Production of Cu using natural cobalt target and its separation using ascorbic acid and common anion exchange resin

⁶¹Cu was produced by ^natCo(α, xn)⁶¹Cu reaction. ⁶¹Cu production yield was 89.5 MBq/μAh (2.42 mCi/μAh) at the end of irradiation (EOI). A simple radiochemical separation method using anion exchange resin and ascorbic acid has been employed to separate the product radionuclide from inactive target material and co-produced non-isotopic impurities. The radiochemical separation yield was about 90%. Radiochemical purity of ⁶¹Cu was >99% 1 h after EOI. Final product was suitable for making complex with N₂S₂ type of ligands.     

Reconstructive challenges in war wounds

War wounds are devastating with extensive soft tissue and osseous destruction and heavy contamination. War casualties generally reach the reconstructive surgery centre after a delayed period due to additional injuries to the vital organs. This delay in their transfer to a tertiary care centre is responsible for progressive deterioration in wound conditions. In the prevailing circumstances, a majority of war wounds undergo delayed reconstruction, after a series of debridements. In the recent military conflicts, hydrosurgery jet debridement and negative pressure wound therapy have been successfully used in the preparation of war wounds. In war injuries, due to a heavy casualty load, a faster and reliable method of reconstruction is aimed at. Pedicle flaps in extremities provide rapid and reliable cover in extremity wounds. Large complex defects can be reconstructed using microvascular free flaps in a single stage. This article highlights the peculiarities and the challenges encountered in the reconstruction of these ghastly wounds.KEY WORDS: Delayed reconstruction, reconstructive challenges, war wound, wound debridement     

Synchronous Tricompartmental Benign CNS Tumors with Tonsillar Herniation, Cervicodorsal Syringomyelia and Hydrocephalus

In this study, three primary central nervous system tumors of different histological cell types occurring together without neurofibromatosis are reported. These included a sellar pituitary adenoma with apoplexy, a large torculo-tentorial meningioma in the posterior fossa, and a cervical spinal intramedullary schwannoma. Displacement of primitive multipotent cells in different central nervous system compartments or the oncogenic effects of activated signaling of growth factor receptors are the proposed pathophysiological mechanisms for the simultaneous genesis of different types of tumors. There was associated tonsillar herniation, cervicodorsal syringomyelia, and hydrocephalus. The radiological features and treatment strategy of these rare synchronous tumors are highlighted.     

Erythrocytic vacuolar rafts induced by malaria parasites

Studies in the past year displaced long-standing dogmas and provided many new molecular insights into how proteins and solutes move between the erythrocyte plasma membrane and the malarial vacuole. Highlights include a demonstration that (1) detergent-resistant membrane (DRM) rafts exist in the red cell membrane and their resident proteins are detected as rafts in the plasmodial vacuole, (2) a voltage-gated channel in the infected red cell membrane mediates uptake of extracellular nutrient solutes, and (3) intraerythrocytic membranes transport a parasite-encoded adherence antigen to the red cell surface.     

Short report: hepatitis b infection and severe Plasmodium falciparum malaria in Vietnamese adults

We investigated the prevalence of infection with hepatitis B virus among adult Vietnamese patients hospitalized for severe Plasmodiumfalciparum malaria. Sera from patients admitted with severe malaria in Ho Chi Minh City, Vietnam, between May 1991 and January 1996 were assayed for hepatitis B surface antigen (HB(s)Ag) by a commercial enzyme-linked immunosorbent assay kit. The overall prevalence of HB(s)Ag was 23.77% (77 of 324). This was higher than reported estimates of prevalence in the general catchment population for the study hospital (mean, 9.8%; range, 9-16%). No association was found between risk of death caused by severe malaria and HB(s)Ag. Patients admitted with cerebral malaria had a slightly greater risk of registering positive for HB(s)Ag (relative risk, 1.28; 95% confidence interval, 1.04-1.58) relative to other manifestations of severe malaria. Chronic infection with hepatitis B virus may be a risk factor for severe malaria.     

α-Thalassemia Among Tribal Populations of Eastern India

Five hundred and thirteen unrelated subjects belonging to various tribes of West Bengal, Arunachal Pradesh and Assam in Eastern India, were screened for the presence of α-thalassemia (thal) gene deletion(s) as a possible cause of unexplained anemia (Hb <11 g/dL and/or MCH <28 pg, MCV < 78 fL). As reported earlier, β-globin gene mutant alleles were found with a frequency of up to 20% in some tribes. In the present study, α-globin gene deletion alleles were found in 18% of subjects from West Bengal, 3.9% from Arunachal Pradesh and 3.84% from Assam tribesmen. Coexistence of α- and β-globin gene abnormalities was observed in up to 18% of some tribal groups. The high inbreeding rate and lack of appropriate medical care make these populations particularly vulnerable.     

Independent release of oxytocin and vasopressin during parturition in the rabbit

1. Oxytocin and vasopressin were assayed in samples of blood collected from seven conscious rabbits during parturition.2. Oxytocin was detected in the blood in ten out of fourteen samples collected during the expulsion of one or more foetuses. Four samples contained 6-100 muu./ml., three 100-200 muu./ml. and three 200-500 muu./ml.3. Vasopressin was detected in six blood samples collected during the delivery of foetuses but in only one experiment did the amount exceed that found in the corresponding control sample collected before or after delivery.4. When both hormones were detected in the same blood sample, the ratio of oxytocin to vasopressin varied from 5:1 to at least 26:1.5. It is concluded that, while oxytocin may not be essential for parturition in the rabbit, stretching of the birth canal during the expulsion of foetuses normally acts as a stimulus for the reflex release of oxytocin from the neurohypophysis and that oxytocin is released independently of vasopressin.     

Blood levels of oxytocin and vasopressin during suckling in the rabbit and the problem of their independent release

1. Oxytocin and vasopressin were assayed in samples of blood collected from conscious rabbits during suckling. The milk yields were determined from the weight gain of the litters.2. With normal milk yields (35-155 g), relatively high concentrations (31-375 muu./ml.) of oxytocin were present in the blood but vasopressin was detected in only one out of eight samples. It is concluded that the release of oxytocin by the milk-ejection reflex is essential for normal milk removal in the rabbit and that this hormone is released independently of vasopressin.3. When the milk yield did not exceed 15 g, an amount which could be removed by passive withdrawal from the mammary gland, vasopressin was detected in four out of five blood samples but none contained a detectable concentration of oxytocin. This result can be explained by the intervention of emotional stress which is known to block the milk-ejection reflex but which acts as a stimulus for the release of vasopressin.4. Emotional stress could inhibit the milk-ejection reflex either centrally by blocking the release of oxytocin, or peripherally by blocking the response of the mammary gland to circulating oxytocin. The absence of the hormone in blood during ineffectual suckling suggests that the block is central.     

DNA base excision repair of 5-hydroxymethyl-2'-deoxyuridine stimulates poly(ADP-ribose) synthesis in Chinese hamster cells

5-Hydroxymethyl-2'-deoxyuridine (hmdUrd) is incorporated intoDNA as a thymidine analog resulting in extensive substitutionof thymine residues with 5-hydroxymethyluracil (hmUra) residues.These hmUra residues are then subject to excision by actionof hmUra-DNA glycosylase. 3-Aminobenzamide (3AB), an inhibitorof poly(ADP-ribose) synthesis, is toxic to cells that incorporateand repair hmdUrd. To demonstrate that incorporation and repairof hmdUrd stimulates synthesis of poly(ADP-ribose) from intracellularNAD, V79 hamster cells were treated with hmdUrd and intracellularNAD levels were measured. Following hmdUrd treatment, NAD levelsfell markedly (80–90%) within 4 h and remained low forat least 10 h, before partially recovering by 24 h. The degreeof NAD lowering was dose dependent and paralleled net hmdUrdincorporation. The NAD lowering was largely prevented by concurrenttreatment with 4 mM 3AB. No effects on NAD levels were seenfollowing treatment with deoxythymidine or bromodeoxyuridine,which are incorporated into DNA but, in contrast to lundUrd,are not repaired. When the incorporation of hmdUrd into DNAwas blocked with hydroxyurea or aphidicolin, no NAD loweringwas seen. HmdUrd also did not produce lowering of NAD concentrationsin mutant cell strains deficient in the ability either to incorporatehmdUrd into DNA or to repair hmdUrd from DNA. These resultsdemonstrate that synthesis of poly(ADP-ribose) resulted directlyfrom the incorporation into DNA of the nucleoside hmdUrd andits subsequent repair. These results unequivocally demonstratethat the initiation of normal DNA base excision repair by itself,and not DNA damage per se, is a sufficient stimulus for theinduction of poly(ADP-ribose) synthesis.     

Extrahypothalamic neurohypophysical peptides in the rat central nervous system

Vasopressin (VP) and oxytocin (OT) have been identified in a number of extrahypothalamic areas, both by immunohistochemistry and by radioimmunoassay. Because of the incomplete nature of the data available, we have conducted a survey of the VP and OT concentrations in the rat central nervous system. VP and OT were readily detectable in all areas studied. With the exception of the amygdala, OT concentrations were generally 2-4 times those of VP. The physiological function of neurohypophysial hormones in these extrahypothalamic areas is essentially unknown.