Development Of Constriction Research Articles

Exudative-constrictive tuberculous pericarditis in combination with arthritis in cardiologist practice: thoracoscopic biopsy as a diagnosis and treatment method.

The goal is to present the possibilities of diagnosis verification, the features of the clinical picture of tuberculous pericarditis in the therapeutic clinic and the results of its treatment. The paper presents clinical observation and a general analysis of 10 cases of tuberculous pericarditis in patients aged 31-79 (mean age 58.0 ± 15.1 years), 6 women and 4 men. Diagnostic puncture pericardium was performed on two patients, pleural puncture - on three Thoracoscopic biopsy of hilar lymph nodes and lung (n=1), pleura (n=1), supraclavicular lymph node biopsy (n=1). Dyskin test was carried out, as well as sputum examination, multispiral computed tomography, oncological search. A 31-year-old patient with a massive effusion in the pericardial cavity, pleural lesion, arthritis of the left knee joint, whose results of the pericardial effusion and sputum were not diagnosed, tuberculosis was detected only with thoracoscopic biopsy of the lung and intrathoracic lymph nodes; the treatment via prednisolone and subtotal pericardectomy was performed. Among 10 patients with MSCT of the lung, changes were noted in general, but in only one case they were highly specific. Diaskin test is positive in 70%. In the study of punctata, bronchoalveolar flushing, Koch bacteria were not detected; at sputum in microscopy and biological sample BC was detected in two patients. The lymphocytic character of effusion in the pericardium / pleura is noted in 4 out of 5 cases. At a biopsy of lymphonoduses and a lung at 2 patients the picture of a granulomatous inflammation with a caseous necrosis. Pericarditis was predominantly large (from 2 cm and more) effusion, signs of constriction were noted in 50% of patients. Tuberculosis is one of the frequent causes of pericarditis in the Moscow therapeutic clinic. The most lymphocytic effusion with fibrin and the development of constriction. The negative results of all laboratory tests for tuberculosis do not exclude a diagnosis, It is necessary to use invasive morphological diagnostics, including thoracoscopic biopsy.

Hybrid polymer microfluidic platform to mimic varying vascular compliance and topology.

Several cardiovascular pathologies and aging have been associated with alterations in the mechanical and structural properties of the vascular wall, leading to a reduction in arterial compliance and the development of constriction. In the past, rare efforts have been directed to understand the endothelial cell response to combined mechanical stimuli from fluid flow and substrate rigidity. Recent approaches using microfluidic platforms have limitations in precisely mimicking healthy and diseased vasculature conditions from altered topological and substrate compliance perspectives. To address this, we demonstrated an effective fabrication process to realize a hybrid polymer platform to test these mechanistic features of blood vessels. The salient features of the platform include circular microchannels of varying diameters, variation in substrate rigidity along the channel length, and the coexistence of microchannels with different cross sections on a single platform. The platform demonstrates the combined effects of flow-induced shear forces and substrate rigidity on the endothelial cell layer inside the circular microchannels. The experimental results indicate a pronounced cell response to flow induced shear stress via its interplay with the underlying substrate mechanics.

Surgical Management of Massive Pericardial Effusion and Predictors for Development of Constrictive Pericarditis in a Resource Limited Setting

Background. The diagnosis and treatment of massive pericardial effusion and cardiac tamponade have evolved over the years with a tendency towards a more comprehensive diagnostic workup and less traumatic intervention. Method. We reviewed and analysed the data of 32 consecutive patients who underwent surgery on account of massive pericardial effusion and cardiac tamponade in a semiurban university hospital in Nigeria from February 2010 to February 2016. Results. The majority of patients (34.4%) were between 31 and 40 years. Fourteen patients (43.8%) presented with clinical and echocardiographic feature of cardiac tamponade. The majority of patients (59.4%) presented with haemorrhagic pericardial effusion and the average volume of fluid drained intraoperatively was 846 mL ± 67 mL. Pericardium was thickened in 50% of cases. Subxiphoid pericardiostomy was performed under local anaesthesia in 28 cases. No postoperative recurrence was observed; however 5 patients developed features of constrictive pericarditis. The relationship between pericardial thickness and development of pericardial constriction was statistically significant (p = 0.004). Conclusion. Subxiphoid pericardiostomy is a very effective way of treating massive pericardial effusion. Removing tube after adequate drainage (50 mL/day) and treatment of primary pathology are key to preventing recurrence. There is also a need to follow up patients to detect pericardial constriction especially those with thickened pericardium.

Diabetic vasculopathy in the rat: an in vivo microscopic study of the circulation.

A transparent tissue chamber adapted to the rat back was used for in vivo observation of vascular and circulatory changes in the streptozotocin diabetic rat. The chamber was implanted in a functional and richly vascularized bed of striated muscle. Extensive red cell rouleaux formation was observed within 2-7 days of induction of hyperglycaemia and was closely followed by development of constrictions and dilatations in both venules and arterioles. In 3 of 7 diabetic rats saccular microaneurysms, similar in form to those reported in diabetic animals and humans, developed in the vascular bed. The rat back chamber provides an opportunity for continuous in vivo study of vascular lesions developing in streptozotocin diabetes. Fixation under microscopic observation allows close correlation of functional changes in vivo with the ultrastructural appearance of specific tissue areas.

Primary Meningococcal Pericarditis

Primary meningococcal pericarditis (PMP) is a purulent pericarditis that can rapidly progress to complications, including cardiac tamponade, pericardial constriction, and need for surgical intervention. Risk factors associated with such complications are not well characterized. We describe a case of PMP and analyze all reported cases of PMP to determine whether certain risk factors lead to the development of cardiac tamponade, pericardial constriction, and need for surgical intervention. Twenty-six cases of PMP were identified, of which 23 (88%) developed tamponade, 7 (27%) constriction, and 7 (27%) need for surgical intervention. A positive pericardial fluid culture was associated with the development of tamponade, whereas a delay in antibiotic initiation, more than 24 hours after chest pain onset, was associated with development of constriction and the need for surgical intervention. All cases of constriction required surgical intervention. Early antibiotic administration appears to protect against the development of constriction and subsequent need for surgery.

Constrictive Pericarditis.

Constrictive pericarditis is an uncommon but treatable cause of heart failure that results from a variety of acute inflammatory processes. Corticosteroids appear to prevent the development of constriction in selected patients with active pericardial inflammation. Symptoms of right-sided heart failure usually predominate and can be adequately managed with diuretics. Complete surgical pericardiectomy remains the only definitive treatment. The mortality risk is markedly increased in patients with advanced symptoms, and surgery should be performed in earlier stages. The majority of patients (95% on average) will survive the surgery; complete relief of symptoms occurs in about 50% of survivors. Ten percent of patients will have persistent symptomatic heart failure (New York Heart Association functional class III or IV) and experience poor late outcomes, however, particularly when residual myocardial dysfunction coexists.

Constrictions in cathode-dominated, low-pressure argon discharges

The spatial development of constrictions across the cathode of a low-pressure, quasi-steady-state discharge in argon is recorded as a function of discharge current through the use of charge-coupled device (CCD) camera observations of light emission through a semitransparent anode.

Paleozoic foraminifera

The approximately 300 million years that make up Paleozoic time saw the evolution of eight of the fifteen recognized suborders of Foraminifera. Of the suborders present in the Paleozoic, seven are morphologically relatively simple, slowly evolving, and continued into Mesozoic and Cenozoic times to become the ancestoral lineages from which evolved several additional post-Paleozoic suborders. In contrast, an eighth Paleozoic suborder, the Fusulinina, was an abundant, ecologically dominant group that evolved from simple to highly specialized forms and had a history of rapid evolution with diverse lineages. Fusulinines became extinct at the end of the Paleozoic. Their early representatives may have given rise to three and eventually four post-Paleozoic suborders. A number of suborders in the Paleozoic have similar, supposedly independent, early evolutionary patterns with the following series of morphological steps: (1) single chambers with or without apertures depending on the amount of wall cement; (2) groups of chambers that appear to be buds or aggregations of individuals rather than true chambers; (3) a proloculus followed by a tubular second chamber that is first erect and gradually evolves into enrolled free-living individuals; (4) development of constrictions in the tubular chamber; and finally (5) evolution of true chambers. These morphological steps, which are basic organizational steps with evolutionary significance, appear in lineages with quite different test compositions and, therefore, are considered only distantly related in the present classification.

Cytology of the apex, thallus development and reproductive structures of Hormosira banksii (Fucales, Phaeophyta)

Abstract Light, scanning and transmission electron microscopy have been used to study the initiation of apical growth, the development of constrictions and branching in Hormosira banksii (Phaeophyta). In the early stages of embryogenesis, a single apical cell arises from a cell lying at the base of the apical hairs which grow out of the primary cryptostoma. Mature plants possess four apical cells. The constrictions between the moniliform segments of Hormosira result from the intermittent activity of the apical cells. When the apical cells are inactive the surrounding meristematic region is absent and the terminal segment enlarges due to the development of the medulla. The initiation of new segments is associated with the renewed activity of the apical cells and the surrounding meristematic region. Cryptostomata are arranged in a radial pattern and they all mature into conceptacles. To describe branching in Hormosira as dichotomous is misleading, as two or more branches may arise simultaneously, and succes...

The variable T model for gram-negative morphology.

Gram-negative micro-organisms possess only a very thin murein sacculus to resist the stress caused by the internal hydrostatic pressure. The sacculus consists of at most one molecular layer of peptidoglycan in an extended conformation. It must grow by the insertion and cross-linking of new murein to the old before the selective cleavages of the stress-bearing murein are made which allow wall enlargement. Since insertion of new murein occurs all over the surface of Escherichia coli (even in completed poles), the internal pressure would tend to force the cells into a spherical shape and prevent both cylindrical elongation and cell division. Of course, Gram-negative bacteria do achieve a variety of shapes and do divide. Because prokaryote cells, unlike eukaryotic cells, do not have cytoskeletons and contractile proteins to transduce biochemical free energy into the mechanical work needed to achieve aspherical shapes and to divide, this paradox seems to be resolvable only by postulating that the details of the biochemical mechanism for wall growth vary in different regions of the surface, affecting the work required to enlarge the wall locally. Depending on the degree and rate of change in the biochemical energetics, it is possible to account for rod and the other more complex shapes of Gram-negative bacteria. Division occurs in Gram-negative organisms by the development of constrictions that progressively invade the cytoplasm. The work to cause these morphological processes must ultimately derive from the biochemical process of the stress-bearing wall formation. A biophysical basis for cell division in these prokaryotic organisms is proposed.

Analysis of temporal-length limitations in XeCl lasers

Experimental observations of the development of constrictions in rare-gas halide laser discharges are reported. The onset of constriction is related to the premature termination of both spontaneous emission and laser pulses in a discharge-excited XeCl laser. A mechanism is proposed to account for the onset of constriction in this laser which may be more generally applicable to other discharge-excited devices.

Constrictive pericarditis following Coxsackie virus infection.

Infection with Coxsackie B₂ virus is described in a 49-year-old farmer in whom myopericarditis and pneumonitis was followed over a period of 10 months by constrictive pericarditis. The differentiation between restrictive cardiomyopathy and constrictive pericarditis was not achieved without exploratory thoracotomy. The adherent pericardium was successfully excised with complete relief. The literature is reviewed and it is suggested that the development of constriction following Coxsackie pericarditis must be considered at subsequent examinations of the patient.

GROWTH AND DEVELOPMENT OF MYCORRHIZAE OF SUGAR MAPLE (ACER SACCHARUM MARSH.)

Beaded rootlet growth in Acer saccharum is thought to be caused by intermittent growth due to alternately favorable and unfavorable moisture conditions during the season rather than by mycorrhizal infection. Both beaded and nonbeaded rootlets are mycorrhizal-infected, and rootlets growing in the deeper soil levels where moisture conditions do not fluctuate rapidly are nonbeaded. Differences found in the activity of rootlets growing in hummocks and depressions appeared to be related to soil moisture conditions found there. This paper describes (a) the anatomy of metacutinized root tips during dry soil conditions, and the relationship of this condition to the development of constrictions between beads; (b) the extrastelar anatomical characteristics of beaded and nonbeaded rootlets; (c) the morphology of the mycorrhizal fungus in its relationship to rootlet anatomy; (d) the extramatrical mycelium of the mycorrhizal fungus found in the soil of the rooting zone (the extramatrical mycelium is thought to arise from fungal hyphae and vesicles produced in live rootlets which are released to the soil from disintegrating rootlet cortical tissue); and (e) an hypothesis regarding the life history of this type of vesicular–arbuscular mycorrhizal fungus.