Search PubMed⌕ Search

Biomedical subjects

M H Henry

Publications and source records attributed to M H Henry.

13 recordsLinked to original sources
PubMed1998

Sexual dimorphism in broiler chick embryos and embryonic muscle development in late incubation.

Studies were conducted to compare the weights and the characteristics of the Pectoralis superficialis, Semimembranosus, and Gastrocnemius of male and female chicken embryos at 16 and 20 d of incubation. Male embryos were significantly heavier than females at 16 d of incubation, but not at 20 d. The cross-sectional area of myofibers in the P. superficialis of 20-d-old female embryos was greater than that of males and the area of Semimembranosus myofibers was greater at 16 and 20 d. The Semimembranosus apparent myofiber number of 16-d-old male embryos was greater than of females (P = 0.002). There was a significant increase in apparent myofiber number in this muscle between 16 and 20 d of incubation but there was no sex difference at 20 d. The number of Type I myofibers per 30,000 microm2 area of the Gastrocnemius of 20-d-old male embryos was greater than that in females (P = 0.06). There were no significant sex differences in the protein concentration, DNA concentration, or protein:DNA ratio in the muscles at either age when data were pooled across the whole population. There were significant differences in these characteristics between sire families and in some sire families significant sex differences were noted. The protein:DNA ratio of the muscles increased between 16 and 20 d of incubation and the mitotic index decreased. These data suggest that the muscles of male embryos have more but smaller, myofibers than females, which may be responsible for the sex difference in embryo weight and provide the framework for the greater posthatching muscle growth.

Animals↗
PubMed1997

Characteristics of the pectoralis superficialis and semimembranosus of broiler strain chickens, bantam chickens, and the reciprocal crosses.

At hatch, chicks from bantam sire x broiler dam (BaBr) matings were as heavy as those from broiler sire x broiler dam (BrBr) matings. Both were heavier than pure bantam chicks (BaBa) or chicks from broiler strain sires and bantam dams (BrBa), but weights of the latter two genotypes were identical. The Pectoralis superficialis and Semimembranosus of pure bantam chicks weighed less than those of pure broiler chicks throughout the studies. Muscle weights in the BaBr chicks were markedly heavier than those of genetically similar BrBa chicks at hatch. Genetic influences were quickly expressed and weights of muscles in these two groups had converged by 14 d of age. Myofiber cross-sectional areas at 1 d of age were not clearly associated with genotype or maternal environment, but clear patterns had begun to develop by 4 d of age. Myofiber area of both muscles was greater in BrBr than BaBa chicks by this age and after. Myofiber areas in the reciprocal crosses converged toward each other and away from the pure line chicks. By 11 d, the area of Pectoralis myofibers of BrBr chicks was greatest, those of the reciprocal crosses was intermediate and equal to each other, and that of BaBa chicks was least. A similar trend was apparent in Semimembranosus fibers by 11 d but the differences did not become significant until 21 d of age. Significant differences in myofiber number of the Semimembranosus were present (BrBr > BaBr > BrBa > BaBa). Thus, differences in muscle mass were the result of differences in both fiber number and fiber size.

Analysis of Variance↗
PubMed1997

Comparison of embryos and chicks that developed as single individuals in double yolk eggs with those that developed in single yolk eggs.

Body weight and muscle characteristics of 18- to 20-d-old broiler strain embryos developing in double yolk eggs (DY) that contained one embryo and one infertile ovum were compared with embryos in single yolk eggs (SY). Similar comparisons were made in the posthatching period. In some DY eggs, the embryos were bathed in a watery yolk-like fluid with no distinct second yolk present (Type 1 embryo). In others, the second yolk was contained within the vitelline membrane and surrounded by a vascularized membrane (Type 2). These embryos were heavier than Type 1 or embryos in SY eggs by 20 d of incubation. Their Pectoralis superficialis were heavier and had significantly more protein and DNA. Chicks that hatched from the DY eggs were heavier than those that hatched from SY eggs and they had heavier P. superficialis through at least 14 d of age. Pectoralis superficialis myofibers of chicks from DY eggs had greater cross-sectional area than those from SY eggs. Myofibers in the Semimembranosus of 7- and 14 d-old chicks from DY eggs tended to be larger than those from SY eggs, but the differences were not significant. There was no difference in apparent myofiber number in the Semimembranosus of the two types of chicks. The difference in BW between the two types of chicks diminished over time, so that by 42 d of age they were virtually identical. In summary, a nutritionally enriched in ovo environment resulted in embryos and chicks with enhanced growth and muscle mass, but the effects of enrichment diminished during posthatching life and eventually disappeared.

Animals↗
PubMed1996

Anterior shoulder instability. Current review.

During the past several decades, the treatment of anterior shoulder instability has evolved substantially. Treatment initially was based on conservative management with rehabilitation protocols for shoulder girdle strengthening. Functionally disabling instability and recurrent dislocation precluded the acceptance of conservative management as the definitive treatment for all patients. Attention then was turned to open repair strategies. Despite generally positive results, a significant number of complications became evident. With time, however, techniques improved and surgical complications were lessened. As shoulder arthroscopy was more widely practiced, the surgical reconstruction of instability became significantly less invasive. A high learning curve has been associated with the new arthroscopic techniques, and higher redislocation rates than those of open procedures have limited their acceptance by many orthopaedic surgeons. This review article examines the anatomy and pathology of anterior shoulder dislocations, and critically reviews the actual laboratory and clinical data supporting use of these various treatment options. Only through careful examination of well-controlled scientific studies can clinicians devise their own treatment protocol for symptomatic anterior instability of the shoulder.

Arthroscopy↗
PubMed1995

Arthroscopic management of the acromioclavicular joint disorder. A review.

Acromioclavicular joint symptoms may originate from either osteolysis or osteoarthritis. Initial treatment consists of 6 to 12 months of physical therapy, nonsteroidal antiinflammatory drugs, avoidance of exacerbating activities, and other conservative modalities. The majority of patients respond well, but a few remain unable to return to their previous or desired activity levels. Previously this group of patients underwent open resection of the distal clavicle. [The approach violates the deltotrapezial fascia, weakening the surgically treated extremity, which has caused controversy in the literature.] Even without complications, the recovery and time away from work is prolonged. With advances in arthroscopic techniques, resection of the distal clavicle and medial aspect of the acromion has become possible with minimal invasiveness. The arthroscopic technique offers the advantages of rapid rehabilitation with excellent functional results. Several different modifications of 2 basic approaches, the bursal and direct superior, have been described by various authors. The authors sought to examine critically and review the data supporting the choice of arthroscopic surgery rather than an open technique, as well as the advantages of 1 arthroscopic approach over the other.

Acromioclavicular Joint↗
PubMed1978

Skin polyamine levels in psoriasis: the effect of dithranol therapy.

Concentrations of putrescine, spermidine and spermine were determined in biopsies of skin of eight control subjects and of uninvolved skin and skin lesions of eight psoriatic patients before and after topical therapy with dithranol. Mean spermidine and spermine concentrations in uninvolved skin of psoriatic patients were normal, but putrescine concentration was elevated. In psoriatic skin lesions all three amines were significantly elevated. Chemotherapy effectively reduced polyamine concentrations in involved skin touards normal. This decrease in polyamine levels correlated with reduction of the proliferative activity of the epidermis and with clinical improvement of the patients.

Adolescent↗
PubMedDate not supplied

Diagnosis of glenoid labral tears. A comparison between magnetic resonance imaging and clinical examinations.

We studied 54 patients with shoulder pain secondary to anterior instability or glenoid labral tears refractory to 6 months of conservative management with no evidence of rotator cuff lesions. All patients had sufficient preoperative clinical data, magnetic resonance imaging, and shoulder arthroscopy results for analysis. The ability to predict the presence of a glenoid labral tear by physical examination was compared with that of magnetic resonance imaging (conventional and arthrogram) and confirmed with arthroscopy. There were 37 men and 17 women (average age, 34 years) in the study group. Of this group, 64% were throwing athletes and 61% recalled specific traumatic events. Clinical assessment included history with specific attention to pain with overhead activities, clicking, and instances of shoulder instability. Physical examination included the apprehension, relocation, load and shift, inferior sulcus sign, and crank tests. Shoulder arthroscopy confirmed labral tears in 41 patients (76%). Magnetic resonance imaging produced a sensitivity of 59% and a specificity of 85%. Physical examination yielded a sensitivity of 90% and a specificity of 85%. Physical examination is more accurate in predicting glenoid labral tears than magnetic resonance imaging. In this era of cost containment, completing the diagnostic workup in the clinic without expensive ancillary studies allows the patient's care to proceed in the most timely and economic fashion. Glenoid labral tears have been associated with overhead throwing activities, trauma, and shoulder instability. Assessment of an athlete with shoulder pain should take into account a careful history of clicking sounds or catching, symptoms with overhead activities, reports of instability, or previous trauma. On physical examination, patients with labral tears often demonstrate objective instability with or without clicking or catching during glenohumeral rotation. Plain radiographs have not been helpful, and radiologists have relied on techniques from arthrogram to arthrotomogram, CT arthrogram, magnetic resonance imaging (MRI), and MR arthrogram to assist in the diagnosis. Various sensitivities and specificities have been reported for these tests. However, a large degree of intra- and interobserver variability has been demonstrated, and the degree to which these studies are helpful in preoperative planning has been questioned. No previous study to our knowledge has involved MRI in a direct comparison of other diagnostic modalities. Therefore, the purpose of this study is to investigate the accuracy of MRI and physical examination in the diagnosis of glenoid labral tears.

Adolescent↗
PubMedDate not supplied

A prospective evaluation of a new physical examination in predicting glenoid labral tears.

We studied 62 patients (40 men and 22 women) with an average age of 28 years over a 28-month period who presented with shoulder pain that was refractory to 3 months of conservative management. Patients with a prior glenohumeral dislocation or a rotator cuff tear were excluded. The "crank" test was performed with the arm elevated to 160 degrees in the scapular plane of the body, loaded axially along the humerus, and with maximal internal and external rotation. Although similar tests have been described, the crank test is a new examination previously unreported. Half of the patients (31) had a positive crank test. Arthroscopy performed on all 62 patients revealed glenoid labral tears in 32 patients. Two patients who had positive crank tests did not have labral tears but had partial-thickness, articular-side rotator cuff tears. The sensitivity of the crank test was 91%, the specificity was 93%, the positive predictive value was 94%, and the negative predictive value was 90%. With these data, the crank test fulfills the criteria as a single physical examination test that is highly accurate for the preoperative diagnosis of glenoid labral tears. Accordingly, expensive imaging modalities currently used in this patient population may be employed less in the future.

Adolescent↗