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Biomedical subjects

S Krishnamurthy

Publications and source records attributed to S Krishnamurthy.

At least 73 records · Page 4Linked to original sources
PubMed1993

The effects of ventilator working pressure during pressure support ventilation.

The purpose of this study was to examine the consequences of altering ventilator working pressure on airway pressure and flow characteristics during pressure support ventilation (PSV). A ventilator (Siemens Servo 900C) and single lung simulator were used, and graphic read outs, in triplicate, were taken at a variety of combinations of PSV, working pressure, lung compliance, and airway resistance. The graphic read outs were then analyzed for a number of "dependent variables," and multiple regression analyses were performed using working pressure, PSV level, compliance, and resistance as "independent variables." The results show that the relative impact of working pressure on airway pressure and flow will vary with other lung and airway characteristics; also, excessive working pressure results in significantly greater flow rates at 40 ms after onset of inspiratory flow and at maximum flow, greater ringing or overshoot in the circuit, reduced tidal volume and inspiratory time, and reduced area under the airway pressure curve. In conclusion, adjusting ventilator working pressure will significantly affect lung-ventilator interaction in a quantifiable fashion. Further, these findings support clinical evidence that working pressure and/or initial flow rate need to be individualized to ensure optimal airway flow and pressure characteristics.

Airway Resistance↗
PubMed1993

Maxillary extragonadal germ cell tumor: a case report.

A single case report of a patient with primary extragonadal endodermal sinus tumor affecting the maxillary region is reported here. The patient was treated with combination chemotherapy consisting of bleomycin, cisplatin and etoposide. The child achieved complete remission and is now disease free for three years.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Ascorbate-dependent formation of hydroxyl radicals in the presence of iron chelates.

The autoxidation of L-ascorbate on incubation in saline phosphate buffer (pH 7.4) is accompanied by hydroxyl radical (.OH) generation. The metal chelator EDTA showed significant inhibition of ascorbate autoxidation and ascorbate-dependent .OH release. On the other hand, Fe2+ (EDTA) greatly augmented both ascorbate autoxidation and ascorbate-dependent .OH production. The biological iron chelating compounds such as ATP, ADP, citrate and pyrophosphate suppressed both ascorbate autoxidation and ascorbate-mediated .OH production, thereby indicating that these compounds suppress the activating effect of iron. Ascorbate autoxidation and ascorbate-dependent .OH formation, stimulated by Fe2+ (EDTA) were significantly inhibited by .OH scavengers, namely mannitol, thiourea and sodium formate, as well as by catalase and to a lesser extent by bovine serum albumin, superoxide dismutase (native and heat denatured) and heat denatured catalase.

Adenosine Diphosphate↗
PubMed1993

Unusual bone metastasis as the initial symptom of gastric cancer--a report of four cases.

Four cases of gastric cancer presenting with bone pain due to metastasis as the initial symptom are reported. Investigations revealed solitary osteolytic metastasis in the mandible in one, and left scapula in one patient. Third patient had multiple osteosclerotic metastasis with elevation of acid phosphatase and another had multiple discrete osteolytic metastasis simulating multiple myeloma. All the primary gastric cancers were poorly differentiated adenocarcinoma and three were of Borrman type III on gross appearance. One patient had sparing of the liver inspite of extensive metastasis. Chemotherapy was in effective in two patients and the prognosis was uniformly poor.

Adult↗
PubMed1993

Glycemic response and lipemic index of rice, raggi and tapioca as compared to wheat diet in human.

Carbohydrate rich diet, rice, raggi or tapioca given to individuals of both sexes for 15 days did not alter the glycemic response (after oral glucose loading) as compared to an isocaloric wheat basal back ground diet. However, plasma cholesterol profile was reduced significantly by raggi and tapioca. Raggi reduced total serum cholesterol; low density lipoprotein cholesterol by 9% each, triglycerides by 15% and increased high density lipoprotein cholesterol, showing a significant beneficial effect on plasma cholesterol profile. Lipemic index as introduced in the present study was 121, 57 and 55 for rice, tapioca and raggi respectively when base line value of the isocaloric wheat supplemented back ground diet (control) was taken as 100.

Adult↗
PubMed1992

The geography of non-ocular malignant melanoma in India: its association with latitude, ozone levels and UV light exposure.

Ultraviolet light from sunlight is implicated in the aetiology of non-ocular malignant melanoma, mostly from Western studies. This study reports the relation of such melanomas from 7 cancer registries in different parts of India with latitude, altitude, ozone levels and ultraviolet (UV) light exposure. A log linear model was fitted using GLIM, assuming Poisson errors in incidence; linear and non-linear regression techniques were also used. Results show slight negative associations of melanoma with latitude, chi 2 = -3.37, p = 0.07, and statistically non-significant ones with atmospheric ozone levels (r = -0.36, n.s.), and a positive association with UV (r = 0.30, n.s.). Melanoma incidence from 4 places relates in a parabolic curve with latitude (y = 1-0.09 chi 2 + 0.003 chi 2 in males and y = 1.73-0.17 chi 2 + 0.005 chi 2 in females). Patients originally from west coastal ethnic/linguistic communities predominate in Bombay. Geographic patterns of melanoma in Indians are similar with those in white Caucasians. Ultraviolet light exposure may also be involved in its aetiology in non-white Caucasians, such as Indians.

Atmosphere↗
PubMed1992

Dermatofibrosarcoma protuberans metastatic to the lung. A case report.

A case is presented of dermatofibrosarcoma protuberans of the gluteal region with metastasis to the lung appearing 7 years after wide excision of the primary lesion. The world literature is reviewed. The clinical and pathologic features of dermatofibrosarcoma are reviewed and treatment is discussed, with the aim of emphasizing the need for long-term follow-up examination of lymph nodes and for metastases following wide excision of these lesions.

Adult↗
PubMed1992

Immunological changes in normal pregnancy.

During pregnancy the mother must tolerate intra-uterine allogenic fetal tissue. Failure of this tolerance may cause spontaneous abortion. The immunological changes occurring in normal pregnancy are poorly understood. The aim of this study was to investigate the immunological changes occurring in pregnancy. Thirty women in the first trimester; 10 in the second and 10 in the third trimester of pregnancy were studied and compared to age matched non-pregnant controls. In normal pregnancy there was an increase in the total white cell count with no change in the lymphocyte count. There was a fall in total T cell numbers and activated T cell numbers, with no change in helper/inducer or suppressor/cytotoxic T cell numbers. [3H]Thymidine uptake in response to three different mitogens was increased. This implies an increase in potential for the cells to respond to mitogens. There was no change in interleukin-2 receptor levels, suggesting that despite this increased potential there was no general activation of the immune system. A rise in IgM and IgG was found after mitogen stimulation of peripheral blood lymphocytes, suggesting an increase in potential antibody production. These results demonstrate that lymphocytes from pregnant women have an increased potential rather than an increased activity.

Female↗
PubMed1992

Cystic neoplasms of the pancreas: a heterogeneous disorder.

Cystic neoplasms of the pancreas are rare tumors with a relatively better prognosis as compared to other pancreatic cancers. They may be mistaken for pseudocysts. Seventeen patients who underwent surgical resection were analyzed. Seventy percent of the patients were females and 76.7% of the tumors were located in the tail of the pancreas. Preoperative diagnosis was made on the basis of ultrasonography and/or computed tomography findings in 60% of patients. Retrospective review of the imaging modalities revealed one or more findings suggestive of cystic neoplasms in 90% of the patients. These included multiloculated cysts, thickened cyst wall, intracystic mass or calcifications, and presence of liver metastasis. All the tumors were completely or partly excised. The final histopathological diagnosis was microcystic adenoma in 2, mucinous cyst adenoma in 1, papillary cystic neoplasm in 3, cystic neuroendocrine tumor in 5, and cystadenocarcinoma in 6. Of the 17 patients, 10 had malignant tumors. Seven patients with benign tumors and 3 patients with malignant tumors are disease free 12-30 months after resection. Cystic neoplasm must always be considered as a possibility when dealing with cystic lesions of the pancreas and a careful evaluation of ultrasonography and computed tomographic scan may give a clue to the diagnosis.

Adolescent↗
PubMed1992

Glycemic index of selected foodstuffs commonly used in south India.

To assess the true physiological basis of carbohydrate exchange of food, commonly eaten in South India, the "Glycemic Index", defined as the area of the glucose tolerance test, under 3 hr, for each food item, expressed as percentage of the area after taking the same amount of carbohydrate as glucose (75 gms) was studied, in healthy fasting human volunteers. Thirteen articles of food items were fed to groups of 12 to 15 healthy fasting volunteers and their glucose tolerance test values up to 3 hr, were measured. The highest glycemic index values were shown by starchy tubers, Raggi and fleshy fruits, while relatively lower values were obtained for pulses and rice; whole wheat showed the smallest glycemic index.

Adult↗
PubMed1991

Cancer and other causes of childhood mortality in Bombay, India.

Mortality from cancer and other diseases from 1964 to 1984 and their contributions in 1984 to premature mortality in Bombay, India, were studied. Cancer was the ninth and tenth cause of death in boys and girls younger than 15 years of age, respectively, in 1984. Prematurity and infectious diseases contributed most to years of potential life lost by children younger than 5 years of age in 1984; cancer, heart disease, and accidents-injury became important in children older than 5 years. When currently high mortality rates in infants and children younger than 5 years of age are reduced, cancer may become a greater childhood health problem. Approximately 5% of male and 3% of female patients with cancer in six hospital and three population-based cancer registries in India were children younger than 15 years of age. Cancer mortality declined from the rate during 1964 to 1972 to the rate during 1973 to 1984 by about 40% in children younger than 5 years old and in girls of 10 to 14 years of age and by 7.5% and 14% in the 5 to 9-year-old boys and girls, respectively. It increased by 12% in the 10 to 14-year-old boys. Early diagnosis and treatment of cancer in children older than 5 years of age may yield increased productive person-years of life.

Cause of Death↗
PubMed1991

Changes in immunologic parameters in normal pregnancy and spontaneous abortion.

To study the immunologic characteristics of miscarriage, 40 nonpregnant control subjects, 40 primigravid women in the first trimester of pregnancy, and 18 patients admitted with a spontaneous abortion were investigated. The total white blood cell count was raised significantly in normal pregnancy and spontaneous abortion (p less than 0.0005). The lymphocyte count was unchanged. The total T-cell number fell significantly in normal pregnancy and abortion (p less than 0.01). No change was seen in the cytotoxic suppressor or helper/inducer T-cell numbers. The number of activated T cells fell significantly in both groups of patients (p less than 0.0005). The response to mitogens was greatly increased in both normal patients and those with miscarriage. A marked rise in interleukin-2 receptor levels was noted in patients with spontaneous abortion (p less than 0.005). The changes in white blood cell count, total T-cell number, activated T-cell number, and mitogen activity were thought to be a direct result of pregnancy. The rise in interleukin-2 receptor levels was seen only in the miscarriage group. Although it is not known if these changes are cause or effect, it would appear that immunologic abnormalities are associated with spontaneous abortion.

Abortion, Spontaneous↗
PubMed1991

Technetium-99m monoclonal antibody fragment (Fab) scintigraphy in the evaluation of small cell lung cancer: a preliminary report.

Small cell lung cancer (SCC) has the most rapid growth rate of the four cell types and metastasizes early. Present imaging modalities for staging include chest x-ray, CT, MRI and bone scans. In this preliminary study, we assessed the clinical role of 99mTc-monoclonal antibody (MOAB) scintigraphy in five patients with histologically proven SCC. Each patient was infused with 20-30 mCi of 99mTc labeled Fab fragment of MOAB (NR-LU-10, NeoRx, Seattle, Wash.). Total body simultaneous anterior and posterior images were obtained 14-16 h post injection. SPECT images of the chest were obtained through a 360 degrees rotation of the gamma camera and recorded on a 62 x 64 x 16 matrix. Images (1.2 cm thick) were generated in transaxial, sagittal and coronal views. Fourteen of fifteen chest lesions detected by CT were confirmed by 99mTc MOAB scintigraphy. Scintigraphy detected one additional chest lesion not seen by CT. Scintigraphy failed to detect a brain lesion (2 cm), a chest lesion, and two adrenal lesions, all of which were seen by CT. In one patient with multiple (more than 10) lesions in the liver, both scintigraphy and CT detected all lesions. Three spine lesions seen on 99mTc MDP scan and positive for metastasis on MRI concentrated 99mTc MOAB, but two rib lesions seen on 99mTc MDP bone scan did not concentrate 99mTc MOAB. It is concluded from these preliminary results that the potential usefulness of 99mTc MOAB scintigraphy as a complementary imaging modality in the staging of small cell lung cancer should be investigated further.

Bone Marrow↗
PubMed1991

The role of postnatal x-ray pelvimetry after caesarean section in the management of subsequent delivery.

The purpose of this study was to investigate the influence of postnatal x-ray pelvimetry after caesarean section on the management of the subsequent pregnancy. The case records of 331 women delivered by casearean section in their first pregnancy were reviewed. By standard radiological criteria, the pelvis was considered to be inadequate in 248 (75%) of them and adequate in 83 (25%). Of the women with a radiologically inadequate pelvis, 172 underwent an elective caesarean section. Seventy-six were allowed vaginal delivery: 51 of these women delivered vaginally and 25 required an emergency caesarean section. Of the women with a radiologically adequate pelvis, 61 achieved a vaginal delivery and 22 were delivered by caesarean section. All of the three cases of uterine rupture occurred in women with a radiologically adequate pelvis. This study suggests that x-ray pelvimetry is not a good predictor of the outcome of a trial of vaginal delivery. We conclude that the practice of routine postnatal pelvimetry should be abandoned.

Birth Weight↗