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C Bal

Publications and source records attributed to C Bal.

25 records · Page 2Linked to original sources
PubMed1996

Characterization of beta-lactamase gene blaPER-2, which encodes an extended-spectrum class A beta-lactamase.

Plasmidic extended-spectrum beta-lactamases of Ambler class A are mostly inactive against ceftibuten. Salmonella typhimurium JMC isolated in Argentina harbors a bla gene located on a plasmid (pMVP-5) which confers transferable resistance to oxyiminocephalosporins, aztreonam, and ceftibuten. The beta-lactamase PER-2 (formerly ceftibutenase-1; CTI-1) is highly susceptible to inhibition by clavulanate and is located at a pI of 5.4 after isoelectric focusing. The blaPER-2 gene was cloned and sequenced. The nucleotide sequence of a 2.2-kb insert in vector pBluescript includes an open reading frame of 927 bp. Comparison of the deduced amino acid sequence of PER-2 with those of other beta-lactamases indicates that PER-2 is not closely related to TEM or SHV enzymes (25 to 26% homology). PER-2 is most closely related to PER-1 (86.4% homology), an Ambler class A enzyme first detected in Pseudomonas aeruginosa. An enzyme with an amino acid sequence identical to that of PER-1, meanwhile, was found in various members of the family Enterobacteriaceae isolated from patients in Turkey. Our data indicate that PER-2 and PER-1 represent a new group of Ambler class A extended-spectrum beta-lactamases. PER-2 so far has been detected only in pathogens (S. typhimurium, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis) isolated from patients in South America, while the incidence of PER-1-producing strains so far has been restricted to Turkey, where it occurs both in members of the family Enterobacteriaceae and in P. aeruginosa.

Amino Acid Sequence↗
PubMed1995

Effect of endoscopic variceal sclerotherapy on esophageal motor functions and gastroesophageal reflux.

UNLABELLED: Sclerotherapy results in significant local complications, both immediate and delayed. This study was designed to examine the esophageal pathophysiology underlying these complications. METHODS: We prospectively evaluated esophageal transit, motility abnormalities and gastroesophageal reflux (GER) with barium studies and esophageal functional scintigraphy in 24 patients (20 men, 4 women; mean age 33 +/- 12.4 yr) before sclerotherapy (Phase I), after two sessions (Phase II), following variceal eradication (Phase III) and 4 wk later (Phase IV). RESULTS: Varices were obliterated after 5.6 +/- 1.9 sessions of intravariceal sclerotherapy performed weekly with 1% polidocanol (17.3 ml per session). There was no baseline Phase I dysmotility or reflux. Phase II studies recorded a marked delay of esophageal global and segmental (mid and distal) transit time in 98.2% of patients by scintigraphy and 90% by barium studies. Incoordinate contractions and aperistalsis were observed in 0, 66.7%, 58.3% and 33.8% of patients from Phases I-IV studies, respectively. Barium studies revealed tertiary waves and reverse peristalsis in 0, 50%, and 75% of patients from Phases I-III; strictures were observed in 0, 1, and 3 patients during Phases I-III. GER was detected scintigraphically in 0, 58.3%, 25% and 16.6% during Phases I-IV sequentially. In contrast, barium studies grossly underestimated GER (0, 5% and 15% at phases I-III). CONCLUSION: There was strong concordance between esophageal symptoms, transit, motility abnormalities and GER (p < 0.05). Variceal eradication (Phases III and IV) was associated with a gradual recovery of esophageal symptoms, ulcers and all abnormal scintigraphic parameters. Sclerosant-induced chemical esophagitis in association with peptic esophagitis due to gross reflux following sclerotherapy possibly can explain the symptoms in most patients.

Adult↗
PubMed1995

Technetium-99m-HMPAO SPECT cerebral blood flow study in children with craniosynostosis.

UNLABELLED: Premature closure of cranial sutures (primary craniosynostosis) in children leads to characteristic skull deformities and prevents the constricted brain from growing normally. Although the cause remains unknown, several etiological factors have been cited. Recently, hypovascularity has been reported as a possible cause of craniosynostosis. METHODS: In a prospective study regional cerebral blood flow studies were carried out with 99mTc-HMPAO SPECT in seven children with craniosynostoses. Five preoperative and six postoperative studies were conducted and the results correlated with radiological and surgical findings. RESULTS: Preoperative studies revealed regional hypovascularity in the underlying cerebral hemisphere, corresponding to the fused sutures. Postoperative studies revealed disappearance of these perfusion defects in most cases, indicating normalization of perfusion following surgical decompression. CONCLUSION: This study establishes the presence of cerebral hypovascularity in craniosynostoses and suggests that early surgery and release of craniostenosis is essential to achieve optimum perfusion and brain development.

Brain↗
PubMed1993

"Insular" carcinoma of thyroid. A subset of anaplastic thyroid malignancy with a less aggressive clinical course.

Insular carcinoma of the thyroid appears to represent an entity situated morphologically and biologically in an intermediate position between the well-differentiated and undifferentiated (anaplastic) tumors. The retention of I-131 concentrating ability by this variant, unlike anaplastic, is very encouraging and amenable to detection and therapy by radioiodine after initial aggressive surgery. A 46-year-old man with a histologic label of anaplastic thyroid carcinoma has had an unusually prolonged disease-free survival and histopathologic review confirmed insular carcinoma. Postoperative radioiodine evaluation revealed avid concentration of tracer in the thyroid bed. Thus, it is possible to ablate with radioiodine. The insular carcinoma should be considered as a distinct clinicopathologic entity and widespread awareness of this variant of tumor may help pathologists, surgeons, and nuclear medicine practitioners to aggressively treat the condition after initial diagnosis.

Carcinoma↗
PubMed1990

The therapeutic efficacy of oral cholecystographic agent (iopanoic acid) in the management of hyperthyroidism.

Five randomly chosen patients with thyrotoxicosis were administered 1 gm of the oral cholecystographic agent iopanoic acid daily for 21 days. There was a marked fall in T3 levels by 75% of the pretherapy value by 96 hr; values remained normal over the 21-day period. T4 values fell significantly by seven days of therapy, and the decreased values were sustained. FT3 and FT4I also showed corresponding decreases in value. All subjects showed clinical improvement by both subjective and objective criteria. During therapy, escape from the effect of iopanoic acid was not encountered. However, after stopping the drug for 2-4 wk, the patients' iodine-131 uptake become as high as the pretherapy level, enabling them to undergo radioiodine treatment for thyrotoxicosis. The treatment strategy can be aimed at achieving quick euthyroidism and in planning radioiodine treatment as early as possible in high risk patients. This treatment may also be useful in preoperative control of thyrotoxicosis.

Administration, Oral↗
PubMedDate not supplied

Samarium-153 ethylenediamine tetramethylene phosphonate therapy for bone pain palliation in skeletal metastases.

BACKGROUND: Systemic therapy with radionuclides may be used for the treatment of patients with painful skeletal metastases owing to its efficacy, low cost and low toxicity. Imported radionuclides for pain palliation, like Strontium-89 are expensive; particularly for developing countries. In the Indian scenario, Samarium-153 (Sm-153) is produced in our own reactors and as a result, it is readily available and economical. AIM: We undertook this study to determine the efficacy and toxicity of single-dose Sm-153 ethylenediamine tetramethylene phosphonate as a palliative treatment for painful skeletal metastases. MATERIALS AND METHODS: Eightysix patients with painful skeletal metastases from various primaries, were treated with Sm-153 EDTMP at a dose of 37 MBq/kg. The effects were evaluated according to change in visual analogue pain score, analgesic consumption, Karnofsky performance score, mobility score and blood count tests, conducted regularly for 16 weeks. STATISTICS: Repeated measures analysis. RESULTS: The overall response rates were 73%, while complete response was seen in 12.4%. Reduction in analgesic consumption with improvement in Karnofsky performance score and mobility score, was seen in all responders. Response rates were 80.3 and 80.5% in breast and prostate cancer, respectively. One case, each of Wilms tumor, ovarian cancer, germ cell tumor testis, multiple myeloma, primitive neuroectodermal tumor and oesophageal cancer, did not respond to therapy. No serious side-effects were noted, except for fall in white blood cell, platelet and haemoglobin counts, which gradually returned to normal levels by six-eight weeks. CONCLUSION: Sm-153 EDTMP provided effective palliation in 73% patients with painful bone metastases: the major toxicity was temporary myelosuppression.

Adolescent↗