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Biomedical subjects

S A Syed

Publications and source records attributed to S A Syed.

At least 37 records · Page 2Linked to original sources
PubMed1994

A transverse skin incision approach for decompression of pronator teres syndrome.

Pronator teres syndrome is a compressive neuropathy of the median nerve in the proximal part of the forearm and distal part of the arm. The outcome of surgical decompression is occasionally unsatisfactory because of a poor scar. We present the use of a transverse skin incision that allows adequate exploration and decompression distally and proximally, beneath the subcutaneous tissue beyond the volar elbow crease.

Adult↗
PubMed1994

Comparison of proximal and distal one portal entry techniques for endoscopic carpal tunnel release. A cadaver study.

Reported complications of endoscopic carpal tunnel release have increased as more surgeons use this technique to release the flexor retinaculum. We used a cadaver model to compare the results of endoscopic carpal tunnel release through a one-portal distal (Group A, 15 specimens) and a one-portal proximal (Group B, 15 specimens) entry site with a new endoscopic technique. Our custom-made glass tube of three different sizes (5, 7, and 9 mm in diameter) is designed to house an endoscope and accommodate a meniscus knife for releasing the flexor retinaculum. Complete release of the flexor retinaculum was obtained in all limbs in both groups. In Group A the one complication (7%) was loss of the cotton tip from the cotton swab stick within the carpal tunnel. In Group B, there was a single case of injury to the superficial palmar arch in one hand and breakage of a glass tube in another hand, for a total complication rate of 13%. No other damage to anatomical structures was noted.

Cadaver↗
PubMed1994

A comparison of periodontal disease among rural Amish and non-Amish adults.

Periodontal disease can be more efficiently studied within a homogeneous population where genetic influences and lifestyles are similar enough to negative their effect on the disease process. This study focuses on an Amish population in southern Michigan who isolate themselves from outside influences and their non-Amish neighbors. A total of 425 Amish and 290 non-Amish were contacted resulting in 330 Amish and 215 non-Amish who were examined in their homes giving a participation rate of 76.2%. Ages ranged from 18 to 82 years. Prevalence of periodontal disease tended to be higher among males and increased with age. There were slightly more Amish females (52%) than non-Amish (49%). Means of periodontal conditions for Amish were 1.35 mm for attachment loss, 2.59 mm for pocket depth, 0.24 for calculus, 0.77 for plaque and 0.74 for gingivitis. For non-Amish, the means were 1.03 mm for attachment loss, 2.38 mm for pocket depth, 0.40 for calculus, 0.95 for plaque and 0.87 for gingivitis. It is of interest that the Amish do not practice routine oral hygiene. Only 36.8% of Amish reported brushing at least 1 x a day compared to 84.6% of non-Amish. Similarly, only 8.2% of Amish reported flossing at least 1 x a week compared to 40.8% of non-Amish.

Adolescent↗
PubMed1994

An endo-acting proline-specific oligopeptidase from Treponema denticola ATCC 35405: evidence of hydrolysis of human bioactive peptides.

An endo-acting proline-specific oligopeptidase (prolyl oligopeptidase [POPase], EC 3.4.21.26) was purified to homogeneity from the Triton X-100 extracts of cells of Treponema denticola ATCC 35405 (a human oral spirochete) by a procedure that comprised five successive fast protein liquid chromatography steps. The POPase is a cell-associated 75- to 77-kDa protein with an isoelectric point of ca. 6.5. The enzyme hydrolyzed (optimum pH 6.5) the Pro-pNA bond in carbobenzoxy-Gly-Pro-p-nitroanilide (Z-Gly-Pro-pNA) and bonds at the carboxyl side of proline in several human bioactive peptides, such as bradykinin, substance P, neurotensin, angiotensins, oxytocin, vasopressin, and human endothelin fragment 22-38. The minimum hydrolyzable peptide size was tetrapeptide P3P2P1P'1, while the maximum substrate size was ca. 3 kDa. An imino acid residue in position P1 was absolutely necessary. The hydrolysis of Z-Gly-Pro-pNA was potently inhibited by the following, with the Ki(app) (in micromolar) in parentheses: insulin B-chain (0.7), human endothelin-1 (0.5), neuropeptide Y (1.7), substance P (32.0), T-kinin (4.0), neurotensin (5.0), and bradykinin (16.0). Chemical modification and inhibition studies suggest that the POPase is a serine endopeptidase whose activity depends on the catalytic triad of COOH ... Ser ... His but not on a metal. The amino acid sequence around the putative active-site serine is Gly-Gly-Ser-Asn-Pro-Gly. The enzyme is suggested to contain a reactive cysteinyl residue near the active site. Amino acid residues 4 to 24 of the first 24 N-terminal residues showed a homology of 71% with the POPase precursor from Flavobacterium meningosepticum and considerable homology with the Aeromonas hydrophila POPase. The ready hydrolysis of human bioactive peptides at bonds involving an imino acid residue suggests that enzymes like POPase may contribute to the chronicity of periodontal infections by participating in the peptidolytic processing of those peptides.

Amino Acid Sequence↗
PubMed1993

Proteolytic and oxidoreductase activity of Treponema denticola ATCC 35405 grown in an aerobic and anaerobic gaseous environment.

The cells of a human oral spirochete, Treponema denticola ATCC 35405, and of seven clinical isolates of this organism obtained from the subgingival dental plaque of periodontitis patients were studied for their ability to grow in an aerobic and an anaerobic environment, and for their profile of peptidohydrolase and oxidoreductase enzymes. The growth yield of aerobically grown cultures was either comparable to or higher than that of anaerobically grown ones regardless of whether prereduced broth, freshly prepared broth or oxidized broth was used. However, elimination of certain supplements from the growth media resulted in poor growth regardless of the nature of the gaseous environment. The microscopic morphology and motility of the cells were not affected by differences in the gaseous atmosphere. Quantitative studies on several peptidohydrolase activities suggest that anaerobically grown cells displayed higher specific activity especially toward N alpha-L-prolyl-2-naphthylamine, indicating that increased synthesis of proline iminopeptidase enzymes (or enzyme) of the cells was associated with anaerobic growth conditions. The formation of enzymes hydrolysing N alpha-benzoyl-DL-arginyl-2-naphthylamine (and the corresponding p-nitroaniline) was not affected to the same extent. Growth experiments suggest that T. denticola ATCC 35405 is a facultatively anaerobic spirochete instead of an obligate anaerobe as reported in previous literature. The quantitative enzyme studies suggest that the gaseous growth atmosphere of the cells can exert a selective effect on the activity levels of certain peptidolytic enzymes of this organism. Such effects were not observed when the whole cells were studied by means of qualitative or semi-quantitative enzyme tests. The activities of catalase, peroxidase and superoxide dismutase of the cells were low and variable. Because of this, it was not possible to relate these oxidoreductase activities to the composition of the gaseous atmosphere.

Aerobiosis↗
PubMed1993

Periodontal disease in an Amish population.

Epidemiological studies of periodontal disease have attempted to focus on defined groups in which the variables thought to be responsible for disease could be controlled or more easily identified. This study documents periodontal disease parameters in a unique population of Amish farmers. A total of 371 Amish were contacted and 282 were examined in their homes giving a participation rate of 76%. Ages ranged from 18 to 79 years. Overall means for periodontal conditions were 1.54 mm for attachment loss, 2.63 mm for pocket depth, 0.17 for calculus, 0.63 for plaque and 0.61 for gingivitis. One dental examiner conducted all examinations. Prevalence of periodontal disease tended to be higher among males and increased with age. The majority of Amish examined had little evidence of destructive periodontal disease; about 3.4% of teeth examined had attachment loss of 6 mm or more. These findings indicate a modest level of periodontal disease among the Amish. It is of interest that this population does not generally seek routine dental care. Preliminary analyses of health behavior data collected indicate a lack of regular oral hygiene practices. It appears that the Amish may have protective factors which affect their level of disease.

Adolescent↗
PubMed1992

Purification and substrate specificity of an endopeptidase from the human oral spirochete Treponema denticola ATCC 35405, active on furylacryloyl-Leu-Gly-Pro-Ala and bradykinin.

An endopeptidase was purified to homogeneity from the cell extracts of Treponema denticola ATCC 35405 (a human oral spirochete) by a procedure that comprised dialysis, anion exchange fast protein liquid chromatography (FPLC), hydroxylapatite FPLC, immobilized metal affinity FPLC, FPLC chromatofocusing, and two consecutive gel permeation FPLC steps. The enzyme is a 62-kDa protein with an isoelectric point of 6.5-7.0. Experiments with enzyme inhibitors suggest that this enzyme is a metallopeptidase and that its activity is not dependent on sulfhydryl or serine residues. The enzyme is active on furylacryloyl-Leu-Gly-Pro-Ala (FALGPA; pH optimum near 6.25), bradykinin (Bk), and several Bk-related peptides. In FALGPA, the cleavage site is the Leu-Gly bond. An imino acid is absolutely necessary in position P'2. The shortest hydrolyzed peptide was FALGPA, the hydrolysis of which is strongly and competitively inhibited by Bk (Ki = 5.0 microM). The pyrophosphate ion and phosphoramidon also inhibited the hydrolysis of FALGPA. The enzyme does not hydrolyze all typical synthetic collagenase substrates, Azocoll, Azocasein, or Type I and Type IV collagens, or any other proteins tested. In Bk-related peptides, the hydrolyzed bond was Phe5-Ser6. Since a Bk antagonist and a Bk-potentiating pentapeptide also were good substrates, it is possible that the enzyme hydrolyzes Bks and related peptides only because of the coincidental, specific amino acid sequence of those substrates. A proposal is made that since a substantial portion of the amino acid sequence of FALGPA is present in collagen (and additionally acknowledging that the furylacryloyl residue structurally resembles that of proline), the natural substrates of this enzyme may be small, soluble collagen fragments produced by other enzymes from periodontal connective tissue, and that such peptides are important for the nutrition and pathogenicity of T. denticola.

Acrylates↗
PubMed1992

A new experimental model: the vascular pedicle cutaneous flap over the dorsal aspect (flank and hip) of the rat.

Cutaneous vascular anatomy of the flank and the hip was studied in the rat. Investigation was done by anatomical dissection, ink injection to the axial artery and flap harvesting in living rats. Anatomical dissection and India ink injection revealed that the rat's flank and hip skin derives its blood supply from the iliac branch of the iliolumbar artery, which originates from the lateral aspect of the abdominal aorta. The vascular territory of the iliac branch of the iliolumbar artery was defined as follows: the medial border--along the midline of the back from the 12th rib to the proximal part of the tail; the lateral border-anterior axillary line corresponding with the length of the medial border; the cephalic border--a line joining the medial and lateral border at the level of the 12th rib; and the caudal border--the posterior lateral line of the hip. On the basis of the vascular territory demarcated by India ink injection, bilateral vascular pedicle island cutaneous flaps were harvested in living rats. Results showed total survival of all flaps. This flap is easily made, and it could be used as a reliable model for flap research.

Animals↗
PubMed1992

Cutaneous vascular anatomy of the thoracic region of the dorsum and its role in flap design in the rat.

The cutaneous vascular anatomy of the proximal one-half of the dorsum (the thoracic region) and its role in flap design was studied in the rat. The investigation included anatomical dissection, ink injection into the axial artery, and flap harvesting in live animals. Anatomical dissection and india ink injection of the thoracic region revealed that the skin derives its principal blood supply from the lateral thoracic artery. The cutaneous vascular territory of the lateral thoracic artery was defined as follows: the medial border, along the midline of the back from the level of the inferior angle of the scapula to the lower border of the last rib; the lateral border, anterior axillary line corresponding with the length of the medial border; the cephalic border, a line joining the medial and lateral border at the level of the inferior angle of the scapula; and the caudal border, a line corresponding to the lower border of the last rib. Bilateral vascular pedicle island cutaneous flaps were harvested in living rats based on the vascular territory demarcated by India ink injection. All flaps survived; hence, this flap is reliable, with consistent vascularity, and is easy to harvest, and therefore, can be used as a vascular pedicle experimental model to study flap hemodynamics.

Animals↗
PubMed1992

Effect of slow-release chlorhexidine mouthguards on the levels of selected salivary bacteria.

This study evaluated the effect of an alternate delivery system for chlorhexidine on salivary levels of mutans streptococci (MS) and other selected oral bacteria. On the basis of salivary MS levels > or = 10(4) CFU/ml, 22 subjects were enrolled. All caries lesions were restored prior to treatment. Two pretreatment paraffin-stimulated saliva samples were obtained for culturing at least 1 week apart. Complete-arch vacuum-adapted mouthguards were individually fabricated and coated internally with a 3% w/v chlorhexidine varnish. Mouthguards were worn for an average of 7 h/night for 7 nights. Saliva samples were obtained immediately after treatment and 1 and 3 months later. There was no significant change in levels of any of the monitored bacteria between the two pretreatment samples. A significant and specific reduction in salivary MS levels was observed in the three after-treatment samples as compared with baseline values (p < 0.001, p < 0.001, p < 0.05, respectively). The levels of Actinomyces viscosus were also measured, and there was a significant reduction immediately after treatment (p < 0.05), a return to baseline values at 1 month, and a significant increase above baseline values at 3 months, (p < 0.001). There was no significant change in saliva volume, in total numbers of facultatively anaerobic bacteria, or in levels of lactobacilli or Streptococcus sanguis. This treatment system is capable of significant and specific suppression of MS levels for up to 3 months without retreatment.

Actinomyces viscosus↗
PubMed1992

Clinical and microbiologic comparisons of two dental implant systems.

Clinical soft tissue examination and microbiologic findings were compared for two dental implant systems. Of 20 edentulous patients, ten had been reconstructed with a transosteal implant of gold alloy, TMI-system (Bosker), of and ten with endosseous implants of titanium (Brånemark-system). Clinical parameters evaluated included plaque, gingivitis, sulcus depth and bleeding on probing. Plaque samples from 14 patients were cultured for selected periodontal pathogens. Although some differences in soft tissue clinical behavior were identified, the incidence and prevalence of selected periodontal pathogens appeared to be similar.

Actinomyces viscosus↗
PubMed1991

Experimental study on the influence of tension, immobilisation and denervation on muscle transplantation.

To observe the effects of tension and immobilisation on denervated muscle, rats' denervated soleus muscles were transplanted orthotopically at different tensions: high, neutral, moderate and low tension with immobilisation. Results were evaluated by measuring muscle mass, twitch and tetanic tension, and histologically by HE staining. The results showed better preservation of muscle weight in the high tension group. Atrophy and loss of function were rapid during the first 4 weeks and were greatest in the low tension group. Rate of atrophy was slowed and relatively stabilised at the eighth postoperative week. We conclude that increased tension with immobilisation produced slower initial atrophy and loss of function in denervated muscle flaps. Although slower, the atrophy continued during the prolonged immobilisation and there was no significant difference compared with neutral tension at a later period. Moreover, immobilisation produced atrophy and affected function regardless of the amount of tension. Increased tension decelerates and decreased tension accelerates denervation atrophy of muscle. Thus denervation, immobilisation and reduced tension are all detrimental in muscle transplantation.

Animals↗
PubMed1991

Modeling bacterial damage to pulpal cells in vitro.

There is increasing evidence that access to patent dentinal tubules by bacteria and their products rather than trauma from restorative materials is responsible for subsequent pulpitides. The purpose of this study was to compare the relative cytotoxicity of centrifugal fractions of two bacteria, Fusobacterium nucleatum and Treponema denticola, on L929 cells in monolayer cultures and in the "in vitro pulp chamber." Neutrophilic chemotaxis assays and Limmulus assays were performed to verify biological activity of the various fractions of these bacteria. It was found that T. denticola inhibits new protein synthesis in cultured cells to a much greater extent than F. nucleatum, but that only F. nucleatum fractions are chemoattractive for human neutrophils in the absence of serum. While the chemical nature and molecular weights of the "toxic" materials were not determined, it appeared that eukaryotic protein synthesis inhibition caused by the T. denticola pellet fraction in the in vitro pulp chamber was at least 1000 times less than that caused by the same concentrations in monolayer cultures.

Cells, Cultured↗
PubMed1990

Unilateral VATER association.

We describe a case of unilateral "VATER association." In addition to the VATER manifestations, the patient had hemihypoplasia, unilateral congenital paralysis of a leg, and delayed ossification of the femoral head and carpal bones. All of the manifestations involved the left side of the body. The only drug exposure identified was a Chinese herbal medicine taken by the mother during early pregnancy.

Abnormalities, Multiple↗
PubMed1989

Humoral immune response to selected subgingival plaque microorganisms in insulin-dependent diabetic children.

Juvenile diabetics have been shown to have an increased susceptibility to gingivitis and periodontitis following puberty. However, little data are available on changes in the microbial flora that occur at the onset of puberty. This study was performed to determine if antibacterial antibody titers to selected periodontal disease-associated microorganisms might be helpful in revealing changes in plaque flora at the onset and conclusion of puberty. Sera was obtained from 35 subjects (ages 7 to 18 years) selected from a population of insulin-dependent diabetics. The subjects were given a thorough medical examination which included an assessment of sexual maturation and a dental examination which included the recording of onset and magnitude of bleeding according to the papillary bleeding score. Antibody titers to A. naeslundii (AN), B. intermedius (BI), B. gingivalis (BG), F. nucleatum (FN), A. actinomycetemcomitans (AA), C. ochracea (CO) and T. denticola (TD) were determined using the microELISA. Stratification of antibody titers by age groups (less than or equal to 12 years, 12 to 15 years, greater than 15 years) revealed that titers to AN increased significantly (P less than 0.025, ANOVA) and progressively (P less than 0.05, regression analysis) with increasing age. In contrast, the titers to FN were maximal in the under 12 year group and decreased with age (ANOVA, P less than 0.05; regression analysis, P less than 0.05). There were no significant variations in titers observed for the other microorganisms. Stratification by sexual maturity revealed a similar progressive decrease of the titer to FN (ANOVA, P less than 0.05; regression analysis, P less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Actinomyces↗
PubMed1988

Combined antibiotic (metronidazole) and mechanical treatment effects on the subgingival bacterial flora of sites with recurrent periodontal disease.

5 patients in maintenance, 1-3 years after periodontal therapy who showed sites with reinfected pockets and bleeding despite regular recall visits were selected. Darkfield microscopy from 3 sites in each patient showed an average of 41% spirochetes and 21% motile rods. Probing depths ranged from 7 to 9 mm and loss of clinical attachment from 6 to 13 mm in these sites. The patients were given 3 times 250 mg/day of metronidazole (Flagyl) for 10 days. Darkfield microscopy and microbiological cultures of the subgingival plaque were performed twice prior to the study, at the end of the medication and after 3 weeks, 3 and 6 months. The plaque and gingival indices, probing depth and loss of clinical attachment were recorded. During the medication and at 3 and 6 months, the teeth were scaled and root planed. The samples were obtained with 3 paper points and cultured anaerobically in the glove box on non-selective and selective media and representative bacterial colonies identified by aerobic growth, gram stain and rapid biochemical tests. Presumptive pathogenic micro-organisms including Bacteroides were identified. The % of spirochetes, motile rods and non-motile bacteria were enumerated by darkfield microscopy. The clinical results show that administration of metronidazole and repeated root planing significantly decreased gingival inflammation, probing depth and loss of clinical attachment in reinfected sites. After treatment, these sites harbored significantly less spirochetes and more non-motile bacteria, while motile rods tended to return to baseline levels with time. The combined antibiotic and mechanical therapy resulted in a statistically significant decrease of gram-negative rods, Fusobacteria and Bacteroides gingivalis over 6 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗