio-venous gradients were similar from pulmonary artery to vein (88.3%), from celiac artery to the hepatic vein (75.5%) and from the femoral artery to vein (85.4%). In the donor for kidney transplantation, renal arterio-venous gradient was also similar at 77.1%. No platelet consumption of ANP was noted, and the molecular forms of ANP present in the circulation were similar in samples obtained from both the coronary sinus and the superior or inferior vena cava. We conclude that no specific organ plays a dominant role in ANP degradation, and that ANP molecular forms may not be altered during circulation.     

The reducing effect of prostaglandins on circulating eosinophils in splenectomized rats--on its mechanism (author's transl)]

It is known that Prostaglandins(PGs) have many interesting physiological effects on various tissues, but the reducing effect on circulating eosinophils was still obscure, except for our report in 1975. Our previous report revealed that the effect had not act through beta-adrenergic receptors, because a beta-adrenergic blocker did not inhibit this effect. The present report was carried out to study whether the hypothalamo-hypophyseal-adrenocortical axis would be concerned or not on this effect. PGs(10 mug/kg) were administered intraperitoneally under thiopental sodium anesthesia and blood was drawn from the tail vein of the splenectomized rats. Both PGE1, E2, F2alpha did not decrease the number of peripheral eosinophils on the group of the adrenalectomized rats. Both PGE1, F2alpha did not decrease the number of peripheral eosinophils, but PGE2 had a significant reducing effect on the number of them 2 and 3 hours after administration in the group of the rats with hypothalamic lesions. Both PGE1, E2, F2alpha had a significant reducing effect at the group of the rats with man-made hypothalamic lesions. This effect was almost the same as for the control group just splenectomized. It could be concluded that the eosinopenic effect of PGE1 and PGF2alpha was conducted through the hypothalamus and adrenal glands, but that of PGE2 might be effected through the hypophysis or directly through the adrenal glands.     

Discrepancy between auditory brainstem responses, auditory steady-state responses, and auditory behavior in two patients with Pelizaeus-Merzbacher disease

We reported two cases of Pelizaeus-Merzbacher disease. Both cases visited our hospital manifesting horizontal nystagmoid movements present from birth, and delayed motor development. Magnetic resonance imaging of the brain showed diffuse dysmyelination of the cerebral white matter, and auditory brainstem response showed waves I and II but absence of all subsequent components. Conditioned orientation reflex (COR) audiometry showed poor reactions in an infantile case whose development was severely retarded, and who spoke no meaningful words. Auditory steady-state response (ASSR) was a helpful tool for identifying her auditory ability; thereafter, her communication skills improved naturally. The other case was mildly developmentally retarded, and the results of COR audiometry and ASSR were considered the same level. The discrepancy between results of these hearing tests may arise under the influence of developmental level of the case.