Bifunctional g-C3N4/carbon nanotubes/WO3 ternary nanohybrids for photocatalytic energy and environmental applications

Ternary nanohybrids based on mesoporous graphitic carbon nitride (g-C3N4) were synthesized and presented for developing stable and efficient Hydrogen (H2) production system. Based on photocatalytic activity, optimization was performed in three different stages to develop carbon nanotubes (CNTs) and WO3 loaded g-C3N4 (CWG-3). Initially, the effect of exfoliation was investigated, and a maximum specific surface area of 100.77 m2/g was achieved. 2D-2D interface between WO3 and g-C3N4 was targeted and achieved, to construct a highly efficient direct Z-scheme heterojunction. Optimized binary composite holds the enhanced activity of about 2.6 folds of H2 generation rates than the thermally exfoliated g-C3N4. Further, CNT loading towards binary composite in an optimized weight ratio enhances the activity by 6.86 folds than the pristine g-C3N4. Notably, optimized ternary nanohybrid generates 15,918 μmol h-1. g-1cat of molecular H2, under natural solar light irradiation with 5 vol% TEOA as a sacrificial agent. Constructive enhancements deliver remarkable H2 production and dye degradation activities. Results evident that, the same system can be useful for pilot-scale energy generation and other photocatalytic applications as well.

Uptake of molybdate by adsorption onto industrial solid waste Fe(III)/Cr(III) hydroxide: kinetic and equilibrium studies

Removal of molybdate on to industrial solid waste Fe(III)/Cr(III) hydroxide as adsorbent has been investigated. Pretreated adsorbent was found to be more efficient in the uptake of molybdate compared to untreated adsorbent. Effect of pH on the adsorption was studied in the pH range 4.0 to 10.0. Optimum pH for maximum removal was found to be 4.0. Langmuir and Freundlich isotherm models were used to study the adsorption capacity of the adsorbent. The adsorption follows second order kinetics. No significant effect of temperature has been observed. Desorption studies showed that ion exchange mechanism is predominant.

Recycling Fe(III)/Cr(III) hydroxide, an industrial solid waste for the removal of phosphate from water

Industrial solid waste, Fe(III)/Cr(III) hydroxide, was investigated to assess the capacity for the removal of phosphate from aqueous solution. Langmuir and Freundlich isotherms were used to model the adsorption equilibrium data. The system follows both isotherms. Adsorption capacity was found to be 6.5 mg/g. Kinetic studies show that the adsorption obeyed second order kinetics. Thermodynamic parameters were evaluated. Overall adsorption process was endothermic and spontaneous. Optimum pH for phosphate adsorption was found to be 4.0. Effect of coexisting anions has also been examined.

Localized amyloidosis in nasopharyngeal carcinoma

A study of biopsies from 434 consecutive primary nasopharyngeal carcinomas revealed amyloid deposits in 54 (12%) of the tumours. Amyloid was present in all three histological types of nasopharyngeal carcinoma, but was more frequently observed in nonkeratinizing carcinomas. The amyloid deposits were patchy in distribution and occurred both within tumour cells and extracellularly. A neoplastic origin for this form of amyloid is suggested.

Hepatitis B virus surface antigen in glomerular immune complex deposits of patients with systemic lupus erythematosus

In view of a high prevalence of hepatitis B virus infection in the Malaysian population, indirect immunofluorescence examination for hepatitis B surface antigen (HBsAg) was routinely performed on renal biopsy specimen at the University Hospital, Kuala Lumpur, over a 3-year period. Examination of renal tissue from 259 patients, including 47 with systemic lupus erythematosus (SLE), revealed 43 cases with HBsAg in glomerular immune complexes. A significantly high proportion (30/43) of these were SLE patients. The deposits were granular in nature, situated in both the capillary walls and mesangium and associated with immunoglobulin deposition. Morphological patterns of lupus nephritis involved were focal proliferative (one case), diffuse proliferative (23 cases) and membranous (six cases). None of these patients showed clinical evidence of liver disease. The significance of these findings remains uncertain, but the possibility exists that the hepatitis B virus may have a role in the pathogenesis of SLE in the tropics where both SLE and HBs antigenaemia are common.

Morphological patterns of glomerular disease in renal biopsies from 1000 Malaysian patients

Adequately biopsied renal tissue received in the Department of Pathology, University Hospital, Kuala Lumpur from 1,000 consecutive Malaysian patients during an eleven year period between 1970 and 1981 was reviewed. The youngest patient was 6 days old and the oldest 80 years. Both sexes were equally represented. The majority of the patients were Chinese (71%) with Malays and Indians comprising most of the remainder. Over half the patients (50.4%) presented with the nephrotic syndrome. Other modes of presentation included systemic lupus erythematosus, proteinuria and haematuria separately or in combination and hypertension. Minimal change (25.7%) and proliferative glomerulonephritis (24.8%) were present in about equal numbers and together accounted for over half of the cases (50.5%). Lupus nephritis was the third most common diagnosis (18.4%). In addition, there were patients with focal glomerulonephritis (5.4%), membranous glomerulonephritis (5.5%), Berger's disease (5.8%), amyloidosis (0.6%) and end stage renal disease (4.0%).

Lupus nephritis and lupus band test

Twenty-seven patients with histologically confirmed lupus nephritis were studied to identify the incidence of lupus band and its significance to histological patterns of nephritis and complement levels. It was found that the kidney involvement is 2.5 times more frequent in lupus band positive patients. The association of a positive lupus and low C3 level signifies the presence of diffuse proliferative glomerulonephritis rather than membranous glomerulonephritis. The results, together with earlier reports, are discussed.

The efficacy of potassium-induced cardioplegia and topical hypothermia in the correction of congenital cardiac lesions

Myocardial metabolic, structural and functional preservation were evaluated in 44 patients who underwent open heart surgery under cardiopulmonary bypass, potassium cardioplegia and topical hypothermia. The duration of cardiac arrest varied from 14 to 87 minutes. Myocardial high-energy phosphates were not only adequately preserved but actually exceeded the control values during periods of cardiac arrest. Glycogen levels were decreased moderately and one to three fold increases in lactate/pyruvate ratios were detected. Myocardial ultrastructure was well preserved. Postoperative clinical recovery of the patients was excellent. The only patient who died from a low output syndrome showed no evidence of myocardial damage. The results of this study serve to illustrate the beneficial effects of potassium cardioplegia and topical hypothermia on myocardial preservation during prolonged periods of ischaemic cardiac arrest, as used for the correction of congenital cardiac lesions.

Pentastomiasis

Pentastomiasis is a zoonotic parasitic disease of man, first described by Pruner in 1847. The causative organisms are pentastomes (pentastomids), so called because of the presence of two pairs of anterior hooks and a mouth, which give the appearance of 5 openings. They are annulated but non segmented vermiform blood-sucking endoparasites. They are probably best classified as a separate phyllum, the Pentastomida. Of medical interest are two families of pentastomes namely Linguatulidae and Porocephalidae, of which species of the genera Linguatula and Armillifer (Porocephalus) are parasites of man.

Advanced retinoblastoma in Malaysian children

Twenty children with retinoblastoma are reviewed who were treated at the University Hospital, Kuala Lumpur over a 10-year-period. They constitute 6.6% of childhood malignancies and without exception all presented with advanced disease. Hereditary cases were notably absent in the the series probably because past cases have almost invariably succumbed without an opportunity to transmit the gene. With enucleation and radiotherapy six of the patients have survived from 2 to 12 years. The addition of vincristine and cyclophosphamide has not been associated with improved survival.

Teratoma in infancy and childhood: a ten-year review at the University Hospital, Kuala Lumpur

A ten-year review revealed a similarity in the incidence of teratoma in relation to other childhood tumors in Malaysian as compared with Caucasian children. The most common sites of origin were the sacropcoccygeal, gonadal, and retroperitoneal areas. The reason for the high incidence of retroperitoneal tumor in our series as compared with other countries is not clear. Late presentation and poor followup are associated with poor prognosis.

Amyloidosis in Malaysian aborigines (Orang Asli)

Material from 334 consecutive autopsies on Orang Asli subjects performed in the University Hospital, Kuala Lumpur between May 1967 and June 1978 was examined for amyloidosis. Nine positive cases were found, all in patients above 40 years of age, giving an age-corrected incidence of about 9%. In 6 cases, amyloidosis was probably secondary to tuberculosis. The remaining 3 cases exhibited a pericollagenous distribution characteristic of primary amyloidosis. Involvement of the heart and lungs was prominent. However, there were considerable similarities in the distribution and staining properties of the amyloid in the 2 groups. Though both the heart and kidney were frequently affected, the kidney was the most common organ to give rise to clinical symptoms. Infection probably plays a major contributory role in amyloidosis in the Orang Asli.

Acquired carbohydrate intolerance and cow milk protein-sensitive enteropathy in young infants

Sixty infants with acquired carbohydrate intolerance, 19 with protracted diarrhea, and 41 with features indistinguishable from acute infectious enteritis, were maintained on a lactose-free and cow milk protein-free formula for about eight weeks, after which jejunal biopsies were performed before and after oral provocation with cow milk protein. Following provocation, 43 infants showed mucocal abnormalities associated with marked reduction in the levels of all three disaccharidases. In one infant, mucosal change was unaccompanied by enzyme depletion. Six infants had enzyme depletion without visible mucosal changes. In ten infants the intestinal mucosa remained normal and there was no consistent pattern of change in the enzyme levels. The findings suggest that cow milk protein has a deleterious effect on the small bowel mucosa of young infants recovering from enteritis and may be an important contributing cause of acquired carbohydrate intolerance in these infants. In the management of young infants with acquired carbohydrate intolerance both the offending sugar and protein should be excluded.

Light and electron microstructure of a Sarcocystis sp. from the Malaysian long-tailed monkey, Macaca fascicularis

The ultrastructure of the cyst wall and zoites of a species of Sarcocystis from the skeletal muscles of a naturally-infected Malaysian long-tailed monkey, Macaca fascicularis, is described in detail. The wavy, electron-dense primary cyst wall is thin (55 nm) and invaginated. Cytophaneres are absent. The ground substance contains electron-dense granules and bundles of parallel, fibrillar elements in some areas. Thin trabeculae are present. The zoites measure 1.2 X 4.7 microns and have an interior conoid, 22 subpellicular microtubules, 50-60 micronemes, 4-6 rhoptries, and a posteriorly situated nucleus. Some ultrastructural aspects of the cyst wall and the zoites of this parasite resemble those of Sarcocystis species of the moonrat, rhesus monkey, tamarin, and baboon. The light microscopic appearance of this species from M. fascicularis also bears some resemblance to that of parasites from the four cases of human Sarcocystis reported in Malaysia. The cyst in all these human cases were thin-walled, with no cytophaners. Although the final hosts of these species of Sarcocystis are not known, it is quite possible that man, monkeys, and perhaps the moonrat (an insectivore) may serve as common intermediate hosts for one or several species of Sarcocystis.

Haemangiopericytoma: problems in diagnosis and management

Three cases of haemangiopericytoma with diverse modes of presentation are reported. The difficulties with clinical diagnosis are emphasized. There is no consensus on the best mode of treatment, and we have chosen radical surgical excision in the first instance, but have not hesitated to employ radiotherapy or chemotherapy as adjunctive treatment if the need has arisen. The clinical behaviour of this tumour is unpredictable; therefore the prognosis for life must remain uncertain.

Cows' milk protein-sensitive enteropathy. Combined clinical and histological criteria for diagnosis

Cows' milk protein enteropathy is recognised as a significant cause of persistent diarrhoea and malabsorption in young infants, but there are as yet no generally accepted diagnostic criteria. A combined clinical and histological approach to the diagnosis of cows' milk protein-sensitive enteropathy has been used in 15 patients, and the following set of criteria are proposed. (1) Clinical disease (diarrhoea with or without vomiting) while receiving cows' milk protein. (2) Clinical improvement on a diet free of cows' milk protein. (3) Normal or mildly abnormal histology of jejunal mucosa when taken 6-8 weeks after symptoms subside. (4) Histological relapse, with or without clinical relapse, after re-exposure to cows' milk protein.

HBAg-positive chronic liver disease associated with cirrhosis and hepatocellular carcinoma in the Senoi

Necropsy and clinical data show that primary hepatocellular carcinoma (PHC) is the commonest cancer among the Senoi (a Malaysian aboringine group). The other aboringine tribes do not appear to have this high predilection for liver cancer. In the necropsy series, PHS was present in 10 out of 22 Senoi patients with cirrhosis. All the 22 livers contained hepatocytes that stained with Shikata's orcein stain and specific immunoperoxidase and immunofluorescent stains for hepatitis B antigen (HBAg). This observation raises the strong possibility that hepatitis B may be an important etiologic factor in the development of cirrhosis and PHC in the Senoi. The reason for the high susceptibility of the Senoi for HB virus infection is not clear, and the role of aflatoxin in the pathogenesis of PHC in the Senoi has yet to be determined. That the Senoi are a numerically small community, maintaining their own unique dietary and social customs and living in readily accessible areas in the Malaysian jungle, makes them an ideal population for the study of factors in the etiology of liver cancer.

Xanthogranulomatous pyelonephritis in Malaysians

Eight cases of xanthogranulomatous pyelonephritis occurring in an oriental population are reported. The patients were mostly middle-aged, and there was a female preponderence. Nephrectomy controlled the disease in all cases. Diagnosis on clinical and radiological grounds is difficult, and it is often only made on pathological examination of the kidney after nephrectomy. The nature of the disease remains obscure.

Pseudotumours due to oil palm thorn injury

Three cases are reported in which pseudotumours developed in the hand following injury by oil palm thorns. In one patient there was a periosteal reaction of the proximal phalanx adjoining the site of injury. The lesions were excised, and the embedded oil palm thorn was identified in all three. The clinical and pathological features of the lesions and problems in their diagnosis are described. In every case the local tissue reaction was out of proportion to the size of the foreign body, raising the possibility that a toxic substance might have been released by the thorn.

Reaction of foetal tissues to intra-uterine subcutaneous injection of barium sulphate

Subpannicular injection of sterile barium sulphate in newborn rabbits produces an acute inflammatory response which is clearly seen at 24 hr and is well established at 48 hr. The processes of repair has begun by the 4th day with the appearance of proliferating capillaries and fibroblasts. In rabbit foetuses both vascular and cellular components of the acute inflammatory response are more prominent and appear earlier than in newborn rabbits, being well developed within 24 hr. The process of repair also begins earlier, proliferation of capillaries and fibroblasts being already prominent by 48 hr. By the 4th day the lesion is compact, less cellular and relatively avascular.

Hepatocellular carcinoma in the Malaysian Orang Asli

Necropsies were performed on 285 consecutively unclaimed Orang Asli bodies from Gombak Orang Asli Hospital during an eight-year period from May 1967 to April 1975. Of the 25 malignant neoplasms, hepatocellular carcinoma was by far the commonest (36%). The nine patients with this neoplasm had coexistant macronodular cirrhosis. There were 20 cases of cirrhosis; 45% of these had coexistant hepatocellular carcinoma. The 53,000 Orang Aslis living in West Malaysia comprise three tribes, the Negrito, Senoi, and Melayu Asli (Proto Malays). The Sinoi appear to have a high predilection for liver cancer, all our nine cases occurring in this group. These aboriginal people live in the jungles where they practice shifting cultivation and maintain their own dietary and social customs. Detailed studies of their dietary habits may provide a clue to the etiology of liver cancer in these people.

The effect of intrauterine phrenic nerve division on the development of the lungs and diaphragm in fetal rabbits

Intrauterine division of the left phrenic nerve has been successfully performed in rabbit fetuses as early as the 21st day of gestation, prior to alveolar differentiation. This procedure results in intrauterine atrophy of the ipsilateral hemidiaphragm and hypertrophy of the contralateral side. Light and electron microscopic studies have shown no interference with the subsequent maturation of the lung.

Diet-induced aortic atherosclerosis in Malaysian long-tailed monkeys (Macaca irus)

Moderate hypercholesterolaemia has been produced in eight adult male M. irus monkeys by feeding an egg-toast preparation containing butter and 0.14 per cent. total cholesterol. At autopsy, after two to four years of persistent hypercholesterolaemia, there was massive fatty streaking of the aorta involving 21 to 78 per cent. of the intimal surface. The distribution and morphology of the fatty streaks was similar to that in man. In addition, there were fibrous plaques including "soft" lipid-rich atherosclerotic plaques identical to their human counterpart. There was no grossly detectable thromobosis, haemorrhage or ulceration. Atherosclerotic lesions were also present in the coronary, carotid, subclavian, iliac and femoral arteries. In a control group of monkeys fed a low-fat, cholesterol-free diet, arterial lesions were identical in type and extent to those in freshly captured wild monkeys.

THE EFFECT OF INJECTION OF HYDROCORTISONE INTO RABBIT CALCANEAL TENDONS

This experiment demonstrates that infiltration of hydrocortisone into rabbit calcaneal tendons has a direct effect on the tendon, producing necrosis of collagen at the site of injection. The repair of the lesion so produced is incomplete even after eight weeks, and is often complicated by dystrophic calcification. Similar morphological changes may account for spontaneous rupture of tendons in patients receiving steroid infiltration.