T-lymphocyte subsets in recurrent aphthous ulceration

Peripheral T-lymphocyte subsets: T-helper (OKT4) and T-suppressor (OKT8) cells were studied quantitatively in 20 patients with recurrent aphthous ulceration (RAU) in ulcerative, as well as inactive, stages of the disease. The figures were compared with T-lymphocyte subsets from matched control donors with no history of RAU. The ratio of T-helper: T-suppressor cells was significantly lower in both stages in the patients compared with controls due to a significantly increased number of T-suppressor cells in RAU patients. The number of T-helper cells in the patients did not differ significantly in either stage compared with controls. The study support the hypothesis of recurrent aphthous ulceration being a disorder of immunodeficiency.     

Pseudomonas aeruginosa biofilm hampers murine central wound healing by suppression of vascular epithelial growth factor

Biofilm‐infected wounds are clinically challenging. Vascular endothelial growth factor and host defence S100A8/A9 are crucial for wound healing but may be suppressed by biofilms. The natural course of Pseudomonas aeruginosa biofilm infection was compared in central and peripheral zones of burn‐wounded, infection‐susceptible BALB/c mice, which display delayed wound closure compared to C3H/HeN mice. Wounds were evaluated histopathologically 4, 7 or 10 days post‐infection. Photoplanimetry evaluated necrotic areas. P. aeruginosa biofilm suppressed vascular endothelial growth factor levels centrally in BALB/c wounds but increased peripheral levels 4–7 days post‐infection. Central zones of the burn wound displayed lower levels of central vascular endothelial growth factor as observed 4 and 7 days post‐infection in BALB/c mice compared to their C3H/HeN counterparts. Biofilm suppressed early, centrally located S100A8/A9 in BALB/c and centrally and peripherally later on in C3H/HeN wounds as compared to uninfected mice. Peripheral polymorphonuclear‐dominated inflammation and larger necrosis were observed in BALB/c wounds. In conclusion, P. aeruginosa biofilm modulates wounds by suppressing central, but inducing peripheral, vascular endothelial growth factor levels and reducing host response in wounds of BALB/c mice. This suppression is detrimental to the resolution of biofilm‐infected necrosis.     

Stimulation of Monovalent Cation Active Transport by Low Concentrations of Cardiac Glycosides: ROLE OF CATECHOLAMINES

The stimulatory effect of low concentrations of ouabain on the Na-K pump in isolated guinea pig left atria was studied in vitro by assessing active transport of the K⁺ analog Rb⁺. Active transport of Rb⁺ was stimulated 20±8% (SEM, P < 0.05) above control values by 3 nM ouabain, but was inhibited by concentrations >10 nM. Preincubation with the β-adrenergic antagonist propranolol (1 μM) completely blocked stimulation of active transport of Rb⁺ by 3 nM ouabain. Norepinephrine, 10 nM, increased Rb⁺ active transport 29±10% (P < 0.02) above control values. The β-adrenergic agonist l-isoproterenol, 10 nM, increased active transport of Rb⁺ by 33±10% (P < 0.01) above control levels. This stimulatory effect was abolished if tissues were first exposed to propranolol. Tyramine (0.1 μM), a stimulator of endogenous catecholamine release, increased active transport of Rb⁺ 26±12% (P < 0.05) above control values. Rb⁺ active transport was not significantly changed when left atrial tissues were incubated with α-adrenergic agonists or antagonists. Ouabain stimulation of Rb⁺ active transport was prevented by in vivo depletion of myocardial endogenous catecholamines by either reserpine or 6-hydroxydopamine. These findings indicated that in myocardial tissue, Na-K pump stimulation by low concentrations of ouabain is mediated at least in part through β-adrenergic effects of endogenous catecholamines.     

Asphyxia homicides in Denmark 1992–2016

In this retrospective study , we present the findings in 250 homicides by asphyxia in Denmark in a 25-year period, with a particular focus on the autopsy findings in strangulation. Our intention is for the results to be used in future death investigations, where difficulties in interpretation of findings in potential asphyxial deaths arise. Asphyxia homicides showed a strong bias with respect to sex, age, and homicide type. The frequent female victim was typically an adult, whereas the rarer male victim was most often a child. Female offenders most often killed their children, and male offenders most often killed their female partner. Generally, most asphyxia homicides took place in a domestic setting. Manual strangulation and ligature strangulation were the most common mechanisms of asphyxia homicides (81.6%). A lack of petechial hemorrhages, especially in the conjunctiva, was rare in homicidal strangulation, but there were exceptions, especially when there was postmortem decomposition, making it impossible to verify them. Most victims of strangulation had skin lesions in the face (including the jawline) or on the neck, with accompanying hemorrhages in muscle and connective tissue, but the findings could be subtle or compounded by decomposition. Fractures of the laryngo-hyoid complex were common in strangulation, particularly in manual strangulation (chi-sq = 4.0993, df = 1, P < 0.05) and were clearly related to the age of the victim (chi-sq = 82.193, df = 4, P < 0.001). In children and young adults dying from homicidal strangulation, a lack of fractures is to be expected, while a lack of fractures is unusual, but not entirely unexpected, for adults and aged people.

     

The thymus reconstituted nude rat: lymphocyte subpopulations and immunological characteristics

The monoclonal antibodies OX6, OX19, W3/13, OX7, OX8, and W3/25 were used to gain information about the distribution of different lymphocyte subpopulations in peripheral lymphoid organs of neonatally isogeneic and allogeneic thymus reconstituted nude rats. Splenic mitogen responsiveness, xenogeneic skin rejection, and antibody titers were also measured in the same groups of animals. The experiments showed that both allogeneic and isogeneic thymus grafting cause a significant amplification of cells in the different T lymphocyte subpopulations. The functional tests, however, indicate that the T cell response is far better following isografting. We, therefore, conclude that isogeneic thymus grafting is an easy method of reconstituting the nude rat immunologically.     

Cardiovascular findings in adolescent inpatients with anorexia nervosa

Left ventricular function, resting electrocardiograms, and Holter recordings were systematically examined in 25 consecutively hospitalized, seriously ill, emaciated adolescents with anorexia nervosa. We failed to observe serious arrhythmias, abnormal prolongation of QT interval, conduction abnormalities, or depression in left ventricular systolic function.     

Dual balloon technique for valvuloplasty of aortic stenosis in adults

A dual balloon technique was studied in 16 patients with aortic stenosis in whom results with a single balloon (up to 20 mm, 5.5 cm or 25 mm, 3.0 cm in diameter and length, respectively) were judged to be suboptimal. Dual balloon valvuloplasty was performed using 2 balloons advanced and inflated simultaneously across the stenotic aortic valve orifice. For the group as a whole, the average peak transvalvular gradient was reduced from 79 +/- 8 to 57 +/- 7 mm Hg (mean +/- standard error) using a single balloon (p less than 0.0005), and reduced further to 36 +/- 4 mm Hg using dual balloons (p less than 0.0005 compared with single balloon results). Similarly, calculated aortic valve orifice area was increased from 0.45 +/- 0.04 to 0.57 +/- 0.05 cm2 using a single balloon (p less than 0.0005), and further increased to 0.77 +/- 0.06 cm2 using dual balloons (p less than 0.0005). Dual balloon dilation caused no complications directly attributable to the use of 2 balloons, including no exacerbation of aortic regurgitation. These results suggest that dual balloon valvuloplasty is safe and efficacious in selected patients with aortic stenosis.     

Cor triatriatum associated with partial anomalous pulmonary venous connection to the coronary sinus: Echocardiographic and angiocardiographic features

Summary An infant girl is described who had cor triatriatum and partial anomalous pulmonary venous connection of the left pulmonary veins to the coronary sinus, the first report of this combination of lesions. The infant also had a Dandy-Walker malformation and multiple facial and intrathoracic hemangiomas. The cardiac diagnosis was made by two-dimensional echocardiography. Cardiac catheterization and angiography confirmed the findings and also demonstrated a persistent left superior vena cava draining to the coronary sinus. The infant underwent successful surgical repair. Partial anomalous pulmonary venous connection and left superior vena cava not infrequently are associated with cor triatriatum. Although two-dimensional echocardiography is sensitive for the detection of cor triatriatum, preoperative cardiac catheterization is necessary to identify unequivocally systemic and pulmonary venous connections.     

Identification of the mononuclear cell infiltrate in the superior cervical ganglion of athymic nude and euthymic rats after guanethidine-induced sympathectomy

Guanethidine sulphate 40 mg/kg intraperitoneally for 14 days induced chromatolysis and nerve cell death in the superior cervical ganglia of athymic nude (rnu/rnu) LEW/Mol rats and their euthymic (+/rnu) LEW/Mol heterozygous littermates. Histologically the sympathetic ganglia were dominated by an infiltration of small inflammatory cells. By means of monoclonal antibodies these cells were identified. The number of B-lymphocytes increased following guanethidine in both athymic and euthymic rats. The number of T-lymphocytes increased to a great extent in euthymic rats, but was virtually missing in athymic rats. The number of NK-cells and monocytes/macrophages increased in both athymic and euthymic rats. The conclusion is, that guanethidine exerts a direct effect on sympathetic ganglion cells followed by a thymus-independent immune response.