Recent advances in IOL surgery

Tremendous progress is made in recent time in the field of Ophthalmology especially after advent of IOL implantation surgery. Recent advance in anaesthesia/IOL, designs/IOL, quotings/cantering, techniques/advances in operating microscope and advances in suture materials/needles etc. will be discussed.

Immediate free tissue transfer for distal musculoskeletal neoplasms

Sarcomas and other aggressive neoplasms of the extremities present particular challenges for limb salvage when the tumors are located distally in the arms or legs. These tumors require a large area of excision, yet there are no suitable options for local tissue coverage. In the past, amputation was often necessary due to the inability to adequately reconstruct the extremity. We performed immediate free tissue transfers on 10 patients with aggressive tumors in the forearm and lower leg. Eight patients had sarcomas, 1 had a melanoma, and 1 had a recurrent fibromatosis. Seven patients had rectus abdominis flaps, 1 had a latissimus dorsi flap, 1 had a groin flap, and 1 had an osteocutaneous flap from the iliac crest. Three patients had tendon transfers at the time of surgery. Four patients required radiation therapy after resection due to the high-grade nature of their neoplasms. The flaps tolerated the radiation well, with only 1 patient sustaining flap necrosis that required skin grafting. Average follow-up was 28 months. All patients are alive and none had local recurrences of their tumors. All free flaps have survived and remained durable. There have been no late breakdowns of skin grafts, and all tendon transfers have functioned well. Immediate free tissue transfer provides an excellent method of reconstruction for distal tumors of the extremities.

Does coronary endarterectomy adversely affect the results of bypass surgery?

Coronary endarterectomy (TEA) is performed infrequently during coronary artery bypass graft (CABG) surgery due to the impression that it results in higher rates of myocardial infarction (MI), operative mortality (OM), and poor long-term outcome. To assess the effectiveness of TEA, 1,228 patients undergoing isolated CABG between 1982 and 1989 were evaluated. The incidence of OM (3.2%) and MI (6.0%) following TEA was similar to conventional CABG (OM = 3.8%, MI = 5.5%, p = NS). The incidence of low output syndrome (LOS, 15.1%) and intraaortic balloon pump insertion (IABP, 4.5%) following TEA was similar to conventional CABG (LOS = 12.6%, IABP = 6.0%, p = NS). The highest level of the cardiac specific isoenzyme (CK-MB) released following surgery was similar for the TEA group (46 +/- 49) and conventional CABG group (42 +/- 44, p = NS). Ventricular dysfunction, urgent surgery, left main stenosis, advanced age, and reoperative surgery were similar in the TEA and conventional CABG groups. At a mean follow-up of 4.2 years, 65.6% of all TEA patients were free of angina, 44.4% were gainfully employed, and 62% were in New York Heart Association Class I. The incidence of late myocardial infarction was 5.4%. The 5-year actuarial survival was 90%. Patients with double TEA and limited TEA ( < or = 3 cm TEA specimens) tended to have a lower 5-year survival. With strict criteria for selection of TEA patients and with significant technical experience, the short- and long-term results of TEA are comparable to conventional CABG.

The expression of human chorionic gonadotropin/luteinizing hormone receptors in human endometrial and myometrial blood vessels

hCG/human LH (hLH) receptors have recently been found in human endometrial and myometrial cells and uterine vasculature. The present study was undertaken to further corroborate the immunocytochemical evidence for the presence of vascular receptors. Northern blot and in situ hybridization analyses have revealed that human uterus contains a major 4.3-kilobase and a minor 2.6-kilobase hCG/hLH receptor mRNA transcript and that these transcripts are present in part in endometrial and myometrial vascular smooth muscle cells and vascular endothelial cells. Immunoblot and immunocytochemical analyses have revealed that human uterus also contains a single immunoreactive receptor protein, and that this receptor protein in part is present in endometrial and myometrial vascular smooth muscle and vascular endothelium. The expression of receptor mRNA and/or immunoreactive receptor protein was higher in myometrial than in endometrial blood vessels, and higher in vessels of both uterine compartments from the secretory compared to proliferative phase, postmenopause, or pregnancy. The blood vessels in omentum, broad ligament, and parametrium did not immunostain for hCG/hLH receptors. A blood vessel seen traversing through parametrium immunostained for the receptor protein only after it entered the myometrium. The blood vessels in nontarget tissues did not immunostain, whereas those in some target tissues, but not all of them, immunostained for the receptor protein. In summary, the present study demonstrates for the first time that human endometrial and myometrial vascular smooth muscle and endothelium express hCG/hLH receptor mRNA and immunoreactive receptor protein. These findings suggest that hCG/hLH may directly regulate blood flow in human uterus and other target tissues. The reproductive state dependency of uterine vascular receptors suggests that these receptors are probably regulated by other reproductive hormones.

Mitral valve replacement: mechanical versus bioprosthetic valves--a clinical review

A review of the literature was conducted in an attempt to justify the exclusive use of either mechanical or tissue prostheses in the mitral position. In addition, the University of Toronto experience with mitral valve replacement was reviewed, including a five year follow-up from the Toronto General Hospital. Both studies concluded that there was no significant advantage for the use of either type of valve based upon freedom from thromboembolism, freedom from anticoagulant-related hemorrhage and freedom from all valve-related mortality/morbidity. Tissue valves were shown to be significantly poorer substitutes in terms of freedom from primary valve failure (P less than 0.05) and freedom from reoperation due to valve-related complications (P less than 0.07). The clinical results from the Toronto General Hospital correlated with those reported in the literature and suggested the preferential use of mechanical valves during mitral valve replacement based primarily on their durability and a consequent lesser need for reoperation.

The galactose-binding sites of the cytotoxic lectin ricin can be chemically blocked in high yield with reactive ligands prepared by chemical modification of glycopeptides containing triantennary N-linked oligosaccharides

A glycopeptide containing a triantennary N-linked oligosaccharide from fetuin was modified by a series of chemical and enzymic reactions to afford a reagent that contained a terminal residue of 6-(N-methylamino)-6-deoxy-D-galactose on one branch of the triantennary structure and terminal galactose residues on the other two branches. Binding assays and gel filtration experiments showed that this modified glycopeptide could bind to the sugar-binding sites of ricin. The ligand was activated at the 6-(N-methylamino)-6-deoxy-D-galactose residue by reaction with cyanuric chloride. The resulting dichlorotriazine derivative of the ligand reacts with ricin, forming a stable covalent linkage. The reaction was confined to the B-chain and was inhibited by lactose. Bovine serum albumin and ovalbumin were not modified by the activated ligand under similar conditions, and we conclude, therefore, that the reaction of the ligand with ricin B-chain was dependent upon specific binding to sugar-binding sites. Ricin that had its galactose-binding sites blocked by the covalent reaction with the activated ligand was purified by affinity chromatography. The major species in this fraction was found to contain 2 covalently linked ligands per ricin B-chain, while a minor species contained 3 ligands per B-chain. The cytotoxicity of blocked ricin was at least 1000-fold less than that of native ricin for cultured cells in vitro, even though the activity of the A-chain in a cell-free system was equal to that from native ricin. Modified ricin that contained only 1 covalently linked ligand was also purified. This fraction retained an ability to bind to galactose affinity columns, although with a lower affinity than ricin, and was only 5- to 20-fold less cytotoxic than native ricin.

Analysis of human chromosome 21: correlation of physical and cytogenetic maps; gene and CpG island distributions

Human chromosome 21 has been analyzed by pulsed-field gel electrophoresis using somatic cell hybrids containing limited regions of the chromosome and greater than 60 unique sequence probes. Thirty-three independent NotI fragments have been identified, totalling 43 million bp. This must account for essentially the entire long arm, and therefore gaps remaining in the map must be small. The extent of the pulsed-field map has allowed the direct correlation of the physical map with the cytogenetic map: translocation breakpoints can be unambiguously positioned along the long arm and the distances between them measured in base pairs. Three breakpoints have been identified, providing physical confirmation of cytogenetic landmarks. Information on sequence organization has been obtained: (i) 60% of the unique sequence probes are located within 11 physical linkage groups which can be contained in only 20% of the long arm; (ii) 9/21 genes are clustered within 4%; (iii) translocation breakpoints appear to occur within CpG island regions, making their identification difficult by pulsed-field techniques. This analysis contributes to the human genome mapping effort, and provides information to guide the rapid investigation of the biology of chromosome 21.

Conjunctival impression cytology for assessment of vitamin A status

Ocular signs and serum vitamin A concentrations are commonly used for the diagnosis of vitamin A deficiency. Recently, impression cytology was suggested as a method for early detection of this condition. A clinical trial was conducted to compare the results of impression cytology with the other two indicators of vitamin A status. A total of 246 children aged 1-10 y were investigated. About 25% of the children with normal eyes showed abnormal cytology. Their mean vitamin A concentrations were significantly lower compared with those with normal cytology, which suggests that abnormal cytology reflects subclinical deficiency. After treatment with vitamin A, most of the children who had abnormal cytology at baseline examination showed improvement. These observations suggest that abnormal cytology is specific to vitamin A deficiency. Impression cytology is a relatively simple technique and can be used for assessing the magnitude of the problem, especially in communities where the prevalence of clinical disease is low.

Acetylsalicylic acid dose fails to affect energy intake of osteoarthritic elderly

The objective of the study was to determine the effect on energy intake and appetite of acetylsalicylic acid (ASA), commonly used by the elderly to treat arthritis. In a double blind cross-over study, 23 free-living osteoarthritic patients 60 years of age or older were treated for two-weeks intervals with a mean daily ASA intake of 2.44 and 1.29 grams, respectively. Twenty healthy persons similar in age, taking no medication, and matched in sociocultural characteristics were included as a control group. Appetite was measured directly, using a visual analogue scale, and indirectly by calculating energy intake from three-day food records. Varying the dose of ASA was without effect on appetite and food energy intake; however, as appetite was rated lower by the medicated osteoarthritic than by the healthy group, although the energy intakes were not significantly different, the former should be considered as potentially at nutritional risk.

Diet, mortality and life expectancy: a cross national analysis

"There are numerous reasons why mortality and life expectancy vary between countries. Epidemiological studies seem to indicate that dietary variations may be among them. A sample of 51 countries studied with data from the International Comparisons Project and other sources, shows that after controlling for nutrient intake, consumption of medical goods and services, income distribution, weather, and literacy, countries with more meat and poultry in their diet have lower life expectancies after age five. The results for infant mortality and child death between one and five indicate that a more animal-intensive diet may be actually beneficial, especially if fish consumption is increased and meat and poultry consumption reduced."

Various manifestations of hyperthyroidism in an ambulatory clinic: case studies

This study reviews five cases of women with hyperthyroidism, three black women and two Hispanic women. Initially, two patients presented with voice changes, weight loss, and increased appetite. Only two patients presented with classical symptoms of hyperthyroidism. Examination showed all patients had diffusely enlarged thyroids and exaggerated reflexes. Two patients showed Graves' opthalmopathy.These cases document the variety of presentations of hyperthyroidism. Hence, a high index of suspicion must exist for this disease, even in the absence of a number of the classical manifestations of hyperthyroidism. When patients present to primary care centers with a constellation of symptoms, an examination of the thyroid gland is essential.

The pathology and pathogenesis of Salmonella stanley infection in experimental chicks

Experimental infection with Salmonella stanley was produced by oral, intravenous and intramuscular routes in day-old chicks. The earliest evidence of the presence of the organisms was in duodenal mucosa six hours after oral infection. Following oral infection the organisms were detected in the duodenum from six hours to five days, in the caecum from 12 hours to nine days, liver, spleen and blood from 24 hours to seven days. The resistance to infection was found to be significant after 10 days old, but not up to six days old. The work confirmed that the survival time of birds given S stanley by the intravenous or intramuscular routes was inversely proportional to the dose up to a maximum beyond which the survival time was not further decreased by dose increase. The presence of S stanley in tissues and blood was detected by isolation and by the fluorescent antibody technique.

Conjunctival goblet cells and mitotic rate in children with retinol deficiency and measles

To study the effect of retinol deficiency and measles on the conjunctival epithelium, we determined the epithelial mitotic rate (MR) and goblet cell frequency (GCF) in conjunctival biopsy specimens from preschool children in Hyderabad, India. We studied three groups of children: normal appearing, clinically retinol deficient (defined by the presence of superficial fine punctate keratitis), and clinically retinol deficient with measles. The last group was subdivided into those with low serum retinol levels (less than or equal to 20 micrograms/dL [less than or equal to mumol/L]) and those with normal serum retinol levels (greater than 20 micrograms/dL [greater than 0.70 mumol/L]). In the control group of seven normal-appearing children with a mean age of 4.6 years, the mean MR was 1.3% +/- 0.4%, and the mean GCF was 8.0% +/- 3.6% of the basal epithelial cells. In seven children with clinical retinol deficiency, the mean MR was 15.4% +/- 1.2%, and the mean GCF was 1.0% +/- 0.5%, values significantly different from normal ones. Among 11 children with clinical retinol deficiency, measles, and low serum retinol levels, the mean MR was 9.0% +/- 1.9%, and the mean GCF was 3.1% +/- 1.1%, values not statistically different from those in children with clinical retinol deficiency alone. Five children with clinical retinol deficiency, measles, and normal serum retinol levels had a mean MR of 10.2% +/- 3.7% and a mean GCF of 1.9% +/- 1.7%, values similar to those in the other disease groups. This indicates that retinol deficiency sufficient to cause clinical signs without subepithelial scarring or keratinization is associated with hyperproliferation of the conjunctiva whether or not there is a superimposed measles infection.

Diagnosis of hyperthyroidism in patients with thyroiditis: a case study

A diagnosis of subacute thyroiditis can be difficult to make in the early stages of disease, especially when patients present with symptoms of a hyperthyroid state that are nonspecific and mild. Using three case histories, the authors demonstrate how an early diagnosis of thyroiditis was made in these patients.

Relationship between measles, malnutrition, and blindness: a prospective study in Indian children

A prospective study was conducted in slum children to determine the incidence of post-measles corneal disease and to clarify its relationship with nutritional status. A total of 318 cases of measles were identified over a period of 15 mo; maximum incidence was observed for children between 1-2 yr. Most of the children showed weight loss and serum proteins decrease during the acute stage of measles. Corneal lesions were observed in 3% of the children, and the lesions responded well to treatment. Serum vitamin A and RBP levels were significantly depressed during the acute stage of measles but were restored to normal 8 wk after recovery. There were no significant differences in the serum levels for those with and without eye lesions, which suggests that these lesions may not be mediated simply through the effect of infection on serum concentration of vitamin A.

Syndrome of galactorrhea, amenorrhea, and obesity as possible indicators of prolactinoma: a case study approach

Four female patients were found to have microadenomas and high prolactin levels, but the symptoms of the syndrome varied among the patients. Three of four patients had overt galactorrhea, obesity, and amenorrhea. One patient was postmenopausal, and another showed menstrual irregularities. Two patients sought medical attention for headaches, and one for visual disturbances. Two patients previously had used psychotropic drugs, and two patients used birth control pills. When tested, all patients had high serum prolactin levels, abnormal sellar tomograms, and the presence of microadenoma of the pituitary was confirmed by computerized tomography.Because of the high incidence of pituitary tumor among these four patients, this study suggests that a complete workup should be done for patients having galactorrhea, amenorrhea, and obesity as a syndrome or as separate entities.

MRI of joint fluid in the normal and ischemic hip

MR images in 36 hips with documented avascular necrosis and 80 hips without evidence of joint disease were studied to determine the amount and appearance of fluid in the joint. All MRI examinations were done on a 1.5-T machine and included coronal images made with relative T2 weighting (repetition times = 2000-2500 msec, echo delays = 60-100 msec). The amount of joint fluid, which had an intense signal higher than fat, was graded from 0 to 3 and analyzed with respect to the patient's age and radiographic stage of avascular necrosis. Joint fluid was seen in 84% of presumed normal hips. Only four (5%) of 80 had enough fluid to surround the femoral neck (grade 2), and none had sufficient fluid to distend the joint capsule (grade 3). In comparison, 21 (58%) of 36 hips with avascular necrosis had grade-2 or grade-3 effusions (p less than 0.005), and some fluid was seen in all. Grade-3 effusions were seen in seven (50%) of 14 hips with flattening of the femoral head, compared with only one (5%) of 20 in which the femoral contour was normal. It is concluded that small amounts of fluid are present in both normal hips and those with avascular necrosis. In avascular necrosis, increased joint fluid may be present before radiographic abnormalities occur, but it is greatest after there is flattening of the femoral head. MRI is a highly sensitive method for detecting fluid in the hip joint.

Pathogenesis of corneal lesions in measles

The mechanism of pathogenesis underlying the development of corneal lesions in measles was investigated in 125 children suffering from measles and 66 age- and sex-matched healthy controls. Forty age-matched children with bronchopneumonia were investigated on similar lines to delineate the role played by vitamin A and measles individually in the development of corneal lesions. The results indicate that the pathogenesis of corneal lesions in measles is indeed multifactorial. Vitamin A deficiency alone or measles keratitis per se may not explain the mechanism completely. The immunosuppression induced by the local proliferation of the measles virus in the eye might trigger the invasion of pathogenic microbes which damage the cornea. The structural integrity of the cornea is already compromised by vitamin A deficiency and lesions of measles keratitis.

Effect of dopamine and dopamine-receptor blockade on in vitro renin release, tissue renin content and tissue cyclic AMP content in the rat

This study evaluated the in vitro renin release, tissue cyclic AMP content (TcAMPc), and tissue renin content (TRC) changes with time, in response to administration of dopamine (DOP) and of the dopamine-receptor blocking agent pimozide (PIM) to renal cortical slices from sodium deficient (SD) rats. Addition of 10(-3)M DOP to the slice preparation resulted in a gradual stimulation of RR with time, which was significantly different from that seen in control samples after 60 min of incubation. In contrast, TcAMPc of the DOP-treated samples was significantly greater than that of controls after 5 min of incubation. At 60 min, mean TRC of DOP-treated samples was greater than that of controls but not significantly. Two PIM doses (10(-8)M and 10(-6)M, whether added alone or together with 10(-3)M DOP to the cortical slice system, significantly increased RR in each instance while simultaneously depressing TcAMP content markedly below that of unstimulated controls at all incubation times examined. Mean TRC of pimozide-treated samples was also lower than that of controls by 60 min. These in vitro data in the SD rat suggest that: 1) stimulation of renin release by DOP is time-dependent and is mediated by a TcAMP-generating mechanism, and 2) the increase in renin release by PIM administration appears to involve pharmacological inactivation of TcAMP-generating pathways and disruption of membrane permeability, leading to uncontrolled RR.

Factors affecting neurobehavioral responses of preterm infants at term conceptional age

A revised Prechtl Neurological Examination was administered to 510 singleton infants at term conceptional age to assess the influence of gestational age, race, and sex on neurobehavioral responses in a "typical" newborn population. The infants were born at 1 of 5 centers and were subjects of the NIH Collaborative Study on Antenatal Steroid Therapy. Of these babies, 392 were born at less than 37 weeks gestational age, whereas 118 infants were born at greater than or equal to 37 weeks. Of a total of 50 items of interest, 12 differed significantly based on race, 14 items differed in terms of gestational age at birth, and 5 items were influenced by the sex of the baby. These data suggest that singleton preterm infants born at differing gestational ages should not be considered to comprise a homogeneous sample. Further, caution should be exercised when considering babies of heterogeneous race groupings, and the babies' sex has minimal impact on neurobehavioral responses at term conceptional age.