TSH secreting pituitary adenoma

Thyrotropin (TSH) secreting pituitary adenomas are a very rare cause of hyperthyroidism. They typically present with signs and symptoms of hyperthyroidism and rarely can be asymptomatic. TSH secreting tumors account for 1 percent of all pituitary adenoma. They are a rare cause of thyrotoxicosis in which adenomas completely or partially lose feedback regulation of thyroid hormones and lead to sustained stimulation of thyroid gland. The most definitive treatment of thyrotropin (TSH)-secreting pituitary adenomas is transsphenoidal removal of tumor after restoring euthyroidism. We report a case of pituitary adenoma associated with elevated serum free thyroid hormones and non-suppressed TSH levels.

Effect of caffeine treatment on low-dose γ- irradiation-induced chromatid-type aberrations in human leukemia cells and human normal fibroblast cells in culture

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Background: It is estimated that low dose radiation can increase the risk of cancer as well as mutations. However, the interaction of low dose radiation with caffeine has not been adequately investigated. We investigated the effects of caffeine on low dose- gamma-radiation-induced chromosomal damage in human T leukemia cells (Jurket T-cells) and two normal human fibroblast cell lines (AG1522 and GM 2149). Method: Jurkat cells were maintained in RPMI 1640 medium and fibroblast in alpha-minimal essential medium (MEM) All cells were incubated at 37o C in a humidified atmosphere of 5% CO2 in air. Cells from the exponential phase were treated with 1 mg/ml caffeine ( control cells received same amount of solvent) and irradiated with low doses (3, 5, 10, 20 and 40 cGy,), using a 137 Cs-gamma radiation source. Colcemid at a concentration of 0.1 μg/ml was added to every flask. Cells were fixed in methanol: acetic acid solution and stained with Giemsa. 100 irradiated and un-irradiated metaphase- like cells were scored for chromatid-type aberrations. Results: Low dose gamma-radiation increased the levels of chromatid breaks(dose dependent) in both normal and cancer cells; however, cancer cells appeared to be more sensitive than the normal cells. Caffeine treatment markedly increased chromatid aberrations in Jurkat T-cells at all radiation doses but not in normal cells. Previously, we reported that caffeine eliminates gamma-ray-induced G2 delay in other human tumor cells but not normal cells (Jha, et.al., Radiat. Res. 157, 26–31, 2002). Conclusions: The mechanisms that may underlie this differential effect of caffeine in cancer and normal cells are unknown, but if one result of a G2 delay is to allow more time for chromosome breakage rejoining processes to occur, then elimination of this delay by caffeine in tumor cells but not normal cells might account for the difference. To the extent these observations are generally true for tumor vs normal cells, the differential sensitization could have an impact in improving the efficacy of radiation therapy.

No significant financial relationships to disclose.

REVIEW paper: pathophysiology of myocardial reperfusion injury: the role of genetically engineered mouse models

Coronary heart disease is the leading cause of death worldwide, affecting millions of men and women each year. Following an acute myocardial infarction, early and successful reperfusion therapy with thrombolytic therapy or primary percutaneous coronary intervention plays an important role in minimizing tissue injury associated with cessation of blood flow. The process of restoring blood flow to the ischemic myocardium, however, can induce additional injury. This phenomenon, termed myocardial ischemia-reperfusion (MI-R) injury, can paradoxically reduce the beneficial effects of myocardial reperfusion. MI-R injury is characterized by the formation of oxygen radicals upon reintroduction of molecular oxygen to the ischemic tissue, resulting in widespread lipid and protein oxidative modifications, mitochondrial injury, and cell death. In addition, studies have shown that MI-R is characterized by an inappropriate immune response in the microcirculation, resulting in leukocyte-endothelial cell interactions mediated by the upregulation of both leukocyte and endothelial cell adhesion molecules. Furthermore, MI-R ameliorates the production of certain cardioprotective factors such as nitric oxide. Advances in the generation of genetically modified mouse models enable researchers to identify the functional importance of genes involved in these processes.

Dietary n-3 fatty acids decrease the leukotriene B4 response ex vivo and the bovine serum albumin-induced footpad swelling index in New Hampshire hens

The effects of feeding New Hampshire hens different amounts of n-6 and n-3 fatty acids on plasma and immune tissue fatty acid profiles, leukotriene (LT) B4 response ex vivo in stimulated thrombocytes, serum non-esterified fatty acid (NEFA) concentrations, and bovine serum albumen (BSA)-induced footpad swelling index were investigated. Seventy-two New Hampshire hens (n = 24/treatment) were fed diets supplemented with 3.0% sunflower oil (Diet I), 1.5% sunflower oil + 1.5% fish oil (Diet II), or 3.0% fish oil (Diet III). After 46 d on experimental diets, concentrations of C20:5n-3 and C22:6n-3 were higher in plasma, thrombocytes, and spleens of hens fed Diet II and III compared with hens fed Diet I (P ≤ 0.05). Thrombocytes from hens fed Diet III that were stimulated ex vivo with calcium ionophore A23187 produced less LTB4 than those from hens fed Diets I and II (P < 0.05). The serum NEFA concentrations were 0.31 ± 0.12, 0.25 ± 0.08, and 0.17 ± 0.06 mEq L-1 for hens fed Diets I, II, and III, respectively (P = 0.07). The cell-mediated immune response, based on results of a BSA-induced footpad swelling index at 48 h, was less in hens fed Diet III (P < 0.05) compared with hens fed Diets I or II. These results indicate that increasing the concentration of n-3 fatty acids in diets fed to New Hampshire hens might depress cell-mediated immunity and the pro-inflammatory LTB4 response. Key words: N-3 fatty acids; Leukotriene B4; Thrombocytes

Preceding infections and anti-ganglioside antibodies in patients with Guillain-Barré syndrome: a single centre prospective case-control study

Preceding infections and anti-ganglioside antibodies were assessed among 80 Guillain-Barré syndrome (GBS) patients and 125 controls. Previous infections were more frequent among GBS patients than among controls (p <0.0001), and had a significant association with axonal subtype compared with acute inflammatory demyelinating polyneuropathy (AIDP) (29/46 vs. 10/34 patients; p <0.05). Campylobacter jejuni (26%) was the most common preceding infection among GBS patients, followed by Mycoplasma pneumoniae (15%). Anti-ganglioside antibodies were detected more frequently among GBS patients than among controls (65/80 vs. 13/125; p <0.001), and a higher proportion of axonal cases had these antibodies than did AIDP patients (43/46 vs. 22/34; p <0.01).

Studies on Pharmacognostical features of Curcuma domestica Val

The microscopic and macroscopic characters of the rhizome of Curcuma domestica Val. were studied. The behavior of the powdered drug in the presence of various chemicals was also studied. Preliminary phytochemical screening on the various extracts of the rhizome was done in order to ascertain the various chemical constituents present. These studies were carried out to identify this plant for future research work.

Maternal dietary n-3 fatty acids alter immune cell fatty acid composition and leukotriene production in growing chicks

The effect of feeding different amounts of n-6 and n-3 fatty acids (FA) to hens on immune tissue FA composition and leukotriene production of hatched chicks was investigated. Hens were fed diets supplemented with either 3.0% sunflower oil (Diet I), 1.5% sunflower+1.5% fish oil (Diet II), or 3.0% fish oil (Diet III) for 46 days. The hatched chicks were fed a diet containing C18:3n-3, but devoid of longer chain n-6 and n-3 FA, for 21 days. Spleen docosahexaenoic acid (DHA) content was higher in chicks from hens fed Diet III (P<0.05). The bursa content of arachidonic acid was lower in chicks hatched from hens fed Diet III (P<0.05), and the ratio of n-6 to n-3 FA was significantly higher in bursa of chicks hatched to hens fed Diet I (P<0.05). Eicosapentaenoic acid (EPA) and DHA contents were higher in bursa of chicks hatched from hens fed Diet III (P<0.05). Thrombocytes from chicks hatched to hens fed Diet III produced the most leukotriene B(5) (LTB(5)). The ratio of LTB(5) to LTB(4) concentrations was also highest (P<0.05) in chicks hatched to hens fed Diet III. These results indicate that modulating maternal dietary n-6 and n-3 FA may alter leukotriene production in chicks, which could lead to less inflammatory-related disorders in poultry.

Delayed synapsing muscles are more severely affected in an experimental model of MuSK-induced myasthenia gravis

Myasthenia gravis can be induced in mice by injecting the extracellular domain of rat muscle-specific kinase (MuSK), a transmembrane receptor tyrosine kinase involved in agrin signaling at the neuromuscular junction. About 5-10% of human myasthenia gravis patients have autoantibodies against MuSK. Here we have examined mouse neuromuscular junctions following MuSK immunization in two groups of muscles that can be distinguished on the basis of the timing of neuromuscular synaptogenesis and their response to perturbation of agrin signaling. We used confocal microscopy to characterize the distribution and expression of nicotinic acetylcoline receptors and of two presynaptic makers, neurofilament protein and synaptophysin. We observed disruption of neuromuscular junctions in all muscles examined in this model of myasthenia gravis. However delayed-synapsing muscles, including the diaphragm, sternomastoid and tibialis posterior, were significantly more severely affected than fast-synapsing muscles, including the intercostal, adductor longus and tibialis anterior. These results suggest a basis for the differential susceptibility of muscles in different classes of myasthenia gravis patients, including patients with autoantibodies against MuSK.

Non-hypertensive intracerebral haemorrhage: some interesting observations

Hypertension is the commonest cause of intracerebral hemorrhage (ICH) but non-hypertensive intracerebral hemorrhages (NHICH) are not rare. We report three interesting cases of NHICH subsequent to amyloid angiopathy, alcoholic hepatitis and amphetamine abuse. They suggest the importance of recognizing these conditions and need for urgent specific therapy which may play a vital role in therapeutic planning and prevention of ICH.

Population growth, human development, and deforestation in biodiversity hotspots

Human population and development activities affect the rate of deforestation in biodiversity hotspots. We quantified the effect of human population growth and development on rates of deforestation and analyzed the relationship between these causal factors in the 1980s and 1990s. We compared the averages of population growth, human development index (HDI, which measures income, health, and education), and deforestation rate and computed correlations among these variables for countries that contain biodiversity hotspots. When population growth was high and HDI was low there was a high rate of deforestation, but when HDI was high, rate of deforestation was low, despite high population growth. The correlation among variables was significant for the 1990s but not for the 1980s. The relationship between population growth and HDI had a regional pattern that reflected the historical process of development. Based on the changes in HDI and deforestation rate over time, we identified two drivers of deforestation: policy choice and human-development constraints. Policy choices that disregard conservation may cause the loss of forests even in countries that are relatively developed. Lack of development in other countries, on the other hand, may increase the pressure on forests to meet the basic needs of the human population. Deforestation resulting from policy choices may be easier to fix than deforestation arising from human development constraints. To prevent deforestation in the countries that have such constraints, transfer of material and intellectual resources from developed countries may be needed. Popular interest in sustainable development in developed countries can facilitate the transfer of these resources.

Thallium poisoning presenting as paresthesias, paresis, psychosis and pain in abdomen

Due to involvement of multiple systems, thallium poisoning is notorious for complexity and seriousness as symptoms of toxicity are non-specific and diverse. Alopecia and painful neuropathy are its cardinal features, others being gastrointestinal disturbances, encephalopathy, tachycardia, ataxia, hepatorenal and cardiac damage etc. We report a case of thallium poisoning who presented initially with gastrointestinal symptoms and later developed neurological features (peripheral neuropathy and delirium). Various diagnoses were entertained in this case and thallium poisoning was suspected only after he developed alopecia and neuropsychosis. He made a significant recovery by conservative management in spite of delay in diagnosis. We conclude that a high level of suspicion should be kept for thallium poisoning, especially in patients with painful, peripheral neuropathy and gastrointestinal symptoms which appear earlier than alopecia, since prognosis is more rewarding with early diagnosis, leading to complete recovery.

Dietary (n-3) fatty acids alter plasma fatty acids and leukotriene B synthesis by stimulated neutrophils from healthy geriatric Beagles

The study objective was to determine the effect of feeding food enriched in (n-3) fatty acids (FA) on plasma FA profiles and leukotriene B (LTB) synthesis by stimulated peripheral blood neutrophils from dogs. For 36 weeks, two groups of dogs (n = 5) were fed food that contained either a low ratio of (n-6)-(n-3) FA (1.31:1; fish oil-enriched food) or a high ratio of (n - 6)-(n-3) FA (40.6:1; corn oil-enriched food). Consumption of food enriched in fish oil resulted in higher plasma concentrations of eicosapentaenoic acid and docosahexaenoic acid and lower concentrations of arachidonic acid. Neutrophils from dogs fed fish oil-enriched food produced 7.6-fold more LTB(5)(P = 0.002), and the ratio of LTB(5)-LTB(4) concentrations was 8.3-fold higher (P < 0.001) compared with dogs fed corn oil-enriched food. Dietary FA can modulate leukotriene production by neutrophils in dogs, and suggests that foods enriched in (n-3) FA from fish oil may have value in the treatment of canine inflammatory diseases.

Morphine for post-caesarean section analgesia: intrathecal, epidural or intravenous?

INTRODUCTION

Good analgesia is important after a caesarean section but there are no studies to date that compared intrathecal (IT), epidural (EP) and intravenous patient-controlled analgesia (IV PCA) morphine for post-caesarean section analgesia. In this study, we compared the differences in the quality of analgesia and side effects rendered by IT, EP and IV PCA morphine for post-caesarean section analgesia.

METHODS

We systematically collected and reviewed the data of 949 women who received IT, EP or IV PCA morphine for post-caesarean analgesia during a six-month period. We reviewed the patients 24 hours after surgery and recorded the type of analgesia, the use of adjuncts, pain scores, side effects and degree of satisfaction with the mode of analgesia. The data was captured in an electronic database and analysed.

RESULTS

IT morphine was the predominant method of post-caesarean analgesia, accounting for 89.5 percent of the cases. Non-steroidal anti-inflammatory drugs (NSAIDs) were more commonly used in the IT and EP group (IT 76 percent, EP 80 percent and IV PCA 49 percent, p-value is less than 0.05). IT morphine group had a significantly lower pain score at rest (p-value is less than 0.001) and on movement (p-value is less than 0.05) when compared with IV PCA group. EP morphine also resulted in a lower pain score than IV PCA on movement (p-value is less than 0.05). There was no difference in pain scores between EP and IT morphine. In the subgroup analysis of patients who did not receive NSAIDs, IT and EP morphine group also registered lower pain scores at rest and on movement than IV PCA group (p-value is less than 0.05). There was no difference in the satisfaction scores among the three groups.

CONCLUSION

The use of IT and EP morphine was associated with lower pain scores than IV PCA morphine at rest and on movement in the first 24 hours after caesarean section. No severe side effects were found.

Optimization of assay conditions for leukotriene B4 synthesis by neutrophils or platelets isolated from peripheral blood of monogastric animals

Neutrophils are involved in inflammation through leukotriene (LT) production. The predominant proinflammatory leukotriene released from neutrophils is LTB4, which serves as a biological marker of inflammation. The purpose of this study was to optimize the conditions ex vivo for LTB4 production by neutrophils from horses and dogs, and platelets from chickens. Optimal production of LTB4 was characterized by incubation time (2.5, 5, 10, 15 or 20 min), temperature (25 or 37 degrees C), and calcium ionophore A23187 concentration (0.1, 1, 10 or 20 microM). Incubation longer than 2.5 min did not increase production of LTB4 in chickens or horses; in dogs, incubation for 2.5 and 10 min resulted in the highest concentrations of LTB4 (P<or=0.05). In all species, incubation at 37 degrees C resulted in optimal LTB4 production (P<or=0.05). Production of LTB4 was highest when neutrophils or platelets were stimulated with 20 microM calcium ionophore in all species (P<or=0.05). These results indicate that neutrophils isolated from horses and dogs, and platelets isolated from chickens, are capable of producing LTB4. Optimum conditions for LTB4 production are similar in all three species.