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N Joshi

Publications and source records attributed to N Joshi.

At least 37 records · Page 2Linked to original sources
PubMed2001

Determination of the ultrastructural pathology of human sperm by atomic force microscopy.

OBJECTIVE: To investigate ultrastructural changes, particularly at the surface, that occur in pathological spermatozoa by using atomic force microscopy (AFM) and to examine the morphological alterations responsible for infertile sperm. DESIGN: Normal fertile and pathological spermatozoa were examined by using a conventional AFM in a noncontact mode. SETTING: Andrology clinic at Los Andes University Hospital. PATIENT(S): Sperm of patients with oligoasthenoteratozoospermia (OAT) and asthenozoospermia were obtained from the Los Andes University Hospital, Mérida, Venezuela. INTERVENTION(S) MAIN OUTCOME MEASURE(S): Morphological details, topological information, and three-dimensional images of the head, neck, and flagellum are presented for both normal and pathological sperm. RESULT(S): The obtained images clearly show dramatic alterations in the morphology of the head, neck, and flagellum of pathological sperm. Even the ultrastructure at the top of the flagellum and the region of the acrosome cap are clearly distinguishable. CONCLUSION(S): This study has significant importance not only for identifying spermatozoa alterations but also for understanding morphological defects and their effects on infertility. If properly exploited, this technique could be an important research tool.

Humans↗
PubMed2001

Poor prognosis of acute stroke patients denied thrombolysis due to early CT findings.

OBJECTIVES: Whether acute stroke patients with major early infarct signs on computed tomography (CT) should be treated with intravenous (i.v.) thrombolysis remains controversial. The authors sought to define the outcomes in 5 consecutive patients who were not treated with i.v. thrombolysis, according to established guidelines. METHODS: The authors retrospectively analyzed the outcomes of a consecutive series of 5 patients evaluated by an acute stroke team at a university medical center and who were denied i.v. tissue plasminogen activator due to early CT changes. RESULTS: Five patients with a median National Institutes of Health Stroke Scale score of 22 (range 20-28) were evaluated. Despite aggressive care (e.g., hemicraniectomy), 2 patients died owing to herniation, 1 patient died of cardiac causes, and neither of the 2 surviving patients achieved a 3-month Rankin score below 4 (moderately severe disability). CONCLUSIONS: Given the poor prognosis of patients with hemispheric stroke and early CT changes, alternative treatment modalities such as intra-arterial thrombolysis, early hemicraniectomy, and neuroprotective therapy should be vigorously pursued.

Acute Disease↗
PubMed2001

Cough in a patient with an infusion port.

In this case report, we describe a patient with a history of fallopian tube adenocarcinoma who had an infusion port in place for the past 4 years. During the course of her stay in the hospital for pneumonia, she developed a cough that became worse with the infusion of fluids through the port. A portogram done to investigate this problem revealed the presence of a portobronchial fistula. This is the first reported case of a portobronchial fistula. Various possibilities to explain the formation of portobronchial fistula are discussed.

Adenocarcinoma↗
PubMed2000

Positive urine nitrite test: an accurate predictor of absence of pure enterococcal bacteriuria.

BACKGROUND: The aim of this study was to determine the potential ability of the urine nitrite test (NT) to predict the class of organism causing urinary tract infection. METHODS: We retrospectively reviewed the records of all adult patients with a positive urine culture over a 6-month period. The infecting microorganisms and the urine NT results were recorded. RESULTS: A total of 729 positive cultures met inclusion criteria. Twenty-one (11%) of the 190 gram-positive organisms and 199 (46%) of the 429 gram-negative organisms yielded a positive NT. Only 5.3% of samples with pure growth of enterococcus yielded a positive NT. The predictive value that a sample yielding a positive NT would show pure growth of enterococcus was low at 2.3%. CONCLUSION: A positive NT is highly predictive of the absence of pure enterococcal bacteriuria.

Adolescent↗
PubMed2000

Comparative study of visceral and parietal pleural biopsy in the etiological diagnosis of pleural diseases.

OBJECTIVE: The present study was planned to evaluate the efficacy and diagnostic reliability of conoctional parietal pleural biopsy to a technique of visceral pleural biopsy. METHOD: Study comprises of 54 diagnosed cases of pleural effusion and after establishing the clinical diagnosis for probable etiological causes. Then parietal pleural biopsy using absents punch biopsy needle and vesceral pleural biopsy using Prabhudesai et al technique was taken in all these patients. Size of the tissue yield; percentage of biopsies; diagnostic yield and sensitivity for these two techniques were compared. RESULTS: A definitive etiological diagnosis could be reached in 52 out of 54 patients on the basis of pleural biopsy (33 tuberculous, 16 malignant and 3 pyogenic), 23 (69.7%) tuberculous effusion patients were diagnosis by visceral pleural biopsy and 14 (42.4%) by parietal pleural biopsy out of 33 diagnosed tuberculous effusion cases. While for the 16 malignant effusions the visceral pleural biopsy showed suggestive histological change in 13 (81.25%) patients and the parietal pleural biopsy in seven (43.8%) with five (31.25%) of these patients being positive by both. All three pyogenic effusions showed only nonspecific inflammatory change in both pleurae. CONCLUSION: The mean size of biopsy sample obtained with modified Prabhudesai et al technique was significantly larger than that of the parietal pleural biopsy with Abrams punch (4.85 mm2 V/s 2.5 mm2 with P < 0.01). Adequate pleural tissue was identifiable in 94.4% and 90.7% of cases, respectively. The modified Prabhudesai et al technique proved to be effective safe and easily learnt. Visceral pleural sampling using this technique is a definite superior addition to the present diagnostic armamentarium of an idiopathic pleural effusion and its routine application together with parietal pleural biopsy will help to establish a definitive diagnosis in majority of patients with idiopathic pleural effusions.

Adolescent↗
PubMed1999

Oral antibiotics: are the old still gold?

Most common infections in ambulatory care can be treated effectively and safely with conventional antibiotics. A rational approach using such antibiotics as primary choices and reserving newer antibiotics for selected, more difficult-to-treat infections will result in substantial cost savings and may help to prevent the rapid development of drug resistance.

Anti-Infective Agents↗
PubMed1999

Activated protein C resistance in young African American patients with ischemic stroke.

BACKGROUND: It has been proposed that activated protein C resistance (APCR) due to the factor V Leiden (FVL) mutation may be a risk factor for stroke in young adults. However, this may not be the case for all ethnic groups due to variability in the prevalence of the FVL mutation. METHODS: Case series from a university neurology clinic. Patients with an APCR ratio of 2.2 or below were tested for the FVL mutation (nine patients). Patients on warfarin were also tested for the FVL mutation (14 patients). RESULTS: 38 African American patients under age 55 with an arterial stroke were identified. The mean age of the patients is 43.1 years. Five percent had an APCR ratio of 2.0 or below. None of the patients with an APCR ratio of 2.2 or below or the patients directly tested for the FVL mutation had the mutant allele. CONCLUSIONS: Activated protein C resistance due to the FVL mutation does not appear to be a major risk factor for stroke in young African Americans. Other, as yet unidentified, mechanisms leading to activated protein C resistance may be important in a small subset of young African American stroke patients.

Activated Protein C Resistance↗
PubMed1999

Intersubject variability and intrasubject reproducibility of the bereitschaftspotential.

We assessed the intersubject variability and intrasubject reproducibility of the bereitschaftspotential (BP). Twenty healthy volunteers performed extensions of their wrist in a self-paced manner every 5-10 seconds. A surface electromyography (EMG) electrode was attached to the wrist extensor group of the dominant hand to record at least 100 wrist movements, and electroencephalography electrodes were placed over the scalp. Trials were performed at baseline, 15 minutes, 4 hours, and 4 weeks. Measures derived from the BP included area 1 (-2000 to -650 msec), area 2 (-650-0 msec), total area (area 1 + area 2), amplitude at -650 msec, amplitude at peak negativity prior to EMG onset, and amplitude at 0 msec (trigger). Our findings revealed different variability/reproducibility depending on the particular BP measure being analyzed. Using intraclass correlation coefficient (ICC) and concordance correlation coefficient (CCC) as measures of intrasubject reproducibility, area 2, amplitude at peak negativity prior to EMG onset, and amplitude at 0 msec produced the best values. We conclude that in studies that attempt to quantify BP changes before and after an intervention in the same group of subjects, the most reproducible BP measures are those pertaining to the late BP component.

Adolescent↗
PubMed1999

The third heart sound.

BACKGROUND: In the current era of cost-effective delivery of health care, it is particularly timely to carefully reevaluate the clinical utility of selected physical signs. The third heart sound (S3) is one such sign that is the focus of the current review. METHODS: I conducted a computerized MEDLINE search of articles related to S3 published since 1966. For information before 1966, textbook and other cross-references from MEDLINE-identified sources were used. RESULTS: The presence of S3 may be the earliest clue to the presence of left ventricular failure. It predicts a high risk of postoperative complications in the setting of noncardiac surgery and is a predictor of response to digoxin in patients with congestive heart failure. However, the interobserver variation in its detection is high even among experienced clinicians. CONCLUSIONS: While the presence of S3 may have important clinical implications, high interobserver variation in detection limits its use.

Adult↗
PubMed1999

Mechanisms of retinal arterial occlusive disease in African American and Caucasian patients.

BACKGROUND AND PURPOSE: The aim of our study was to evaluate the causes of retinal arterial occlusive disease in African American patients and to compare these etiologies with those observed in Caucasian patients with retinal ischemic symptoms. METHODS: We performed a retrospective analysis of a series of consecutive patients evaluated by both the ophthalmology department and the neurology/stroke clinic. Patients had a diagnosis of amaurosis fugax, branch retinal artery occlusion, central retinal artery occlusion, or intra-arterial retinal plaques. RESULTS: Twenty-nine African American patients and 17 Caucasian patients were evaluated. African American patients had a mean age of 61 years (range, 30 to 77 years) and Caucasian patients a mean age of 73 years (range, 56 to 94 years) (P=0.003). There was no statistically significant difference between the 2 groups with respect to visible emboli on funduscopy (P=0.462). After adjusting for age, there was also no difference between the 2 groups with regards to risk factors for arterial occlusive disease such as hypertension, coronary artery disease, hypercholesterolemia, tobacco use, and history of stroke or transient ischemic attacks. Caucasian patients had a 41% incidence (7/17) of high-grade ipsilateral internal carotid artery stenosis, measured by carotid duplex, compared with 3.4% incidence (1/29) in African American patients (P=0.002). CONCLUSIONS: There are racial differences in the causes of retinal arterial occlusion. African American patients have a low prevalence of moderate to severe extracranial carotid stenosis, and a high proportion of African American patients have cryptogenic retinal ischemia. In Caucasian patients there is a stronger association between extracranial carotid artery disease and retinal arterial occlusion.

Adult↗
PubMed1998

Phase shift magnitude and direction determine whether Siberian hamsters reentrain to the photocycle.

Body temperature (Tb) or activity rhythms were monitored in male Siberian hamsters (Phodopus sungorus) housed in an LD cycle of 16 h light/day from birth. At 3 months of age, rhythms were monitored for 14 days, and then the LD cycle was phase delayed by 1, 3, or 5 h or phase advanced by 5 h in four separate groups of animals. Phase delays were accomplished via a 1- or 3-h extension of the light phase or via a 5-h extension of the dark phase. The phase advance was accomplished via a 5-h shortening of the light phase. After 2 to 3 weeks, hamsters that were phase delayed by 1 or 3 h were then phase advanced by 1 or 3 h, respectively, via a shortening of the light phase. All of the animals reentrained to phase delays of 1 or 3 h and to a 1-h phase advance; 79% reentrained to a 3-h phase advance. In contrast, only 13% of the animals reentrained to the 5-h phase advance, 13% became arrhythmic, and 74% free ran for several weeks. After the 5-h phase delay, however, reentrainment was observed in 50% of the animals although half of them required more than 21 days to reentrain. The response to a phase shift could not be predicted by any parameter of circadian rhythm organization assessed prior to the phase shift. These data demonstrate that a phase shift of the LD cycle can permanently disrupt entrainment mechanisms and eliminate circadian Tb and activity rhythms. Magnitude and direction of a phase shift of the LD cycle determine not only the rate but also the probability of reentrainment. Furthermore, the phase of the LD cycle at which the phase shift is made has a marked effect on the proportion of animals that reentrain. Light exposure during mid-subjective night combined with daily light exposure during the active phase may explain these phenomena.

Animals↗
PubMed1998

Clinical safety and efficacy of first indigenous recombinant hepatitis B vaccine.

A pilot study was conducted to assess the clinical safety and immunogenicity of an indigenously developed recombinant hepatitis B vaccine (Shanvac B) in 18 healthy adults. 20 microg of vaccine was administered at 0, 1 and 2 months. Protective anti HBs titres developed in 22%, 77% and 100% one month after 1st, 2nd and 3rd dose of vaccination, respectively. The geometric mean titre after the 3rd dose was 1015.29 mIu/ml. The vaccine was well tolerated with minor local and systemic side effects in 28% and 22%, respectively. The indigenously developed recombinant hepatitis B vaccine is safe, well tolerated and highly immunogenic.

Adolescent↗
PubMed1998

Papillary carcinoma of the male breast diagnosed by fine needle aspiration cytology.

A 57-year old male presented with a left breast mass, the fine needle aspiration cytology revealed characteristic cytomorphological features of papillary carcinoma of the breast. In our knowledge this is a second reported case of papillary carcinoma of male breast diagnosed by the fine needle aspiration cytology. Cytomorphological and histopathological features of the case are described with literature on cytological features of papillary carcinoma and carcinoma of male breast is briefly reviewed.

Biopsy, Needle↗
PubMed1998

Oral rehabilitation in dentinogenesis imperfecta with overdentures: case report.

A seventeen-year-old girl demonstrating severely worn permanent dentition and multiple retained root stumps with dentinogenesis imperfecta is presented. Overdentures were made to preserve bone height, re-establish the lost vertical dimension of occlusion, to provide acceptable esthetics, and to establish an efficient masticatory system.

Adolescent↗