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Biomedical subjects

W H Swartz

Publications and source records attributed to W H Swartz.

15 recordsLinked to original sources
PubMed1990

Pulsatile GnRH-stimulated LH release from the human fetal pituitary in vitro: sex-associated differences.

An in-vitro perfusion system was utilized to examine LH release from human fetal (19-24 weeks gestation) anterior pituitaries during repetitive GnRH stimulations. Pituitaries (five male, four female) were dissected into halves, and one hemipituitary of each pair was stimulated with 10-min pulses of 1 nM GnRH administered at 60-min intervals over 24h, whereas the matching hemipituitary received pulses of medium alone. Basal (no GnRH stimulation) LH release from female hemipituitaries was significantly (P less than 0.01) greater than from male hemipituitaries, and the amplitude of LH release associated with GnRH pulses was sixfold greater (P less than 0.001) with female hemipituitaries. Furthermore, the magnitude of LH release associated with individual GnRH pulses was significantly (P less than 0.001) enhanced during the course of female hemipituitary perfusions, but not during perifusion of male hemipituitaries. These studies demonstrate that LH secretion by the female, but not male, mid-gestational human fetal pituitary is increased in response to a physiological pattern and interval of repeated pulsatile GnRH stimulation in vitro.

Female↗
PubMed1988

Pulsatile beta-endorphin release from the human pituitary in vitro.

An in vitro perifusion system was used to characterize spontaneous immunoreactive beta-endorphin (i beta-END) release from 10 human fetal (20-23 weeks gestation) and 2 human adult anterior pituitaries. Spontaneous i beta-END release from fetal anterior pituitaries was pulsatile, with a mean (+/- SE) pulse interval of 9.1 +/- 0.5 minutes, pulse amplitude of 120.8 +/- 46.1 pg with nadir to peak increment of 106.0 +/- 32.9%, and overall release rate of 209.7 +/- 65.0 pg/2 minutes. Blockade of calcium activity with 10 microM verapamil and 4 mM EGTA suppressed the frequency and amplitude of the spontaneous pulsatile i beta-endorphin release (n = 2). Administration of 2 nM human CRF for 20 minutes at the end of 2 perfusions induced 205 and 883% increases of i beta-END release over the preceding basal levels. Administration of 2 nM CRF for 50 minutes at the end of another perifusion led to a greater and prolonged increase (maximum 4620% relative to the immediately preceding basal level) in i beta-END release. Addition of 56 mM KCl during the last 20 minutes of this prolonged CRF stimulation further increased i beta-END release (to 7680% relative to the baseline preceding the CRF stimulation). Each of 4 quarters of adult anterior pituitaries (2 quarters each from 1 male and 1 female) also released i beta-END in a pulsatile fashion, with a pulse interval of 11.8 +/- 2.0 minutes, pulse amplitude of 7.4 +/- 0.8 ng with nadir to peak increment of 51.4 +/- 15.3%, and overall release rate of 21.7 +/- 2.9 ng/2 minutes. These studies demonstrate that i beta-END release from the isolated human anterior pituitary in vitro is characterized by high-frequency pulses, independent of hypothalamic stimulation. This spontaneous calcium-dependent pulsatile i beta-END release apparently reflects the activity of an intrapituitary pulse-generating mechanism.

Adult↗
PubMed1987

Intrinsic pulsatility of ACTH release from the human pituitary in vitro.

An in-vitro perifusion system was used to investigate spontaneous ACTH release from human fetal (21-23 weeks gestation) and adult pituitaries. The pattern of ACTH release from fetal pituitaries (n = 7) exhibited a remarkable pulsatile character with a mean (+/- SEM) pulse interval of 11.3 +/- 0.8 min. The mean pulse amplitude was 49.7 +/- 6.3 pg, with a nadir to peak increment of 90.7 +/- 10.4%. The mean ACTH release rate was 87.2 +/- 13.3 pg/2 min. Addition of the calcium chelator EGTA (4 nM) to the perifusion medium induced a significant (P less than 0.01) decrease in both ACTH release rate (from 102.0 +/- 8.5 to 52.0 +/- 9.9 pg/2 min) and ACTH pulse amplitude (from 57.7 +/- 2.8 to 31.3 +/- 4.6 pg) (n = 3). Administration of either 2 nM corticotrophin releasing factor (CRF) or 56 mM KCl induced 10- and 2-fold increases in ACTH secretion, respectively (n = 2). Quarters of adult human pituitaries (n = 6) also secreted ACTH in a pulsatile fashion, with a pulse interval of 14.8 +/- 1.7 min, pulse amplitude of 86.7 +/- 10.0 pg, nadir to peak increment of 84.5 +/- 9.8%, and overall release rate of 167.2 +/- 8.8 pg/2 min. These studies demonstrate that ACTH release from the isolated human pituitary in vitro is characterized by high frequency/low amplitude pulses, independent of hypothalamic stimulation. Accordingly, this spontaneous calcium-dependent pulsatile ACTH release apparently reflects the activity of an intrinsic intrapituitary pulse-generating mechanism.

Adrenocorticotropic Hormone↗
PubMed1987

Intrinsic pulsatility of luteinizing hormone release from the human pituitary in vitro.

An in vitro perifusion system was used to investigate the spontaneous luteinizing hormone (LH) release from 10 human fetal (21-23 weeks of gestation) and 1 adult female pituitaries. The pattern of LH release from fetal pituitaries (n = 6) exhibited a remarkable pulsatile character with a mean (+/- SE) pulse interval of 12.7 +/- 1.7 min. The mean pulse amplitude was 5.2 +/- 0.9 mIU with a nadir to peak increment of 69.5 +/- 6.4%. The mean LH release rate was 12.3 +/- 3.3 mIU/2 min. Blockade of calcium activity with 0.1 mM verapamil and 4 mM EGTA suppressed the frequency (from 1 pulse/12-20 min to 1 pulse/50-100 min) and amplitude (from 5.4-5.7 mIU to 1.4-2.1 mIU) of this spontaneous pulsatile LH release (n = 2). Administration of 8 nM gonadotropin-releasing hormone induced 255 and 954% increases in LH secretion (n = 2). Each quarter of an adult human pituitary also secreted LH in a pulsatile fashion, with a pulse interval of 15.2 +/- 5.6 min, a pulse amplitude of 5.4 +/- 0.6 mIU, a nadir to peak increment of 67.5 +/- 5.2%, and an overall release rate of 14.8 +/- 0.9 mIU/2 min. These studies demonstrate that LH release from the isolated human pituitary in vitro is characterized by high-frequency/low-amplitude pulses, independent of hypothalamic stimulation. Accordingly, this spontaneous calcium-mediated pulsatile LH release apparently reflects the activity of an intrinsic intrapituitary pulse-generating mechanism.

Female↗
PubMed1987

Hydrops due to myocarditis in a fetus.

At 18 weeks of gestation a fetus was studied sonographically because of advanced maternal age and found to have hydrops of unknown etiology with ascites, pleural, and pericardial effusions. An abortion was performed and in the fetal/placental material myocarditis and thyroiditis were documented. Maternal antibodies to Coxsackie virus B5 showed a onefold rise. Tentatively, the hydrops is assigned to Coxsackie virus myocarditis, a lesion not previously identified in fetuses.

Adult↗
PubMed1986

Human fetal hypothalamic GnRH neurosecretion: dopaminergic regulation in vitro.

An in-vitro perifusion system was used to investigate GnRH release from fetal (21-23 weeks gestation) human hypothalami in response to dopamine (DA) and the DA receptor antagonist haloperidol. Administration of 1 mumol/l DA during five perifusions in which 1 mumol/l haloperidol was added to the medium failed to alter basal GnRH release. In contrast DA evoked a rapid and sustained 95.8 +/- 20.3% increase (P less than 0.01) in GnRH release during five matching perifusions with medium containing the alpha-adrenergic antagonist phentolamine. While exposure to 0.01 mumol/l DA failed to alter basal GnRH release during three perifusions, 0.1 mumol/l DA elicited a 145.7 +/- 65.2% increase (P less than 0.05) in GnRH release in three matching perifusions, indicating a dose-dependent effect. These studies demonstrate that DA can stimulate in-vitro release of GnRH from the mid-gestation fetal human hypothalamus by a DA receptor mediated mechanism.

Dopamine↗
PubMed1979

Prophylaxis of minor febrile and major infectious morbidity following hysterectomy.

A retrospective analysis was conducted of 668 consecutive cases using T-tube suction drainage and/or prophylactic antibiotics as infection prophylaxis for hysterectomy. The data are analyzed for the incidence of minor febrile morbidity (temperature greater than 100.4 for 2 days) and for major infection (hospital stay more than 14 days, reoperation or readmission for the management of pelvic abscess or pelvic thrombophlebitis). The study also compares a minor febrile and major infection group with a noninfected group by measuring parameters of patient discomfort, medical staff effort, and financial costs. It is concluded that 1) minor febrile morbidity frequently follows abdominal (20--30%) and vaginal (30--50%) hysterectomy; 2) minor febrile morbidity has temporary but significant consequences in the form of increased patient discomfort, medical staff effort, and financial costs; 3) major infections are rare following abdominal hysterectomy (less than 0.5%) and uncommon following vaginal hysterectomy (1--4%); 4) suction drainage used alone, prophylactic antibiotics used alone, or a combination of suction drainage and antibiotic prophylaxis is each associated with a statistically significant reduction in the incidence of minor febrile morbidity following both abdominal and vaginal hysterectomy (P = less than 0.01); and 5) such infection prophylaxis may also reduce the incidence of major infection following vaginal hysterectomy.

Abscess↗
PubMed1976

Amniotic fluid embolism with survival.

Well-documented amniotic fluid embolism with survival is an uncommon occurrence. A case is reported with characteristic clinical findings in addition to electrocardiographic evidence of acute right heart strain, disseminated intravascular coagulation, and amniotic fluid debris in central venous blood. The impact of this complication on maternal mortality is emphasized. Aggressive therapy with attention to the basic principles of supportive care offers the best chance of survival.

Adult↗
PubMed1976

T-tube suction drainage and/or prophylactic antibiotics. A randomized study of 451 hysterectomies.

The technics of T-tube suction drainage of the retroperitoneal space and of prophylactic antibiotics were evaluated each alone and then in combination in a randomized study of 451 private patients undergoing abdominal or vaginal hysterectomy. As compared with results in a control group, suction drainage alone and prophylactic antibiotics alone were equally effective in reducing the incidence of postoperative pelvic infection and febrile morbidity. When the two technics were used in combination, there was further reduction in the incidence of pelvic infection and febrile morbidity. However, these results were not statistically different from those of either technic alone. Date are presented to indicate that hysterectomy is performed in a bacteriologically contaminated operative field and that a contaminated fluid collection routinely accumulates in the retroperitoneal space. It is therefore suggested that hysterectomy be managed as a potentially infected surgical wound.

Adult↗
PubMed1976

Family centered maternity care: its relationship to perinatal regionalization and neonatal intensive care.

For several months prior to birth a major portion of a family's attention, conversation, thought, and often worry, is directed toward the idea of a new child. This prolonged attention and anticipation contribute to making childbirth an emotionally charged experience. In psychological terms, it is therefore a critical period of peak motivation for learning, and a time to peak susceptibility to reinforcement. Theory, reason, and scientific evidence indicate thng with childbirth and early postpartum experiences, can significantly affect subsequent parental behaviors, the child's central environment influence. Evidence strongly suggests that these parental attitudes and behaviors so crucial to the child's ultimate well-being are learned rather than derived instinctually, and therefore they are malleable and can be taught, directed, and corrected. Through education and reinforcement it is possible to encourage parental behaviors and child interactions which are products of feelings of control, competence, accomplishment, understanding, and caring. Similarly we can recognize and work toward replacing attitudes, feelings, and behaviors that express fear, worry, and insecurity about the child. Over the past 50 years major changes have occurred in the practice of obstetrics and newborn pediatrics. Other major changes will necessarily occur as we move toward perinatal regionalization. Changes instigated solely on physiologic data can have unrecognized collateral effects on the psychological component of the childbirth experience. All concerned health care personnel, especially obstetricians and pediatricians, can insist that the importance of desirable mother-father-child interactions be recognized and that practices fostering them be afforded a high priority. I would like to endorse a comment from a recent article by Richmond concerning the advent of behavioral pediatrics by adding that behavioral obstetrics is also "an idea whose time has arrived".

Delivery, Obstetric↗
PubMed1975

Suction drainage as an alternative to prophylactic antibiotics for hysterectomy.

A technic is described for suction drainage of the retroperitoneal space. Its use is evaluated in 150 private patients undergoing vaginal or abdominal hysterectomy and compared with 150 private control patients. This technic resulted in an average of 40 cc of fluid (range, 10-200 cc) being suctioned from the retroperitoneal space. With this technic febrile morbidity decreased from 26 to 11% for abdominal hysterectomies and from 32 to 8% for vaginal hysterectomies. Information is offered to explain the physiology of posthysterectomy infections, the effectiveness of prophylactic antibiotics, and the paradox of a febrile morbidity higher for vaginal than for abdominal hysterectomies. The risks in using prophylactic antibiotics routinely are stated, and suction drainage is suggested as a preferable alternative.

Adult↗
PubMedDate not supplied

Making the alternative the mainstream. Maintaining a family-centered focus in a large freestanding birth center for low-income women.

The BirthPlace program in San Diego, California, is an example of a successfully "mainstreamed" alternative maternity care program. It was developed to address an access to prenatal care problem in the county, and it has successfully integrated four systems of care: 1) a private practice of nurse-midwives and obstetricians, 2) the public community clinic system, 3) the tertiary university hospital, and 4) a freestanding birth center. It provides a model of care that, if replicated, could be an answer for ensuring universal access to maternity care in the United States. The BirthPlace program primarily serves a public-funded, Hispanic population, with certified nurse-midwives as the primary providers. The program's greatest challenge has been to maintain a personalized, family-centered focus, which has been the hallmark of freestanding birth centers to date, in the face of large numbers of clients and low reimbursement for care. The program has addressed the challenge of increasing access and cost-effectiveness while ensuring family-centered care through decentralized clinic management, informed consent, culturally sensitive care, and appropriate use of technology. However, in the face of an ever-changing health care system, balancing these issues will remain a constant challenge as we reshape our maternity care services.

Birthing Centers↗