Activation of striatal dopamine receptors induces pain inhibition in rats

Summary In the rat, elevating dopamine content in corpus striatum with electrical stimulation of substantia nigra or direct administration of apomorphine (50–200g) into the lateral cerebral ventricle or apomorphine (2–10g) into the caudate-putamen complex decreased pain sensitivity (as shown by an increase in the latency to hind-paw lick in the hot plate test). Furthermore, the decreased pain sensitivity after the central administration of apomorphine was antagonized by pretreatment with haloperidol (a dopamine antagonist). On the other hand, lowering dopamine content in corpus striatum with electrolytic destruction of substantia nigra and 6-hydroxydopamine lesions to the substantia nigra, as well as direct injection of haloperidol into the lateral cerebral ventricle or caudate-putamen complex increased pain sensitivity. The data indicate that activation of striatal dopamine receptors in rat brain induces pain inhibition.     

Effects of adenosine 3′, 5′-cyclic monophosphate on thermoregulation in both rats and rabbits

Summary The effects of intraventricular administration of dibutyryl adenosine 3, 5-cyclic monophosphate (db cyclic AMP) on the thermoregulatory responses of unanesthetized rats and rabbits to different ambient temperatures (T_a) were assessed. Administration of db cyclic AMP (10–60 mM) produced dose-dependent hypothermia in both rats and rabbits at T_a 2–22 °C. The hypothermia in response to db cyclic AMP was due to decreased metabolic heat production and cutaneous vasodilatation. There was no change in respiratory evaporative heat loss. In contrast, in the heat (30–32 °C), db cyclic AMP administration produced dose-dependent hyperthermia in these animals. The hyperthermia was due to increased metabolism (due to muscular shivering) and decreased heat losses. The reduction in heat losses was shown by a decrease in both cutaneous circulation and respiratory evaporative heat loss. The data demonstrate that the thermoregulatory responses induced by central administration of db cyclic AMP are T_a-dependent.     

Modification of vascular response to synthetic oxytocin by oestrogen in rabbit

Intravenously administered oxytocin caused a dose-related fall in blood pressure of the rabbit. When oxytocin was administered in oestrogen-primed animals, the depressor response was converted to a pressor one "Oxytocin reversal". The "oxytocin reversal." was abolished after treatment with dihydroergotamine, hexamethonium or adrenalectomy. The "oxytocin reversal" did not appear in reserpinized animals.     

Concurrent cisplatin and radiotherapy in advanced head and neck cancer

Management of Head and Neck Cancers poses a challenge inspite of several advances because of poor success in terms of response rate, survival and reduced morbidity of the patients. In the present study 30 untreated histologically proven cases of head and neck cancers were subjected to weekly radiotherapy with adjuvant chemotherapy (cisplatin 30 mg/m² intravenously). This study group was compared with a group of 30 patients who were given only radiotherapy. Results have shown that combination of chemotherapy with radiotherapy gives a significantly better results in tumour as well as nodal response with minimal toxicities.     

Cancer Patterns in the Middle East Special Report from the Middle East Cancer Society

To update its cancer statistics, the newly established Middle East Cancer Society examined the cancer frequency patterns in Egypt and the Gaza Strip. The results revealed differing overall patterns. For men the highest frequencies were found for lymphoma, bladder cancer and cancers of the oral cavity and pharynx in Egypt, and for lung cancer, leukaemia and lymphoma in Gaza. For women, breast cancer had the highest frequency in both areas, followed by cancers of the oral cavity and pharynx in Egypt, and leukaemia and lymphoma in Gaza. The distribution of cancer occurrence by organ system also varied. In the light of the different ethnicities, lifestyles, socioeconomic levels and carcinogenic exposure among the countries of the Middle East, this kind of comparison can provide the background for more sophisticated approaches for discerning risk factors in cancer. We believe that further cooperation among participating countries will overcome the present limitations in data collection, registration and access.     

Depression in women--issues in evaluation and management

Depression is probably the most common psychiatric disorder in women. Women are a vulnerable group of depression due to psychological, social and biological factors. Marital relationships, social support, roles and self esteem are factors that contribute to depression. In addition, several periods in women's life relating to the reproductive cycle are periods of increased vulnerability. Management of depression in women should consist of detailed assessment of all the above factors. Drug treatment of depression in women requires an in depth understanding of pharmacokinetics of the drugs used and possible drug interactions. Treatment of depression in women should integrate both psychosocial and biological treatment modalities.     

Effects of irradiation on nasal mucociliary clearance in head and neck cancer patients

A prospective longitudinal study was conducted on fifty patients of histopathologically confirmed head and neck cancer with the main aim to assess the nasal mucociliary clearance, pre-and post-irradiation; and to compare the findings with the healthy non-irradiated age and sex-matched controls. All the patients underwent saccharin particle test for nasal mucociliary clearance before commencement of radiation therapy and again within 6 months of completion of radiation therapy. The difference between the saccharin perception times of nasal mucosa in the healthy non-irradiated controls and the pre-irradiated head and neck cancer patients were statistically inssignificant (P>0.05). But, the difference between the saccharin perception times of nasal mucosa in the pre-and post-irradiated head and neck cancer patients was found to be statistically significant (P=0). It is concluded that even indirect irradiation of nasal mucosa in head and neck cancer patients significantly affect its ciliary activity. Significance of total radiation dosage along with chemotherapy in some cases was also studied.     

Supravital staining: It's role in detecting early malignancies

The efficacy of supravital staining in the detection of malignancies in oro and oropharyngeal lesions and its role in the detection of malignant changes in premalignant lesions were studied. This prospective study comprises 90 cases of clinically suspicious lesions and it was done over a period of 3 years. Most of the patients had multiple risk factors for the development of malignancy. All underwent staining with a modified solution of 1% toluidine blue (TB). In our study the overall sensitivity was 97.29% and the specificity was 62.5%.     

ROLE OF INTERMEDIARY BIOMARKERS IN DETERMINING THE ANTICANCER EFFICACY OF MARINE COMPOUNDS

In the present study, two of the probable an umor marine compounds, manzamine A and sarcophine, were screened using benzo[a]pyrene (BP)-derived DNA adduct formation in MCF-7 cells as intermediary biomarker. Briefly, MCF-7 cells were treated with the compounds for 24 h followed by treatment with BP (0.5 μM). After 24h incubation, cellular DNA was isolated and analyzed for BP-derived DNA adducts by ³²P-postlabeling technique. Manzamine A and sarcophine increased the BP-DNA adducts by 2 to 4-folds. Further, manzamine A (50 μM) substantially down regulated the expression of p53 while sarcophine (50 μM) slightly induced the level of p21. The residual DNA repair ability was almost completely abolished by manzamine A while sarcophine was ineffective. Based on our preliminary results, these compounds may be classified as potential genotoxic.     

Candida biofilm resistance.

Device-related infections in most nosocomial diseases can be traced to the formation of biofilms (microbial communities encased within polysaccharide-rich extracellular matrix) by pathogens on surfaces of these devices. Candida species are the most common fungi isolated from these infections, and biofilms formed by these fungal organisms are associated with drastically enhanced resistance against most antimicrobial agents. This enhanced resistance contributes to the persistence of this fungus despite antifungal therapy. Candida biofilms exhibit enhanced resistance against most antifungal agents, except echinocandins and lipid formulations of AmB. The expression of drug efflux pumps during the early phase of biofilm formation and alterations in membrane sterol composition contribute to resistance of these biofilms against azoles. Metabolic dormancy and ECM do not appear to contribute to resistance, although in a mixed-species biofilm, ECM does retard the diffusion of drugs across biofilm. These multifactorial mechanisms of resistance in fungal biofilms constitute a broad-spectrum defense that is effective against many types of antifungal agents, and represent a common theme present across microbial biofilms.