Search PubMed⌕ Search

Biomedical subjects

C V Reddy

Publications and source records attributed to C V Reddy.

At least 37 records · Page 2Linked to original sources
PubMed1993

Effect of vitamin A deficiency on the adhesion of rat corneal epithelium and the basement membrane complex.

PURPOSE: To understand the underlying mechanisms responsible for the easy removal and sloughing of corneal epithelium in vitamin A deficiency. METHODS: An animal model of vitamin A deficiency, the vitamin A-deficient rat (A-rat), transmission electron microscopy, computer-assisted morphometric analysis and indirect immunofluorescence were used to study the adhesion of rat corneal epithelium to its basement membrane with emphasis on structure and molecular composition of the anchoring structures such as the hemidesmosome and bullous pemphigoid antigen. RESULTS: Transmission electron microscopy resolved numerous microseparations of the basal epithelial cell membrane from the basement membrane with intervening segmental basement membrane duplications and electron dense deposits. Morphometric analysis disclosed a statistically significant reduction in the frequency and size of hemidesmosomes. Four weeks after supplementing the diet with retinyl acetate (700 micrograms/week), significant reversal of these same structural abnormalities could be detected. Immunofluorescence staining for bullous pemphigoid antigen, a component of the adhesion complex, showed intense staining of the basal epithelial cytoplasm but weak and discontinuous staining of the basement membrane. Weak staining for laminin was also evident in A- corneas. In contrast, normal corneas displayed no cytoplasmic staining for bullous pemphigoid antigen and intense staining of the basement membrane for bullous pemphigoid antigen and laminin. CONCLUSIONS: The authors propose that structural abnormalities of the epithelial basement membrane complex are responsible for the observed loose epithelial adhesion and sloughing, as well as other known abnormalities of healing in the vitamin A-deficient rat cornea.

Animals↗
PubMed1992

Internal mammary artery angiography should be a routine component of diagnostic coronary angiography.

Left internal mammary artery (LIMA) angiography was performed with diagnostic coronary angiography in 130 cases for which the coronary findings made use of the LIMA as a bypass graft a consideration. In 98% of the cases the approach to LIMA angiography was femoral with a 5F LIMA catheter first directed into the proximal subclavian and then advanced over a guidewire placed into the distal subclavian well beyond the origin of the LIMA. After withdrawing the wire the catheter was brought proximally to selectively cannulate and visualize the LIMA with nonionic contrast media. The only complication was a single transient occipital visual field loss. LIMA caliber too narrow to permit use as a graft was found twice, LIMA occlusion unrelated to prior surgery was found once, and LIMA occlusion related to prior surgery was found twice. Subclavian and/or vertebral stenosis was present five times. Large proximal branches of the LIMA best identified prior to surgery were present 12 times. Based on this experience, LIMA angiography 1) can be performed safely with a high degree of success, 2) demonstrates significant findings in 15% of cases, and 3) should therefore be performed whenever coronary angiographic findings make it appropriate to consider LIMA to coronary artery bypass grafting.

Adult↗
PubMed1991

Effect of fibronectin on corneal epithelial wound healing in the vitamin A-deficient rat.

The authors investigated the in vitro and in vivo effects of fibronectin (Fn) on the migration of corneal epithelium of vitamin A-deficient (A-) and pair-fed control (A+) rats. Groups treated with 50 micrograms/ml Fn showed accelerated healing of epithelium in vitro (P less than 0.05) compared with control groups of A- and A+ rats. However, when 100 micrograms/ml Fn eye drops were administered 14 times over 20 hr, they had no significant effect on A+ rats in vivo, but increased the healing in A- rats (P less than 0.05). In this model, Fn promoted the healing of corneal epithelium under A- conditions where decreased endogenous Fn is seen, whereas A+ corneas in vivo, which have sufficient Fn over the wound surface, did not benefit from topical Fn administration.

Administration, Topical↗
PubMed1990

Complete heart block complicating retrograde left heart catheterization.

Three cases of complete heart block complicating retrograde left heart catheterization are presented. In two of the three cases, electrophysiologic study documented block below the AV (atrial ventricular) node. In the third recurrent complete heart block was fatal. It appears that complete heart block complicating retrograde left sided cardiac catheterization is not simply a pericatheterization event; rather, it appears that there is high risk of recurrent complete heart block and that electrophysiologic study is mandatory.

Aged↗
PubMed1989

Dynamics of corneal epithelial healing after an alkali burn. A statistical analysis.

A precise definition of epithelial healing kinetics following chemical injury is necessary to aid the investigation of control mechanisms, potential therapeutic intervention and ophthalmic drug toxicity. Wound healing was studied photographically at frequent intervals in rabbits following 1N or 4N alkali burns. Planar wound areas were determined by computerized planimetry and transformed mathematically to curved surface data. The decrease in equivalent wound radius with time was computer-modelled using two linear and three nonlinear regressions. A periodic function was also investigated. Serial photographs showed that intermittent attrition of small areas of the migrating wound edge was a common confounding variable. Although excellent coefficients of determination were found for all models, the addition of nonlinear factors gave a small advantage. A mean lag phase of 3.96 and 6.52 hr occurred after 1N and 4N alkali burns, respectively; wound edge attrition was notably prevalent in early healing. Epithelial healing in the rabbit had a fundamental linear component, with mean epithelial migration rates of 76 and 80 microns/hr after 1N and 4N alkali burns, respectively, and which continued to closure. A quadratic nonlinear component was also suggested. No significant circadian component was detected.

Alkalies↗
PubMed1988

Bilateral coronary thrombosis in the absence of inducible coronary spasm, thrombocytosis, coagulation abnormalities, or angiographic evidence of coronary artery disease: previously undescribed method of myocardial infarction.

A 32-year-old man presented with symptoms and electrocardiographic changes consistent with acute anterolateral myocardial infarction. Selective coronary angiography revealed thromboses in the infarct related artery as well as in the right coronary artery. This case is unique because bilateral in-situ coronary thrombosis producing acute myocardial infarction was documented in the absence of previously proposed mechanisms.

Adult↗
PubMed1985

The radiographic appearance of arterial sheath kinking.

A case of arterial sheath kinking is reported. Radiographically, sheath kinking has some features which mimic sheath fracture. The radiographic appearance of sheath kinking is, however, distinctive and clearly separable from sheath fracture, the hallmark of which is extravasation of contrast at the fracture site.

Angioplasty, Balloon↗
PubMed1985

Changed learning curve for percutaneous transluminal coronary angioplasty. Implication for the future treatment of coronary artery disease.

As with all skilled techniques, there is a learning curve for percutaneous coronary angioplasty. This curve has been well described in the literature and it is generally quoted that an initial success rate of 70 to 75 percent in reaching and crossing lesions is to be expected during the first 20 cases. However, the introduction of the steerable or guidewire-directed dilation catheter has altered the learning curve. After an initial experience of six nonsteerable percutaneous transluminal coronary angioplasty procedures, 20 consecutive steerable percutaneous transluminal coronary angioplasty procedures were performed without a single failure to reach or cross a lesion. These 20 consecutive steerable coronary angioplasty procedures included eight single left anterior descending lesions, two double (lesions located in series) left anterior descending lesions, six single right coronary lesions, one double (lesions located in series) right coronary lesion, and three single circumflex lesions. It is concluded that the introduction of the steerable system for percutaneous transluminal coronary angioplasty has shifted the learning curve, and that skilled and experienced coronary angiographers beginning a coronary angioplasty program can expect an initial success rate in reaching and crossing obstructive coronary lesions far in excess of the figures quoted in the literature. This may have significant implication for the ultimate availability of percutaneous transluminal coronary angioplasty to patients with coronary artery disease.

Adult↗
PubMed1985

Surgical management of synchronous coronary artery disease and multiple aortic stenosis: a case report with brief review of the literature.

One-stage surgery was successfully performed in a 44-year-old hypertensive man with uncontrolled angina, multiple coarctations of the thoracic and abdominal aorta, and a previous subtotal gastrectomy. There was a gradient of 120 mm Hg between the thoracic and abdominal aorta. A graft was placed retroperitoneally from the infrarenal aorta to the ascending aorta and was followed by a coronary artery bypass graft. Twenty-four months postoperatively, the patient was free of angina, and his hypertension was easily controlled.

Journal Article↗
PubMed1984

Coronary artery dissection secondary to coronary arteriography: case report and review.

A case of catheter-induced proximal dissection of an angiographically normal left coronary artery is reported. Dissection was not associated with pressure damping and myocardial ischemia was delayed until 1 hour after dissection occurred. Prompt recognition of this entity is essential as emergency revascularization is the treatment of choice when significant amounts of myocardium are threatened.

Cardiac Catheterization↗
PubMed1984

Nonrandom occurrence of single-vessel coronary artery disease.

The location of obstructive coronary artery lesions in single-vessel disease is nonrandom. The circumflex coronary artery is protected relative to the right coronary artery. This may have important implications regarding the causation of coronary obstructive lesions.

Coronary Angiography↗
PubMed1983

Catheter separation during coronary angiography.

Complete fracture and separation of a right coronary Judkins catheter during coronary angiography is presented. The possible mechanism underlying the separation and retrieval of the catheter fragment is described.

Angiography↗
PubMed1983

Aortico-right ventricular shunt following aortic valve replacement.

A 58-year-old man developed cardiac decompensation following aortic valve replacement as a result of an aortico-right ventricular fistula. Serial hemodynamic and electrocardiographic changes are presented. Attention is drawn to this rare complication as a cause of hemodynamic deterioration following aortic valve surgery.

Aortic Diseases↗