Processing of Aluminium-Silicon Alloy with Metal Carbide as Reinforcement through Powder-Based Additive Manufacturing: A Critical Study.

Powder-based additive manufacturing (PAM) is a potential fabrication approach in advancing state-of-the-art research to produce intricate components with high precision and accuracy in near-net form. In PAM, the raw materials are used in powder form, deposited on the surface layer by layer, and fused to produce the final product. PAM composite fabrication for biomedical implants, aircraft structure panels, and automotive brake rotary components is gaining popularity. In PAM composite fabrication, the aluminium cast alloy is widely preferred as a metal matrix for its unique properties, and different reinforcements are employed in the form of oxides, carbides, and nitrides. However, for enhancing the mechanical properties, the carbide form is predominantly considered. This comprehensive study focuses on contemporary research and reveals the effect of metal carbide's (MCs) addition to the aluminium matrix processed through various PAM processes, challenges involved, and potential scopes to advance the research.

Anti-glomerular Basement Membrane Disease: A Rare Case Report of Changing Clinical Phenotype and Atypicalities.

A man in his late 20s, a smoker, presented with nephrotic-range proteinuria and mild renal failure. He had no macroscopic hematuria or decreased urine output. Kidney biopsy was done which revealed a surprising diagnosis of anti-glomerular basement membrane (anti-GBM) disease. He was started on intravenous methylprednisolone, plasma exchanges, and cyclophosphamide. His anti-GBM antibody was, however, weak positive. After five sessions of plasma exchange, he was discharged with a negative anti-GBM antibody. The patient defaulted drugs and presented with rapidly progressive renal failure and hemoptysis after 1½ months. The patient was started on intravenous methylprednisolone, hemodialysis, plasma exchanges, and cyclophosphamide. Repeat biopsy after stabilization was suggestive of anti-GBM disease with fibrocellular crescents. Anti-GBM antibody was negative. Although the patient presented with an estimated glomerular filtration rate of 10 mL/min/1.73 m2 and fibrocellular crescents, the patient improved with treatment and was discharged with a serum creatinine of 2.2 mg/dL. This patient had two presentations: one with nephrotic-range proteinuria and mild renal failure, revealing anti-GBM disease on biopsy, and the second with rapidly progressing renal failure which improved with treatment. There were many atypical features in his presentation. Nonabstinence from smoking might be a triggering factor for the second episode. The pathological antibodies may be against a nonconventional epitope or poorly complement fixing, resulting in negative anti-GBM antibody and good recovery in spite of severe renal failure.

Expression of Survivin in Oral Potentially Malignant Disorders: An Immunohistochemical Study.

AIM: The aim of this study was to compare the immunohistochemical expression of survivin in oral potentially malignant disorders (OPMDs) and evaluate its prognostic significance among oral leukoplakia (OL), oral submucous fibrosis (OSMF), and oral lichen planus (OLP). MATERIALS AND METHODS: The study material consisted of 60 formalin-fixed paraffin-embedded tissue samples: 15 cases each of OL, OSMF, OLP, and normal oral mucosal epithelium as control. Survivin expression was analyzed immunohistochemically, and data analysis was accomplished using Statistical Package for Social Sciences, version 22.0 (SPSS Inc., Chicago, IL). Fisher's chi-square test was opted to compare the study groups. RESULTS: Survivin was expressed in all the OPMDs including OL, OSMF, and OLP, but was absent in normal oral tissue samples. Higher immunoreactivity and survivin staining was observed in OLP compared to OL and OSMF whereas OL showed a significant difference in the distribution of survivin immunoexpression against OLP. An increased nuclear expression of survivin along with distribution in the basal and parabasal layers was evident in all OPMDs. CONCLUSION: Survivin was expressed more in OLP in comparison to OSMF and OLP, indicating unfavorable prognosis. OL showed increased expression in comparison to OSMF, showing unfavorable prognosis. On the basis of this study, it was concluded that survivin may be used as an important diagnostic and prognostic marker for OPMDs.

Prediction of tubulo-interstitial injury by Doppler ultrasound in glomerular diseases: value of resistive and atrophic indices.

BACKGROUND: Doppler ultrasound is increasingly used in Nephrology for diagnosis of renovascular hypertension and evaluation of allograft dysfunction. However, its utility in glomerular disease remains controversial. OBJECTIVES: Using Doppler Ultrasound, we prospectively tested the role of resistive and atrophic indices in predicting tubulointerstitial lesions in patients with glomerular disease as demonstrated by renal biopsy. METHODS: Seventy one patients with primary or secondary glomerular diseases were examined by Doppler ultrasonography immediately before renalbiopsy. The resistive and atrophic indices (RI & AI) were calculated and compared with histologic changes in biopsy specimen. RESULTS: Receiver Operator Characteristics analysis showed RI of 0.60 as an optimal value for discriminating tubulointerstitial changes with sensitivity of 82.7% and specificity of 92%. An AI of 0.65 was shown to be optimal for discriminating tubulointerstitial injury with sensitivity of 69.2% and specificity of 85%. The combination of the two indices had not been found to be superior to either index alone. There was a significant correlation between atrophic and resistive indices. (r=0.358, p< 0.01). It was observed that older age, smoking, elevated AI and RI, low GFR, high serum cholesterol and Hypertension were found to be significantly associated with the presence of tubulointerstitial injury in the univariate analysis whereas only elevated AI and RI were found to predict tubulointerstitial injury in multivariate analysis. CONCLUSION: Measurement of RI by Doppler ultrasound can be considered as a supplementary diagnostic tool in glomerular diseases to predict the severity of tubulointerstitial injury.

Nephrocalcinosis in siblings--familial hypomagnesemia, hypercalciuria with nephrocalcinosis (FHHNC syndrome).

Familial Hypomagnesemia, Hypercalciuria with Nephrocalcinosis is a rare autosomal recessive inherited disease associated with renal failure. Two girls born of consanguineous parentage aged 16 and 17 presented to us with renal failure, nephrocalcinosis and bone deformities. On evaluation they were found to have hypomagnesemia, hypercalciuria, increased fractional excretion of magnesium, hypocitraturia, renal failure and elevated PTH. Their parental screening was normal. There were no extra-renal features in them. One sibling had nephrolithiasis and the stone analysis revealed calcium phosphate stones. Both were treated with sodium bicarbonate, thiazides, calcitriol and calcium carbonate. They did not require dialysis during hospital stay. Both of them were treated conservatively. They are on regular outpatient follow up. The primary defect in this syndrome is impaired paracellular reabsorption of magnesium and calcium in the medullary thick ascending limb. Mutations in the PCLN-1gene which encodes for the tight junction protein paracellin -1 is identified as the underlying genetic defect. Ocular abnormalities and deafness are the commonly reported associations. End stage renal failure usually occurs in second to third decade. Renal transplantation is the definite treatment.

Epidemiologic trend changes in acute renal failure--a tertiary center experience from South India.

BACKGROUND: There are little data on the incidence of acute renal failure (ARF) from India due to the absence of central registry. The etiology, course, and outcome of ARF differ in various parts of India. Significant trend changes were reported even within a same center over a period of time. AIM: To find out the epidemiologic trend changes in ARF patients, the authors compared the profile of patients admitted by the Department of Nephrology from 1995-2004 with previously published data from 1987-1991. METHODS: Data collected from case records of patients admitted with ARF were systemically analyzed for age, gender, etiology, course, and outcome. A total of 32 variables were collected per person retrospectively. The chi-square test, Fisher's exact test, and student t-test were used as tests of significance (p<0.05 was taken as statistically significant). RESULTS: A total of 1112 patients were diagnosed to have ARF from 1995-2004. The mean age was 37.08 +/- 3.4 yrs. There were 669 (60.1%) males. Medical, obstetric, and surgical causes accounted for 87.6, 8.9, and 3.4 percent of ARF, respectively. Among the medical causes of ARF, acute diarrheal disease was the most common. Other causes of medical ARF included drugs, glomerulonephritis, sepsis, snake bite, leptospirosis, malaria, and copper sulphate, which accounted for 13.4, 9.3, 8.8, 7.8, 7.5, 4.4, and 4.3 percent, respectively. In comparison with the data from 1987-1991, medical ARF remained the most common cause of ARF, though without any statistical significance (87.6 percent vs 89.5 percent, p>0.32). Though surgical ARF had more than doubled from 1.5 percent from 1987-1991 to 3.4 percent (p<0.01) during the present study, it is much less when compared to similar studies in the literature. Obstetric renal failure more or less remained the same (8.9 percent vs 9 percent, p>0.4). A statistically significant decline was noted in overall as well as individual group mortality. The overall mortality declined from 26.4 percent to 19.6 percent (p<0.02). Regarding the outcome of ARF, 611 patients (54.94 percent) showed a total recovery, a partial recovery was noted in 192 patients (17.26 percent), and 91 patients (8.18 percent) had persistent dialysis-dependent renal failure. The factors noted to occur more frequently in the deceased were high entry serum creatinine (>440 micromol), jaundice, sepsis, oliguria, anemia, hypoalbuminemia, and hospital-acquired ARF. The overall requirement of dialysis was 69.0 percent. Hemodialysis was the most common modality of renal replacement therapy. CONCLUSIONS: ARF in South India differs in some important aspects when compared with data from other parts of the country. Significant trend changes were noted with time even within our center. Acute diarrheal disease was the most common cause of ARF. Leptospiral ARF was on the decline, and drugs, sepsis, and malaria were the emerging ARF causes. The incidence of surgical ARF was on the rise. Despite improvements in antenatal care, obstetric renal failure remained a significant cause of ARF. Hemodialysis became the preferred mode of renal replacement therapy.

Hyperglycemic hyperosmolar nonketotic syndrome.

Hyperglycemic hyperosmolar nonketotic syndrome (HHNS) was infrequently diagnosed till recently. Now it is being diagnosed with increasing frequency in obese children with type 2 diabetes mellitus (T2 DM) and its incidence is likely to go up, given global increase in incidence of childhood obesity, increased insulin resistance, and T2 DM. The syndrome is characterized by severe hyperglycemia, a marked increase in serum osmolality and dehydration without accumulation of beta -hydroxybutyric or acetoacetic ketoacids. Significant ketogenesis is restrained by the ability of the pancreas to secrete small amount of insulin. Prolonged phase of osmotic diuresis leads to severe depletion of body water, which excees that of sodium, resulting in hypertonic dehydration. These children, usually obese adolescents with T2 DM, present with signs of severe dehydration and depressed mental status but continue to have increased rather than decreased urine output and are at increased risk of developing rhabdomyolysis and malignant hyperthermia. Emergency treatment is directed at restoration of the intravascular volume, followed by correction of deficits of fluid and electrolyte (Na+, K+, Ca++, Mg++, PO4++), hyperglycemia and serum hyperosmolarity, and a thorough search for conditions that may lead to this metabolic decompensation and their treatment. Use of iso-osomolar isotonic fluid (0.9% saline) until hemodynamic stabilization initially, followed by 0.45% saline with insulin infusion at the rate of 0.1 units/kg/hour, addition of 5% dextrose in fluids and reduction of insulin infusion once the blood glucose is 250 to 300 mg/dl is generally recommended. However, evidence-based guidelines about composition and tonicity of fluids and electrolyte solutions for early resuscitation and rehydration, the rate of infusion-rapid vs slow, and insulin dose-low vs normal, in treatment of HHNS in children are awaited. Careful monitoring of glucose levels and ensuring adequate hydration in patients 'at risk' of HHNS, including those receiving medications that interfere with the secretion or effectiveness of insulin should decrease the risk of HHNS.

Study of the autoantibody profile after the acute phase of Kawasaki disease in a cohort of children from North India.

A study of organ-specific and organ-nonspecific autoantibodies was carried out in 21 children being followed up after a diagnosis of Kawasaki disease at a tertiary care center of North India. Anti-nuclear antibodies were detected in 9.5% patients while anti-thyroid microsomal antibodies were detected in 23.9% patients. Other autoantibodies (e.g. anti-parietal cell antibody, anti-liver kidney microsomal antibody anti-neutrophil cytoplasmic antibody, anti-mitochondrial antibody and anti-smooth muscle antibody) were not detected in any of our patients. Children with Kawasaki disease need to be monitored for the development of autoantibodies during follow-up.

Hyperglycemic hyperosmolar nonketotic syndrome in a child with acute lymphoblastic leukemia undergoing induction chemotherapy: case report.

Hyperglycemic hyperosmolar nonketotic syndrome, a life-threatening complication commonly associated with uncontrolled type 2 diabetes mellitus in adults, is characterized by severe hyperglycemia, a marked increase in serum osmolality, and clinical evidence of dehydration without the accumulation of beta-hydroxybutyric or acetoacetic ketoacids. There is a variable alteration in sensorium. The syndrome has been rarely reported in children with leukemia undergoing induction therapy. The authors' aim is to sensitize physicians to this life-threatening illness, which can be treated effectively if diagnosed early.

Molecular structure and vibrational raman and infrared spectra of bromochlorofluoromethane and its silicon and germanium analogs: quantum-mechanical DFT and MP2 calculations.

DFT(B3LYP) and MP2 calculations with the 6-311G(2d, 2p)-type basis set have been carried out for the prediction of molecular parameters (bond distances, bond angles, rotational constants, and dipole moments) and vibrational Raman and infrared spectra (harmonic wavenumbers, absolute intensities, Raman scattering activities, and depolarization ratios) of bromochlorofluoromethane (HCBrCIF) and its silicon and germanium analogs (HSiBrClF and HGeBrCIF). The predicted geometry and vibrational Raman and infrared spectra of HCBrClF agree well with the available experimental data for this molecule and their deuterated derivatives. This agreement allows one to believe that the predicted molecular parameters and vibrational spectra of HSiBrClF, HGeBrClF, and their deuterated derivatives will guide their future experimental studies.

A study of ocular morbidity among elderly population in a rural area of central India.

A cross-sectional study was conducted in five randomly selected villages in Wardha district of Maharashtra state to study the magnitude and factors related to the prevalence of ocular diseases among the elderly population. A total of 903 persons above 50 years were screened. The prevalence of low vision was 32% while that of blindness was 12.2%. Ocular morbidity rate was 1.21 lesions per elderly person and it increased significantly with increasing age (p < 0.001). Ocular diseases were found to be more prevalent among males, low socio-economic status group and landless labourers (p < 0.001). There was a high prevalence of refractive errors (40.8%), cataract (40.4%), aphakia (11.1%) followed by pterygium (5.2%), glaucoma (3.1%) and corneal opacities (3%). Prevalence of diseases of the lens and iris increased significantly with increasing age (p < 0.001). There is a need to evolve strategies for reducing the burden of ocular diseases and improve geriatric eye health under the existing infrastructure of health care delivery in our country.

Epidemiological aspects of visual impairment above 50 years in a rural area.

A cross-sectional survey was conducted in 5 villages in central India to find out the extent, causes and epidemiological factors for visual impairment among 903 individuals aged above 50 years; 44.3% of them were visually impaired (29.4% with low vision and 14.9% blind). Age-specific visual impairment increased at a rate of 13.2% with each decade of advancing age. Landless labourers suffered more from visual impairment than other occupational groups (p < 0.05). Socioeconomic and literacy status of the population did not significantly influence the prevalence of visual impairment. Major causes of visual impairment were cataract (48.5%), refractive errors (24.5%), age-related macular degeneration (10%), glaucoma (6.8%), and others (10.2%). In view of the high prevalence of visual impairment among the elderly individuals, it is necessary to intensify our efforts in motivating them for early detection and treatment.

End-tidal CO2 monitoring in mitral stenosis patients undergoing closed mitral commissurotomy.

Arterial to end-tidal carbon dioxide difference (P(a-E')CO2) was recorded in 20 mitral stenosis patients (group A) for closed mitral commissurotomy and 20 healthy individuals (group B) for elective limb surgery. Mitral stenosis patients showed a greater difference than group B patients. Repeated measurements of P(a-E')CO2 in mitral stenosis patients at various stages of closed mitral commissurotomy not only showed a mean increase from before thoracotomy but there was also no correlation between P(a-E')CO2 before thoracotomy with that after thoracotomy, after commissurotomy or after chest closure. This indicated that end-tidal CO2 monitoring was unsuitable to measure adequacy of ventilation during closed mitral commissurotomy.

Synthesis and biological evaluation of a tetrahydroisoquinoline derivative possessing selective beta2-adrenergic agonist activity.

This paper reports the synthesis of 4-(3,4,5-trimethoxybenzyl)-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (2) and 2-(3,4-dihydroxyphenyl)-3-(3,4,5-trimethoxyphenyl)propylamine (3). The biological activity of these agents relative to that of trimetoquinol (1) in guinea pig atria and guinea pig trachea is reported. The relative activities in relaxation of guinea pig trachea is 1 greater than 2 greater than 3 while in the chronotropic response in guinea pig atria the relative order of activity is 1 greater than 3 greater than 2.