Biotechnological production and insecticidal activity of the Escherichia coli

The most important research objectives concerning Bacillus thuringiensis (Bt) are to find more potent strains and to identify new insecticidal genes with broad host ranges. A local isolate of subspecies aegypti, BtC18, showed broad insecticidal activity against lepidopteran, dipteran, and coleopteran insects. Vegetative insecticidal proteins (Vips) are toxins isolated from Bt. Here, we report the cloning and overexpression of the vip3Ah1 gene in E. coli and provide analysis of its insecticidal activity. An 89.5-kDa Vip3Ah1 protein is secreted by Bt during the vegetative growth phase. The full 2.3-kbp length of vip3Ah1 coding region was isolated from genomic DNA, cloned into pCR2.1 vector, subcloned into pET-30a expression vector, and overexpressed in E. coli under the control of the inducible T7 promoter. The heterologously produced Vip3Ah1 protein (≈ 30% of total protein) was found in both soluble and insoluble forms. The nucleotide sequence had 99% identity with that of previouslyisolated vip3Aa genes. Expressed protein was purified, blotted, and assayed against the lepidopteran pests black cutworm (BCW) (Agrotis ipsilon; LC50 46 ng cm-2) and tobacco hornworm (THW) (Manduca sexta; LC50 27 ng cm-2). The overexpressed Vip3Ah1 protein showed significant insecticidal activity against black cutworm and tobacco hornworm.

Development of palliative care in lebanon obstacles and opportunities

Palliative care focuses on relieving suffering in patients with serious illness. Patients who receive palliative care have better control of distressing symptoms, are less likely to suffer from depression and have a better quality of life. Although palliative care has become an integral component of health care systems in many developed countries it has yet to be established in most developing countries. In Lebanon, Palliative care was only recently recognized as a specialty and there are not enough palliative care providers to cover the needs of the population. This article describes the opportunities and barriers to the development of palliative care in the Lebanese context

Role for arthrocentesis in the treatment of temporo-mandibular joint dysfunction

Abstract: The Temporo-mandibular joint [TMJ] is the joint directly in front of the ear on either side of the head where the upper jaw [maxilla] and lower jaw [mandible] meet. This joint is a typical sliding "ball and socket" that has a disc sandwiched between it. The TMJ is used throughout the day to move the jaw, especially in biting and chewing, talking, and yawning. It is one of the most frequently used joints of the body [Beuscher J., 2007]

Patients and Methods: The present study was conducted on 25 patients presented at outpatient clinic of Maxillo-facial Surgery Department. Patients with primary TMD [Intermittent joint pain, joint clicking, and normal mouth opening, MRI showing partial anterior disc displacement with reduction] were selected irrespective of their age and gender

Results: Arthrocentesis was done for 25 patients showing success in 23 patients and failure in 2 patients who required open surgery

Conclusion: Arthrocentesis is the least invasive TMJ surgery. It is also the least expensive. Since it is usually done in the office or in an outpatient clinic. It shows success rate 92% in patients with inclusion criteria

Smoking status effects on common carotid arteries resistivity and pulsatility indices in current Sudanese smokers

Many different indices have been used to describe the shape of the flow waveforms but commonly used indices available on most commercial scanners are: resistance index [RI] and pulsatility index [PI]. This study intended to evaluate the effects of smoking in common carotid arteries Doppler RI and PI, according to smoking status [number of cigarettes smoked per day] in current Sudanese smokers. 1752 Sudanese subjects with 440 of them were non smokers. Female's distribution in the total number of subjects is 161 while males are 1591 with mean age of 28 +/- 11.8 years. a percentage of 49.32% of male subjects were current smokers but there was no female found to be a smoker. Ultrasound examination was established within each vascular laboratory to ensure that common carotid arteries sonography is performed consistently, comprehensively and accurately. These techniques may be modified to match the needs of specific patients or vascular laboratories. In all cases, however, the protocol should meet or exceed the standards established by the American Institute of Ultrasound in Medicine [AIUM] or the Intersocietal Commission for the Accreditation of Vascular Laboratories [ICAVL]. The standards of these two agencies are substantially the same which was our guide for sonographic scanning in the study. Smoking status in current smokers effectively increases the RI and the PI than their normal ranges with a positive linear correlation manner. Findings of this study reported that smoking status effectively increase common carotid arteries Doppler RI and PI in a positive manner were the effect noticed to be in the left common carotid artery more than that of the right one

Primary palliative care: the potential of primary care physicians as providers of palliative care in the community in the Eastern Mediterranean Region

Palliative care focuses on improving the quality of life and relieving suffering in patients with progressive chronic illnesses. Palliative care services remain very limited in the Eastern Mediterranean region although the need for them is high and increasing. The World Health Organization has identified the development of palliative care as a regional priority. This review highlights the urgent need to provide such care in the region and proposes that primary care providers in the region are well placed to provide palliative care in their communities. As palliative medicine is not established as a specialty in the region, training and support in palliative care are required to build capacity in end-of-life care and to allow all patients who would benefit from this approach access to it equitably and early in their illness

Evaluation of thyroid nodules in patients with goitre using nuclear medicine, biopsy and ultrasound in Sudan

Goiter is a common thyroid disorder in Sudan. Most of thyroid nodules are benign, but a small percentage can be cancerous among the other pathology. The aims of this study were to assess the value of scintigraphy, ultrasound [US] and biopsy in the detection of nodules and to determine the prevalence of thyroid nodule among patients with thyroid goiter in Sudan. A total of 100 patients were investigated. 58 patients were investigated with biobsy in addition to the aforementioned techniques. Scintigraphic examination involved the intravenous injection of 2-5 mCi of Tc[99m] followed in 15 minutes by 300 kC at the neck, US was performed using an instruments with a 7.5 MHz and biopsy was carried either by Fine Needle Aspiration Biopsy [FNAB] or open operation. The majority of the patients were females [81%]. Scintigraphy revealed that 58% of the patients had nodular goiter while the rest had diffuse goiter. The highest incidence of nodules was shown in the age group between 40-60 [23%]. US revealed that 48% of the nodules were solitary. Furthermore, 78% the nodules none vascularized, 29% were calcified and 28% were hypoechoic. The biopsy results showed that 14% of nodular patients were malignant, 88% follicular adenocarcinoma. 36% had nodular goiter with cystic or degenerative changes. The highest percentage of malignancy could be attributed to the fact that patients referred to the hospital in a late stage of the disease. All patients with giotre should undergo US and NM investigation in order to detect the morphology and function of the thyroid

Bacterial etiology of pneumonia and acute cerbations of chronic obstructive pulmonary disease at Assiut Unversity Hospital with special refern to carbapenemase

To assess the bacterial etiology of patients hospitalized for pneumonia and acute exacerbations of chronic obstructive pulmonary disease [AECOPD] and for screening and detection of carbapenemases in Enterobacteriaceae. From November 2006 to February 2008, this study was carried out in Assiut University Hospitals. A total of 29lpatients diagnosed as pneumonia and AECOPD [189 pneumonic patients and 102 AECOPD patients] were included in this study. Blood for serology and sputum for culture were obtained from all patients. Serological examination was carried out for detection of atypical bacterial pathogens, using Pneumobact kits [VERCELL Co., Ltd., GRANADA, SPAIN]. Antimicrobial susceptibility testing performed by using the disc diffusion method. Carbapenemase production in Enterobacteriaceae was determined using: disc diffusion method, MICs were determined by an agar dilution technique, imipenem EDTA double discs synergy test and Modfled-Hodge test [confirmatory test]. One hundred and eighty six microorganisms were identified in 165 of pneumonic patients and 98 microorganisms were identified in 93 of AECOPD patients. No organisms could be detected in 24 patients suffering from pneumonia and 9 patients suffering from AECOPD by different cultures or serological techniques. Kiebsiella Pneumoniae was the most common implicated pathogen in patients with pneumonia [34.9% of isolates] and in AECOPD [37.8% of isolates]. In the present study; 55.6% of S. aureus isolates were resistant to methicillin in CAP patients and 61.5% of S. aureus isolates were resistant to methicillin in nosocomial pneumonia [NP] patients. Carbapenemases were detected in 23.86% and 28.5 7% of Enterobacteriaceae of patients with pneumonia and AECOPD respectively. Pneumonia and AECOPD represents a current problem in Assiut University Hospitals. Carbapenemases are among the most important emerging groups of enzymes responsible for antimicrobial resistance. Modified-Hodge test is easy, simple and specific tests for detection of Carbapenemases production

Evaluation of the genotoxicity and pathological changes induced by the prolonged bromuconazole triazole fungicide exposure in rats

Bromuconazole, is a triazole fungicide used in enclosed commercial greenhouses was evaluated for its potential toxic effects in rat liver. Sprague-Dawley male rats were treated orally at daily doses of 36.5 and 18.25 mg/kg b. wt [1/10 and 1/20 LD[50], respectively] Bromuconazole for 3 months. Measurements include potential DNA fingerprinting using random amplified polymorphic DNA [RAPD-PCR] analysis, total nucleic acids content, total protein as well as histopathological alteration in the liver were performed. The results revealed that, Bromuconazole fungicide had genotoxic and toxicopathological effects in rat liver. The genotoxic effects were indicated by appearance of some changes in polymorphism band patterns including deletion of stable bands or insertion of new bands. The effects on the liver were also manifested by different histopathological lesions including severe necrobiotic and proliferative changes with the appearance of hepatoma at high dose. In addition, the liver tissue DNA, RNA and protein contents were significantly increased with increasing the dose of Bromuconazole. Using of Bromuconazole fungicide should be reconsidered due to its possible cytotoxic. clastogenic and mutagenic effects

Histochemical and ultrastructural effects of phytic acid on the mucosa of rat ileum treated with meloxicam

Non-steroidal anti-inflammatory drugs [NSAIDs] cause gastrointestinal damage both in the upper and lower gastrointestinal tract. New anti-inflammatory drugs have been developed in an attempt to improve their gastrointestinal side-effect profile. In spite of the numerous therapeutic advantages of meloxicam, it has, however, damaging effects on the gastrointestinal tract. Inositol hexaphosphate [IP6], also known as phytic acid, is a naturally occurring polyphosphorylated carbohydrate that is particularly abundant in cereals and legumes. It has antioxidant, antimitotic, hypocholesterolemic and hypolipidemic effects. The present study was carried out to evaluate the effect of phytic acid administration on the injurious effects of meloxicam on the mucosa of rat ileum. Thirty albino rats were divided into 3 groups; the first group [control] was put on a normal diet for 4 weeks; the second group received a diet containing 200 mg/kg meloxicam per day for 4 weeks; the third group received a diet containing 200 mg/kg meloxicam per day followed by orally intubated IP6 three times/week for 4 weeks, at a total dose of 40 mg/kg. Slices of ileum of all groups were taken and subjected to histological, histochemical and ultrastructural investigation. The results confirmed the damaging effects of meloxicam on the ileum mucosa and revealed the ameliorative effects of phytic acid against these lesions

Protective effect of zinc against cadmium-induced kidney damage in rats: histological, histochemical and ultrastructural study

The health risks to humans from acute and chronic cadmium [Cd] exposure have been well documented. The kidney is considered the critical organ for Cd toxicity following long-term exposure in humans and experimental animals. There is considerable information in the literature regarding the protective effect of Zn against the cellular toxicity caused by Cd. The present study was undertaken to examine the morphological alterations of the kidney after cadmium exposure, and to evaluate the potential benefit of Zn co-treatment on cadmium-induced tissue injury. Thirty male albino rats were divided into three groups. The first [control] group was injected subcutaneously with normal saline, the second group was injected subcutaneously with cadmium chloride solution [2.5 mg/kg b.w] 5 days/week for six weeks, and the third group was injected with zinc chloride solution [2.2 mg/kg b.w] one hour before the dose of cadmium chloride, 5 days/week for six weeks.Histological, histochemical and ultrastructural investigations of the kidney tissue confirmed the damaging effects of cadmium and revealed the beneficial effects of zinc pre-treatment on Cd-induced structural damage

Efficacy of ovsynch protocol on pregnancy in lactating dairy cattle during summer season

The objective of the present work was to determine the effect of Ovsynch protocol on pregnancy rate in lactating dairy cattle subjected to synchronization of ovulation during summer season.Induction of ovulation for timed artificial insemination [TAT] with Ovsynch protocol was conducted on forty Holstein Friesian cows from a commercial dairy herd in Alexandria disert road [Dina farm],Egypt during the summer season of 2004. Animals were assigned to four groups according to lactation number: G I 1[st]lactation n=13'',G II"2[nd] lactation n=7",G III"3[rd] lactation n=14" and GIV" 4[th] lactation n=6".The mean number of days postpartum [DM] at the start of treatment was 89.38, 77.28, 90.42and 84.66 for group I, II, III and IV, respectively. The frozen-thawed semen used for AI was of good quality. Pregnancy diagnosis was checked by rectal palpation 45 to 55 d after insemination. The pregnancy rate per AI was defined as the percentage of cows that were confirmed pregnant after one AI. High pregnancy rate [50%] was recorded for animals in G IV followed by G H and G HI [42.85%]. Low pregnancy rate [30.7%] was reported in Group I .The overall pregnancy rate was 40% . r From this investigation it could be concluded that synchronization of ovulation with GnRH and PGF2 a provided an effective way to manage reproduction in lactating dairy cattle exposed to heat stress during summer

In vitro production of transgenic tomatoes expressing defensin gene using newly developed regeneration and transformation system

Tomato is considered one of the most important vegetable crops grown in Egypt. Fungal diseases are the most dangerous diseases of tomato on the basis of yield losses. Most previously published procedures for tomato transformation are genotype dependent and still far from routine and universal methods. This study was conducted to enhance regeneration and transformation efficiency of the local Egyptian tomato cultivar [Edkawy]. The developed regeneration system involves the culturing of decapitated seedlings [one cotyledon and a merstimatic shoot tip were removed and the rest of explants include radicals, hypocotyls and one cotyledonary leaf only] on basal MS medium. Multiple shoots per explant were developed after three weeks of cultivation on basal MS medium. The developed system was employed to transfer defensin gene, which renders plants resistance against fungal diseases to the Egyptian cultivar [Edkawy]. Pluronic acid and Agrobacterium concentration were found to be key factors for efficient Agrobacterium-mediated transformation of cultivar [Edkawy]. Transformation was carried out using disarmed A. tumefaciens strain LBA4404 harboring a binary vector pITB-AFP. The plasmid contains defensin gene [AFP] under the control of a CaMV35S promoter and nopaline synthase [NOS] terminator, hygromycin phosphotransferase gene [hpt] and beta-glucuronidase. The modfied developed regeneration/transformation system herein, which orignally rely on flmaingo bill-like explant and floral-dip transformation method, enabled us to produce transgenic tomato shoots without the necessity of a complicated tissue culture system. GUS expression was observed in transformed tomato shoots but never in non-transformed [control]. The possibility of false GUS positives was ruled out because the GUS gene was interrupted by intron. GUS positive explants reacted positively to polymerase chain reaction [PCR] and gave the expected amplicon [300bp] corresponding to AFP gene. The obtained results indicated that the gene of interest was introduced in tomato genome. The results of the present study can be seen as a step towards production of transgenic Egyptian tomtoes resistance to fungal diseases

Thermal stability of Ni [II] and cu [II] mixed ligand complexes derived from biologically important schiff bases, azoles and morpholine

Thermogravimetry [TG] and differential thermogravimefty [DTG] have been applied to the investigation of the thermal behavior of six mixed ligand complexes of Ni[II] and Cu[II] comprising the Schiff bases: o-hydroxyacetophenoneethanolimine [OHAE], N-salicylidene-o-iminophenol [SOP] and N-salicylidene-o-toluidine [SOT] as well as morpholine [Morph] and certain azotes. The azoles used are: 2-amino-thiazole [2-Atz], benzothiazole [Btz], 2-methylbenzothiazole [2-Mbtz], 3-methyl-2-selenoxobenzothiazole [3-Msbtz] and thiabendazole [Tbdz]. Heating the compounds first results in a release of the morpholine or the azoles. Kinetics of the decomposition reactions were studied using non-mechanistic equations

Pattern and severity of rheumatic valvular lesions in children in Khartoum, Sudan

We determined the pattern and severity of valvular involvement in 100 Sudanese patients with rheumatic heart disease [RHD] in 2 centres in Khartoum in 2003. All the patients underwent history taking, physical examination and Doppler echocardiography. The commonest lesions were mitral regurgitation [84%] and aortic regurgitation [40%]. Mitral stenosis alone was uncommon [9%] which could be due to a low detection rate related to the slow stenotic process and the subtle early signs. This, together with the inconsistent history of rheumatic fever, may lead to an underestimate of the prevalence of RHD. There was a strong correlation between severity of the lesion and irregular prophylaxis [P < 0.001]

Immunotoxic effects of lambda-cyhalothrin in rabbits

The effect of Lambda-cyhalothrin on the immune response was studied in rabbits exposed to the insecticide via food at concentrations of 1373.23, 686.76 or 343.38 ppm [equivalent to 1/10[th], 1/20[th] and 1/40[th] oral LD50, respectively] for 8 weeks. The humoral immune response was measured by determination of the antibody titre against sheep red blood cells [SRBC], a T - cell dependent antigen. Moreover, the cell-mediated immune response was evaluated by the delayed - type hypersensitivity reaction to tuberculin. The chemical treatment resulted in a dose - dependent suppression of both humoral and cellmediated immune responses as evidenced by decreased serum hemolysin titres and inhibition of the delayed-type hypersensitivity reaction to tubercluin, respectively. In addition, leucopenia, lymphopenia, depletion of lymphoid cells in the white pulps of spleen, mesentric lymph nodes and Peyer's patches and severe atrophy of thymus cortex were recorded. The serum total protein, albumin, globulin [specially gamma globulin], albumin/globulin [A/G] ratio and the organ to body weight ratios for spleen and thymus were significantly decreased with increasing the insecticide dosage. Moreover, different pathological alterations in liver, and brain were also observed. In conclusion, Lambdacyhalothrin exposure suppressed both humoral and cell-meditated immune responses in rabbits at the tested concentrations in a dose - dependent manner

Effects of aging on pancreatic islet cell function: an experimental immunohistochemical and ultrastructural study

A strong relationship between aging and diabetes mellitus has been clinically suggested, however, none of the previous published data had clearly focused on the age-related cytomorphological changes in the pancreas which are the goal of this study. Three groups of male apparently healthy rabbits have been used, ten animals each; classified as group-1 [3-5months old]; group-2 [9-12 months old] and group-3 [24-36 months old]. After sacrification, sections from the pancreas were stained by Haematoxylin and Eosin [H and E], Gomori trichromic stain and ultrastructurally to detect aging histologic changes as well as immunohistochemically to identify insulin and glucagon secreting cells using their appropriate monoclonal antibodies. A progressive histological distortion with fibrosis and fatty changes were directly proportional to age, being mild in group-2 and severe in group-3. Morphometric studies by computerized image analysis showed that the mean number of islets was significantly higher in group2 [8.98+/-1.51], lowest in group-1 [5.08+/-1.48] and intermediate in group-3 [6.37+/-1.37]. The mean diameter and square area of islets were significantly higher in group-2 compared to other groups [P< 0.05]. The mean number of beta cells per islet and their secretary granules were significantly [P <0.05] higher in group-2, intermediate in group-1 and lowest in group-3.In contrast, the mean number of alpha cells per islet and their secretory granules were insignificantly [P< 0.05] higher in group -2, intermediate in group-3 and lowest in group-1.Also, the beta/alpha ratio [beta cells/alpha cells] was greatest in group-2 [3.059:1], intermediate in group-1 [3.37:1], and lowest in group-3 [2.479:1]. The increased number of beta cells may be due to a compensatory process to correct the hormonal feedback mechanism of insulin .The results of this work suggest that beta cells are generally more vulnerable to aging, an observation which might be correlated clinically with higher incidence of diabetes in older ages

Reactivity of certain biologically important azoles and morpholine towards Ni [II] and Cu [II] complexes of O-hydroxyacetophenoneethanolimine and N-salicylidene derivatives

A number of mixed ligand complexes of Ni [II] and Cu [II] containing the Schiff bases: o-hydroxyacetophenoneethanolimine [OHAE], N-sallicylidene-o-iminophenol [SOP] and N-salicylidene-o-toluidine [SOT] as well as morpholine or the azoles: 2-aminothiazole, benzothiazole and 2-methylbenzothiazole has been prepared and characterized. The IR, UV-VIS spectra and magnetic moment measurements of the complexes were discussed

Pathological and molecular studies on avian leukosis virus subgroup [J] in chicken parents flocks

The present study was carried out on 10 parent chickens flocks collected from different provinces. The examined cases were classified into 47 commercial layers and 198 broiler parents to study the gross and microscopical lesions of different tumors induced by avian leukosis subgroup-J [ALV-J] in broiler breeders and layers flocks. Serological tests were conducted on 245 serum samples to detect the antibodies of ALV-J. Polymerase chain reaction PCR was carried out on tissue samples to confirm the presence of DNA of ALV subgroup J. Myeloid leukosis was recorded in four broiler flocks induced by the novel sub group-J of ALV. Pathological findings of infected parent chickens flocks revealed multiple neoplastic nodules in different organs including liver, kidney, gonads, intestine, skeletal muscle and bone. Histologically, the main constituent of tumor lesions was mature and immature myelocytes. Nephroblastoma was considered as the first recorded cases in Egyptian broiler parent flocks affected with ALV subgroup J. The results of this work concluded that the histopathological examination plays a crucial and decisive role in diagnosing different types of neoplasm caused by avian leukosis virus subgroup-J. The application of PCR test verified the presence of DNA of ALV-J that induced the tumors of myeloid leukosis

effect of pioglitazone on matrix metalloproteinase-9, matrix metalloproteinase-2, tumor necrosis factor-a, vascular endothelial growth factor and E-selectin in skin lesions in psoriatic patients with and without psoriatic arthritis

Psoriasis is a common inflammatory skin disease characterized by infiltration of inflammatory cells into the epidermis and altered keratinocyte differentiation. The aim of the present study was to investigate the role of MMP-9 in the development of psoriasis by assessing the presence of MMP-9 in lesional skin and in sera of psoriatic patients with and without psoriatic arthritis, the association of MMP-9 with the activity of the disease, the relationship between MMP-9 and TNF-alpha production as well as to evaluate the effect of pioglitazone [one of the agents thiazolidinediones] on TNF- alpha, MMP-9, MMP-2, VEGF and E-selectin production and in treatment of psoriasis. Thirty-five psoriatic patients [28 males, 7 females] were included in this study. They were divided into 2 groups. Group I [PsA] included 15 psoriatic patients, clinically presenting joint symptoms associated to the cutaneous disease [PsA]. Group II [Ps] included 20 psoriatic patients, clinically presenting cutaneous disease without psoriatic arthritis [PsA]. Each psoriatic patient received pioglitazone 30 mg/day orally for 10 weeks. Lesional tissue specimens were taken, in the same skin area before and after 10 weeks pioglitazone treatment. Tissues were kept in short term cultures and production soluble mediators such as TNF- alpha, MMP-9, MMP-2, VEGF and E-selectin, which include angiogenic molecules associated to the development of plaque psoriasis, were measured in the culture supernatants by ELISA. MMP-9 concentrations were also measured in the sera. The cutaneous activity of disease was evaluated by the Psoriasis Area and Severity Index [PAST]. Clinical and laboratory assessment indicated that all patients had a significant improvement of the PAS1 score after 10 weeks of pioglitazone therapy. The clinical improvement was associated to a significant decrease of TNF- alpha, MMP-9, MMP-2, VEGFand E-selectin levels [P < 0.05], spontaneously released by lesional biopsies before and after therapy. A significant decrease of MMP-9 [P < 0.01] in the sera, associated to the clinical improvement was also found. In addition, significant positive correlations [P < 0.01] were found between the TNF- alpha and PASI score, MMP-9, MMP-2, VEGFand E-selectin [r = 0.85, 0.84, 0.58, 0.63, 0.67 respectively], as well as between the MMP-9 and PASI, MMP-2, VEGFand E-selectin [r = 0.82, 0.39, 0.69, 0.41 respectively] of patients with PsA after pioglitazone treatment. In psoriatic patients without psoriatic arthritis after pioglitazone treatment there were also significant positive correlations between the TNF- alpha and PASI score, MMP-9, MMP-2, VEGF and E-selectin [r =.0.87, 0.68, 0.53, 0.61, 0.51 respectively], as well as between MMP-9 and PASI, MMP-2, VEGF and E-selectin [r = 0.95, 0.51, 0.58, 0.45 respectively]. The current study shows the existence of a direct relationship between MMP-9 and TNF- alpha production strongly suggesting that MMP-9 may play a key role in the skin inflammatory process. Our findings also demonstrated that pioglitazone could be considered as an efficacious and safe agent for the treatment of psoriasis. The optimum dose and duration of pioglitazone therapy remain to be determined

Thermal decomposition of tetracycline and cephalosporins metal complexes

Thermal behaviour of tetracycline hydrochloride, oxytetracycline dihydrate, Co [II] and Ni [II] complexes of tetracycline and Zn [II] complexes of some cephalosporin antibiotics, namely cephalexin, cephapirin, cefuroxime, and ceftazidime was studied using thermogravimetric analysis [TG]. The TG curves exhibit several thermal events indicating that the thermal decomposition of these compounds are not simple. The kinetic parameters for steps appropriate for kinetic analysis were evaluated making use of the Coats-Redfern equation. During the thermal decomposition of tetracycline hydrochloride anhydro tetracycline was proposed to be formed as an intermediate due to the elimination of water